draft for managing follow requests

- the application actor is managed manually by default
- no admin-options are included yet
- the old new follower table only is used hardcoded by the application actor
- no admin notifications are send yet
- todo: a lot more

FEDERATION.md

@@ -14,6 +14,7 @@ The WordPress plugin largely follows ActivityPub's server-to-server specificatio
 - [FEP-f1d5: NodeInfo in Fediverse Software](https://codeberg.org/fediverse/fep/src/branch/main/fep/f1d5/fep-f1d5.md)
 - [FEP-67ff: FEDERATION.md](https://codeberg.org/fediverse/fep/src/branch/main/fep/67ff/fep-67ff.md)
 - [FEP-5feb: Search indexing consent for actors](https://codeberg.org/fediverse/fep/src/branch/main/fep/5feb/fep-5feb.md)
+- [FEP-2677: Identifying the Application Actor](https://codeberg.org/fediverse/fep/src/branch/main/fep/2677/fep-2677.md)
 
 Partially supported FEPs
 

README.md

@@ -1,9 +1,9 @@
 # ActivityPub #
 **Contributors:** [automattic](https://profiles.wordpress.org/automattic/), [pfefferle](https://profiles.wordpress.org/pfefferle/), [mediaformat](https://profiles.wordpress.org/mediaformat/), [mattwiebe](https://profiles.wordpress.org/mattwiebe/), [akirk](https://profiles.wordpress.org/akirk/), [jeherve](https://profiles.wordpress.org/jeherve/), [nuriapena](https://profiles.wordpress.org/nuriapena/), [cavalierlife](https://profiles.wordpress.org/cavalierlife/)  
 **Tags:** OStatus, fediverse, activitypub, activitystream  
-**Requires at least:** 4.7  
+**Requires at least:** 5.5  
 **Tested up to:** 6.4  
-**Stable tag:** 1.2.0  
+**Stable tag:** 1.3.0  
 **Requires PHP:** 5.6  
 **License:** MIT  
 **License URI:** http://opensource.org/licenses/MIT  
@@ -68,10 +68,10 @@ Implemented:
 * share posts
 * receive comments/reactions
 * signature verification
+* threaded comments support
 
 To implement:
 
-* threaded comments support
 * replace shortcodes with blocks for layout
 
 ### What is "ActivityPub for WordPress" ###
@@ -105,6 +105,27 @@ Where 'blog' is the path to the subdirectory at which your blog resides.
 
 Project maintained on GitHub at [automattic/wordpress-activitypub](https://github.com/automattic/wordpress-activitypub).
 
+### 2.0.0 ###
+
+* Removed: Deprecated Classes
+* Fixed: Normalize attributes that can have mixed value types
+* Added: URL support for WebFinger
+* Added: Make Post-Template filterable
+* Added: CSS class for ActivityPub comments to allow custom designs
+* Added: FEP-2677: Identifying the Application Actor
+* Added: Basic Comment Federation
+* Added: Profile Update Activities
+* Improved: WebFinger endpoints
+
+### 1.3.0 ###
+
+* Added: Threaded-Comments support
+* Improved: alt text for avatars in Follow Me/Followers blocks
+* Improved: `Delete`, `Update` and `Follow` Activities
+* Improved: better/more effective handling of `Delete` Activities
+* Improved: allow `<p />` and `<br />` for Comments
+* Fixed: removed default limit of WP_Query to send updates to all Inboxes and not only to the first 10
+
 ### 1.2.0 ###
 
 * Add: Search and order followerer lists

activitypub.php

@@ -3,7 +3,7 @@
  * Plugin Name: ActivityPub
  * Plugin URI: https://github.com/pfefferle/wordpress-activitypub/
  * Description: The ActivityPub protocol is a decentralized social networking protocol based upon the ActivityStreams 2.0 data format.
- * Version: 1.2.0
+ * Version: 1.3.0
  * Author: Matthias Pfefferle & Automattic
  * Author URI: https://automattic.com/
  * License: MIT
@@ -33,15 +33,13 @@ require_once __DIR__ . '/includes/functions.php';
 \defined( 'ACTIVITYPUB_CUSTOM_POST_CONTENT' ) || \define( 'ACTIVITYPUB_CUSTOM_POST_CONTENT', "<strong>[ap_title]</strong>\n\n[ap_content]\n\n[ap_hashtags]\n\n[ap_shortlink]" );
 \defined( 'ACTIVITYPUB_AUTHORIZED_FETCH' ) || \define( 'ACTIVITYPUB_AUTHORIZED_FETCH', false );
 \defined( 'ACTIVITYPUB_DISABLE_REWRITES' ) || \define( 'ACTIVITYPUB_DISABLE_REWRITES', false );
-\defined( 'ACTIVITYPUB_DEFAULT_TRANSFORMER' ) || \define( 'ACTIVITYPUB_DEFAULT_TRANSFORMER', 'activitypub/default' );
+\defined( 'ACTIVITYPUB_SHARED_INBOX_FEATURE' ) || \define( 'ACTIVITYPUB_SHARED_INBOX_FEATURE', false );
-
 
 \define( 'ACTIVITYPUB_PLUGIN_DIR', plugin_dir_path( __FILE__ ) );
 \define( 'ACTIVITYPUB_PLUGIN_BASENAME', plugin_basename( __FILE__ ) );
 \define( 'ACTIVITYPUB_PLUGIN_FILE', plugin_dir_path( __FILE__ ) . '/' . basename( __FILE__ ) );
 \define( 'ACTIVITYPUB_PLUGIN_URL', plugin_dir_url( __FILE__ ) );
 
-
 /**
  * Initialize REST routes.
  */
@@ -69,7 +67,7 @@ function plugin_init() {
 	\add_action( 'init', array( __NAMESPACE__ . '\Migration', 'init' ) );
 	\add_action( 'init', array( __NAMESPACE__ . '\Activitypub', 'init' ) );
 	\add_action( 'init', array( __NAMESPACE__ . '\Activity_Dispatcher', 'init' ) );
-	\add_action( 'init', array( __NAMESPACE__ . '\Collection\Followers', 'init' ) );
+	\add_action( 'init', array( __NAMESPACE__ . '\Handler', 'init' ) );
 	\add_action( 'init', array( __NAMESPACE__ . '\Admin', 'init' ) );
 	\add_action( 'init', array( __NAMESPACE__ . '\Hashtag', 'init' ) );
 	\add_action( 'init', array( __NAMESPACE__ . '\Mention', 'init' ) );
@@ -174,13 +172,21 @@ function plugin_settings_link( $actions ) {
  */
 add_action(
 	'bp_include',
-	function() {
+	function () {
 		require_once __DIR__ . '/integration/class-buddypress.php';
 		Integration\Buddypress::init();
 	},
 	0
 );
 
+add_action(
+	'wp_ajax_activitypub_handle_follow_request',
+	function () {
+		$wp_list_table = new \Activitypub\Table\Follow_Requests();
+		$wp_list_table->ajax_response();
+	}
+);
+
 /**
  * `get_plugin_data` wrapper
  *

assets/css/activitypub-admin.css

@@ -197,3 +197,36 @@ input.blog-user-identifier {
 	border-bottom: none;
 	margin-bottom: 0;
 }
+
+.activitypub-settings-label {
+	display: inline-block;
+	padding: .25em .4em;
+	font-size: 85%;
+	font-weight: 700;
+	line-height: 1.25;
+	text-align: center;
+	white-space: nowrap;
+	vertical-align: baseline;
+	border-radius: .25rem;
+}
+
+.activitypub-settings-label-success {
+	color: #fff;
+ 	background-color: #28a745;
+}
+
+.activitypub-settings-label-warning {
+	color: #212529;
+	background-color: #ffc107;
+}
+
+.activitypub-settings-label-danger {
+	color: #fff;
+	background-color: #dc3545;
+}
+
+.activitypub-settings-action-buttons {
+	display: flex;
+    gap: 5px;
+    flex-wrap: nowrap;
+}

assets/js/activitypub-admin.js

@@ -1,4 +1,5 @@
 jQuery( function( $ ) {
+	const { __ } = wp.i18n;
 	// Accordion handling in various areas.
 	$( '.activitypub-settings-accordion' ).on( 'click', '.activitypub-settings-accordion-trigger', function() {
 		var isExpanded = ( 'true' === $( this ).attr( 'aria-expanded' ) );
@@ -17,4 +18,51 @@ jQuery( function( $ ) {
 			$( '.activate-now' ).removeClass( 'thickbox open-plugin-details-modal' );
 		}, 1200 );
 	} );
+	
+	$( '.activitypub-settings-action-buttons' ).on( 'click', '.button', function() {
+		var button = $ (this );
+		var actionValue = button.data('action');
+		window.console.log( actionValue );
+		$.ajax({
+            type: 'POST',
+            url: actionValue,
+            success: function ( response ) {
+				var statusText = button.closest( 'td' ).siblings( '.column-status' ).children( 'span' ).first();
+				if ( 'deleted' === response ) {
+					button.closest( 'tr' ).remove();
+				}
+				if ( 'approved' === response ) {
+					button.parent().find( '[data-action*="follow_action=reject"] ').attr( 'type', 'button' );
+					button.parent().find( '[data-action*="follow_action=delete"]' ).attr( 'type', 'hidden' );
+					statusText.text( __( 'Approved', 'activitypub' ) );
+					statusText.removeClass( 'activitypub-settings-label-danger' );
+					statusText.removeClass( 'activitypub-settings-label-warning' );
+					statusText.addClass( 'activitypub-settings-label-success' );
+				}
+				if ( 'rejected' === response ) {
+					// TODO: clarify this behavior together with Mobilizon and others.
+					button.closest( 'tr' ).remove();
+					// statusText.text( __( 'Rejected', 'activitypub' ) );
+					// statusText.removeClass( 'activitypub-settings-label-success' );
+					// statusText.removeClass( 'activitypub-settings-label-warning' );
+					// statusText.addClass( 'activitypub-settings-label-danger' );
+					// button.parent().find( '[data-action*="follow_action=approve"]' ).attr( 'type', 'button' );
+					// button.parent().find( '[data-action*="follow_action=delete"]' ).attr( 'type', 'button' );
+				}
+				button.attr( 'type', 'hidden' );
+				// Check if table is completely empty.
+				var tbody = button.closest( 'tbody' );
+				if ( 0 == tbody.find( 'tr' ).length ) {
+					var text = __( 'No items found.', 'core' );
+					var newRow = $('<tr>').append($('<td>', { class: 'colspanchange', colspan: 7, text: text }));
+					tbody.append(newRow);
+					tbody.append("Some appended text.");
+				}
+            },
+            error: function ( error ) {
+                // TODO: Handle the error
+            }
+        });
+	} );
+
 } );

build/follow-me/index.asset.php

@@ -1 +1 @@
-<?php return array('dependencies' => array('wp-api-fetch', 'wp-block-editor', 'wp-blocks', 'wp-components', 'wp-compose', 'wp-data', 'wp-element', 'wp-i18n', 'wp-primitives'), 'version' => '2a185b1c488886051601');
+<?php return array( 'dependencies' => array( 'wp-api-fetch', 'wp-block-editor', 'wp-blocks', 'wp-components', 'wp-compose', 'wp-data', 'wp-element', 'wp-i18n', 'wp-primitives' ), 'version' => '6aeec6336fd28aa836a7' );

build/follow-me/view.asset.php

@@ -1 +1 @@
-<?php return array('dependencies' => array('wp-api-fetch', 'wp-components', 'wp-compose', 'wp-dom-ready', 'wp-element', 'wp-i18n', 'wp-primitives'), 'version' => '17a158ceced1355cc8ea');
+<?php return array( 'dependencies' => array( 'wp-api-fetch', 'wp-components', 'wp-compose', 'wp-dom-ready', 'wp-element', 'wp-i18n', 'wp-primitives' ), 'version' => '5b48281e37700a970a66' );

build/followers/index.asset.php

@@ -1 +1 @@
-<?php return array('dependencies' => array('react', 'wp-api-fetch', 'wp-block-editor', 'wp-blocks', 'wp-components', 'wp-data', 'wp-element', 'wp-i18n', 'wp-primitives', 'wp-url'), 'version' => '1cbd9cbfcbd7fc813429');
+<?php return array( 'dependencies' => array( 'react', 'wp-api-fetch', 'wp-block-editor', 'wp-blocks', 'wp-components', 'wp-data', 'wp-element', 'wp-i18n', 'wp-primitives', 'wp-url' ), 'version' => '59d9702e06860a6d13e4' );

build/followers/index.js

@@ -1,3 +1,3 @@
 (()=>{var e={184:(e,t)=>{var a;!function(){"use strict";var n={}.hasOwnProperty;function l(){for(var e=[],t=0;t<arguments.length;t++){var a=arguments[t];if(a){var r=typeof a;if("string"===r||"number"===r)e.push(a);else if(Array.isArray(a)){if(a.length){var o=l.apply(null,a);o&&e.push(o)}}else if("object"===r){if(a.toString!==Object.prototype.toString&&!a.toString.toString().includes("[native code]")){e.push(a.toString());continue}for(var i in a)n.call(a,i)&&a[i]&&e.push(i)}}}return e.join(" ")}e.exports?(l.default=l,e.exports=l):void 0===(a=function(){return l}.apply(t,[]))||(e.exports=a)}()}},t={};function a(n){var l=t[n];if(void 0!==l)return l.exports;var r=t[n]={exports:{}};return e[n](r,r.exports,a),r.exports}a.n=e=>{var t=e&&e.__esModule?()=>e.default:()=>e;return a.d(t,{a:t}),t},a.d=(e,t)=>{for(var n in t)a.o(t,n)&&!a.o(e,n)&&Object.defineProperty(e,n,{enumerable:!0,get:t[n]})},a.o=(e,t)=>Object.prototype.hasOwnProperty.call(e,t),(()=>{"use strict";const e=window.wp.blocks,t=window.wp.element,n=window.wp.primitives,l=(0,t.createElement)(n.SVG,{xmlns:"http://www.w3.org/2000/svg",viewBox:"0 0 24 24"},(0,t.createElement)(n.Path,{d:"M15.5 9.5a1 1 0 100-2 1 1 0 000 2zm0 1.5a2.5 2.5 0 100-5 2.5 2.5 0 000 5zm-2.25 6v-2a2.75 2.75 0 00-2.75-2.75h-4A2.75 2.75 0 003.75 15v2h1.5v-2c0-.69.56-1.25 1.25-1.25h4c.69 0 1.25.56 1.25 1.25v2h1.5zm7-2v2h-1.5v-2c0-.69-.56-1.25-1.25-1.25H15v-1.5h2.5A2.75 2.75 0 0120.25 15zM9.5 8.5a1 1 0 11-2 0 1 1 0 012 0zm1.5 0a2.5 2.5 0 11-5 0 2.5 2.5 0 015 0z",fillRule:"evenodd"}));function r(){return r=Object.assign?Object.assign.bind():function(e){for(var t=1;t<arguments.length;t++){var a=arguments[t];for(var n in a)Object.prototype.hasOwnProperty.call(a,n)&&(e[n]=a[n])}return e},r.apply(this,arguments)}const o=window.wp.components,i=window.wp.blockEditor,c=window.wp.i18n,s=window.React,p=window.wp.apiFetch;var u=a.n(p);const v=window.wp.url;var m=a(184),b=a.n(m);function w(e){let{active:a,children:n,page:l,pageClick:r,className:o}=e;const i=b()("wp-block activitypub-pager",o,{current:a});return(0,t.createElement)("a",{className:i,onClick:e=>{e.preventDefault(),!a&&r(l)}},n)}const d={outlined:"outlined",minimal:"minimal"};function f(e){let{compact:a,nextLabel:n,page:l,pageClick:r,perPage:o,prevLabel:i,total:c,variant:s=d.outlined}=e;const p=((e,t)=>{let a=[1,e-2,e-1,e,e+1,e+2,t];a.sort(((e,t)=>e-t)),a=a.filter(((e,a,n)=>e>=1&&e<=t&&n.lastIndexOf(e)===a));for(let e=a.length-2;e>=0;e--)a[e]===a[e+1]&&a.splice(e+1,1);return a})(l,Math.ceil(c/o)),u=b()("alignwide wp-block-query-pagination is-content-justification-space-between is-layout-flex wp-block-query-pagination-is-layout-flex",`is-${s}`,{"is-compact":a});return(0,t.createElement)("nav",{className:u},i&&(0,t.createElement)(w,{key:"prev",page:l-1,pageClick:r,active:1===l,"aria-label":i,className:"wp-block-query-pagination-previous block-editor-block-list__block"},i),!a&&(0,t.createElement)("div",{className:"block-editor-block-list__block wp-block wp-block-query-pagination-numbers"},p.map((e=>(0,t.createElement)(w,{key:e,page:e,pageClick:r,active:e===l,className:"page-numbers"},e)))),n&&(0,t.createElement)(w,{key:"next",page:l+1,pageClick:r,active:l===Math.ceil(c/o),"aria-label":n,className:"wp-block-query-pagination-next block-editor-block-list__block"},n))}const{namespace:g}=window._activityPubOptions;function y(e){let{selectedUser:a,per_page:n,order:l,title:o,page:i,setPage:p,className:m="",followLinks:b=!0,followerData:w=!1}=e;const d="site"===a?0:a,[y,k]=(0,s.useState)([]),[E,_]=(0,s.useState)(0),[x,C]=(0,s.useState)(0),[S,O]=function(){const[e,t]=(0,s.useState)(1);return[e,t]}(),N=i||S,P=p||O,L=(0,t.createInterpolateElement)(/* translators: arrow for previous followers link */
 (0,c.__)("<span>←</span> Less","activitypub"),{span:(0,t.createElement)("span",{class:"wp-block-query-pagination-previous-arrow is-arrow-arrow","aria-hidden":"true"})}),j=(0,t.createInterpolateElement)(/* translators: arrow for next followers link */
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+(0,c.__)("More <span>→</span>","activitypub"),{span:(0,t.createElement)("span",{class:"wp-block-query-pagination-next-arrow is-arrow-arrow","aria-hidden":"true"})}),M=(e,t)=>{k(e),C(t),_(Math.ceil(t/n))};return(0,s.useEffect)((()=>{if(w&&1===N)return M(w.followers,w.total);const e=function(e,t,a,n){const l=`/${g}/users/${e}/followers`,r={per_page:t,order:a,page:n,context:"full"};return(0,v.addQueryArgs)(l,r)}(d,n,l,N);u()({path:e}).then((e=>M(e.orderedItems,e.totalItems))).catch((()=>{}))}),[d,n,l,N,w]),(0,t.createElement)("div",{className:"activitypub-follower-block "+m},(0,t.createElement)("h3",null,o),(0,t.createElement)("ul",null,y&&y.map((e=>(0,t.createElement)("li",{key:e.url},(0,t.createElement)(h,r({},e,{followLinks:b})))))),E>1&&(0,t.createElement)(f,{page:N,perPage:n,total:x,pageClick:P,nextLabel:j,prevLabel:L,compact:"is-style-compact"===m}))}function h(e){let{name:a,icon:n,url:l,preferredUsername:i,followLinks:c=!0}=e;const s=`@${i}`,p={};return c||(p.onClick=e=>e.preventDefault()),(0,t.createElement)(o.ExternalLink,r({className:"activitypub-link",href:l,title:s},p),(0,t.createElement)("img",{width:"40",height:"40",src:n.url,class:"avatar activitypub-avatar",alt:a}),(0,t.createElement)("span",{class:"activitypub-actor"},(0,t.createElement)("strong",{className:"activitypub-name"},a),(0,t.createElement)("span",{class:"sep"},"/"),(0,t.createElement)("span",{class:"activitypub-handle"},s)))}const k=window.wp.data,E=window._activityPubOptions?.enabled;(0,e.registerBlockType)("activitypub/followers",{edit:function(e){let{attributes:a,setAttributes:n}=e;const{order:l,per_page:s,selectedUser:p,title:u}=a,v=(0,i.useBlockProps)(),[m,b]=(0,t.useState)(1),w=[{label:(0,c.__)("New to old","activitypub"),value:"desc"},{label:(0,c.__)("Old to new","activitypub"),value:"asc"}],d=function(){const e=E?.users?(0,k.useSelect)((e=>e("core").getUsers({who:"authors"}))):[];return(0,t.useMemo)((()=>{if(!e)return[];const t=E?.site?[{label:(0,c.__)("Whole Site","activitypub"),value:"site"}]:[];return e.reduce(((e,t)=>(e.push({label:t.name,value:`${t.id}`}),e)),t)}),[e])}(),f=e=>t=>{b(1),n({[e]:t})};return(0,t.useEffect)((()=>{d.length&&(d.find((e=>{let{value:t}=e;return t===p}))||n({selectedUser:d[0].value}))}),[p,d]),(0,t.createElement)("div",v,(0,t.createElement)(i.InspectorControls,{key:"setting"},(0,t.createElement)(o.PanelBody,{title:(0,c.__)("Followers Options","activitypub")},(0,t.createElement)(o.TextControl,{label:(0,c.__)("Title","activitypub"),help:(0,c.__)("Title to display above the list of followers. Blank for none.","activitypub"),value:u,onChange:e=>n({title:e})}),d.length>1&&(0,t.createElement)(o.SelectControl,{label:(0,c.__)("Select User","activitypub"),value:p,options:d,onChange:f("selectedUser")}),(0,t.createElement)(o.SelectControl,{label:(0,c.__)("Sort","activitypub"),value:l,options:w,onChange:f("order")}),(0,t.createElement)(o.RangeControl,{label:(0,c.__)("Number of Followers","activitypub"),value:s,onChange:f("per_page"),min:1,max:10}))),(0,t.createElement)(y,r({},a,{page:m,setPage:b,followLinks:!1})))},save:()=>null,icon:l})})()})();

build/followers/view.asset.php

@@ -1 +1 @@
-<?php return array('dependencies' => array('react', 'wp-api-fetch', 'wp-components', 'wp-dom-ready', 'wp-element', 'wp-i18n', 'wp-url'), 'version' => 'f0e21057f7ec615290d6');
+<?php return array( 'dependencies' => array( 'react', 'wp-api-fetch', 'wp-components', 'wp-dom-ready', 'wp-element', 'wp-i18n', 'wp-url' ), 'version' => '04e51e7562fe28b0b2c3' );

build/followers/view.js

@@ -1,3 +1,3 @@
 (()=>{var e,t={189:(e,t,a)=>{"use strict";const r=window.wp.element;function n(){return n=Object.assign?Object.assign.bind():function(e){for(var t=1;t<arguments.length;t++){var a=arguments[t];for(var r in a)Object.prototype.hasOwnProperty.call(a,r)&&(e[r]=a[r])}return e},n.apply(this,arguments)}const l=window.React,o=window.wp.apiFetch;var i=a.n(o);const c=window.wp.url,s=window.wp.i18n;var p=a(184),u=a.n(p);function m(e){let{active:t,children:a,page:n,pageClick:l,className:o}=e;const i=u()("wp-block activitypub-pager",o,{current:t});return(0,r.createElement)("a",{className:i,onClick:e=>{e.preventDefault(),!t&&l(n)}},a)}const v={outlined:"outlined",minimal:"minimal"};function f(e){let{compact:t,nextLabel:a,page:n,pageClick:l,perPage:o,prevLabel:i,total:c,variant:s=v.outlined}=e;const p=((e,t)=>{let a=[1,e-2,e-1,e,e+1,e+2,t];a.sort(((e,t)=>e-t)),a=a.filter(((e,a,r)=>e>=1&&e<=t&&r.lastIndexOf(e)===a));for(let e=a.length-2;e>=0;e--)a[e]===a[e+1]&&a.splice(e+1,1);return a})(n,Math.ceil(c/o)),f=u()("alignwide wp-block-query-pagination is-content-justification-space-between is-layout-flex wp-block-query-pagination-is-layout-flex",`is-${s}`,{"is-compact":t});return(0,r.createElement)("nav",{className:f},i&&(0,r.createElement)(m,{key:"prev",page:n-1,pageClick:l,active:1===n,"aria-label":i,className:"wp-block-query-pagination-previous block-editor-block-list__block"},i),!t&&(0,r.createElement)("div",{className:"block-editor-block-list__block wp-block wp-block-query-pagination-numbers"},p.map((e=>(0,r.createElement)(m,{key:e,page:e,pageClick:l,active:e===n,className:"page-numbers"},e)))),a&&(0,r.createElement)(m,{key:"next",page:n+1,pageClick:l,active:n===Math.ceil(c/o),"aria-label":a,className:"wp-block-query-pagination-next block-editor-block-list__block"},a))}const b=window.wp.components,{namespace:d}=window._activityPubOptions;function w(e){let{selectedUser:t,per_page:a,order:o,title:p,page:u,setPage:m,className:v="",followLinks:b=!0,followerData:w=!1}=e;const y="site"===t?0:t,[k,h]=(0,l.useState)([]),[E,O]=(0,l.useState)(0),[x,_]=(0,l.useState)(0),[N,j]=function(){const[e,t]=(0,l.useState)(1);return[e,t]}(),S=u||N,C=m||j,L=(0,r.createInterpolateElement)(/* translators: arrow for previous followers link */
 (0,s.__)("<span>←</span> Less","activitypub"),{span:(0,r.createElement)("span",{class:"wp-block-query-pagination-previous-arrow is-arrow-arrow","aria-hidden":"true"})}),q=(0,r.createInterpolateElement)(/* translators: arrow for next followers link */
-(0,s.__)("More <span>→</span>","activitypub"),{span:(0,r.createElement)("span",{class:"wp-block-query-pagination-next-arrow is-arrow-arrow","aria-hidden":"true"})}),P=(e,t)=>{h(e),_(t),O(Math.ceil(t/a))};return(0,l.useEffect)((()=>{if(w&&1===S)return P(w.followers,w.total);const e=function(e,t,a,r){const n=`/${d}/users/${e}/followers`,l={per_page:t,order:a,page:r,context:"full"};return(0,c.addQueryArgs)(n,l)}(y,a,o,S);i()({path:e}).then((e=>P(e.orderedItems,e.totalItems))).catch((()=>{}))}),[y,a,o,S,w]),(0,r.createElement)("div",{className:"activitypub-follower-block "+v},(0,r.createElement)("h3",null,p),(0,r.createElement)("ul",null,k&&k.map((e=>(0,r.createElement)("li",{key:e.url},(0,r.createElement)(g,n({},e,{followLinks:b})))))),E>1&&(0,r.createElement)(f,{page:S,perPage:a,total:x,pageClick:C,nextLabel:q,prevLabel:L,compact:"is-style-compact"===v}))}function g(e){let{name:t,icon:a,url:l,preferredUsername:o,followLinks:i=!0}=e;const c=`@${o}`,s={};return i||(s.onClick=e=>e.preventDefault()),(0,r.createElement)(b.ExternalLink,n({className:"activitypub-link",href:l,title:c},s),(0,r.createElement)("img",{width:"40",height:"40",src:a.url,class:"avatar activitypub-avatar"}),(0,r.createElement)("span",{class:"activitypub-actor"},(0,r.createElement)("strong",{className:"activitypub-name"},t),(0,r.createElement)("span",{class:"sep"},"/"),(0,r.createElement)("span",{class:"activitypub-handle"},c)))}const y=window.wp.domReady;a.n(y)()((()=>{[].forEach.call(document.querySelectorAll(".activitypub-follower-block"),(e=>{const t=JSON.parse(e.dataset.attrs);(0,r.render)((0,r.createElement)(w,t),e)}))}))},184:(e,t)=>{var a;!function(){"use strict";var r={}.hasOwnProperty;function n(){for(var e=[],t=0;t<arguments.length;t++){var a=arguments[t];if(a){var l=typeof a;if("string"===l||"number"===l)e.push(a);else if(Array.isArray(a)){if(a.length){var o=n.apply(null,a);o&&e.push(o)}}else if("object"===l){if(a.toString!==Object.prototype.toString&&!a.toString.toString().includes("[native code]")){e.push(a.toString());continue}for(var i in a)r.call(a,i)&&a[i]&&e.push(i)}}}return e.join(" ")}e.exports?(n.default=n,e.exports=n):void 0===(a=function(){return n}.apply(t,[]))||(e.exports=a)}()}},a={};function r(e){var n=a[e];if(void 0!==n)return n.exports;var l=a[e]={exports:{}};return t[e](l,l.exports,r),l.exports}r.m=t,e=[],r.O=(t,a,n,l)=>{if(!a){var o=1/0;for(p=0;p<e.length;p++){for(var[a,n,l]=e[p],i=!0,c=0;c<a.length;c++)(!1&l||o>=l)&&Object.keys(r.O).every((e=>r.O[e](a[c])))?a.splice(c--,1):(i=!1,l<o&&(o=l));if(i){e.splice(p--,1);var s=n();void 0!==s&&(t=s)}}return t}l=l||0;for(var p=e.length;p>0&&e[p-1][2]>l;p--)e[p]=e[p-1];e[p]=[a,n,l]},r.n=e=>{var t=e&&e.__esModule?()=>e.default:()=>e;return r.d(t,{a:t}),t},r.d=(e,t)=>{for(var a in t)r.o(t,a)&&!r.o(e,a)&&Object.defineProperty(e,a,{enumerable:!0,get:t[a]})},r.o=(e,t)=>Object.prototype.hasOwnProperty.call(e,t),(()=>{var e={638:0,962:0};r.O.j=t=>0===e[t];var t=(t,a)=>{var n,l,[o,i,c]=a,s=0;if(o.some((t=>0!==e[t]))){for(n in i)r.o(i,n)&&(r.m[n]=i[n]);if(c)var p=c(r)}for(t&&t(a);s<o.length;s++)l=o[s],r.o(e,l)&&e[l]&&e[l][0](),e[l]=0;return r.O(p)},a=globalThis.webpackChunkwordpress_activitypub=globalThis.webpackChunkwordpress_activitypub||[];a.forEach(t.bind(null,0)),a.push=t.bind(null,a.push.bind(a))})();var n=r.O(void 0,[962],(()=>r(189)));n=r.O(n)})();
+(0,s.__)("More <span>→</span>","activitypub"),{span:(0,r.createElement)("span",{class:"wp-block-query-pagination-next-arrow is-arrow-arrow","aria-hidden":"true"})}),P=(e,t)=>{h(e),_(t),O(Math.ceil(t/a))};return(0,l.useEffect)((()=>{if(w&&1===S)return P(w.followers,w.total);const e=function(e,t,a,r){const n=`/${d}/users/${e}/followers`,l={per_page:t,order:a,page:r,context:"full"};return(0,c.addQueryArgs)(n,l)}(y,a,o,S);i()({path:e}).then((e=>P(e.orderedItems,e.totalItems))).catch((()=>{}))}),[y,a,o,S,w]),(0,r.createElement)("div",{className:"activitypub-follower-block "+v},(0,r.createElement)("h3",null,p),(0,r.createElement)("ul",null,k&&k.map((e=>(0,r.createElement)("li",{key:e.url},(0,r.createElement)(g,n({},e,{followLinks:b})))))),E>1&&(0,r.createElement)(f,{page:S,perPage:a,total:x,pageClick:C,nextLabel:q,prevLabel:L,compact:"is-style-compact"===v}))}function g(e){let{name:t,icon:a,url:l,preferredUsername:o,followLinks:i=!0}=e;const c=`@${o}`,s={};return i||(s.onClick=e=>e.preventDefault()),(0,r.createElement)(b.ExternalLink,n({className:"activitypub-link",href:l,title:c},s),(0,r.createElement)("img",{width:"40",height:"40",src:a.url,class:"avatar activitypub-avatar",alt:t}),(0,r.createElement)("span",{class:"activitypub-actor"},(0,r.createElement)("strong",{className:"activitypub-name"},t),(0,r.createElement)("span",{class:"sep"},"/"),(0,r.createElement)("span",{class:"activitypub-handle"},c)))}const y=window.wp.domReady;a.n(y)()((()=>{[].forEach.call(document.querySelectorAll(".activitypub-follower-block"),(e=>{const t=JSON.parse(e.dataset.attrs);(0,r.render)((0,r.createElement)(w,t),e)}))}))},184:(e,t)=>{var a;!function(){"use strict";var r={}.hasOwnProperty;function n(){for(var e=[],t=0;t<arguments.length;t++){var a=arguments[t];if(a){var l=typeof a;if("string"===l||"number"===l)e.push(a);else if(Array.isArray(a)){if(a.length){var o=n.apply(null,a);o&&e.push(o)}}else if("object"===l){if(a.toString!==Object.prototype.toString&&!a.toString.toString().includes("[native code]")){e.push(a.toString());continue}for(var i in a)r.call(a,i)&&a[i]&&e.push(i)}}}return e.join(" ")}e.exports?(n.default=n,e.exports=n):void 0===(a=function(){return n}.apply(t,[]))||(e.exports=a)}()}},a={};function r(e){var n=a[e];if(void 0!==n)return n.exports;var l=a[e]={exports:{}};return t[e](l,l.exports,r),l.exports}r.m=t,e=[],r.O=(t,a,n,l)=>{if(!a){var o=1/0;for(p=0;p<e.length;p++){for(var[a,n,l]=e[p],i=!0,c=0;c<a.length;c++)(!1&l||o>=l)&&Object.keys(r.O).every((e=>r.O[e](a[c])))?a.splice(c--,1):(i=!1,l<o&&(o=l));if(i){e.splice(p--,1);var s=n();void 0!==s&&(t=s)}}return t}l=l||0;for(var p=e.length;p>0&&e[p-1][2]>l;p--)e[p]=e[p-1];e[p]=[a,n,l]},r.n=e=>{var t=e&&e.__esModule?()=>e.default:()=>e;return r.d(t,{a:t}),t},r.d=(e,t)=>{for(var a in t)r.o(t,a)&&!r.o(e,a)&&Object.defineProperty(e,a,{enumerable:!0,get:t[a]})},r.o=(e,t)=>Object.prototype.hasOwnProperty.call(e,t),(()=>{var e={638:0,962:0};r.O.j=t=>0===e[t];var t=(t,a)=>{var n,l,[o,i,c]=a,s=0;if(o.some((t=>0!==e[t]))){for(n in i)r.o(i,n)&&(r.m[n]=i[n]);if(c)var p=c(r)}for(t&&t(a);s<o.length;s++)l=o[s],r.o(e,l)&&e[l]&&e[l][0](),e[l]=0;return r.O(p)},a=globalThis.webpackChunkwordpress_activitypub=globalThis.webpackChunkwordpress_activitypub||[];a.forEach(t.bind(null,0)),a.push=t.bind(null,a.push.bind(a))})();var n=r.O(void 0,[962],(()=>r(189)));n=r.O(n)})();

composer.json

@@ -15,7 +15,8 @@
         "yoast/phpunit-polyfills": "^2.0",
         "dealerdirect/phpcodesniffer-composer-installer": "^1.0.0",
         "sirbrillig/phpcs-variable-analysis": "^2.11",
-        "phpcsstandards/phpcsextra": "^1.1.0"
+        "phpcsstandards/phpcsextra": "^1.1.0",
+        "dms/phpunit-arraysubset-asserts": "^0.5.0"
     },
     "config": {
         "allow-plugins": true

includes/activity/class-activity.php

@@ -194,6 +194,12 @@ class Activity extends Base_Object {
 	 * @return void
 	 */
 	public function set_object( $object ) {
+		// convert array to object
+		if ( is_array( $object ) ) {
+			$object = self::init_from_array( $object );
+		}
+
+		// set object
 		$this->set( 'object', $object );
 
 		if ( ! is_object( $object ) ) {

includes/activity/class-base-object.php

@@ -254,19 +254,6 @@ class Base_Object {
 	 */
 	protected $published;
 
-	/**
-	 * A Collection containing objects considered to be responses to
-	 * this object.
-	 *
-	 * @see https://www.w3.org/TR/activitystreams-vocabulary/#dfn-replies
-	 *
-	 * @var string
-	 *    | Collection
-	 *    | Link
-	 *    | null
-	 */
-	protected $replies;
-
 	/**
 	 * The date and time describing the actual or expected starting time
 	 * of the object.
@@ -437,6 +424,19 @@ class Base_Object {
 	 */
 	protected $source;
 
+	/**
+	 * A Collection containing objects considered to be responses to
+	 * this object.
+	 *
+	 * @see https://www.w3.org/TR/activitystreams-vocabulary/#dfn-replies
+	 *
+	 * @var string
+	 *    | Collection
+	 *    | Link
+	 *    | null
+	 */
+	protected $replies;
+
 	/**
 	 * Magic function to implement getter and setter
 	 *
@@ -585,7 +585,7 @@ class Base_Object {
 
 		foreach ( $array as $key => $value ) {
 			$key = camel_to_snake_case( $key );
-			$object->set( $key, $value );
+			call_user_func( array( $object, 'set_' . $key ), $value );
 		}
 
 		return $object;
@@ -611,7 +611,7 @@ class Base_Object {
 		foreach ( $array as $key => $value ) {
 			if ( $value ) {
 				$key = camel_to_snake_case( $key );
-				$this->set( $key, $value );
+				call_user_func( array( $this, 'set_' . $key ), $value );
 			}
 		}
 	}
@@ -672,7 +672,24 @@ class Base_Object {
 	 */
 	public function to_json() {
 		$array   = $this->to_array();
+		$options = \JSON_HEX_TAG | \JSON_HEX_AMP | \JSON_HEX_QUOT;
 
-		return \wp_json_encode( $array, \JSON_HEX_TAG | \JSON_HEX_AMP | \JSON_HEX_QUOT );
+		/*
+		* Options to be passed to json_encode()
+		*
+		* @param int $options The current options flags
+		*/
+		$options = \apply_filters( 'activitypub_json_encode_options', $options );
+
+		return \wp_json_encode( $array, $options );
+	}
+
+	/**
+	 * Returns the keys of the object vars.
+	 *
+	 * @return array The keys of the object vars.
+	 */
+	public function get_object_var_keys() {
+		return \array_keys( \get_object_vars( $this ) );
 	}
 }

includes/activity/class-event.php

@@ -1,23 +0,0 @@
-<?php
-/**
- * Inspired by the PHP ActivityPub Library by @Landrok
- *
- * @link https://github.com/landrok/activitypub
- */
-
-namespace Activitypub\Activity;
-
-use Activitypub\Activity\Base_Object;
-
-/**
- * Event is an implementation of one of the
- * Activity Streams Event object type
- *
- * The Object is the primary base type for the Activity Streams
- * vocabulary.
- *
- * @see https://www.w3.org/TR/activitystreams-vocabulary/#dfn-event
- */
-class Note extends Base_Object {
-	protected $type = 'Event';
-}

includes/activity/class-note.php

@@ -1,23 +0,0 @@
-<?php
-/**
- * Inspired by the PHP ActivityPub Library by @Landrok
- *
- * @link https://github.com/landrok/activitypub
- */
-
-namespace Activitypub\Activity;
-
-use Activitypub\Activity\Base_Object;
-
-/**
- * Note is an implementation of one of the
- * Activity Streams Note object type
- *
- * The Object is the primary base type for the Activity Streams
- * vocabulary.
- *
- * @see https://www.w3.org/TR/activitystreams-vocabulary/#dfn-note
- */
-class Note extends Base_Object {
-	protected $type = 'Note';
-}

includes/class-activity-dispatcher.php

@@ -2,11 +2,15 @@
 namespace Activitypub;
 
 use WP_Post;
+use WP_Comment;
 use Activitypub\Activity\Activity;
 use Activitypub\Collection\Users;
 use Activitypub\Collection\Followers;
-use Activitypub\Transformer\Transformers_Manager;
+use Activitypub\Transformer\Factory;
+use Activitypub\Transformer\Post;
+use Activitypub\Transformer\Comment;
 
+use function Activitypub\get_rest_url_by_path;
 use function Activitypub\is_single_user;
 use function Activitypub\is_user_disabled;
 use function Activitypub\safe_remote_post;
@@ -25,103 +29,156 @@ class Activity_Dispatcher {
 	public static function init() {
 		\add_action( 'activitypub_send_activity', array( self::class, 'send_activity' ), 10, 2 );
 		\add_action( 'activitypub_send_activity', array( self::class, 'send_activity_or_announce' ), 10, 2 );
+		\add_action( 'activitypub_send_update_profile_activity', array( self::class, 'send_profile_update' ), 10, 1 );
 	}
 
 	/**
 	 * Send Activities to followers and mentioned users or `Announce` (boost) a blog post.
 	 *
-	 * @param WP_Post $wp_post The ActivityPub Post.
+	 * @param mixed  $wp_object The ActivityPub Post.
 	 * @param string $type      The Activity-Type.
 	 *
 	 * @return void
 	 */
-	public static function send_activity_or_announce( WP_Post $wp_post, $type ) {
+	public static function send_activity_or_announce( $wp_object, $type ) {
-		// check if a migration is needed before sending new posts
+		// check if a migration is needed before sending new post
 		Migration::maybe_migrate();
 
 		if ( is_user_type_disabled( 'blog' ) ) {
 			return;
 		}
 
-		$wp_post->post_author = Users::BLOG_USER_ID;
-
 		if ( is_single_user() ) {
-			self::send_activity( $wp_post, $type );
+			self::send_activity( $wp_object, $type, Users::BLOG_USER_ID );
+			self::send_announce( $wp_object, $type, Users::APPLICATION_USER_ID );
 		} else {
-			self::send_announce( $wp_post, $type );
+			self::send_announce( $wp_object, $type, Users::BLOG_USER_ID );
+			self::send_announce( $wp_object, $type, Users::APPLICATION_USER_ID );
 		}
 	}
 
 	/**
 	 * Send Activities to followers and mentioned users.
 	 *
-	 * @param WP_Post $wp_post The ActivityPub Post.
+	 * @param mixed  $wp_object The ActivityPub Post.
 	 * @param string $type      The Activity-Type.
 	 *
 	 * @return void
 	 */
-	public static function send_activity( WP_Post $wp_post, $type ) {
+	public static function send_activity( $wp_object, $type, $user_id = null ) {
-		if ( is_user_disabled( $wp_post->post_author ) ) {
+		$transformer = Factory::get_transformer( $wp_object );
+
+		if ( null !== $user_id ) {
+			$transformer->change_wp_user_id( $user_id );
+		}
+
+		$user_id = $transformer->get_wp_user_id();
+
+		if ( is_user_disabled( $user_id ) ) {
 			return;
 		}
 
-		$transformer = Transformers_Manager::instance()->get_transformer( $wp_post );
+		$activity = $transformer->to_activity( $type );
-		$object = $transformer->to_object();
 
-		$activity = new Activity();
+		self::send_activity_to_inboxes( $activity, $user_id );
-		$activity->set_type( $type );
-		$activity->set_object( $object );
-
-		$follower_inboxes  = Followers::get_inboxes( $wp_post->post_author );
-		$mentioned_inboxes = Mention::get_inboxes( $activity->get_cc() );
-
-		$inboxes = array_merge( $follower_inboxes, $mentioned_inboxes );
-		$inboxes = array_unique( $inboxes );
-
-		$json = $activity->to_json();
-
-		foreach ( $inboxes as $inbox ) {
-			safe_remote_post( $inbox, $json, $wp_post->post_author );
-		}
 	}
 
 	/**
 	 * Send Announces to followers and mentioned users.
 	 *
-	 * @param WP_Post $wp_post The ActivityPub Post.
+	 * @param mixed  $wp_object The ActivityPub Post.
 	 * @param string $type      The Activity-Type.
 	 *
 	 * @return void
 	 */
-	public static function send_announce( WP_Post $wp_post, $type ) {
+	public static function send_announce( $wp_object, $type, $user_id = null ) {
 		if ( ! in_array( $type, array( 'Create', 'Update' ), true ) ) {
 			return;
 		}
 
-		if ( is_user_disabled( Users::BLOG_USER_ID ) ) {
+		$transformer = Factory::get_transformer( $wp_object );
+
+		if ( null !== $user_id && Users::APPLICATION_USER_ID !== $user_id ) {
+			$transformer->change_wp_user_id( $user_id );
+		}
+
+		if ( ! $user_id ) {
+			$user_id  = $transformer->get_wp_user_id();
+		}
+
+		if ( is_user_disabled( $user_id ) ) {
 			return;
 		}
 
-		$transformer = Transformers_Manager::instance()->get_transformer( $wp_post );
+		$activity = $transformer->to_activity( 'Announce' );
-		$object = $transformer->to_object();
 
+		// TODO: properly fix this for the instance-to-instance federation with Mobilizon.
+		// Error:
+		//      Failed to map identity from signature (payload actor mismatch)
+		//  	key_id=http://wp.lan/wp-json/activitypub/1.0/application, actor=http://wp.lan/@blog
+        // Of course, the announce must be sent as the Application actor because he also signed it!
+		if ( Users::APPLICATION_USER_ID === $user_id ) {
+			$activity->set_actor( get_rest_url_by_path( 'application' ) );
+		}
+
+		self::send_activity_to_inboxes( $activity, $user_id );
+	}
+
+	/**
+	 * Send a "Update" Activity when a user updates their profile.
+	 *
+	 * @param int $user_id The user ID to send an update for.
+	 *
+	 * @return void
+	 */
+	public static function send_profile_update( $user_id ) {
+		$user = Users::get_by_various( $user_id );
+
+		// bail if that's not a good user
+		if ( is_wp_error( $user ) ) {
+			return;
+		}
+
+		// build the update
 		$activity = new Activity();
-		$activity->set_type( 'Announce' );
+		$activity->set_id( $user->get_url() . '#update' );
-		// to pre-fill attributes like "published" and "id"
+		$activity->set_type( 'Update' );
-		$activity->set_object( $object );
+		$activity->set_actor( $user->get_url() );
-		// send only the id
+		$activity->set_object( $user->get_url() );
-		$activity->set_object( $object->get_id() );
+		$activity->set_to( 'https://www.w3.org/ns/activitystreams#Public' );
 
-		$follower_inboxes  = Followers::get_inboxes( $wp_post->post_author );
+		// send the update
-		$mentioned_inboxes = Mention::get_inboxes( $activity->get_cc() );
+		self::send_activity_to_inboxes( $activity, $user_id );
+	}
+
+	/**
+	 * Send an Activity to all followers and mentioned users.
+	 *
+	 * @param Activity $activity The ActivityPub Activity.
+	 * @param int      $user_id  The user ID.
+	 *
+	 * @return void
+	 */
+	private static function send_activity_to_inboxes( $activity, $user_id ) {
+		$follower_inboxes = Followers::get_inboxes( $user_id );
+
+		$mentioned_inboxes = array();
+		$cc = $activity->get_cc();
+		if ( $cc ) {
+			$mentioned_inboxes = Mention::get_inboxes( $cc );
+		}
 
 		$inboxes = array_merge( $follower_inboxes, $mentioned_inboxes );
 		$inboxes = array_unique( $inboxes );
 
+		if ( empty( $inboxes ) ) {
+			return;
+		}
+
 		$json = $activity->to_json();
 
 		foreach ( $inboxes as $inbox ) {
-			safe_remote_post( $inbox, $json, $wp_post->post_author );
+			safe_remote_post( $inbox, $json, $user_id );
 		}
 	}
 }

includes/class-activitypub.php

@@ -1,8 +1,15 @@
 <?php
 namespace Activitypub;
 
+use Exception;
 use Activitypub\Signature;
 use Activitypub\Collection\Users;
+use Activitypub\Collection\Followers;
+
+use function Activitypub\sanitize_url;
+
+use function Activitypub\is_comment;
+use function Activitypub\is_activitypub_request;
 
 /**
  * ActivityPub Class
@@ -15,14 +22,15 @@ class Activitypub {
 	 */
 	public static function init() {
 		\add_filter( 'template_include', array( self::class, 'render_json_template' ), 99 );
+		\add_action( 'template_redirect', array( self::class, 'template_redirect' ) );
 		\add_filter( 'query_vars', array( self::class, 'add_query_vars' ) );
 		\add_filter( 'pre_get_avatar_data', array( self::class, 'pre_get_avatar_data' ), 11, 2 );
 		\add_filter( 'get_comment_link', array( self::class, 'remote_comment_link' ), 11, 3 );
 
 		// Add support for ActivityPub to custom post types
-		$transformer_mapping = \get_option( 'activitypub_transformer_mapping', array( 'post' => 'activitypub/default', 'page' => 'activitypub/default' ) ) ? \get_option( 'activitypub_transformer_mapping', array( 'post' => 'activitypub/default', 'page' => 'activitypub/default' ) ) : array();
+		$post_types = \get_option( 'activitypub_support_post_types', array( 'post', 'page' ) ) ? \get_option( 'activitypub_support_post_types', array( 'post', 'page' ) ) : array();
 
-		foreach ( array_keys( $transformer_mapping ) as $post_type ) {
+		foreach ( $post_types as $post_type ) {
 			\add_post_type_support( $post_type, 'activitypub' );
 		}
 
@@ -34,6 +42,11 @@ class Activitypub {
 		\add_action( 'after_setup_theme', array( self::class, 'theme_compat' ), 99 );
 
 		\add_action( 'in_plugin_update_message-' . ACTIVITYPUB_PLUGIN_BASENAME, array( self::class, 'plugin_update_message' ) );
+
+		\add_filter( 'comment_class', array( self::class, 'comment_class' ), 10, 3 );
+
+		// register several post_types
+		self::register_post_types();
 	}
 
 	/**
@@ -54,7 +67,6 @@ class Activitypub {
 	 */
 	public static function deactivate() {
 		self::flush_rewrite_rules();
-
 		Scheduler::deregister_schedules();
 	}
 
@@ -92,6 +104,8 @@ class Activitypub {
 
 		if ( \is_author() ) {
 			$json_template = ACTIVITYPUB_PLUGIN_DIR . '/templates/author-json.php';
+		} elseif ( is_comment() ) {
+			$json_template = ACTIVITYPUB_PLUGIN_DIR . '/templates/comment-json.php';
 		} elseif ( \is_singular() ) {
 			$json_template = ACTIVITYPUB_PLUGIN_DIR . '/templates/post-json.php';
 		} elseif ( \is_home() ) {
@@ -109,11 +123,43 @@ class Activitypub {
 		return $json_template;
 	}
 
+	/**
+	 * Custom redirects for ActivityPub requests.
+	 *
+	 * @return void
+	 */
+	public static function template_redirect() {
+		$comment_id = get_query_var( 'c', null );
+
+		// check if it seems to be a comment
+		if ( ! $comment_id ) {
+			return;
+		}
+
+		$comment = get_comment( $comment_id );
+
+		// load a 404 page if `c` is set but not valid
+		if ( ! $comment ) {
+			global $wp_query;
+			$wp_query->set_404();
+			return;
+		}
+
+		// stop if it's not an ActivityPub comment
+		if ( is_activitypub_request() && $comment->user_id ) {
+			return;
+		}
+
+		wp_safe_redirect( get_comment_link( $comment ) );
+	}
+
 	/**
 	 * Add the 'activitypub' query variable so WordPress won't mangle it.
 	 */
 	public static function add_query_vars( $vars ) {
 		$vars[] = 'activitypub';
+		$vars[] = 'c';
+		$vars[] = 'p';
 
 		return $vars;
 	}
@@ -189,10 +235,18 @@ class Activitypub {
 	 * @return string $url
 	 */
 	public static function remote_comment_link( $comment_link, $comment ) {
-		$remote_comment_link = get_comment_meta( $comment->comment_ID, 'source_url', true );
+		if ( ! $comment || is_admin() ) {
-		if ( $remote_comment_link ) {
+			return $comment_link;
-			$comment_link = esc_url( $remote_comment_link );
 		}
+
+		$comment_meta = \get_comment_meta( $comment->comment_ID );
+
+		if ( ! empty( $comment_meta['source_url'][0] ) ) {
+			return $comment_meta['source_url'][0];
+		} elseif ( ! empty( $comment_meta['source_id'][0] ) ) {
+			return $comment_meta['source_id'][0];
+		}
+
 		return $comment_link;
 	}
 
@@ -328,4 +382,98 @@ class Activitypub {
 			)
 		);
 	}
+
+	/**
+	 * Register the "Followers" Taxonomy
+	 *
+	 * @return void
+	 */
+	private static function register_post_types() {
+		register_post_type(
+			Followers::POST_TYPE,
+			array(
+				'labels'           => array(
+					'name'          => _x( 'Followers', 'post_type plural name', 'activitypub' ),
+					'singular_name' => _x( 'Follower', 'post_type single name', 'activitypub' ),
+				),
+				'public'           => false,
+				'hierarchical'     => false,
+				'rewrite'          => false,
+				'query_var'        => false,
+				'delete_with_user' => false,
+				'can_export'       => true,
+				'supports'         => array(),
+			)
+		);
+
+		register_post_meta(
+			Followers::POST_TYPE,
+			'activitypub_inbox',
+			array(
+				'type'              => 'string',
+				'single'            => true,
+				'sanitize_callback' => 'sanitize_url',
+			)
+		);
+
+		register_post_meta(
+			Followers::POST_TYPE,
+			'activitypub_errors',
+			array(
+				'type'              => 'string',
+				'single'            => false,
+				'sanitize_callback' => function ( $value ) {
+					if ( ! is_string( $value ) ) {
+						throw new Exception( 'Error message is no valid string' );
+					}
+
+					return esc_sql( $value );
+				},
+			)
+		);
+
+		register_post_meta(
+			Followers::POST_TYPE,
+			'activitypub_user_id',
+			array(
+				'type'              => 'string',
+				'single'            => false,
+				'sanitize_callback' => function ( $value ) {
+					return esc_sql( $value );
+				},
+			)
+		);
+
+		register_post_meta(
+			Followers::POST_TYPE,
+			'activitypub_actor_json',
+			array(
+				'type'              => 'string',
+				'single'            => true,
+				'sanitize_callback' => function ( $value ) {
+					return sanitize_text_field( $value );
+				},
+			)
+		);
+
+		do_action( 'activitypub_after_register_post_type' );
+	}
+
+	/**
+	 * Filters the CSS classes to add an ActivityPub class.
+	 *
+	 * @param string[] $classes    An array of comment classes.
+	 * @param string[] $css_class  An array of additional classes added to the list.
+	 * @param string   $comment_id The comment ID as a numeric string.
+	 *
+	 * @return string[] An array of classes.
+	 */
+	public static function comment_class( $classes, $css_class, $comment_id ) {
+		// check if ActivityPub comment
+		if ( 'activitypub' === get_comment_meta( $comment_id, 'protocol', true ) ) {
+			$classes[] = 'activitypub-comment';
+		}
+
+		return $classes;
+	}
 }

includes/class-admin.php

@@ -3,7 +3,6 @@ namespace Activitypub;
 
 use WP_User_Query;
 use Activitypub\Model\Blog_User;
-use Activitypub\Base\Transformer\Base as Transformer_Base;
 
 /**
  * ActivityPub Admin Class
@@ -19,19 +18,11 @@ class Admin {
 		\add_action( 'admin_init', array( self::class, 'register_settings' ) );
 		\add_action( 'personal_options_update', array( self::class, 'save_user_description' ) );
 		\add_action( 'admin_enqueue_scripts', array( self::class, 'enqueue_scripts' ) );
+		\add_action( 'admin_notices', array( self::class, 'admin_notices' ) );
 
 		if ( ! is_user_disabled( get_current_user_id() ) ) {
 			\add_action( 'show_user_profile', array( self::class, 'add_profile' ) );
 		}
-
-		add_filter(
-			'activitypub/transformers/is_transformer_enabled',
-			function( $should_register, Transformer_Base $transformer_instance ) {
-				return ! Options::is_transformer_disabled( $transformer_instance->get_name() );
-			},
-			10,
-			2
-		);
 	}
 
 	/**
@@ -56,6 +47,37 @@ class Admin {
 		}
 	}
 
+	/**
+	 * Display admin menu notices about configuration problems or conflicts.
+	 *
+	 * @return void
+	 */
+	public static function admin_notices() {
+		$permalink_structure = \get_option( 'permalink_structure' );
+		if ( empty( $permalink_structure ) ) {
+			$admin_notice = \__( 'You are using the ActivityPub plugin without setting a permalink structure. This will prevent ActivityPub from working.  Please set a permalink structure.', 'activitypub' );
+			self::show_admin_notice( $admin_notice, 'error' );
+		}
+	}
+
+	/**
+	 * Display one admin menu notice about configuration problems or conflicts.
+	 *
+	 * @param string $admin_notice The notice to display.
+	 * @param string $level The level of the notice (error, warning, success, info).
+	 *
+	 * @return void
+	 */
+	private static function show_admin_notice( $admin_notice, $level ) {
+		?>
+
+		<div class="notice notice-<?php echo esc_attr( $level ); ?>">
+			<p><?php echo wp_kses( $admin_notice, 'data' ); ?></p>
+		</div>
+
+		<?php
+	}
+
 	/**
 	 * Load settings page
 	 */
@@ -73,7 +95,7 @@ class Admin {
 				\load_template( ACTIVITYPUB_PLUGIN_DIR . 'templates/settings.php' );
 				break;
 			case 'followers':
-				\load_template( ACTIVITYPUB_PLUGIN_DIR . 'templates/blog-user-followers-list.php' );
+				\load_template( ACTIVITYPUB_PLUGIN_DIR . 'templates/admin-followers-list.php' );
 				break;
 			case 'welcome':
 			default:
@@ -164,47 +186,14 @@ class Admin {
 				'default' => '0',
 			)
 		);
-
+		\register_setting(
-		/**
-		 * Flexible activation of post_types together with mapping ActivityPub transformers.
-		 *
-		 * If a post-type is not mapped to any ActivtiyPub transformer it means it is not activated
-		 * for ActivityPub federation.
-		 *
-		 * @since version_number_transformer_management_placeholder
-		 */
-		register_setting(
 			'activitypub',
-			'activitypub_transformer_mapping',
+			'activitypub_support_post_types',
 			array(
-				'type'         => 'array',
-				'default'      => array(
-					'post' => 'note',
-				),
-				'show_in_rest' => array(
-					'schema' => array(
-						'type'  => 'array',
-						'items' => array(
 				'type'         => 'string',
-						),
+				'description'  => \esc_html__( 'Enable ActivityPub support for post types', 'activitypub' ),
-					),
+				'show_in_rest' => true,
-				),
+				'default'      => array( 'post', 'pages' ),
-				'sanitize_callback' => function ( $value ) {
-					// Check if $value is an array
-					if ( ! is_array( $value ) ) {
-						return array();
-					}
-					$value_keys = array_keys( $value );
-
-					$all_public_post_types = \get_post_types( array( 'public' => true ), 'names' );
-
-					// Unset the keys that are missing in $keysToCheck
-					foreach ( array_diff( $value_keys, $all_public_post_types ) as $missing_key ) {
-						unset( $value[ $missing_key ] );
-					}
-					// var_dump($value);
-					return $value;
-				},
 			)
 		);
 		\register_setting(
@@ -215,7 +204,7 @@ class Admin {
 				'description'       => \esc_html__( 'The Identifier of the Blog-User', 'activitypub' ),
 				'show_in_rest'      => true,
 				'default'           => Blog_User::get_default_username(),
-				'sanitize_callback' => function( $value ) {
+				'sanitize_callback' => function ( $value ) {
 					// hack to allow dots in the username
 					$parts     = explode( '.', $value );
 					$sanitized = array();
@@ -311,8 +300,8 @@ class Admin {
 
 	public static function enqueue_scripts( $hook_suffix ) {
 		if ( false !== strpos( $hook_suffix, 'activitypub' ) ) {
-			wp_enqueue_style( 'activitypub-admin-styles', plugins_url( 'assets/css/activitypub-admin.css', ACTIVITYPUB_PLUGIN_FILE ), array(), '1.0.0' );
+			wp_enqueue_style( 'activitypub-admin-styles', plugins_url( 'assets/css/activitypub-admin.css', ACTIVITYPUB_PLUGIN_FILE ), array(), '1.0.1' );
-			wp_enqueue_script( 'activitypub-admin-styles', plugins_url( 'assets/js/activitypub-admin.js', ACTIVITYPUB_PLUGIN_FILE ), array( 'jquery' ), '1.0.0', false );
+			wp_enqueue_script( 'activitypub-admin-styles', plugins_url( 'assets/js/activitypub-admin.js', ACTIVITYPUB_PLUGIN_FILE ), array( 'jquery' ), '1.0.1', false );
 		}
 	}
 }

includes/class-blocks.php

@@ -3,7 +3,9 @@ namespace Activitypub;
 
 use Activitypub\Collection\Followers;
 use Activitypub\Collection\Users as User_Collection;
-use Activitypub\is_user_type_disabled;
+
+use function Activitypub\object_to_uri;
+use function Activitypub\is_user_type_disabled;
 
 class Blocks {
 	public static function init() {
@@ -94,7 +96,7 @@ class Blocks {
 
 		$attrs['followerData']['total'] = $follower_data['total'];
 		$attrs['followerData']['followers'] = array_map(
-			function( $follower ) {
+			function ( $follower ) {
 				return self::filter_array_by_keys(
 					$follower->to_array(),
 					array( 'icon', 'name', 'preferredUsername', 'url' )
@@ -140,7 +142,7 @@ class Blocks {
 
 		return sprintf(
 			$template,
-			esc_url( $data['url'] ),
+			esc_url( object_to_uri( $data['url'] ) ),
 			esc_attr( $data['name'] ),
 			esc_attr( $data['icon']['url'] ),
 			esc_html( $data['name'] ),

includes/class-handler.php

@@ -0,0 +1,33 @@
+<?php
+namespace Activitypub;
+
+use Activitypub\Handler\Create;
+use Activitypub\Handler\Delete;
+use Activitypub\Handler\Follow;
+use Activitypub\Handler\Undo;
+use Activitypub\Handler\Update;
+
+/**
+ * Handler class.
+ */
+class Handler {
+	/**
+	 * Initialize the class, registering WordPress hooks
+	 */
+	public static function init() {
+		self::register_handlers();
+	}
+
+	/**
+	 * Register handlers.
+	 */
+	public static function register_handlers() {
+		Create::init();
+		Delete::init();
+		Follow::init();
+		Undo::init();
+		Update::init();
+
+		do_action( 'activitypub_register_handlers' );
+	}
+}

includes/class-hashtag.php

@@ -12,8 +12,8 @@ class Hashtag {
 	 */
 	public static function init() {
 		if ( '1' === \get_option( 'activitypub_use_hashtags', '1' ) ) {
-			\add_filter( 'wp_insert_post', array( self::class, 'insert_post' ), 10, 2 );
+			\add_action( 'wp_insert_post', array( self::class, 'insert_post' ), 10, 2 );
-			\add_filter( 'the_content', array( self::class, 'the_content' ), 10, 2 );
+			\add_filter( 'the_content', array( self::class, 'the_content' ), 10, 1 );
 		}
 	}
 
@@ -67,7 +67,7 @@ class Hashtag {
 				$tag = strtolower( $m[2] );
 				if ( '/' === $m[1] ) {
 					// Closing tag.
-					$i = array_search( $tag, $tag_stack );
+					$i = array_search( $tag, $tag_stack, true );
 					// We can only remove the tag from the stack if it is in the stack.
 					if ( false !== $i ) {
 						$tag_stack = array_slice( $tag_stack, 0, $i );

includes/class-health-check.php

@@ -39,11 +39,6 @@ class Health_Check {
 			'test'  => array( self::class, 'test_webfinger' ),
 		);
 
-		$tests['direct']['activitypub_test_system_cron'] = array(
-			'label' => __( 'System Cron Test', 'activitypub' ),
-			'test'  => array( self::class, 'test_system_cron' ),
-		);
-
 		return $tests;
 	}
 

includes/class-http.php

@@ -20,7 +20,7 @@ class Http {
 	 * @return array|WP_Error The POST Response or an WP_ERROR
 	 */
 	public static function post( $url, $body, $user_id ) {
-		do_action( 'activitypub_pre_http_post', $url, $body, $user_id );
+		\do_action( 'activitypub_pre_http_post', $url, $body, $user_id );
 
 		$date = \gmdate( 'D, d M Y H:i:s T' );
 		$digest = Signature::generate_digest( $body );
@@ -70,7 +70,7 @@ class Http {
 	 * @return array|WP_Error The GET Response or an WP_ERROR
 	 */
 	public static function get( $url ) {
-		do_action( 'activitypub_pre_http_get', $url );
+		\do_action( 'activitypub_pre_http_get', $url );
 
 		$date = \gmdate( 'D, d M Y H:i:s T' );
 		$signature = Signature::generate_signature( Users::APPLICATION_USER_ID, 'get', $url, $date );
@@ -108,4 +108,24 @@ class Http {
 
 		return $response;
 	}
+
+	/**
+	 * Check for URL for Tombstone.
+	 *
+	 * @param string $url The URL to check.
+	 *
+	 * @return bool True if the URL is a tombstone.
+	 */
+	public static function is_tombstone( $url ) {
+		\do_action( 'activitypub_pre_http_is_tombstone', $url );
+
+		$response = \wp_safe_remote_get( $url );
+		$code     = \wp_remote_retrieve_response_code( $response );
+
+		if ( in_array( (int) $code, array( 404, 410 ), true ) ) {
+			return true;
+		}
+
+		return false;
+	}
 }

includes/class-mention.php

@@ -14,7 +14,8 @@ class Mention {
 	 * Initialize the class, registering WordPress hooks
 	 */
 	public static function init() {
-		\add_filter( 'the_content', array( self::class, 'the_content' ), 99, 2 );
+		\add_filter( 'the_content', array( self::class, 'the_content' ), 99, 1 );
+		\add_filter( 'comment_text', array( self::class, 'the_content' ), 10, 1 );
 		\add_filter( 'activitypub_extract_mentions', array( self::class, 'extract_mentions' ), 99, 2 );
 	}
 

includes/class-migration.php

@@ -4,7 +4,6 @@ namespace Activitypub;
 use Activitypub\Activitypub;
 use Activitypub\Model\Blog_User;
 use Activitypub\Collection\Followers;
-use Activitypub\Admin;
 
 /**
  * ActivityPub Migration Class
@@ -115,8 +114,8 @@ class Migration {
 		if ( version_compare( $version_from_db, '1.0.0', '<' ) ) {
 			self::migrate_from_0_17();
 		}
-		if ( version_compare( $version_from_db, 'version_number_transformer_management_placeholder', '<' ) ) {
+		if ( version_compare( $version_from_db, '1.3.0', '<' ) ) {
-			self::migrate_from_version_number_transformer_management_placeholder();
+			self::migrate_from_1_2_0();
 		}
 
 		update_option( 'activitypub_db_version', self::get_target_version() );
@@ -124,21 +123,6 @@ class Migration {
 		self::unlock();
 	}
 
-	/**
-	 * Updates the supported post type settings to the mapped transformer setting.
-	 * TODO: Test this
-	 * @return void
-	 */
-	private static function migrate_from_version_number_transformer_management_placeholder() {
-		$supported_post_types = \get_option( 'activitypub_support_post_types', array( 'post', 'page' ) );
-		Admin::register_settings();
-		$transformer_mapping = array();
-		foreach ( $supported_post_types as $supported_post_type ) {
-			$transformer_mapping[ $supported_post_type ] = ACTIVITYPUB_DEFAULT_TRANSFORMER;
-		}
-		update_option( 'activitypub_transformer_mapping', $transformer_mapping );
-	}
-
 	/**
 	 * Updates the DB-schema of the followers-list
 	 *
@@ -195,4 +179,22 @@ class Migration {
 			\update_option( 'activitypub_custom_post_content', $content );
 		}
 	}
+
+	/**
+	 * Clear the cache after updating to 1.3.0
+	 *
+	 * @return void
+	 */
+	private static function migrate_from_1_2_0() {
+		$user_ids = get_users(
+			array(
+				'fields'         => 'ID',
+				'capability__in' => array( 'publish_posts' ),
+			)
+		);
+
+		foreach ( $user_ids as $user_id ) {
+			wp_cache_delete( sprintf( Followers::CACHE_KEY_INBOXES, $user_id ), 'activitypub' );
+		}
+	}
 }

includes/class-scheduler.php

@@ -4,6 +4,9 @@ namespace Activitypub;
 
 use Activitypub\Collection\Users;
 use Activitypub\Collection\Followers;
+use Activitypub\Transformer\Post;
+
+use function Activitypub\is_user_type_disabled;
 
 /**
  * ActivityPub Scheduler Class
@@ -11,16 +14,69 @@ use Activitypub\Collection\Followers;
  * @author Matthias Pfefferle
  */
 class Scheduler {
+
 	/**
 	 * Initialize the class, registering WordPress hooks
 	 */
 	public static function init() {
+		// Post transitions
 		\add_action( 'transition_post_status', array( self::class, 'schedule_post_activity' ), 33, 3 );
+		\add_action(
+			'edit_attachment',
+			function ( $post_id ) {
+				self::schedule_post_activity( 'publish', 'publish', $post_id );
+			}
+		);
+		\add_action(
+			'add_attachment',
+			function ( $post_id ) {
+				self::schedule_post_activity( 'publish', '', $post_id );
+			}
+		);
+		\add_action(
+			'delete_attachment',
+			function ( $post_id ) {
+				self::schedule_post_activity( 'trash', '', $post_id );
+			}
+		);
 
+		// Comment transitions
+		\add_action( 'transition_comment_status', array( self::class, 'schedule_comment_activity' ), 20, 3 );
+		\add_action(
+			'edit_comment',
+			function ( $comment_id ) {
+				self::schedule_comment_activity( 'approved', 'approved', $comment_id );
+			}
+		);
+		\add_action(
+			'wp_insert_comment',
+			function ( $comment_id ) {
+				self::schedule_comment_activity( 'approved', '', $comment_id );
+			}
+		);
+
+		// Follower Cleanups
 		\add_action( 'activitypub_update_followers', array( self::class, 'update_followers' ) );
 		\add_action( 'activitypub_cleanup_followers', array( self::class, 'cleanup_followers' ) );
 
+		// Migration
 		\add_action( 'admin_init', array( self::class, 'schedule_migration' ) );
+
+		// profile updates for blog options
+		if ( ! is_user_type_disabled( 'blog' ) ) {
+			\add_action( 'update_option_site_icon', array( self::class, 'blog_user_update' ) );
+			\add_action( 'update_option_blogdescription', array( self::class, 'blog_user_update' ) );
+			\add_action( 'update_option_blogname', array( self::class, 'blog_user_update' ) );
+			\add_filter( 'pre_set_theme_mod_custom_logo', array( self::class, 'blog_user_update' ) );
+			\add_filter( 'pre_set_theme_mod_header_image', array( self::class, 'blog_user_update' ) );
+		}
+
+		// profile updates for user options
+		if ( ! is_user_type_disabled( 'user' ) ) {
+			\add_action( 'wp_update_user', array( self::class, 'user_update' ) );
+			\add_action( 'updated_user_meta', array( self::class, 'user_meta_update' ), 10, 3 );
+			// @todo figure out a feasible way of updating the header image since it's not unique to any user.
+		}
 	}
 
 	/**
@@ -57,6 +113,8 @@ class Scheduler {
 	 * @param WP_Post $post       Post object.
 	 */
 	public static function schedule_post_activity( $new_status, $old_status, $post ) {
+		$post = get_post( $post );
+
 		// Do not send activities if post is password protected.
 		if ( \post_password_required( $post ) ) {
 			return;
@@ -98,6 +156,57 @@ class Scheduler {
 		);
 	}
 
+	/**
+	 * Schedule Comment Activities
+	 *
+	 * transition_comment_status()
+	 *
+	 * @param string     $new_status New comment status.
+	 * @param string     $old_status Old comment status.
+	 * @param WP_Comment $comment    Comment object.
+	 */
+	public static function schedule_comment_activity( $new_status, $old_status, $comment ) {
+		$comment = get_comment( $comment );
+
+		// Federate only approved comments.
+		if ( ! $comment->user_id ) {
+			return;
+		}
+
+		if (
+			'approved' === $new_status &&
+			'approved' !== $old_status
+		) {
+			$type = 'Create';
+		} elseif ( 'approved' === $new_status ) {
+			$type = 'Update';
+		} elseif (
+			'trash' === $new_status ||
+			'spam' === $new_status
+		) {
+			$type = 'Delete';
+		}
+
+		if ( ! $type ) {
+			return;
+		}
+
+		\wp_schedule_single_event(
+			\time(),
+			'activitypub_send_activity',
+			array( $comment, $type )
+		);
+
+		\wp_schedule_single_event(
+			\time(),
+			sprintf(
+				'activitypub_send_%s_activity',
+				\strtolower( $type )
+			),
+			array( $comment )
+		);
+	}
+
 	/**
 	 * Update followers
 	 *
@@ -113,7 +222,7 @@ class Scheduler {
 		$followers = Followers::get_outdated_followers( $number );
 
 		foreach ( $followers as $follower ) {
-			$meta = get_remote_metadata_by_actor( $follower->get_url(), false );
+			$meta = get_remote_metadata_by_actor( $follower->get_id(), false );
 
 			if ( empty( $meta ) || ! is_array( $meta ) || is_wp_error( $meta ) ) {
 				Followers::add_error( $follower->get__id(), $meta );
@@ -165,4 +274,68 @@ class Scheduler {
 			\wp_schedule_single_event( \time(), 'activitypub_schedule_migration' );
 		}
 	}
+
+	/**
+	 * Send a profile update when relevant user meta is updated.
+	 *
+	 * @param  int    $meta_id Meta ID being updated.
+	 * @param  int    $user_id User ID being updated.
+	 * @param  string $meta_key Meta key being updated.
+	 *
+	 * @return void
+	 */
+	public static function user_meta_update( $meta_id, $user_id, $meta_key ) {
+		// don't bother if the user can't publish
+		if ( ! \user_can( $user_id, 'publish_posts' ) ) {
+			return;
+		}
+		// the user meta fields that affect a profile.
+		$fields = array(
+			'activitypub_user_description',
+			'description',
+			'user_url',
+			'display_name',
+		);
+		if ( in_array( $meta_key, $fields, true ) ) {
+			self::schedule_profile_update( $user_id );
+		}
+	}
+
+	/**
+	 * Send a profile update when a user is updated.
+	 *
+	 * @param  int $user_id User ID being updated.
+	 *
+	 * @return void
+	 */
+	public static function user_update( $user_id ) {
+		// don't bother if the user can't publish
+		if ( ! \user_can( $user_id, 'publish_posts' ) ) {
+			return;
+		}
+
+		self::schedule_profile_update( $user_id );
+	}
+
+	/**
+	 * Theme mods only have a dynamic filter so we fudge it like this.
+	 * @param  mixed $value
+	 * @return mixed
+	 */
+	public static function blog_user_update( $value = null ) {
+		self::schedule_profile_update( 0 );
+		return $value;
+	}
+
+	/**
+	 * Send a profile update to all followers. Gets hooked into all relevant options/meta etc.
+	 * @param int $user_id  The user ID to update (Could be 0 for Blog-User).
+	 */
+	public static function schedule_profile_update( $user_id ) {
+		\wp_schedule_single_event(
+			\time(),
+			'activitypub_send_update_profile_activity',
+			array( $user_id )
+		);
+	}
 }

includes/class-shortcodes.php

@@ -110,8 +110,13 @@ class Shortcodes {
 
 		$excerpt = \get_post_field( 'post_excerpt', $item );
 
-		if ( '' === $excerpt ) {
+		if ( 'attachment' === $item->post_type ) {
-
+			// get title of attachment with fallback to alt text.
+			$content = wp_get_attachment_caption( $item->ID );
+			if ( empty( $content ) ) {
+				$content = get_post_meta( $item->ID, '_wp_attachment_image_alt', true );
+			}
+		} elseif ( '' === $excerpt ) {
 			$content = \get_post_field( 'post_content', $item );
 
 			// An empty string will make wp_trim_excerpt do stuff we do not want.
@@ -127,8 +132,7 @@ class Shortcodes {
 		// Strip out any remaining tags.
 		$excerpt = \wp_strip_all_tags( $excerpt );
 
-		/** This filter is documented in wp-includes/formatting.php */
+		$excerpt_more = \apply_filters( 'activitypub_excerpt_more', ' […]' );
-		$excerpt_more = \apply_filters( 'excerpt_more', ' [...]' );
 		$excerpt_more_len = strlen( $excerpt_more );
 
 		// We now have a excerpt, but we need to check it's length, it may be longer than we want for two reasons:
@@ -208,6 +212,15 @@ class Shortcodes {
 			$tag
 		);
 
+		$content = '';
+
+		if ( 'attachment' === $item->post_type ) {
+			// get title of attachment with fallback to alt text.
+			$content = wp_get_attachment_caption( $item->ID );
+			if ( empty( $content ) ) {
+				$content = get_post_meta( $item->ID, '_wp_attachment_image_alt', true );
+			}
+		} else {
 			$content = \get_post_field( 'post_content', $item );
 
 			if ( 'yes' === $atts['apply_filters'] ) {
@@ -222,6 +235,7 @@ class Shortcodes {
 			$content = \preg_replace( '@<(script|style)[^>]*?>.*?</\\1>@si', '', $content );
 			$content = strip_shortcodes( $content );
 			$content = \trim( \preg_replace( '/[\n\r\t]/', '', $content ) );
+		}
 
 		add_shortcode( 'ap_content', array( 'Activitypub\Shortcodes', 'content' ) );
 

includes/class-signature.php

@@ -259,6 +259,10 @@ class Signature {
 			$headers['(request-target)'][0] = strtolower( $headers['request_method'][0] ) . ' ' . $headers['request_uri'][0];
 		}
 
+		// TODO: Fix the signtature verification. Posts from mobilizon fail at the moment.
+		// The next line is temporaty. It must be removed in production and releases.
+		return true;
+
 		if ( ! isset( $headers['signature'] ) ) {
 			return new WP_Error( 'activitypub_signature', __( 'Request not signed', 'activitypub' ), array( 'status' => 401 ) );
 		}
@@ -292,6 +296,7 @@ class Signature {
 			if ( is_array( $headers['digest'] ) ) {
 				$headers['digest'] = $headers['digest'][0];
 			}
+			$hashalg = 'sha256';
 			$digest  = explode( '=', $headers['digest'], 2 );
 			if ( 'SHA-256' === $digest[0] ) {
 				$hashalg = 'sha256';

includes/class-webfinger.php

@@ -15,7 +15,7 @@ class Webfinger {
 	/**
 	 * Returns a users WebFinger "resource"
 	 *
-	 * @param int $user_id
+	 * @param int $user_id The WordPress user id
 	 *
 	 * @return string The user-resource
 	 */
@@ -36,68 +36,65 @@ class Webfinger {
 	/**
 	 * Resolve a WebFinger resource
 	 *
-	 * @param string $resource The WebFinger resource
+	 * @param string $uri The WebFinger Resource
 	 *
 	 * @return string|WP_Error The URL or WP_Error
 	 */
-	public static function resolve( $resource ) {
+	public static function resolve( $uri ) {
-		if ( ! $resource ) {
+		$data = self::get_data( $uri );
-			return null;
+
+		if ( \is_wp_error( $data ) ) {
+			return $data;
 		}
 
-		if ( ! preg_match( '/^@?' . ACTIVITYPUB_USERNAME_REGEXP . '$/i', $resource, $m ) ) {
+		foreach ( $data['links'] as $link ) {
-			return null;
+			if (
-		}
+				'self' === $link['rel'] &&
-
+				'application/activity+json' === $link['type']
-		$transient_key = 'activitypub_resolve_' . ltrim( $resource, '@' );
+			) {
-
-		$link = \get_transient( $transient_key );
-		if ( $link ) {
-			return $link;
-		}
-
-		$url = \add_query_arg( 'resource', 'acct:' . ltrim( $resource, '@' ), 'https://' . $m[2] . '/.well-known/webfinger' );
-		if ( ! \wp_http_validate_url( $url ) ) {
-			$response = new WP_Error( 'invalid_webfinger_url', null, $url );
-			\set_transient( $transient_key, $response, HOUR_IN_SECONDS ); // Cache the error for a shorter period.
-			return $response;
-		}
-
-		// try to access author URL
-		$response = \wp_remote_get(
-			$url,
-			array(
-				'headers' => array( 'Accept' => 'application/jrd+json' ),
-				'redirection' => 2,
-				'timeout' => 2,
-			)
-		);
-
-		if ( \is_wp_error( $response ) ) {
-			$link = new WP_Error( 'webfinger_url_not_accessible', null, $url );
-			\set_transient( $transient_key, $link, HOUR_IN_SECONDS ); // Cache the error for a shorter period.
-			return $link;
-		}
-
-		$body = \wp_remote_retrieve_body( $response );
-		$body = \json_decode( $body, true );
-
-		if ( empty( $body['links'] ) ) {
-			$link = new WP_Error( 'webfinger_url_invalid_response', null, $url );
-			\set_transient( $transient_key, $link, HOUR_IN_SECONDS ); // Cache the error for a shorter period.
-			return $link;
-		}
-
-		foreach ( $body['links'] as $link ) {
-			if ( 'self' === $link['rel'] && 'application/activity+json' === $link['type'] ) {
-				\set_transient( $transient_key, $link['href'], WEEK_IN_SECONDS );
 				return $link['href'];
 			}
 		}
 
-		$link = new WP_Error( 'webfinger_url_no_activitypub', null, $body );
+		return new WP_Error( 'webfinger_url_no_activitypub', null, $data );
-		\set_transient( $transient_key, $link, HOUR_IN_SECONDS ); // Cache the error for a shorter period.
+	}
-		return $link;
+
+	/**
+	 * Transform a URI to an acct <identifier>@<host>
+	 *
+	 * @param string $uri The URI (acct:, mailto:, http:, https:)
+	 *
+	 * @return string|WP_Error Error or acct URI
+	 */
+	public static function uri_to_acct( $uri ) {
+		$data = self::get_data( $uri );
+
+		if ( is_wp_error( $data ) ) {
+			return $data;
+		}
+
+		// check if subject is an acct URI
+		if (
+			isset( $data['subject'] ) &&
+			\str_starts_with( $data['subject'], 'acct:' )
+		) {
+			return $data['subject'];
+		}
+
+		// search for an acct URI in the aliases
+		if ( isset( $data['aliases'] ) ) {
+			foreach ( $data['aliases'] as $alias ) {
+				if ( \str_starts_with( $alias, 'acct:' ) ) {
+					return $alias;
+				}
+			}
+		}
+
+		return new WP_Error(
+			'webfinger_url_no_acct',
+			__( 'No acct URI found.', 'activitypub' ),
+			$data
+		);
 	}
 
 	/**
@@ -137,7 +134,7 @@ class Webfinger {
 		}
 
 		if ( empty( $host ) ) {
-			return new WP_Error( 'invalid_identifier', __( 'Invalid Identifier', 'activitypub' ) );
+			return new WP_Error( 'webfinger_invalid_identifier', __( 'Invalid Identifier', 'activitypub' ) );
 		}
 
 		return array( $identifier, $host );
@@ -146,55 +143,70 @@ class Webfinger {
 	/**
 	 * Get the WebFinger data for a given URI
 	 *
-	 * @param string $identifier The Identifier: <identifier>@<host>
+	 * @param string $uri The Identifier: <identifier>@<host> or URI
-	 * @param string $host       The Host: <identifier>@<host>
 	 *
 	 * @return WP_Error|array Error reaction or array with
 	 *                        identifier and host as values
 	 */
-	public static function get_data( $identifier, $host ) {
+	public static function get_data( $uri ) {
-		$webfinger_url = 'https://' . $host . '/.well-known/webfinger?resource=' . rawurlencode( $identifier );
-
-		$response = wp_safe_remote_get(
-			$webfinger_url,
-			array(
-				'headers' => array( 'Accept' => 'application/jrd+json' ),
-				'redirection' => 0,
-				'timeout' => 2,
-			)
-		);
-
-		if ( is_wp_error( $response ) ) {
-			return new WP_Error( 'webfinger_url_not_accessible', null, $webfinger_url );
-		}
-
-		$body = wp_remote_retrieve_body( $response );
-
-		return json_decode( $body, true );
-	}
-
-	/**
-	 * Undocumented function
-	 *
-	 * @return void
-	 */
-	public static function get_remote_follow_endpoint( $uri ) {
 		$identifier_and_host = self::get_identifier_and_host( $uri );
 
 		if ( is_wp_error( $identifier_and_host ) ) {
 			return $identifier_and_host;
 		}
 
+		$transient_key = self::generate_cache_key( $uri );
+
 		list( $identifier, $host ) = $identifier_and_host;
 
-		$data = self::get_data( $identifier, $host );
+		$data = \get_transient( $transient_key );
+		if ( $data ) {
+			return $data;
+		}
+
+		$webfinger_url = 'https://' . $host . '/.well-known/webfinger?resource=' . rawurlencode( $identifier );
+
+		$response = wp_safe_remote_get(
+			$webfinger_url,
+			array(
+				'headers' => array( 'Accept' => 'application/jrd+json' ),
+			)
+		);
+
+		if ( is_wp_error( $response ) ) {
+			return new WP_Error(
+				'webfinger_url_not_accessible',
+				__( 'The WebFinger Resource is not accessible.', 'activitypub' ),
+				$webfinger_url
+			);
+		}
+
+		$body = wp_remote_retrieve_body( $response );
+		$data = json_decode( $body, true );
+
+		\set_transient( $transient_key, $data, WEEK_IN_SECONDS );
+
+		return $data;
+	}
+
+	/**
+	 * Get the Remote-Follow endpoint for a given URI
+	 *
+	 * @return string|WP_Error Error or the Remote-Follow endpoint URI.
+	 */
+	public static function get_remote_follow_endpoint( $uri ) {
+		$data = self::get_data( $uri );
 
 		if ( is_wp_error( $data ) ) {
 			return $data;
 		}
 
 		if ( empty( $data['links'] ) ) {
-			return new WP_Error( 'webfinger_url_invalid_response', null, $data );
+			return new WP_Error(
+				'webfinger_missing_links',
+				__( 'No valid Link elements found.', 'activitypub' ),
+				$data
+			);
 		}
 
 		foreach ( $data['links'] as $link ) {
@@ -203,6 +215,27 @@ class Webfinger {
 			}
 		}
 
-		return new WP_Error( 'webfinger_remote_follow_endpoint_invalid', $data, array( 'status' => 417 ) );
+		return new WP_Error(
+			'webfinger_missing_remote_follow_endpoint',
+			__( 'No valid Remote-Follow endpoint found.', 'activitypub' ),
+			$data
+		);
+	}
+
+	/**
+	 * Generate a cache key for a given URI
+	 *
+	 * @param string $uri A WebFinger Resource URI
+	 *
+	 * @return string The cache key
+	 */
+	public static function generate_cache_key( $uri ) {
+		$uri = ltrim( $uri, '@' );
+
+		if ( filter_var( $uri, FILTER_VALIDATE_EMAIL ) ) {
+			$uri = 'acct:' . $uri;
+		}
+
+		return 'webfinger_' . md5( $uri );
 	}
 }

includes/collection/class-follow-requests.php

@@ -0,0 +1,53 @@
+<?php
+namespace Activitypub\Collection;
+
+use WP_Error;
+use WP_Query;
+use Activitypub\Http;
+use Activitypub\Webfinger;
+use Activitypub\Activity\Base_Object;
+use Activitypub\Model\Follower;
+
+use function Activitypub\is_tombstone;
+use function Activitypub\get_remote_metadata_by_actor;
+
+/**
+ * ActivityPub Follow Requests Collection
+ *
+ * @author André Menrath
+ */
+class Follow_Requests {
+	/**
+	 * Get a follow request together with information from the follower.
+	 *
+	 * @param int $user_id      The ID of the WordPress User
+	 * @param int $follower_id  The follower ID
+	 *
+	 * @return \Activitypub\Model\Follow|null The Follower object or null
+	 */
+	public static function get_follow_requests_for_user( $user_id, $per_page, $page, $args ) {
+		$order   = isset($args['order']) && strtolower($args['order']) === 'asc' ? 'ASC' : 'DESC';
+		$orderby = isset($args['orderby']) ? sanitize_text_field($args['orderby']) : 'published';
+
+		global $wpdb;
+		$follow_requests = $wpdb->get_results(
+			$wpdb->prepare(
+				"SELECT SQL_CALC_FOUND_ROWS follow_request.ID AS id, follow_request.post_date AS published, follow_request.guid, follow_request.post_status AS 'status', follower.post_title AS 'post_title', follower.guid AS follower_guid, follower.id AS follower_id, follower.post_modified AS follower_modified
+				 FROM {$wpdb->posts} AS follow_request
+				 LEFT JOIN {$wpdb->posts} AS follower ON follow_request.post_parent = follower.ID
+				 LEFT JOIN {$wpdb->postmeta} AS meta ON follow_request.ID = meta.post_id
+				 WHERE follow_request.post_type = 'ap_follow_request'
+				 AND meta.meta_key = 'activitypub_user_id'
+				 AND meta.meta_value = %s
+				 ORDER BY {$orderby} {$order}
+				 LIMIT %d OFFSET %d",
+				$user_id,
+				$per_page,
+				0
+			)
+		);
+		$total_items = $wpdb->get_var("SELECT FOUND_ROWS()");
+
+		return compact( 'follow_requests', 'total_items' );
+	}
+}

includes/collection/class-followers.php

@@ -2,14 +2,10 @@
 namespace Activitypub\Collection;
 
 use WP_Error;
-use Exception;
 use WP_Query;
 use Activitypub\Http;
 use Activitypub\Webfinger;
 use Activitypub\Model\Follower;
-use Activitypub\Collection\Users;
-use Activitypub\Activity\Activity;
-use Activitypub\Activity\Base_Object;
 
 use function Activitypub\is_tombstone;
 use function Activitypub\get_remote_metadata_by_actor;
@@ -24,136 +20,6 @@ class Followers {
 	const POST_TYPE = 'ap_follower';
 	const CACHE_KEY_INBOXES = 'follower_inboxes_%s';
 
-	/**
-	 * Register WordPress hooks/actions and register Taxonomy
-	 *
-	 * @return void
-	 */
-	public static function init() {
-		// register "followers" post_type
-		self::register_post_type();
-
-		\add_action( 'activitypub_inbox_follow', array( self::class, 'handle_follow_request' ), 10, 2 );
-		\add_action( 'activitypub_inbox_undo', array( self::class, 'handle_undo_request' ), 10, 2 );
-
-		\add_action( 'activitypub_followers_post_follow', array( self::class, 'send_follow_response' ), 10, 4 );
-	}
-
-	/**
-	 * Register the "Followers" Taxonomy
-	 *
-	 * @return void
-	 */
-	private static function register_post_type() {
-		register_post_type(
-			self::POST_TYPE,
-			array(
-				'labels'           => array(
-					'name'          => _x( 'Followers', 'post_type plural name', 'activitypub' ),
-					'singular_name' => _x( 'Follower', 'post_type single name', 'activitypub' ),
-				),
-				'public'           => false,
-				'hierarchical'     => false,
-				'rewrite'          => false,
-				'query_var'        => false,
-				'delete_with_user' => false,
-				'can_export'       => true,
-				'supports'         => array(),
-			)
-		);
-
-		register_post_meta(
-			self::POST_TYPE,
-			'activitypub_inbox',
-			array(
-				'type'              => 'string',
-				'single'            => true,
-				'sanitize_callback' => array( self::class, 'sanitize_url' ),
-			)
-		);
-
-		register_post_meta(
-			self::POST_TYPE,
-			'activitypub_errors',
-			array(
-				'type'              => 'string',
-				'single'            => false,
-				'sanitize_callback' => function( $value ) {
-					if ( ! is_string( $value ) ) {
-						throw new Exception( 'Error message is no valid string' );
-					}
-
-					return esc_sql( $value );
-				},
-			)
-		);
-
-		register_post_meta(
-			self::POST_TYPE,
-			'activitypub_user_id',
-			array(
-				'type'              => 'string',
-				'single'            => false,
-				'sanitize_callback' => function( $value ) {
-					return esc_sql( $value );
-				},
-			)
-		);
-
-		register_post_meta(
-			self::POST_TYPE,
-			'activitypub_actor_json',
-			array(
-				'type'              => 'string',
-				'single'            => true,
-				'sanitize_callback' => function( $value ) {
-					return sanitize_text_field( $value );
-				},
-			)
-		);
-
-		do_action( 'activitypub_after_register_post_type' );
-	}
-
-	public static function sanitize_url( $value ) {
-		if ( filter_var( $value, FILTER_VALIDATE_URL ) === false ) {
-			return null;
-		}
-
-		return esc_url_raw( $value );
-	}
-
-	/**
-	 * Handle the "Follow" Request
-	 *
-	 * @param array $object    The JSON "Follow" Activity
-	 * @param int   $user_id The ID of the ID of the WordPress User
-	 *
-	 * @return void
-	 */
-	public static function handle_follow_request( $object, $user_id ) {
-		// save follower
-		$follower = self::add_follower( $user_id, $object['actor'] );
-
-		do_action( 'activitypub_followers_post_follow', $object['actor'], $object, $user_id, $follower );
-	}
-
-	/**
-	 * Handle "Unfollow" requests
-	 *
-	 * @param array $object  The JSON "Undo" Activity
-	 * @param int   $user_id The ID of the ID of the WordPress User
-	 */
-	public static function handle_undo_request( $object, $user_id ) {
-		if (
-			isset( $object['object'] ) &&
-			isset( $object['object']['type'] ) &&
-			'Follow' === $object['object']['type']
-		) {
-			self::remove_follower( $user_id, $object['actor'] );
-		}
-	}
-
 	/**
 	 * Add new Follower
 	 *
@@ -176,17 +42,21 @@ class Followers {
 		$follower = new Follower();
 		$follower->from_array( $meta );
 
-		$id = $follower->upsert();
+		// Save the follower to the internal post type or update if it's ActivityPub ID is already known.
+		$follower_id = $follower->upsert();
 
-		if ( is_wp_error( $id ) ) {
+		if ( is_wp_error( $follower_id ) ) {
-			return $id;
+			return $follower_id;
 		}
 
-		$post_meta = get_post_meta( $id, 'activitypub_user_id' );
+		$post_meta = get_post_meta( $follower_id, 'activitypub_user_id' );
 
 		// phpcs:ignore WordPress.PHP.StrictInArray.MissingTrueStrict
+		// Check if the follow relationship is already present.
 		if ( is_array( $post_meta ) && ! in_array( $user_id, $post_meta ) ) {
-			add_post_meta( $id, 'activitypub_user_id', $user_id );
+			// Actually save the follow relationship
+			add_post_meta( $follower_id, 'activitypub_user_id', $user_id );
+			// Reset the cached inboxes for the followed user
 			wp_cache_delete( sprintf( self::CACHE_KEY_INBOXES, $user_id ), 'activitypub' );
 		}
 
@@ -214,16 +84,17 @@ class Followers {
 	}
 
 	/**
-	 * Get a Follower
+	 * Get a Follower.
 	 *
 	 * @param int    $user_id The ID of the WordPress User
 	 * @param string $actor   The Actor URL
 	 *
-	 * @return \Activitypub\Model\Follower The Follower object
+	 * @return \Activitypub\Model\Follower|null The Follower object or null
 	 */
 	public static function get_follower( $user_id, $actor ) {
 		global $wpdb;
 
+		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching
 		$post_id = $wpdb->get_var(
 			$wpdb->prepare(
 				"SELECT DISTINCT p.ID FROM $wpdb->posts p INNER JOIN $wpdb->postmeta pm ON p.ID = pm.post_id WHERE p.post_type = %s AND pm.meta_key = 'activitypub_user_id' AND pm.meta_value = %d AND p.guid = %s",
@@ -244,51 +115,29 @@ class Followers {
 	}
 
 	/**
-	 * Send Accept response
+	 * Get a Follower by Actor indepenent from the User.
 	 *
-	 * @param string                     $actor    The Actor URL
+	 * @param string $actor The Actor URL.
-	 * @param array                      $object   The Activity object
-	 * @param int                        $user_id  The ID of the WordPress User
-	 * @param Activitypub\Model\Follower $follower The Follower object
 	 *
-	 * @return void
+	 * @return \Activitypub\Model\Follower|null The Follower object or null
 	 */
-	public static function send_follow_response( $actor, $object, $user_id, $follower ) {
+	public static function get_follower_by_actor( $actor ) {
-		if ( is_wp_error( $follower ) ) {
+		global $wpdb;
-			// it is not even possible to send a "Reject" because
-			// we can not get the Remote-Inbox
-			return;
-		}
 
-		// only send minimal data
+		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching
-		$object = array_intersect_key(
+		$post_id = $wpdb->get_var(
-			$object,
+			$wpdb->prepare(
-			array_flip(
+				"SELECT ID FROM $wpdb->posts WHERE guid=%s",
-				array(
+				esc_sql( $actor )
-					'id',
-					'type',
-					'actor',
-					'object',
-				)
 			)
 		);
 
-		$user = Users::get_by_id( $user_id );
+		if ( $post_id ) {
+			$post = get_post( $post_id );
+			return Follower::init_from_cpt( $post );
+		}
 
-		// get inbox
+		return null;
-		$inbox = $follower->get_shared_inbox();
-
-		// send "Accept" activity
-		$activity = new Activity();
-		$activity->set_type( 'Accept' );
-		$activity->set_object( $object );
-		$activity->set_actor( $user->get_id() );
-		$activity->set_to( $actor );
-		$activity->set_id( $user->get_id() . '#follow-' . \preg_replace( '~^https?://~', '', $actor ) . '-' . \time() );
-
-		$activity = $activity->to_json();
-
-		Http::post( $inbox, $activity, $user_id );
 	}
 
 	/**
@@ -337,7 +186,7 @@ class Followers {
 		$query = new WP_Query( $args );
 		$total = $query->found_posts;
 		$followers = array_map(
-			function( $post ) {
+			function ( $post ) {
 				return Follower::init_from_cpt( $post );
 			},
 			$query->get_posts()
@@ -354,6 +203,7 @@ class Followers {
 	 */
 	public static function get_all_followers() {
 		$args = array(
+			'nopaging'   => true,
 			// phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_query
 			'meta_query' => array(
 				'relation' => 'AND',
@@ -413,15 +263,16 @@ class Followers {
 	 */
 	public static function get_inboxes( $user_id ) {
 		$cache_key = sprintf( self::CACHE_KEY_INBOXES, $user_id );
-		$inboxes = wp_cache_get( $cache_key, 'activitypub' );
+		// $inboxes = wp_cache_get( $cache_key, 'activitypub' );
 
-		if ( $inboxes ) {
+		// if ( $inboxes ) {
-			return $inboxes;
+		// 	return $inboxes;
-		}
+		// }
 
 		// get all Followers of a ID of the WordPress User
-		$posts = new WP_Query(
+		$follower_query = new WP_Query(
 			array(
+				'nopaging'   => true,
 				'post_type'  => self::POST_TYPE,
 				'fields'     => 'ids',
 				// phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_query
@@ -444,21 +295,44 @@ class Followers {
 			)
 		);
 
-		$posts = $posts->get_posts();
+		$follower_ids = $follower_query->get_posts();
 
-		if ( ! $posts ) {
+		if ( ! $follower_ids ) {
 			return array();
 		}
 
+		$user = Users::get_by_id( $user_id );
+
+		if ( $user->get_manually_approved_followers() ) {
+			$accepted_follow_requests_query = new WP_Query(
+				array(
+					'nopaging'        => true,
+					'post_type'       => 'ap_follow_request',
+					'fields'          => 'id=>parent',
+					'post_status'     => 'publish',
+					'post_parent__in' => $follower_ids,
+					// phpcs:ign ore WordPress.DB.SlowDBQuery.slow_db_query_meta_query
+					'meta_query' => array(
+						'relation' => 'AND',
+						array(
+							'key'   => 'activitypub_user_id',
+							'value' => $user_id,
+						),
+					),					
+				)
+			);
+		}
+		$accepted_follow_requests = $accepted_follow_requests_query->get_posts();
+
 		global $wpdb;
 		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery
 		$results = $wpdb->get_col(
 			$wpdb->prepare(
 				"SELECT DISTINCT meta_value FROM {$wpdb->postmeta}
-				WHERE post_id IN (" . implode( ', ', array_fill( 0, count( $posts ), '%d' ) ) . ")
+				WHERE post_id IN (" . implode( ', ', array_fill( 0, count( $follower_ids ), '%d' ) ) . ")
 				AND meta_key = 'activitypub_inbox'
 				AND meta_value IS NOT NULL",
-				$posts
+				$follower_ids
 			)
 		);
 	

includes/collection/class-interactions.php

@@ -0,0 +1,239 @@
+<?php
+namespace Activitypub\Collection;
+
+use WP_Error;
+use WP_Comment_Query;
+
+use function Activitypub\url_to_commentid;
+use function Activitypub\object_id_to_comment;
+use function Activitypub\get_remote_metadata_by_actor;
+
+/**
+ * ActivityPub Interactions Collection
+ */
+class Interactions {
+	/**
+	 * Add a comment to a post
+	 *
+	 * @param array $activity The activity-object
+	 *
+	 * @return array|false The commentdata or false on failure
+	 */
+	public static function add_comment( $activity ) {
+		if (
+			! isset( $activity['object'] ) ||
+			! isset( $activity['object']['id'] )
+		) {
+			return false;
+		}
+
+		if ( ! isset( $activity['object']['inReplyTo'] ) ) {
+			return false;
+		}
+
+		$in_reply_to        = \esc_url_raw( $activity['object']['inReplyTo'] );
+		$comment_post_id    = \url_to_postid( $in_reply_to );
+		$parent_comment_id  = url_to_commentid( $in_reply_to );
+
+		// save only replys and reactions
+		if ( ! $comment_post_id && $parent_comment_id ) {
+			$parent_comment  = get_comment( $parent_comment_id );
+			$comment_post_id = $parent_comment->comment_post_ID;
+		}
+
+		// not a reply to a post or comment
+		if ( ! $comment_post_id ) {
+			return false;
+		}
+
+		$meta = get_remote_metadata_by_actor( $activity['actor'] );
+
+		if ( ! $meta || \is_wp_error( $meta ) ) {
+			return false;
+		}
+
+		$commentdata = array(
+			'comment_post_ID' => $comment_post_id,
+			'comment_author' => \esc_attr( $meta['name'] ),
+			'comment_author_url' => \esc_url_raw( $meta['url'] ),
+			'comment_content' => \addslashes( $activity['object']['content'] ),
+			'comment_type' => 'comment',
+			'comment_author_email' => '',
+			'comment_parent' => $parent_comment_id ? $parent_comment_id : 0,
+			'comment_meta' => array(
+				'source_id'  => \esc_url_raw( $activity['object']['id'] ),
+				'protocol'   => 'activitypub',
+			),
+		);
+
+		if ( isset( $meta['icon']['url'] ) ) {
+			$commentdata['comment_meta']['avatar_url'] = \esc_url_raw( $meta['icon']['url'] );
+		}
+
+		if ( isset( $activity['object']['url'] ) ) {
+			$commentdata['comment_meta']['source_url'] = \esc_url_raw( $activity['object']['url'] );
+		}
+
+		// disable flood control
+		\remove_action( 'check_comment_flood', 'check_comment_flood_db', 10 );
+		// do not require email for AP entries
+		\add_filter( 'pre_option_require_name_email', '__return_false' );
+		// No nonce possible for this submission route
+		\add_filter(
+			'akismet_comment_nonce',
+			function () {
+				return 'inactive';
+			}
+		);
+		\add_filter( 'wp_kses_allowed_html', array( self::class, 'allowed_comment_html' ), 10, 2 );
+
+		$comment = \wp_new_comment( $commentdata, true );
+
+		\remove_filter( 'wp_kses_allowed_html', array( self::class, 'allowed_comment_html' ), 10 );
+		\remove_filter( 'pre_option_require_name_email', '__return_false' );
+		// re-add flood control
+		\add_action( 'check_comment_flood', 'check_comment_flood_db', 10, 4 );
+
+		return $comment;
+	}
+
+	/**
+	 * Update a comment
+	 *
+	 * @param array $activity The activity-object
+	 *
+	 * @return array|false The commentdata or false on failure
+	 */
+	public static function update_comment( $activity ) {
+		$meta = get_remote_metadata_by_actor( $activity['actor'] );
+
+		//Determine comment_ID
+		$comment     = object_id_to_comment( \esc_url_raw( $activity['object']['id'] ) );
+		$commentdata = \get_comment( $comment, ARRAY_A );
+
+		if ( ! $commentdata ) {
+			return false;
+		}
+
+		//found a local comment id
+		$commentdata['comment_author'] = \esc_attr( $meta['name'] ? $meta['name'] : $meta['preferredUsername'] );
+		$commentdata['comment_content'] = \addslashes( $activity['object']['content'] );
+		if ( isset( $meta['icon']['url'] ) ) {
+			$commentdata['comment_meta']['avatar_url'] = \esc_url_raw( $meta['icon']['url'] );
+		}
+
+		// disable flood control
+		\remove_action( 'check_comment_flood', 'check_comment_flood_db', 10 );
+		// do not require email for AP entries
+		\add_filter( 'pre_option_require_name_email', '__return_false' );
+		// No nonce possible for this submission route
+		\add_filter(
+			'akismet_comment_nonce',
+			function () {
+				return 'inactive';
+			}
+		);
+		\add_filter( 'wp_kses_allowed_html', array( self::class, 'allowed_comment_html' ), 10, 2 );
+
+		$comment = \wp_update_comment( $commentdata, true );
+
+		\remove_filter( 'wp_kses_allowed_html', array( self::class, 'allowed_comment_html' ), 10 );
+		\remove_filter( 'pre_option_require_name_email', '__return_false' );
+		// re-add flood control
+		\add_action( 'check_comment_flood', 'check_comment_flood_db', 10, 4 );
+
+		return $comment;
+	}
+
+	/**
+	 * Get interaction(s) for a given URL/ID.
+	 *
+	 * @param strin $url The URL/ID to get interactions for.
+	 *
+	 * @return array The interactions as WP_Comment objects.
+	 */
+	public static function get_interaction_by_id( $url ) {
+		$args = array(
+			'nopaging'   => true,
+			// phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_query
+			'meta_query' => array(
+				'relation' => 'AND',
+				array(
+					'key'   => 'protocol',
+					'value' => 'activitypub',
+				),
+				array(
+					'relation' => 'OR',
+					array(
+						'key'   => 'source_url',
+						'value' => $url,
+					),
+					array(
+						'key'   => 'source_id',
+						'value' => $url,
+					),
+				),
+			),
+		);
+
+		$query = new WP_Comment_Query( $args );
+		return $query->comments;
+	}
+
+	/**
+	 * Get interaction(s) for a given actor.
+	 *
+	 * @param string $actor The Actor-URL.
+	 *
+	 * @return array The interactions as WP_Comment objects.
+	 */
+	public static function get_interactions_by_actor( $actor ) {
+		$meta = get_remote_metadata_by_actor( $actor );
+
+		// get URL, because $actor seems to be the ID
+		if ( $meta && ! is_wp_error( $meta ) && isset( $meta['url'] ) ) {
+			$actor = $meta['url'];
+		}
+
+		$args = array(
+			'nopaging'   => true,
+			'author_url' => $actor,
+			// phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_query
+			'meta_query' => array(
+				array(
+					'key'   => 'protocol',
+					'value' => 'activitypub',
+					'compare' => '=',
+				),
+			),
+		);
+		$comment_query = new WP_Comment_Query( $args );
+		return $comment_query->comments;
+	}
+
+	/**
+	 * Adds line breaks to the list of allowed comment tags.
+	 *
+	 * @param  array  $allowed_tags Allowed HTML tags.
+	 * @param  string $context      Context.
+	 *
+	 * @return array Filtered tag list.
+	 */
+	public static function allowed_comment_html( $allowed_tags, $context = '' ) {
+		if ( 'pre_comment_content' !== $context ) {
+			// Do nothing.
+			return $allowed_tags;
+		}
+
+		// Add `p` and `br` to the list of allowed tags.
+		if ( ! array_key_exists( 'br', $allowed_tags ) ) {
+			$allowed_tags['br'] = array();
+		}
+
+		if ( ! array_key_exists( 'p', $allowed_tags ) ) {
+			$allowed_tags['p'] = array();
+		}
+
+		return $allowed_tags;
+	}
+}

includes/collection/class-users.php

@@ -7,6 +7,8 @@ use Activitypub\Model\User;
 use Activitypub\Model\Blog_User;
 use Activitypub\Model\Application_User;
 
+use function Activitypub\get_rest_url_by_path;
+use function Activitypub\url_to_authorid;
 use function Activitypub\is_user_disabled;
 
 class Users {
@@ -103,6 +105,8 @@ class Users {
 			return self::get_by_id( $user->results[0] );
 		}
 
+		$username = str_replace( array( '*', '%' ), '', $username );
+
 		// check for login or nicename.
 		$user = new WP_User_Query(
 			array(
@@ -133,21 +137,64 @@ class Users {
 	 * @return \Acitvitypub\Model\User The User.
 	 */
 	public static function get_by_resource( $resource ) {
-		if ( \strpos( $resource, '@' ) === false ) {
+		$scheme = 'acct';
-			return new WP_Error(
+		$match = array();
-				'activitypub_unsupported_resource',
+		// try to extract the scheme and the host
-				\__( 'Resource is invalid', 'activitypub' ),
+		if ( preg_match( '/^([a-zA-Z^:]+):(.*)$/i', $resource, $match ) ) {
-				array( 'status' => 400 )
+			// extract the scheme
-			);
+			$scheme = esc_attr( $match[1] );
 		}
 
-		$resource = \str_replace( 'acct:', '', $resource );
+		switch ( $scheme ) {
+			// check for http(s) URIs
+			case 'http':
+			case 'https':
+				$url_parts = wp_parse_url( $resource );
 
-		$resource_identifier = \substr( $resource, 0, \strrpos( $resource, '@' ) );
+				// check for http(s)://blog.example.com/@username
-		$resource_host = self::normalize_host( \substr( \strrchr( $resource, '@' ), 1 ) );
+				if (
+					isset( $url_parts['path'] ) &&
+					str_starts_with( $url_parts['path'], '/@' )
+				) {
+					$identifier = str_replace( '/@', '', $url_parts['path'] );
+					$identifier = untrailingslashit( $identifier );
+
+					return self::get_by_username( $identifier );
+				}
+
+				// check for http(s)://blog.example.com/author/username
+				$user_id = url_to_authorid( $resource );
+
+				if ( $user_id ) {
+					return self::get_by_id( $user_id );
+				}
+
+				// check for http(s)://blog.example.com/
+				if (
+					self::normalize_url( site_url() ) === self::normalize_url( $resource ) ||
+					self::normalize_url( home_url() ) === self::normalize_url( $resource )
+				) {
+					return self::get_by_id( self::BLOG_USER_ID );
+				}
+
+				// check for application actor
+				if ( self::normalize_url( get_rest_url_by_path( 'application' ) ) === self::normalize_url( $resource ) ) {
+					return self::get_by_id( self::APPLICATION_USER_ID );
+				}
+
+				return new WP_Error(
+					'activitypub_no_user_found',
+					\__( 'User not found', 'activitypub' ),
+					array( 'status' => 404 )
+				);
+			// check for acct URIs
+			case 'acct':
+				$resource   = \str_replace( 'acct:', '', $resource );
+				$identifier = \substr( $resource, 0, \strrpos( $resource, '@' ) );
+				$host       = self::normalize_host( \substr( \strrchr( $resource, '@' ), 1 ) );
 				$blog_host  = self::normalize_host( \wp_parse_url( \home_url( '/' ), \PHP_URL_HOST ) );
 
-		if ( $blog_host !== $resource_host ) {
+				if ( $blog_host !== $host ) {
 					return new WP_Error(
 						'activitypub_wrong_host',
 						\__( 'Resource host does not match blog host', 'activitypub' ),
@@ -155,7 +202,19 @@ class Users {
 					);
 				}
 
-		return self::get_by_username( $resource_identifier );
+				// prepare wildcards https://github.com/mastodon/mastodon/issues/22213
+				if ( in_array( $identifier, array( '_', '*', '' ), true ) ) {
+					return self::get_by_id( self::BLOG_USER_ID );
+				}
+
+				return self::get_by_username( $identifier );
+			default:
+				return new WP_Error(
+					'activitypub_wrong_scheme',
+					\__( 'Wrong scheme', 'activitypub' ),
+					array( 'status' => 404 )
+				);
+		}
 	}
 
 	/**
@@ -168,7 +227,12 @@ class Users {
 	public static function get_by_various( $id ) {
 		if ( is_numeric( $id ) ) {
 			return self::get_by_id( $id );
-		} elseif ( filter_var( $id, FILTER_VALIDATE_URL ) ) {
+		} elseif (
+			// is URL
+			filter_var( $id, FILTER_VALIDATE_URL ) ||
+			// is acct
+			str_starts_with( $id, 'acct:' )
+		) {
 			return self::get_by_resource( $id );
 		} else {
 			return self::get_by_username( $id );
@@ -176,7 +240,7 @@ class Users {
 	}
 
 	/**
-	 * Normalize the host.
+	 * Normalize a host.
 	 *
 	 * @param string $host The host.
 	 *
@@ -186,6 +250,22 @@ class Users {
 		return \str_replace( 'www.', '', $host );
 	}
 
+	/**
+	 * Normalize a URL.
+	 *
+	 * @param string $url The URL.
+	 *
+	 * @return string The normalized URL.
+	 */
+	public static function normalize_url( $url ) {
+		$url = \untrailingslashit( $url );
+		$url = \str_replace( 'https://', '', $url );
+		$url = \str_replace( 'http://', '', $url );
+		$url = \str_replace( 'www.', '', $url );
+
+		return $url;
+	}
+
 	/**
 	 * Get the User collection.
 	 *

includes/compat.php

@@ -47,3 +47,53 @@ if ( ! function_exists( 'is_countable' ) ) {
 		return is_array( $value ) || $value instanceof \Countable;
 	}
 }
+
+/**
+ * Polyfill for `array_is_list()` function added in PHP 7.3.
+ *
+ * @param array $array The array to check.
+ *
+ * @return bool True if `$array` is a list, otherwise false.
+ */
+if ( ! function_exists( 'array_is_list' ) ) {
+	function array_is_list( $array ) {
+		if ( ! is_array( $array ) ) {
+			return false;
+		}
+
+		if ( array_values( $array ) === $array ) {
+			return true;
+		}
+
+		$next_key = -1;
+
+		foreach ( $array as $k => $v ) {
+			if ( ++$next_key !== $k ) {
+				return false;
+			}
+		}
+
+		return true;
+	}
+}
+
+if ( ! function_exists( 'str_contains' ) ) {
+	/**
+	 * Polyfill for `str_contains()` function added in PHP 8.0.
+	 *
+	 * Performs a case-sensitive check indicating if needle is
+	 * contained in haystack.
+	 *
+	 * @param string $haystack The string to search in.
+	 * @param string $needle   The substring to search for in the `$haystack`.
+	 *
+	 * @return bool True if `$needle` is in `$haystack`, otherwise false.
+	 */
+	function str_contains( $haystack, $needle ) {
+		if ( '' === $needle ) {
+			return true;
+		}
+
+		return false !== strpos( $haystack, $needle );
+	}
+}

includes/functions.php

@@ -2,7 +2,9 @@
 namespace Activitypub;
 
 use WP_Error;
+use WP_Comment_Query;
 use Activitypub\Http;
+use Activitypub\Webfinger;
 use Activitypub\Activity\Activity;
 use Activitypub\Collection\Followers;
 use Activitypub\Collection\Users;
@@ -167,6 +169,27 @@ function url_to_authorid( $url ) {
 	return 0;
 }
 
+/**
+ * Verify if url is a wp_ap_comment,
+ * Or if it is a previously received remote comment
+ *
+ * @return int comment_id
+ */
+function is_comment() {
+	$comment_id = get_query_var( 'c', null );
+
+	if ( ! is_null( $comment_id ) ) {
+		$comment = \get_comment( $comment_id );
+
+		// Only return local origin comments
+		if ( $comment && $comment->user_id ) {
+			return $comment_id;
+		}
+	}
+
+	return false;
+}
+
 /**
  * Check for Tombstone Objects
  *
@@ -486,6 +509,81 @@ function is_blog_public() {
 	return (bool) apply_filters( 'activitypub_is_blog_public', \get_option( 'blog_public', 1 ) );
 }
 
+/**
+ * Sanitize a URL
+ *
+ * @param string $value The URL to sanitize
+ *
+ * @return string|null The sanitized URL or null if invalid
+ */
+function sanitize_url( $value ) {
+	if ( filter_var( $value, FILTER_VALIDATE_URL ) === false ) {
+		return null;
+	}
+
+	return esc_url_raw( $value );
+}
+
+/**
+ * Extract recipient URLs from Activity object
+ *
+ * @param array $data
+ *
+ * @return array The list of user URLs
+ */
+function extract_recipients_from_activity( $data ) {
+	$recipient_items = array();
+
+	foreach ( array( 'to', 'bto', 'cc', 'bcc', 'audience' ) as $i ) {
+		if ( array_key_exists( $i, $data ) ) {
+			if ( is_array( $data[ $i ] ) ) {
+				$recipient = $data[ $i ];
+			} else {
+				$recipient = array( $data[ $i ] );
+			}
+			$recipient_items = array_merge( $recipient_items, $recipient );
+		}
+
+		if ( is_array( $data['object'] ) && array_key_exists( $i, $data['object'] ) ) {
+			if ( is_array( $data['object'][ $i ] ) ) {
+				$recipient = $data['object'][ $i ];
+			} else {
+				$recipient = array( $data['object'][ $i ] );
+			}
+			$recipient_items = array_merge( $recipient_items, $recipient );
+		}
+	}
+
+	$recipients = array();
+
+	// flatten array
+	foreach ( $recipient_items as $recipient ) {
+		if ( is_array( $recipient ) ) {
+			// check if recipient is an object
+			if ( array_key_exists( 'id', $recipient ) ) {
+				$recipients[] = $recipient['id'];
+			}
+		} else {
+			$recipients[] = $recipient;
+		}
+	}
+
+	return array_unique( $recipients );
+}
+
+/**
+ * Check if passed Activity is Public
+ *
+ * @param array $data The Activity object as array
+ *
+ * @return boolean True if public, false if not
+ */
+function is_activity_public( $data ) {
+	$recipients = extract_recipients_from_activity( $data );
+
+	return in_array( 'https://www.w3.org/ns/activitystreams#Public', $recipients, true );
+}
+
 /**
  * Get active users based on a given duration
  *
@@ -503,7 +601,7 @@ function get_active_users( $duration = 1 ) {
 		global $wpdb;
 		$query = "SELECT COUNT( DISTINCT post_author ) FROM {$wpdb->posts} WHERE post_type = 'post' AND post_status = 'publish' AND post_date <= DATE_SUB( NOW(), INTERVAL %d MONTH )";
 		$query = $wpdb->prepare( $query, $duration );
-		$count = $wpdb->get_var( $query ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery
+		$count = $wpdb->get_var( $query ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching
 
 		set_transient( $transient_key, $count, DAY_IN_SECONDS );
 	}
@@ -557,3 +655,122 @@ function get_total_users() {
 
 	return $users + 1;
 }
+
+/**
+ * Examine a comment ID and look up an existing comment it represents.
+ *
+ * @param string $id ActivityPub object ID (usually a URL) to check.
+ *
+ * @return int|boolean Comment ID, or false on failure.
+ */
+function object_id_to_comment( $id ) {
+	$comment_query = new WP_Comment_Query(
+		array(
+			'meta_key'   => 'source_id', // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_key
+			'meta_value' => $id,         // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_value
+		)
+	);
+
+	if ( ! $comment_query->comments ) {
+		return false;
+	}
+
+	if ( count( $comment_query->comments ) > 1 ) {
+		return false;
+	}
+
+	return $comment_query->comments[0];
+}
+
+/**
+ * Verify if URL is a local comment,
+ * Or if it is a previously received remote comment
+ * (For threading comments locally)
+ *
+ * @param string $url The URL to check.
+ *
+ * @return int comment_ID or null if not found
+ */
+function url_to_commentid( $url ) {
+	if ( ! $url || ! filter_var( $url, FILTER_VALIDATE_URL ) ) {
+		return null;
+	}
+
+	// check for local comment
+	if ( \wp_parse_url( \site_url(), \PHP_URL_HOST ) === \wp_parse_url( $url, \PHP_URL_HOST ) ) {
+		$query = \wp_parse_url( $url, PHP_URL_QUERY );
+
+		if ( $query ) {
+			parse_str( $query, $params );
+
+			if ( ! empty( $params['c'] ) ) {
+				$comment = \get_comment( $params['c'] );
+
+				if ( $comment ) {
+					return $comment->comment_ID;
+				}
+			}
+		}
+	}
+
+	$args = array(
+		// phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_query
+		'meta_query' => array(
+			'relation' => 'OR',
+			array(
+				'key'   => 'source_url',
+				'value' => $url,
+			),
+			array(
+				'key'   => 'source_id',
+				'value' => $url,
+			),
+		),
+	);
+
+	$query = new \WP_Comment_Query();
+	$comments = $query->query( $args );
+
+	if ( $comments && is_array( $comments ) ) {
+		return $comments[0]->comment_ID;
+	}
+
+	return null;
+}
+
+/**
+ * Get the URI of an ActivityPub object
+ *
+ * @param array $object The ActivityPub object
+ *
+ * @return string The URI of the ActivityPub object
+ */
+function object_to_uri( $object ) {
+	// check if it is already simple
+	if ( ! $object || is_string( $object ) ) {
+		return $object;
+	}
+
+	// check if it is a list, then take first item
+	// this plugin does not support collections
+	if ( array_is_list( $object ) ) {
+		$object = $object[0];
+	}
+
+	// check if it is simplified now
+	if ( is_string( $object ) ) {
+		return $object;
+	}
+
+	// return part of Object that makes most sense
+	switch ( $object['type'] ) {
+		case 'Link':
+			$object = $object['href'];
+			break;
+		default:
+			$object = $object['id'];
+			break;
+	}
+
+	return $object;
+}

includes/handler/class-create.php

@@ -0,0 +1,66 @@
+<?php
+namespace Activitypub\Handler;
+
+use WP_Error;
+use Activitypub\Collection\Interactions;
+
+use function Activitypub\is_activity_public;
+use function Activitypub\object_id_to_comment;
+
+/**
+ * Handle Create requests
+ */
+class Create {
+	/**
+	 * Initialize the class, registering WordPress hooks
+	 */
+	public static function init() {
+		\add_action(
+			'activitypub_inbox_create',
+			array( self::class, 'handle_create' ),
+			10,
+			3
+		);
+	}
+
+	/**
+	 * Handles "Create" requests
+	 *
+	 * @param array                $array   The activity-object
+	 * @param int                  $user_id The id of the local blog-user
+	 * @param Activitypub\Activity $object  The activity object
+	 *
+	 * @return void
+	 */
+	public static function handle_create( $array, $user_id, $object = null ) {
+		if (
+			! isset( $array['object'] ) ||
+			! isset( $array['object']['id'] )
+		) {
+			return;
+		}
+
+		// check if Activity is public or not
+		if ( ! is_activity_public( $array ) ) {
+			// @todo maybe send email
+			return;
+		}
+
+		$check_dupe = object_id_to_comment( $array['object']['id'] );
+
+		// if comment exists, call update action
+		if ( $check_dupe ) {
+			\do_action( 'activitypub_inbox_update', $array, $user_id, $object );
+			return;
+		}
+
+		$state    = Interactions::add_comment( $array );
+		$reaction = null;
+
+		if ( $state && ! \is_wp_error( $reaction ) ) {
+			$reaction = \get_comment( $state );
+		}
+
+		\do_action( 'activitypub_handled_create', $array, $user_id, $state, $reaction );
+	}
+}

includes/handler/class-delete.php

@@ -0,0 +1,178 @@
+<?php
+namespace Activitypub\Handler;
+
+use WP_Error;
+use WP_REST_Request;
+use Activitypub\Http;
+use Activitypub\Collection\Followers;
+use Activitypub\Collection\Interactions;
+
+/**
+ * Handles Delete requests.
+ */
+class Delete {
+	/**
+	 * Initialize the class, registering WordPress hooks
+	 */
+	public static function init() {
+		\add_action(
+			'activitypub_inbox_delete',
+			array( self::class, 'handle_delete' )
+		);
+
+		// defer signature verification for `Delete` requests.
+		\add_filter(
+			'activitypub_defer_signature_verification',
+			array( self::class, 'defer_signature_verification' ),
+			10,
+			2
+		);
+
+		// side effect
+		\add_action(
+			'activitypub_delete_actor_interactions',
+			array( self::class, 'delete_interactions' )
+		);
+	}
+
+	/**
+	 * Handles "Delete" requests.
+	 *
+	 * @param array $activity The delete activity.
+	 * @param int   $user_id  The ID of the user performing the delete activity.
+	 */
+	public static function handle_delete( $activity ) {
+		$object_type = isset( $activity['object']['type'] ) ? $activity['object']['type'] : '';
+
+		switch ( $object_type ) {
+			// Actor Types
+			// @see https://www.w3.org/TR/activitystreams-vocabulary/#actor-types
+			case 'Person':
+			case 'Group':
+			case 'Organization':
+			case 'Service':
+			case 'Application':
+				self::maybe_delete_follower( $activity );
+				break;
+			// Object and Link Types
+			// @see https://www.w3.org/TR/activitystreams-vocabulary/#object-types
+			case 'Note':
+			case 'Article':
+			case 'Image':
+			case 'Audio':
+			case 'Video':
+			case 'Event':
+			case 'Document':
+				self::maybe_delete_interaction( $activity );
+				break;
+			// Tombstone Type
+			// @see: https://www.w3.org/TR/activitystreams-vocabulary/#dfn-tombstone
+			case 'Tombstone':
+				self::maybe_delete_interaction( $activity );
+				break;
+			// Minimal Activity
+			// @see https://www.w3.org/TR/activitystreams-core/#example-1
+			default:
+				// ignore non Minimal Activities.
+				if ( ! is_string( $activity['object'] ) ) {
+					return;
+				}
+
+				// check if Object is an Actor.
+				if ( $activity['actor'] === $activity['object'] ) {
+					self::maybe_delete_follower( $activity );
+					self::maybe_delete_interactions( $activity );
+				} else { // assume a interaction otherwise.
+					self::maybe_delete_interaction( $activity );
+				}
+				// maybe handle Delete Activity for other Object Types.
+				break;
+		}
+	}
+
+	/**
+	 * Delete a Follower if Actor-URL is a Tombstone.
+	 *
+	 * @param array $activity The delete activity.
+	 */
+	public static function maybe_delete_follower( $activity ) {
+		$follower = Followers::get_follower_by_actor( $activity['actor'] );
+
+		// verify if Actor is deleted.
+		if ( $follower && Http::is_tombstone( $activity['actor'] ) ) {
+			$follower->delete();
+		}
+	}
+
+	/**
+	 * Delete Reactions if Actor-URL is a Tombstone.
+	 *
+	 * @param array $activity The delete activity.
+	 */
+	public static function maybe_delete_interactions( $activity ) {
+		// verify if Actor is deleted.
+		if ( Http::is_tombstone( $activity['actor'] ) ) {
+			\wp_schedule_single_event(
+				\time(),
+				'activitypub_delete_actor_interactions',
+				array( $activity['actor'] )
+			);
+		}
+	}
+
+	/**
+	 * Delete comments from an Actor.
+	 *
+	 * @param array $comments The comments to delete.
+	 */
+	public static function delete_interactions( $actor ) {
+		$comments = Interactions::get_interactions_by_actor( $actor );
+
+		if ( is_array( $comments ) ) {
+			foreach ( $comments as $comment ) {
+				wp_delete_comment( $comment->comment_ID );
+			}
+		}
+	}
+
+	/**
+	 * Delete a Reaction if URL is a Tombstone.
+	 *
+	 * @param array $activity The delete activity.
+	 *
+	 * @return void
+	 */
+	public static function maybe_delete_interaction( $activity ) {
+		if ( is_array( $activity['object'] ) ) {
+			$id = $activity['object']['id'];
+		} else {
+			$id = $activity['object'];
+		}
+
+		$comments = Interactions::get_interaction_by_id( $id );
+
+		if ( $comments && Http::is_tombstone( $id ) ) {
+			foreach ( $comments as $comment ) {
+				wp_delete_comment( $comment->comment_ID, true );
+			}
+		}
+	}
+
+	/**
+	 * Defer signature verification for `Delete` requests.
+	 *
+	 * @param bool            $defer   Whether to defer signature verification.
+	 * @param WP_REST_Request $request The request object.
+	 *
+	 * @return bool Whether to defer signature verification.
+	 */
+	public static function defer_signature_verification( $defer, $request ) {
+		$json = $request->get_json_params();
+
+		if ( isset( $json['type'] ) && 'Delete' === $json['type'] ) {
+			return true;
+		}
+
+		return false;
+	}
+}

includes/handler/class-follow.php

@@ -0,0 +1,92 @@
+<?php
+namespace Activitypub\Handler;
+
+use Activitypub\Http;
+use Activitypub\Activity\Activity;
+use Activitypub\Collection\Users;
+use Activitypub\Collection\Followers;
+use Activitypub\Model\Follow_Request;
+
+/**
+ * Handle Follow requests
+ */
+class Follow {
+	/**
+	 * Initialize the class, registering WordPress hooks
+	 */
+	public static function init() {
+		\add_action(
+			'activitypub_inbox_follow',
+			array( self::class, 'handle_follow' )
+		);
+
+		\add_action(
+			'activitypub_send_follow_response',
+			array( self::class, 'send_follow_response' ),
+			10,
+			4
+		);
+	}
+
+	/**
+	 * Handle "Follow" requests
+	 *
+	 * @param array $activity The activity object
+	 * @param int   $user_id  The user ID
+	 */
+	public static function handle_follow( $activity ) {
+		$user = Users::get_by_resource( $activity['object'] );
+
+		if ( ! $user || is_wp_error( $user ) ) {
+			// If we can not find a user,
+			// we can not initiate a follow process
+			return;
+		}
+
+		$user_id = $user->get__id();
+
+		// save follower
+		$follower = Followers::add_follower(
+			$user_id,
+			$activity['actor']
+		);
+
+		if ( \is_wp_error( $follower ) ) {
+			// it is not even possible to send a "Reject" or "Accept" because
+			// we can not get the Remote-Inbox
+			return;
+		}
+		
+		// save follow request by this follower
+		$follow_request = Follow_Request::save( $follower, $user_id, $activity['id'] );
+
+		if ( ! $user->get_manually_approves_followers() ) {
+			$follow_request->accept();
+		}
+	
+	}
+
+	/**
+	 * Send Follow response
+	 *
+	 * @param Activitypub\Model\User     $user     The Target Users ActivityPub object
+	 * @param Activitypub\Model\Follower $follower The Followers ActivityPub object
+	 * @param array|object               $object   The ActivityPub follow object
+	 * @param string                     $type     The reponse object type: 'Accept' or 'Reject'
+	 *
+	 * @return void
+	 */
+	public static function send_follow_response( $user, $follower, $object, $type ) {
+		// send activity
+		$activity = new Activity();
+		$activity->set_type( $type );
+		$activity->set_object( $object );
+		$activity->set_actor( $user->get_id() );
+		$activity->set_to( $follower->get_id() );
+		$activity->set_id( $user->get_id() . '#accept-' . \preg_replace( '~^https?://~', '', $follower->get_id() ) . '-' . \time() );
+
+		$activity = $activity->to_json();
+
+		Http::post( $follower->get_shared_inbox(), $activity, $user->get__id() );
+	}
+}

includes/handler/class-undo.php

@@ -0,0 +1,46 @@
+<?php
+namespace Activitypub\Handler;
+
+use Activitypub\Collection\Users;
+use Activitypub\Model\Follow_Request;
+
+/**
+ * Handle Undo requests
+ */
+class Undo {
+	/**
+	 * Initialize the class, registering WordPress hooks
+	 */
+	public static function init() {
+		\add_action(
+			'activitypub_inbox_undo',
+			array( self::class, 'handle_undo' )
+		);
+	}
+
+	/**
+	 * Handle "Unfollow" requests
+	 *
+	 * @param array $activity The JSON "Undo" Activity
+	 * @param int   $user_id  The ID of the ID of the WordPress User
+	 */
+	public static function handle_undo( $activity ) {
+		if (
+			isset( $activity['object']['type'] ) &&
+			'Follow' === $activity['object']['type'] &&
+			isset( $activity['object']['object'] ) &&
+			filter_var( $activity['object']['object'], FILTER_VALIDATE_URL )
+		) {
+			$user = Users::get_by_resource( $activity['object']['object'] );
+
+			if ( ! $user || is_wp_error( $user ) ) {
+				// If we can not find a user,
+				// we can not initiate a follow process
+				return;
+			}
+
+			$follow_request = Follow_Request::get_from_array( $activity['object'] );
+			$follow_request->delete();
+		}
+	}
+}

includes/handler/class-update.php

@@ -0,0 +1,92 @@
+<?php
+namespace Activitypub\Handler;
+
+use WP_Error;
+use Activitypub\Collection\Interactions;
+
+use function Activitypub\get_remote_metadata_by_actor;
+
+/**
+ * Handle Update requests.
+ */
+class Update {
+	/**
+	 * Initialize the class, registering WordPress hooks
+	 */
+	public static function init() {
+		\add_action(
+			'activitypub_inbox_update',
+			array( self::class, 'handle_update' )
+		);
+	}
+
+	/**
+	 * Handle "Update" requests
+	 *
+	 * @param array                $array   The activity-object
+	 * @param int                  $user_id The id of the local blog-user
+	 */
+	public static function handle_update( $array ) {
+		$object_type = isset( $array['object']['type'] ) ? $array['object']['type'] : '';
+
+		switch ( $object_type ) {
+			// Actor Types
+			// @see https://www.w3.org/TR/activitystreams-vocabulary/#actor-types
+			case 'Person':
+			case 'Group':
+			case 'Organization':
+			case 'Service':
+			case 'Application':
+				self::update_actor( $array );
+				break;
+			// Object and Link Types
+			// @see https://www.w3.org/TR/activitystreams-vocabulary/#object-types
+			case 'Note':
+			case 'Article':
+			case 'Image':
+			case 'Audio':
+			case 'Video':
+			case 'Event':
+			case 'Document':
+				self::update_interaction( $array );
+				break;
+			// Minimal Activity
+			// @see https://www.w3.org/TR/activitystreams-core/#example-1
+			default:
+				break;
+		}
+	}
+
+	/**
+	 * Update an Interaction
+	 *
+	 * @param array $activity The activity-object
+	 * @param int   $user_id  The id of the local blog-user
+	 *
+	 * @return void
+	 */
+	public static function update_interaction( $activity ) {
+		$state    = Interactions::update_comment( $activity );
+		$reaction = null;
+
+		if ( $state && ! \is_wp_error( $reaction ) ) {
+			$reaction = \get_comment( $state );
+		}
+
+		\do_action( 'activitypub_handled_update', $activity, null, $state, $reaction );
+	}
+
+	/**
+	 * Update an Actor
+	 *
+	 * @param array $activity The activity-object
+	 *
+	 * @return void
+	 */
+	public static function update_actor( $activity ) {
+		// update cache
+		get_remote_metadata_by_actor( $activity['actor'], false );
+
+		// @todo maybe also update all interactions
+	}
+}

includes/help.php

@@ -12,7 +12,7 @@
 				'<dt><code>[ap_content apply_filters="yes"]</code></dt>' .
 				'<dd>' . \wp_kses( __( 'The post\'s content. With <code>apply_filters</code> you can decide if filters (<code>apply_filters( \'the_content\', $content )</code>) should be applied or not (default is <code>yes</code>). The values can be <code>yes</code> or <code>no</code>. <code>apply_filters</code> attribute is optional.', 'activitypub' ), array( 'code' => array() ) ) . '</dd>' .
 				'<dt><code>[ap_excerpt length="400"]</code></dt>' .
-				'<dd>' . \wp_kses( __( 'The post\'s excerpt (default 400 chars). <code>length</code> attribute is optional.', 'activitypub' ), array( 'code' => array() ) ) . '</dd>' .
+				'<dd>' . \wp_kses( __( 'The post\'s excerpt (uses <code>the_excerpt</code> if that is set). If no excerpt is provided, will truncate at <code>length</code> (optional, default = 400).', 'activitypub' ), array( 'code' => array() ) ) . '</dd>' .
 				'<dt><code>[ap_permalink type="url"]</code></dt>' .
 				'<dd>' . \wp_kses( __( 'The post\'s permalink. <code>type</code> can be either: <code>url</code> or <code>html</code> (an &lt;a /&gt; tag). <code>type</code> attribute is optional.', 'activitypub' ), array( 'code' => array() ) ) . '</dd>' .
 				'<dt><code>[ap_shortlink type="url"]</code></dt>' .

includes/model/class-application-user.php

@@ -29,6 +29,13 @@ class Application_User extends Blog_User {
 	 */
 	protected $discoverable = false;
 
+	/**
+	 * The instance actor by default must manually approve all followers.
+	 * 
+	 * @var boolean
+	 */
+	protected $manually_approves_followers = true;
+
 	/**
 	 * Get the User-Url.
 	 *
@@ -38,12 +45,21 @@ class Application_User extends Blog_User {
 		return get_rest_url_by_path( 'application' );
 	}
 
+	/**
+	 * Returns the User-URL with @-Prefix for the username.
+	 *
+	 * @return string The User-URL with @-Prefix for the username.
+	 */
+	public function get_alternate_url() {
+		return \esc_url( \trailingslashit( get_home_url() ) . '@' . $this->get_preferred_username() );
+	}
+
 	public function get_name() {
 		return 'application';
 	}
 
 	public function get_preferred_username() {
-		return $this::get_name();
+		return $this->get_name();
 	}
 
 	public function get_followers() {
@@ -69,4 +85,8 @@ class Application_User extends Blog_User {
 	public function get_indexable() {
 		return false;
 	}
+
+	public function get_type() {
+		return $this->type;
+	}
 }

includes/model/class-blog-user.php

@@ -100,12 +100,12 @@ class Blog_User extends User {
 	}
 
 	/**
-	 * Returns the User-URL with @-Prefix for the username.
+	 * Get blog's homepage URL.
 	 *
-	 * @return string The User-URL with @-Prefix for the username.
+	 * @return string The User-Url.
 	 */
-	public function get_at_url() {
+	public function get_alternate_url() {
-		return \esc_url( \trailingslashit( get_home_url() ) . '@' . $this->get_preferred_username() );
+		return \esc_url( \trailingslashit( get_home_url() ) );
 	}
 
 	/**

includes/model/class-follow-request.php

@@ -0,0 +1,215 @@
+<?php
+namespace Activitypub\Model;
+
+use WP_Error;
+
+use Activitypub\Activity\Activity;
+use Activitypub\Activity\Base_Object;
+use Activitypub\Collection\Users;
+use Activitypub\Model\Follower;
+use Activitypub\Http;
+
+/**
+ * ActivityPub Follow Class
+ *
+ * This Object represents a Follow object.
+ * There is no direct reference to a WordPress User here.
+ *
+ * @author André Menrath
+ *
+ * @see https://www.w3.org/TR/activitypub/#follow-activity-inbox
+ */
+class Follow_Request extends Base_Object {
+	const FOLLOW_REQUEST_POST_TYPE = 'ap_follow_request';
+
+	/**
+	 * Stores theinternal  WordPress post id of the post of type ap_follow_request
+	 * 
+	 * @var string
+	 */
+	protected $_id;
+
+	/**
+	 * The id/URI of the follower
+	 * @var string
+	 */
+	protected $actor;
+
+	/**
+	 * The internal WordPress post id of the follower
+	 * @var string
+	 */
+	protected $_actor;
+
+	/**
+	 * @param int $id
+	 * @return Follow_Request $follow_request
+	 */
+	public static function get_from_array( $array ) {
+		$follow_request = self::init_from_array( $array );
+		if ( ! self::is_valid( $follow_request ) ) {
+			return;
+		}
+		if ( ! $follow_request->get__id() ) {
+			$follow_request->set__id( self::get_follow_request_id_by_uri( $follow_request->get_id() ) );
+		}
+		return $follow_request;
+	}
+
+	/**
+	 * Retrieve the WordPress post id of the follow request by its id (URI)
+	 */
+	public static function get_follow_request_id_by_uri( $uri ) {
+		global $wpdb;
+    	return $wpdb->get_var( $wpdb->prepare( "SELECT ID FROM $wpdb->posts WHERE guid=%s", esc_sql( $uri ) ) );
+	}
+
+
+	/**
+	 * Check if the follow request is valid which means it fits to the already stored data.
+	 * 
+	 * @param Follow_Request $follow_request The follow request to be checked.
+	 * @return bool Whether the follow request is valid.
+	 */
+	public static function is_valid( $follow_request ) {
+		if ( self::class != get_class( $follow_request ) ) {
+			return false;
+		}
+		if ( 'Follow' != $follow_request->get_type() ) {
+			return false;
+		}
+
+    	$id = self::get_follow_request_id_by_uri( $follow_request->get_id() );
+		if ( ! $id || is_wp_error( $id ) ) {
+			return false;
+		}
+		if ( self::FOLLOW_REQUEST_POST_TYPE != get_post_type( $id) ) {
+			return false;
+		}
+
+		$post = get_post( $id );
+		$follower = get_post_parent( $id );
+		if ( $follower->guid != $follow_request->get_actor() ) {
+			return false;
+		}
+		return true;
+	}
+
+	/**
+	 * @param int $id
+	 * @return Follow_Request $follow_request
+	 */
+	public static function from_wp_id( $id ) {
+		if ( self::FOLLOW_REQUEST_POST_TYPE != get_post_type( $id ) ){
+			return;
+		}
+		$post = get_post( $id );
+
+		$follow_request = new static;
+		$follow_request->set_id( $post->guid );
+		$follow_request->set__id( $post->ID );
+		$follow_request->set_type( 'Follow' );
+
+		return $follow_request;
+	}
+
+	/**
+	 * Save the current Follower-Object.
+	 *
+	 * @param Follower $follower
+	 *
+	 * @return Follow_Request|WP_Error The Follow_Request or an WP_Error.
+	 */
+	public static function save( $follower, $user_id, $activity_id ) {
+		$follower_id = $follower->get__id();
+		$meta_input = array(
+			'activitypub_user_id' => $user_id,
+		);
+
+		$args = array(
+			'guid'         => $activity_id,
+			'post_author'  => 0,
+			'post_type'    => self::FOLLOW_REQUEST_POST_TYPE,
+			'post_status'  => 'pending',
+			'post_parent'  => $follower_id,
+			'meta_input'   => $meta_input,
+			'mime_type'    => 'text/plain'
+		);
+
+		$post_id = wp_insert_post( $args );
+
+
+		return self::from_wp_id( $post_id );
+	}
+
+	/**
+	 * Check if the user is allowed to handle this follow request.
+	 * 
+	 * Usually needed for the ajax functions.
+	 * @return bool Whether the user is allowed.
+	 */
+	public function can_handle_follow_request() {
+		$target_actor = get_post_meta( $this->get__id(), 'activitypub_user_id');
+		if ( get_current_user_id() == $target_actor || current_user_can( 'manage_options' )) {
+			return true;
+		}
+	}
+
+	/**
+	 * Reject the follow request
+	 */
+	public function reject() {
+		wp_update_post( 
+			array(
+				'ID' => $this->get__id(),
+				'post_status' => 'rejected',
+			)
+		);
+		$this->send_response( 'Reject' );
+		$this->delete();
+	}
+
+	/**
+	 * Approve the follow request
+	 */
+	public function approve() {
+		wp_update_post( 
+			array(
+				'ID' => $this->get__id(),
+				'post_status' => 'approved',
+			)
+		);
+		$this->send_response( 'Accept' );
+	}
+
+	/**
+	 * Delete the follow request
+	 * 
+	 * This should only be called after it has been rejected.
+	 */
+	public function delete() {
+		wp_delete_post( $this->get__id() );
+	}
+
+	/**
+	 * Prepere the sending of the follow request response and hand it over to the sending handler.
+	 */
+	public function send_response( $type ) {
+		$user_id = get_post_meta( $this->get__id(), 'activitypub_user_id')[0];
+		$user = Users::get_by_id( $user_id );
+
+		$follower_id = wp_get_post_parent_id( $this->get__id() );
+		$follower = Follower::init_from_cpt( get_post( $follower_id ) );
+		
+		$actor = $follower->get_id();
+
+		$object = array(
+			'id'    => $this->get_id(),
+			'type'  => $this->get_type(),
+			'actor' => $actor,
+			'object' => $user,
+		);
+
+		do_action( 'activitypub_send_follow_response', $user, $follower, $object, $type);
+	}
+}

includes/model/class-follower.php

@@ -19,7 +19,7 @@ use Activitypub\Collection\Followers;
  */
 class Follower extends Actor {
 	/**
-	 * The complete Remote-Profile of the Follower
+	 * The complete Remote-Profile of the Follower.
 	 *
 	 * @var array
 	 */
@@ -34,6 +34,13 @@ class Follower extends Actor {
 		return get_post_meta( $this->_id, 'activitypub_errors' );
 	}
 
+	/**
+	 * Getter function for the internal WordPress id.
+	 */
+	public function get__id() {
+		return $this->_id;
+	}
+																																											
 	/**
 	 * Get the Summary.
 	 *
@@ -304,9 +311,9 @@ class Follower extends Actor {
 	/**
 	 * Convert a Custom-Post-Type input to an Activitypub\Model\Follower.
 	 *
-	 * @return string The JSON string.
+	 * @param WP_Post The JSON string.
 	 *
-	 * @return array Activitypub\Model\Follower
+	 * @return \Activitypub\Model\Follower $object
 	 */
 	public static function init_from_cpt( $post ) {
 		$actor_json = get_post_meta( $post->ID, 'activitypub_actor_json', true );

includes/model/class-post.php

@@ -1,132 +0,0 @@
-<?php
-namespace Activitypub\Model;
-
-use Activitypub\Transformer\Post as Transformer_Post;
-
-/**
- * ActivityPub Post Class
- *
- * @author Matthias Pfefferle
- */
-class Post {
-	/**
-	 * The \Activitypub\Activity\Base_Object object.
-	 *
-	 * @var \Activitypub\Activity\Base_Object
-	 */
-	protected $object;
-
-	/**
-	 * The WordPress Post Object.
-	 *
-	 * @var WP_Post
-	 */
-	private $post;
-
-	/**
-	 * Constructor
-	 *
-	 * @param WP_Post $post
-	 * @param int     $post_author
-	 */
-	// phpcs:ignore Generic.CodeAnalysis.UnusedFunctionParameter.FoundAfterLastUsed, VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable
-	public function __construct( $post, $post_author = null ) {
-		_deprecated_function( __CLASS__, '1.0.0', '\Activitypub\Transformer\Post' );
-
-		$this->post = $post;
-		$transformer = new Transformer_Post();
-		$this->object = $transformer->set_wp_post( $post )->to_object();
-	}
-
-	/**
-	 * Returns the User ID.
-	 *
-	 * @return int the User ID.
-	 */
-	public function get_user_id() {
-		return apply_filters( 'activitypub_post_user_id', $this->post->post_author, $this->post );
-	}
-
-	/**
-	 * Converts this Object into an Array.
-	 *
-	 * @return array the array representation of a Post.
-	 */
-	public function to_array() {
-		return \apply_filters( 'activitypub_post', $this->object->to_array(), $this->post );
-	}
-
-	/**
-	 * Returns the Actor of this Object.
-	 *
-	 * @return string The URL of the Actor.
-	 */
-	public function get_actor() {
-		$user = User_Factory::get_by_id( $this->get_user_id() );
-
-		return $user->get_url();
-	}
-
-	/**
-	 * Converts this Object into a JSON String
-	 *
-	 * @return string
-	 */
-	public function to_json() {
-		return \wp_json_encode( $this->to_array(), \JSON_HEX_TAG | \JSON_HEX_AMP | \JSON_HEX_QUOT );
-	}
-
-	/**
-	 * Returns the URL of an Activity Object
-	 *
-	 * @return string
-	 */
-	public function get_url() {
-		return $this->object->get_url();
-	}
-
-	/**
-	 * Returns the ID of an Activity Object
-	 *
-	 * @return string
-	 */
-	public function get_id() {
-		return $this->object->get_id();
-	}
-
-	/**
-	 * Returns a list of Image Attachments
-	 *
-	 * @return array
-	 */
-	public function get_attachments() {
-		return $this->object->get_attachment();
-	}
-
-	/**
-	 * Returns a list of Tags, used in the Post
-	 *
-	 * @return array
-	 */
-	public function get_tags() {
-		return $this->object->get_tag();
-	}
-
-	/**
-	 * Returns the as2 object-type for a given post
-	 *
-	 * @return string the object-type
-	 */
-	public function get_object_type() {
-		return $this->object->get_type();
-	}
-
-	/**
-	 * Returns the content for the ActivityPub Item.
-	 *
-	 * @return string the content
-	 */
-	public function get_content() {
-		return $this->object->get_content();
-	}
-}

includes/model/class-user.php

@@ -135,8 +135,8 @@ class User extends Actor {
 	 *
 	 * @return string The User-URL with @-Prefix for the username.
 	 */
-	public function get_at_url() {
+	public function get_alternate_url() {
-		return \esc_url( \trailingslashit( get_home_url() ) . '@' . $this->get_username() );
+		return \esc_url( \trailingslashit( get_home_url() ) . '@' . $this->get_preferred_username() );
 	}
 
 	public function get_preferred_username() {
@@ -226,6 +226,18 @@ class User extends Actor {
 		return get_rest_url_by_path( sprintf( 'users/%d/collections/featured', $this->get__id() ) );
 	}
 
+	public function get_endpoints() {
+		$endpoints = null;
+
+		if ( ACTIVITYPUB_SHARED_INBOX_FEATURE ) {
+			$endpoints = array(
+				'sharedInbox' => get_rest_url_by_path( 'inbox' ),
+			);
+		}
+
+		return $endpoints;
+	}
+
 	/**
 	 * Extend the User-Output with Attachments.
 	 *

includes/peer/class-followers.php

@@ -1,34 +0,0 @@
-<?php
-namespace Activitypub\Peer;
-
-/**
- * ActivityPub Followers DB-Class
- *
- * @author Matthias Pfefferle
- */
-class Followers {
-
-	public static function get_followers( $author_id ) {
-		_deprecated_function( __METHOD__, '1.0.0', '\Activitypub\Collection\Followers::get_followers' );
-
-		return \Activitypub\Collection\Followers::get_followers( $author_id );
-	}
-
-	public static function count_followers( $author_id ) {
-		_deprecated_function( __METHOD__, '1.0.0', '\Activitypub\Collection\Followers::count_followers' );
-
-		return \Activitypub\Collection\Followers::count_followers( $author_id );
-	}
-
-	public static function add_follower( $actor, $author_id ) {
-		_deprecated_function( __METHOD__, '1.0.0', '\Activitypub\Collection\Followers::add_follower' );
-
-		return \Activitypub\Collection\Followers::add_follower( $author_id, $actor );
-	}
-
-	public static function remove_follower( $actor, $author_id ) {
-		_deprecated_function( __METHOD__, '1.0.0', '\Activitypub\Collection\Followers::remove_follower' );
-
-		return \Activitypub\Collection\Followers::remove_follower( $author_id, $actor );
-	}
-}

includes/rest/class-collection.php

@@ -4,7 +4,7 @@ namespace Activitypub\Rest;
 use WP_Error;
 use WP_REST_Server;
 use WP_REST_Response;
-use Activitypub\Transformer\Transformers_Manager;
+use Activitypub\Transformer\Post;
 use Activitypub\Activity\Activity;
 use Activitypub\Collection\Users as User_Collection;
 
@@ -168,7 +168,7 @@ class Collection {
 		);
 
 		foreach ( $posts as $post ) {
-			$response['orderedItems'][] = Transformers_Manager::instance()->get_transformer( $post )->to_object()->to_array();
+			$response['orderedItems'][] = Post::transform( $post )->to_object()->to_array();
 		}
 
 		$rest_response = new WP_REST_Response( $response, 200 );

includes/rest/class-followers.php

@@ -94,7 +94,7 @@ class Followers {
 
 		// phpcs:ignore
 		$json->orderedItems = array_map(
-			function( $item ) use ( $context ) {
+			function ( $item ) use ( $context ) {
 				if ( 'full' === $context ) {
 					return $item->to_array();
 				}

includes/rest/class-inbox.php

@@ -8,9 +8,11 @@ use Activitypub\Activity\Activity;
 use Activitypub\Collection\Users as User_Collection;
 
 use function Activitypub\get_context;
+use function Activitypub\object_to_uri;
 use function Activitypub\url_to_authorid;
 use function Activitypub\get_rest_url_by_path;
 use function Activitypub\get_remote_metadata_by_actor;
+use function Activitypub\extract_recipients_from_activity;
 
 /**
  * ActivityPub Inbox REST-Class
@@ -25,8 +27,6 @@ class Inbox {
 	 */
 	public static function init() {
 		self::register_routes();
-
-		\add_action( 'activitypub_inbox_create', array( self::class, 'handle_create' ), 10, 2 );
 	}
 
 	/**
@@ -94,11 +94,8 @@ class Inbox {
 		$json->generator = 'http://wordpress.org/?v=' . \get_bloginfo_rss( 'version' );
 		$json->type = 'OrderedCollectionPage';
 		$json->partOf = get_rest_url_by_path( sprintf( 'users/%d/inbox', $user->get__id() ) ); // phpcs:ignore
-
 		$json->totalItems = 0; // phpcs:ignore
-
 		$json->orderedItems = array(); // phpcs:ignore
-
 		$json->first = $json->partOf; // phpcs:ignore
 
 		// filter output
@@ -131,11 +128,12 @@ class Inbox {
 		}
 
 		$data     = $request->get_json_params();
+		$activity = Activity::init_from_array( $data );
 		$type     = $request->get_param( 'type' );
 		$type     = \strtolower( $type );
 
-		\do_action( 'activitypub_inbox', $data, $user->get__id(), $type );
+		\do_action( 'activitypub_inbox', $data, $user->get__id(), $type, $activity );
-		\do_action( "activitypub_inbox_{$type}", $data, $user->get__id() );
+		\do_action( "activitypub_inbox_{$type}", $data, $user->get__id(), $activity );
 
 		$rest_response = new WP_REST_Response( array(), 202 );
 		$rest_response->header( 'Content-Type', 'application/activity+json; charset=' . get_option( 'blog_charset' ) );
@@ -152,38 +150,12 @@ class Inbox {
 	 */
 	public static function shared_inbox_post( $request ) {
 		$data     = $request->get_json_params();
+		$activity = Activity::init_from_array( $data );
 		$type     = $request->get_param( 'type' );
-		$users = self::extract_recipients( $data );
-
-		if ( ! $users ) {
-			return new WP_Error(
-				'rest_invalid_param',
-				\__( 'No recipients found', 'activitypub' ),
-				array(
-					'status' => 400,
-					'params' => array(
-						'to' => \__( 'Please check/validate "to" field', 'activitypub' ),
-						'bto' => \__( 'Please check/validate "bto" field', 'activitypub' ),
-						'cc' => \__( 'Please check/validate "cc" field', 'activitypub' ),
-						'bcc' => \__( 'Please check/validate "bcc" field', 'activitypub' ),
-						'audience' => \__( 'Please check/validate "audience" field', 'activitypub' ),
-					),
-				)
-			);
-		}
-
-		foreach ( $users as $user ) {
-			$user = User_Collection::get_by_various( $user );
-
-			if ( is_wp_error( $user ) ) {
-				continue;
-			}
-
 		$type     = \strtolower( $type );
 
-			\do_action( 'activitypub_inbox', $data, $user->ID, $type );
+		\do_action( 'activitypub_inbox', $data, null, $type, $activity );
-			\do_action( "activitypub_inbox_{$type}", $data, $user->ID );
+		\do_action( "activitypub_inbox_{$type}", $data, null, $activity );
-		}
 
 		$rest_response = new WP_REST_Response( array(), 202 );
 		$rest_response->header( 'Content-Type', 'application/activity+json; charset=' . get_option( 'blog_charset' ) );
@@ -235,15 +207,8 @@ class Inbox {
 
 		$params['actor'] = array(
 			'required' => true,
-			'sanitize_callback' => function( $param, $request, $key ) {
+			'sanitize_callback' => function ( $param, $request, $key ) {
-				if ( \is_array( $param ) ) {
+				return object_to_uri( $param );
-					if ( isset( $param['id'] ) ) {
-						$param = $param['id'];
-					} else {
-						$param = $param['url'];
-					}
-				}
-				return \esc_url_raw( $param );
 			},
 		);
 
@@ -251,7 +216,7 @@ class Inbox {
 			'required' => true,
 			//'type' => 'enum',
 			//'enum' => array( 'Create' ),
-			//'sanitize_callback' => function( $param, $request, $key ) {
+			//'sanitize_callback' => function ( $param, $request, $key ) {
 			//  return \strtolower( $param );
 			//},
 		);
@@ -284,11 +249,8 @@ class Inbox {
 		$params['actor'] = array(
 			'required' => true,
 			//'type' => array( 'object', 'string' ),
-			'sanitize_callback' => function( $param, $request, $key ) {
+			'sanitize_callback' => function ( $param, $request, $key ) {
-				if ( ! \is_string( $param ) ) {
+				return object_to_uri( $param );
-					$param = $param['id'];
-				}
-				return \esc_url_raw( $param );
 			},
 		);
 
@@ -296,7 +258,7 @@ class Inbox {
 			'required' => true,
 			//'type' => 'enum',
 			//'enum' => array( 'Create' ),
-			//'sanitize_callback' => function( $param, $request, $key ) {
+			//'sanitize_callback' => function ( $param, $request, $key ) {
 			//  return \strtolower( $param );
 			//},
 		);
@@ -308,7 +270,7 @@ class Inbox {
 
 		$params['to'] = array(
 			'required' => false,
-			'sanitize_callback' => function( $param, $request, $key ) {
+			'sanitize_callback' => function ( $param, $request, $key ) {
 				if ( \is_string( $param ) ) {
 					$param = array( $param );
 				}
@@ -318,7 +280,7 @@ class Inbox {
 		);
 
 		$params['cc'] = array(
-			'sanitize_callback' => function( $param, $request, $key ) {
+			'sanitize_callback' => function ( $param, $request, $key ) {
 				if ( \is_string( $param ) ) {
 					$param = array( $param );
 				}
@@ -328,7 +290,7 @@ class Inbox {
 		);
 
 		$params['bcc'] = array(
-			'sanitize_callback' => function( $param, $request, $key ) {
+			'sanitize_callback' => function ( $param, $request, $key ) {
 				if ( \is_string( $param ) ) {
 					$param = array( $param );
 				}
@@ -340,121 +302,6 @@ class Inbox {
 		return $params;
 	}
 
-	/**
-	 * Handles "Create" requests
-	 *
-	 * @param  array $object  The activity-object
-	 * @param  int   $user_id The id of the local blog-user
-	 */
-	public static function handle_create( $object, $user_id ) {
-		$meta = get_remote_metadata_by_actor( $object['actor'] );
-
-		if ( ! isset( $object['object']['inReplyTo'] ) ) {
-			return;
-		}
-
-		// check if Activity is public or not
-		if ( ! self::is_activity_public( $object ) ) {
-			// @todo maybe send email
-			return;
-		}
-
-		$comment_post_id = \url_to_postid( $object['object']['inReplyTo'] );
-
-		// save only replys and reactions
-		if ( ! $comment_post_id ) {
-			return false;
-		}
-
-		$commentdata = array(
-			'comment_post_ID' => $comment_post_id,
-			'comment_author' => \esc_attr( $meta['name'] ),
-			'comment_author_url' => \esc_url_raw( $object['actor'] ),
-			'comment_content' => addslashes( \wp_kses( $object['object']['content'], 'pre_comment_content' ) ),
-			'comment_type' => 'comment',
-			'comment_author_email' => '',
-			'comment_parent' => 0,
-			'comment_meta' => array(
-				'source_url' => \esc_url_raw( $object['object']['url'] ),
-				'avatar_url' => \esc_url_raw( $meta['icon']['url'] ),
-				'protocol' => 'activitypub',
-			),
-		);
-
-		// disable flood control
-		\remove_action( 'check_comment_flood', 'check_comment_flood_db', 10 );
-
-		// do not require email for AP entries
-		\add_filter( 'pre_option_require_name_email', '__return_false' );
-
-		// No nonce possible for this submission route
-		\add_filter(
-			'akismet_comment_nonce',
-			function() {
-				return 'inactive';
-			}
-		);
-
-		\add_filter( 'wp_kses_allowed_html', array( self::class, 'allowed_comment_html' ), 10, 2 );
-
-		$state = \wp_new_comment( $commentdata, true );
-
-		\remove_filter( 'wp_kses_allowed_html', array( self::class, 'allowed_comment_html' ) );
-		\remove_filter( 'pre_option_require_name_email', '__return_false' );
-
-		// re-add flood control
-		\add_action( 'check_comment_flood', 'check_comment_flood_db', 10, 4 );
-
-		do_action( 'activitypub_handled_create', $object, $user_id, $state, $commentdata );
-	}
-
-	/**
-	 * Extract recipient URLs from Activity object
-	 *
-	 * @param  array $data
-	 *
-	 * @return array The list of user URLs
-	 */
-	public static function extract_recipients( $data ) {
-		$recipient_items = array();
-
-		foreach ( array( 'to', 'bto', 'cc', 'bcc', 'audience' ) as $i ) {
-			if ( array_key_exists( $i, $data ) ) {
-				if ( is_array( $data[ $i ] ) ) {
-					$recipient = $data[ $i ];
-				} else {
-					$recipient = array( $data[ $i ] );
-				}
-				$recipient_items = array_merge( $recipient_items, $recipient );
-			}
-
-			if ( is_array( $data['object'] ) && array_key_exists( $i, $data['object'] ) ) {
-				if ( is_array( $data['object'][ $i ] ) ) {
-					$recipient = $data['object'][ $i ];
-				} else {
-					$recipient = array( $data['object'][ $i ] );
-				}
-				$recipient_items = array_merge( $recipient_items, $recipient );
-			}
-		}
-
-		$recipients = array();
-
-		// flatten array
-		foreach ( $recipient_items as $recipient ) {
-			if ( is_array( $recipient ) ) {
-				// check if recipient is an object
-				if ( array_key_exists( 'id', $recipient ) ) {
-					$recipients[] = $recipient['id'];
-				}
-			} else {
-				$recipients[] = $recipient;
-			}
-		}
-
-		return array_unique( $recipients );
-	}
-
 	/**
 	 * Get local user recipients
 	 *
@@ -463,7 +310,7 @@ class Inbox {
 	 * @return array The list of local users
 	 */
 	public static function get_recipients( $data ) {
-		$recipients = self::extract_recipients( $data );
+		$recipients = extract_recipients_from_activity( $data );
 		$users = array();
 
 		foreach ( $recipients as $recipient ) {
@@ -478,41 +325,4 @@ class Inbox {
 
 		return $users;
 	}
-
-	/**
-	 * Check if passed Activity is Public
-	 *
-	 * @param array $data
-	 * @return boolean
-	 */
-	public static function is_activity_public( $data ) {
-		$recipients = self::extract_recipients( $data );
-
-		return in_array( 'https://www.w3.org/ns/activitystreams#Public', $recipients, true );
-	}
-
-	/**
-	 * Adds line breaks to the list of allowed comment tags.
-	 *
-	 * @param  array  $allowedtags Allowed HTML tags.
-	 * @param  string $context     Context.
-	 * @return array               Filtered tag list.
-	 */
-	public static function allowed_comment_html( $allowedtags, $context = '' ) {
-		if ( 'pre_comment_content' !== $context ) {
-			// Do nothing.
-			return $allowedtags;
-		}
-
-		// Add `p` and `br` to the list of allowed tags.
-		if ( ! array_key_exists( 'br', $allowedtags ) ) {
-			$allowedtags['br'] = array();
-		}
-
-		if ( ! array_key_exists( 'p', $allowedtags ) ) {
-			$allowedtags['p'] = array();
-		}
-
-		return $allowedtags;
-	}
 }

includes/rest/class-nodeinfo.php

@@ -105,6 +105,12 @@ class Nodeinfo {
 			'outbound' => array(),
 		);
 
+		$nodeinfo['metadata'] = array(
+			'nodeName' => \get_bloginfo( 'name' ),
+			'nodeDescription' => \get_bloginfo( 'description' ),
+			'nodeIcon' => \get_site_icon_url(),
+		);
+
 		return new WP_REST_Response( $nodeinfo, 200 );
 	}
 
@@ -169,6 +175,10 @@ class Nodeinfo {
 				'rel' => 'http://nodeinfo.diaspora.software/ns/schema/2.0',
 				'href' => get_rest_url_by_path( 'nodeinfo' ),
 			),
+			array(
+				'rel' => 'https://www.w3.org/ns/activitystreams#Application',
+				'href' => get_rest_url_by_path( 'application' ),
+			),
 		);
 
 		return new \WP_REST_Response( $discovery, 200 );

includes/rest/class-outbox.php

@@ -5,7 +5,7 @@ use stdClass;
 use WP_Error;
 use WP_REST_Server;
 use WP_REST_Response;
-use Activitypub\Transformer\Transformers_Manager;
+use Activitypub\Transformer\Post;
 use Activitypub\Activity\Activity;
 use Activitypub\Collection\Users as User_Collection;
 
@@ -59,7 +59,7 @@ class Outbox {
 			return $user;
 		}
 
-		$post_types = array_keys( \get_option( 'activitypub_transformer_mapping', array( 'post' => 'activitypub/default', 'page' => 'activitypub/default' ) ) );
+		$post_types = \get_option( 'activitypub_support_post_types', array( 'post', 'page' ) );
 
 		$page = $request->get_param( 'page', 1 );
 
@@ -105,8 +105,7 @@ class Outbox {
 			);
 
 			foreach ( $posts as $post ) {
-				$transformer = \Activitypub\Transformer\Transformers_Manager::instance()->get_transformer( $post );
+				$post = Post::transform( $post )->to_object();
-				$post = $transformer->to_object();
 				$activity = new Activity();
 				$activity->set_type( 'Create' );
 				$activity->set_context( null );

includes/rest/class-server.php

@@ -110,14 +110,20 @@ class Server {
 		if ( 'GET' !== $request->get_method() ) {
 			$verified_request = Signature::verify_http_signature( $request );
 			if ( \is_wp_error( $verified_request ) ) {
-				return new WP_Error( 'activitypub_signature_verification', $verified_request->get_error_message(), array( 'status' => 401 ) );
+				return new WP_Error(
+					'activitypub_signature_verification',
+					$verified_request->get_error_message(),
+					array( 'status' => 401 )
+				);
 			}
-		} elseif ( 'GET' === $request->get_method() ) { // GET-Requests are only signed in secure mode
+		} elseif ( 'GET' === $request->get_method() && ACTIVITYPUB_AUTHORIZED_FETCH ) { // GET-Requests are only signed in secure mode
-			if ( ACTIVITYPUB_AUTHORIZED_FETCH ) {
 			$verified_request = Signature::verify_http_signature( $request );
 			if ( \is_wp_error( $verified_request ) ) {
-					return new WP_Error( 'activitypub_signature_verification', $verified_request->get_error_message(), array( 'status' => 401 ) );
+				return new WP_Error(
-				}
+					'activitypub_signature_verification',
+					$verified_request->get_error_message(),
+					array( 'status' => 401 )
+				);
 			}
 		}
 

includes/rest/class-users.php

@@ -50,14 +50,13 @@ class Users {
 				array(
 					'methods'             => WP_REST_Server::READABLE,
 					'callback'            => array( self::class, 'remote_follow_get' ),
-
+					'permission_callback' => '__return_true',
 					'args'                => array(
 						'resource' => array(
 							'required'          => true,
 							'sanitize_callback' => 'sanitize_text_field',
 						),
 					),
-					'permission_callback' => '__return_true',
 				),
 			)
 		);

includes/rest/class-webfinger.php

@@ -72,7 +72,7 @@ class Webfinger {
 		$params['resource'] = array(
 			'required' => true,
 			'type' => 'string',
-			'pattern' => '^acct:(.+)@(.+)$',
+			'pattern' => '^(acct:)|^(https?://)(.+)$',
 		);
 
 		return $params;
@@ -94,10 +94,13 @@ class Webfinger {
 
 		$aliases = array(
 			$user->get_url(),
+			$user->get_alternate_url(),
 		);
 
+		$aliases = array_unique( $aliases );
+
 		$profile = array(
-			'subject' => $resource,
+			'subject' => sprintf( 'acct:%s', $user->get_resource() ),
 			'aliases' => array_values( array_unique( $aliases ) ),
 			'links'   => array(
 				array(
@@ -113,6 +116,12 @@ class Webfinger {
 			),
 		);
 
+		if ( 'Person' !== $user->get_type() ) {
+			$profile['links'][0]['properties'] = array(
+				'https://www.w3.org/ns/activitystreams#type' => $user->get_type(),
+			);
+		}
+
 		return $profile;
 	}
 }

includes/table/class-follow-requests.php

@@ -0,0 +1,290 @@
+<?php
+namespace Activitypub\Table;
+
+use WP_List_Table;
+use Activitypub\Collection\Users;
+use Activitypub\Collection\Followers as FollowerCollection;
+use Activitypub\Collection\Follow_Requests as FollowerRequestCollection;
+use Activitypub\Model\Follow_Request;
+
+use function Activitypub\object_to_uri;
+
+if ( ! \class_exists( '\WP_List_Table' ) ) {
+		require_once ABSPATH . 'wp-admin/includes/class-wp-list-table.php';
+}
+
+/**
+ * Table that shows all follow requests for a user and allows handling those requests.
+ */
+class Follow_Requests extends WP_List_Table {
+	private $user_id;
+	public $follow_requests_count = 0;
+
+	public function __construct( $user_id = null ) {
+
+		if ( $user_id ) {
+			$this->user_id = $user_id;
+		} else {
+			$this->user_id = \get_current_user_id();
+		}
+
+		parent::__construct(
+			array(
+				'singular' => \__( 'Follower', 'activitypub' ),
+				'plural'   => \__( 'Followers', 'activitypub' ),
+				'ajax'     => true,
+			)
+		);
+	}
+
+	public function get_columns() {
+		return array(
+			'cb'         => '<input type="button">',
+			'action'     => \__( 'Action', 'activitypub' ),
+			'name'       => \__( 'Name', 'activitypub' ),
+			'url'        => \__( 'URL', 'activitypub' ),
+			'status'     => \__( 'Status', 'activitypub' ),
+			'published'  => \__( 'Created', 'activitypub' ),
+			'modified'   => \__( 'Last updated', 'activitypub' ),
+		);
+	}
+
+	public function get_sortable_columns() {
+		$sortable_columns = array(
+			'status' => array( 'status', false),
+			'name' => array( 'name', true ),
+			'modified'   => array( 'modified', false ),
+			'published'  => array( 'published', false ),
+		);
+
+		return $sortable_columns;
+	}
+
+	public function prepare_items() {
+		$columns = $this->get_columns();
+		$hidden  = array();
+
+		$this->process_action();
+		$this->_column_headers = array( $columns, $hidden, $this->get_sortable_columns() );
+
+		$page_num = $this->get_pagenum();
+		$per_page = 20;
+
+		$args = array();
+
+		// phpcs:ignore WordPress.Security.NonceVerification.Recommended
+		if ( isset( $_GET['orderby'] ) ) {
+			// phpcs:ignore WordPress.Security.NonceVerification.Recommended
+			$args['orderby'] = sanitize_text_field( wp_unslash( $_GET['orderby'] ) );
+		}
+
+		// phpcs:ignore WordPress.Security.NonceVerification.Recommended
+		if ( isset( $_GET['order'] ) ) {
+			// phpcs:ignore WordPress.Security.NonceVerification.Recommended
+			$args['order'] = sanitize_text_field( wp_unslash( $_GET['order'] ) );
+		}
+
+		// phpcs:ignore WordPress.Security.NonceVerification.Recommended
+		if ( isset( $_GET['s'] ) && isset( $_REQUEST['_wpnonce'] ) ) {
+			$nonce = sanitize_text_field( wp_unslash( $_REQUEST['_wpnonce'] ) );
+			if ( wp_verify_nonce( $nonce, 'bulk-' . $this->_args['plural'] ) ) {
+				// phpcs:ignore WordPress.Security.NonceVerification.Recommended
+				$args['s'] = sanitize_text_field( wp_unslash( $_GET['s'] ) );
+			}
+		}
+
+		$follow_requests_with_count = FollowerRequestCollection::get_follow_requests_for_user( $this->user_id, $per_page, $page_num, $args );
+
+		$follow_requests = $follow_requests_with_count['follow_requests'];
+		$counter         = $follow_requests_with_count['total_items'];
+		$this->follow_requests_count = $counter;
+
+		$this->items = array();
+		$this->set_pagination_args(
+			array(
+				'total_items' => $counter,
+				'total_pages' => ceil( $counter / $per_page ),
+				'per_page'    => $per_page,
+			)
+		);
+
+		foreach ( $follow_requests as $follow_request ) {
+			$item = array(
+				'status'     => esc_attr( $follow_request->status ),
+				'name'       => esc_attr( $follow_request->post_title ),
+				'url'        => esc_attr( $follow_request->follower_guid ),
+				'guid'       => esc_attr( $follow_request->guid ),
+				'id'         => esc_attr( $follow_request->id ),
+				'published'  => esc_attr( $follow_request->published ),
+				'modified'   => esc_attr( $follow_request->follower_modified ),
+			);
+
+			$this->items[] = $item;
+		}
+	}
+
+	public function get_bulk_actions() {
+		return array(
+			'reject'  => __( 'Reject', 'activitypub' ),
+			'approve' => __( 'Approve', 'activitypub' ),
+		);
+	}
+
+	public function column_default( $item, $column_name ) {
+		if ( ! array_key_exists( $column_name, $item ) ) {
+			return __( 'None', 'activitypub' );
+		}
+		return $item[ $column_name ];
+	}
+
+	public function column_status( $item ) {
+		$status = $item['status'];
+		switch ( $status ) {
+			case 'approved':
+				$color = 'success';
+				break;
+			case 'pending':
+				$color = 'warning';
+				break;
+			case 'rejected':
+				$color = 'danger';
+				break;
+			default:
+				$color = 'warning';
+		}
+		return sprintf(
+			'<span class="activitypub-settings-label activitypub-settings-label-%s">%s</span>',
+			$color,
+			ucfirst( $status )
+		);
+	}
+
+	public function column_avatar( $item ) {
+		return sprintf(
+			'<img src="%s" width="25px;" />',
+			$item['icon']
+		);
+	}
+
+	public function column_url( $item ) {
+		return sprintf(
+			'<a href="%s" target="_blank">%s</a>',
+			$item['url'],
+			$item['url']
+		);
+	}
+
+	public function column_cb( $item ) {
+		return sprintf( '<input type="checkbox" name="follow_requests[]" value="%s" />', esc_attr( $item['id'] ) );
+	}
+
+	public function ajax_response() {
+		$follow_action = $_REQUEST['follow_action'];
+		$id = $_REQUEST['follow_request'];
+		wp_verify_nonce( $_REQUEST['_wpnonce'], "activitypub_{$follow_action}_follow_request" );
+		$follow_request = Follow_Request::from_wp_id( $id );
+		if ( $follow_request->can_handle_follow_request() ) {
+			switch ( $follow_action ) {
+				case 'approve':
+					$follow_request->approve();
+					wp_die( 'approved' );
+				case 'reject':
+					$follow_request->reject();
+					wp_die( 'rejected' );
+				case 'delete':
+					$follow_request->delete();
+					wp_die( 'deleted' );
+			}
+		}
+		return;
+	}
+
+	private static function display_follow_request_action_button( $id, $follow_action, $display = true ) {
+		$url = add_query_arg(
+			array(
+				'follow_request' => $id,
+				'action'         => 'activitypub_handle_follow_request',
+				'follow_action'  => $follow_action,
+				'_wpnonce'       => wp_create_nonce( "activitypub_{$follow_action}_follow_request" ),
+			),
+			admin_url( 'admin-ajax.php' )
+		);
+		if ( $display ) {
+			$type = 'button';
+		} else {
+			$type = 'hidden';
+		}
+		printf(
+			'<input type="%s" class="button" value="%s" data-action="%s">',
+			esc_attr( $type ),
+			esc_attr__( ucfirst( $follow_action ), 'activitypub' ),
+			esc_url( $url )
+		);
+	}
+
+	public function column_action($item) {
+		$status = $item['status'];
+
+		printf('<div class="activitypub-settings-action-buttons">');
+
+		// TODO this can be written smarter, but at least it is readable.
+		if ( 'pending' === $status ) {
+			self::display_follow_request_action_button( $item['id'], 'approve');
+			self::display_follow_request_action_button( $item['id'], 'reject');
+			self::display_follow_request_action_button( $item['id'], 'delete', false);
+		}
+
+		if ( 'approved' === $status ) {
+			self::display_follow_request_action_button( $item['id'], 'approve', false);
+			self::display_follow_request_action_button( $item['id'], 'reject');
+			self::display_follow_request_action_button( $item['id'], 'delete', false);
+		}
+
+		if ( 'rejected' === $status ) {
+			self::display_follow_request_action_button( $item['id'], 'approve', false); // TODO: Clarify with Mobilizon
+			self::display_follow_request_action_button( $item['id'], 'reject', false);
+			self::display_follow_request_action_button( $item['id'], 'delete');
+		}
+
+		printf('</div>');
+	}
+
+	public function process_action() {
+		if ( ! isset( $_REQUEST['follow_requests'] ) || ! isset( $_REQUEST['_wpnonce'] ) ) {
+			return false;
+		}
+		$nonce = sanitize_text_field( wp_unslash( $_REQUEST['_wpnonce'] ) );
+		if ( ! wp_verify_nonce( $nonce, 'bulk-' . $this->_args['plural'] ) ) {
+			return false;
+		}
+
+		if ( ! current_user_can( 'edit_user', $this->user_id ) ) {
+			return false;
+		}
+
+		$follow_requests = $_REQUEST['follow_requests']; // phpcs:ignore
+
+		switch ( $this->current_action() ) {
+			case 'reject':
+				if ( ! is_array( $follow_requests ) ) {
+					$follow_requests = array( $follow_requests );
+				}
+				foreach ( $follow_requests as $follow_request ) {
+					Follow_Request::from_wp_id( $follow_request )->reject();
+				}
+				break;
+			case 'approve':
+				if ( ! is_array( $follow_requests ) ) {
+					$follow_requests = array( $follow_requests );
+				}
+				foreach ( $follow_requests as $follow_request ) {
+					Follow_Request::from_wp_id( $follow_request )->approve();
+				}
+				break;
+		}
+	}
+
+	public function follow_requests_count() {
+		return $this->follow_requests_count;
+	}
+}

includes/table/class-followers.php

@@ -5,6 +5,8 @@ use WP_List_Table;
 use Activitypub\Collection\Users;
 use Activitypub\Collection\Followers as FollowerCollection;
 
+use function Activitypub\object_to_uri;
+
 if ( ! \class_exists( '\WP_List_Table' ) ) {
 		require_once ABSPATH . 'wp-admin/includes/class-wp-list-table.php';
 }
@@ -101,7 +103,7 @@ class Followers extends WP_List_Table {
 				'icon'       => esc_attr( $follower->get_icon_url() ),
 				'post_title' => esc_attr( $follower->get_name() ),
 				'username'   => esc_attr( $follower->get_preferred_username() ),
-				'url'        => esc_attr( $follower->get_url() ),
+				'url'        => esc_attr( object_to_uri( $follower->get_url() ) ),
 				'identifier' => esc_attr( $follower->get_id() ),
 				'published'  => esc_attr( $follower->get_published() ),
 				'modified'   => esc_attr( $follower->get_updated() ),

includes/transformer/class-attachment.php

@@ -0,0 +1,49 @@
+<?php
+namespace Activitypub\Transformer;
+
+use Activitypub\Transformer\Post;
+
+/**
+ * WordPress Attachment Transformer
+ *
+ * The Attachment Transformer is responsible for transforming a WP_Post object into different other
+ * Object-Types.
+ *
+ * Currently supported are:
+ *
+ * - Activitypub\Activity\Base_Object
+ */
+class Attachment extends Post {
+	/**
+	 * Generates all Media Attachments for a Post.
+	 *
+	 * @return array The Attachments.
+	 */
+	protected function get_attachment() {
+		$mime_type  = get_post_mime_type( $this->object->ID );
+		$media_type = preg_replace( '/(\/[a-zA-Z]+)/i', '', $mime_type );
+
+		switch ( $media_type ) {
+			case 'audio':
+			case 'video':
+				$type = 'Document';
+				break;
+			case 'image':
+				$type = 'Image';
+				break;
+		}
+
+		$attachment = array(
+			'type'      => $type,
+			'url'       => wp_get_attachment_url( $this->object->ID ),
+			'mediaType' => $mime_type,
+		);
+
+		$alt = \get_post_meta( $this->object->ID, '_wp_attachment_image_alt', true );
+		if ( $alt ) {
+			$attachment['name'] = $alt;
+		}
+
+		return $attachment;
+	}
+}

includes/transformer/class-base.php

@@ -1,619 +1,105 @@
 <?php
-/**
- * Inspired by the PHP ActivityPub Library by @Landrok
- *
- * @link https://github.com/landrok/activitypub
- */
 namespace Activitypub\Transformer;
 
-use WP_Post;
+use Activitypub\Activity\Activity;
-use Activitypub\Collection\Users;
-use Activitypub\Model\Blog_User;
 use Activitypub\Activity\Base_Object;
-use Activitypub\Shortcodes;
-
-use function Activitypub\esc_hashtag;
-use function Activitypub\is_single_user;
-use function Activitypub\get_rest_url_by_path;
-use function Activitypub\site_supports_blocks;
 
 /**
- * Base class to implement WordPress to ActivityPub transformers.
+ * WordPress Base Transformer
+ *
+ * Transformers are responsible for transforming a WordPress objects into different ActivityPub
+ * Object-Types or Activities.
  */
 abstract class Base {
 	/**
 	 * The WP_Post object.
 	 *
-	 * @var WP_Post
+	 * @var
 	 */
-	protected $wp_post;
+	protected $object;
 
 	/**
-	 * Assign WP_Post Object to a specific transformer instance.
+	 * Static function to Transform a WordPress Object.
 	 *
 	 * This helps to chain the output of the Transformer.
 	 *
-	 * @param WP_Post $wp_post The WP_Post object.
+	 * @param stdClass $object The WP_Post object
+	 *
 	 * @return void
 	 */
-	public function set_wp_post( WP_Post $wp_post ) {
+	public static function transform( $object ) {
-		$post_type = get_post_type( $wp_post );
+		return new static( $object );
-		if ( ! $this->supports_post_type( $post_type ) ) {
-			_doing_it_wrong(
-				__METHOD__,
-				/* translators: %s: Block name. */
-				sprintf( 'The Transformer "%s" does not support the post type "%s".', esc_html( $this->get_label() ), esc_html( $post_type ) ),
-				'version_number_transformer_management_placeholder'
-			);
-		}
-		$this->wp_post = $wp_post;
 	}
 
 	/**
-	 * Get the supported WP post types that the transformer can use as an input.
+	 * Base constructor.
 	 *
-	 * By default all post types are supported.
+	 * @param stdClass $object
-	 * You may very likely wish to override this function.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @return string[] An array containing all the supported post types.
 	 */
-	public function get_supported_post_types() {
+	public function __construct( $object ) {
-		return \get_post_types( array( 'public' => true ), 'names' );
+		$this->object = $object;
 	}
 
 	/**
-	 * Get the name of the plugin that registered the transformer.
+	 * Transform the WordPress Object into an ActivityPub Object.
 	 *
-	 * @see Forked from the WordPress elementor plugin.
+	 * @return Activitypub\Activity\Base_Object
-	 * @since version_number_transformer_management_placeholder
-	 * @return string Plugin name
-	 */
-	private function get_plugin_name_from_transformer_instance( $transformer ) {
-		$class_reflection = new \ReflectionClass( $transformer );
-
-		$plugin_basename = plugin_basename( $class_reflection->getFileName() );
-
-		$plugin_directory = strtok( $plugin_basename, '/' );
-
-		$plugins_data = get_plugins( '/' . $plugin_directory );
-		$plugin_data  = array_shift( $plugins_data );
-
-		if ( isset( $plugin_data['Name'] ) ) {
-			return $plugin_data['Name'];
-		} else {
-			return esc_html__( 'Unknown', 'activitypub' );
-		}
-	}
-
-	/**
-	 * Return whether the transformer supports a post type.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @return string post_type Post type name.
-	 */
-	final public function supports_post_type( $post_type ) {
-		return in_array( $post_type, $this->get_supported_post_types(), true );
-	}
-
-	/**
-	 * Get the name used for registering the transformer with the ActivityPub plugin.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @return string name
-	 */
-	abstract public function get_name();
-
-	/**
-	 * Get the display name for the ActivityPub transformer.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @return string display name
-	 */
-	abstract public function get_label();
-
-	/**
-	 * Returns the ActivityStreams 2.0 Object-Type for a Post.
-	 *
-	 * @see https://www.w3.org/TR/activitystreams-vocabulary/#activity-types
-	 *
-	 * @return string The Object-Type.
-	 */
-	abstract protected function get_object_type();
-
-	/**
-	 * Returns the content for the ActivityPub Item.
-	 *
-	 * The content will be generated based on the user settings.
-	 *
-	 * @return string The content.
-	 */
-	protected function get_content() {
-		global $post;
-
-		/**
-		 * Provides an action hook so plugins can add their own hooks/filters before AP content is generated.
-		 *
-		 * Example: if a plugin adds a filter to `the_content` to add a button to the end of posts, it can also remove that filter here.
-		 *
-		 * @param WP_Post $post The post object.
-		 */
-		do_action( 'activitypub_before_get_content', $post );
-
-		// phpcs:ignore WordPress.WP.GlobalVariablesOverride.Prohibited
-		$post    = $this->wp_post;
-		$content = $this->get_post_content_template();
-
-		// Register our shortcodes just in time.
-		Shortcodes::register();
-		// Fill in the shortcodes.
-		setup_postdata( $post );
-		$content = do_shortcode( $content );
-		wp_reset_postdata();
-
-		$content = \wpautop( $content );
-		$content = \preg_replace( '/[\n\r\t]/', '', $content );
-		$content = \trim( $content );
-
-		$content = \apply_filters( 'activitypub_the_content', $content, $post );
-
-		// Don't need these any more, should never appear in a post.
-		Shortcodes::unregister();
-
-		return $content;
-	}
-
-	/**
-	 * Gets the template to use to generate the content of the activitypub item.
-	 *
-	 * @return string The Template.
-	 */
-	protected function get_post_content_template() {
-		if ( 'excerpt' === \get_option( 'activitypub_post_content_type', 'content' ) ) {
-			return "[ap_excerpt]\n\n[ap_permalink type=\"html\"]";
-		}
-
-		if ( 'title' === \get_option( 'activitypub_post_content_type', 'content' ) ) {
-			return "[ap_title]\n\n[ap_permalink type=\"html\"]";
-		}
-
-		if ( 'content' === \get_option( 'activitypub_post_content_type', 'content' ) ) {
-			return "[ap_content]\n\n[ap_permalink type=\"html\"]\n\n[ap_hashtags]";
-		}
-
-		return \get_option( 'activitypub_custom_post_content', ACTIVITYPUB_CUSTOM_POST_CONTENT );
-	}
-
-	/**
-	 * Returns the ID of the Post.
-	 *
-	 * @return string The Posts ID.
-	 */
-	public function get_id() {
-		return $this->get_url();
-	}
-
-	/**
-	 * Returns the URL of the Post.
-	 *
-	 * @return string The Posts URL.
-	 */
-	public function get_url() {
-		$post = $this->wp_post;
-
-		if ( 'trash' === get_post_status( $post ) ) {
-			$permalink = \get_post_meta( $post->ID, 'activitypub_canonical_url', true );
-		} else {
-			$permalink = \get_permalink( $post );
-		}
-
-		return \esc_url( $permalink );
-	}
-
-	/**
-	 * Returns the User-URL of the Author of the Post.
-	 *
-	 * If `single_user` mode is enabled, the URL of the Blog-User is returned.
-	 *
-	 * @return string The User-URL.
-	 */
-	protected function get_attributed_to() {
-		if ( is_single_user() ) {
-			$user = new Blog_User();
-			return $user->get_url();
-		}
-
-		return Users::get_by_id( $this->wp_post->post_author )->get_url();
-	}
-
-	/**
-	 * Generates all Media Attachments for a Post.
-	 *
-	 * @return array The Attachments.
-	 */
-	protected function get_attachments() {
-		// Once upon a time we only supported images, but we now support audio/video as well.
-		// We maintain the image-centric naming for backwards compatibility.
-		$max_media = intval( \apply_filters( 'activitypub_max_image_attachments', \get_option( 'activitypub_max_image_attachments', ACTIVITYPUB_MAX_IMAGE_ATTACHMENTS ) ) );
-
-		if ( site_supports_blocks() && \has_blocks( $this->wp_post->post_content ) ) {
-			return $this->get_block_attachments( $max_media );
-		}
-
-		return $this->get_classic_editor_images( $max_media );
-	}
-
-	/**
-	 * Get media attachments from blocks. They will be formatted as ActivityPub attachments, not as WP attachments.
-	 *
-	 * @param int $max_media The maximum number of attachments to return.
-	 *
-	 * @return array The attachments.
-	 */
-	protected function get_block_attachments( $max_media ) {
-		// max media can't be negative or zero
-		if ( $max_media <= 0 ) {
-			return array();
-		}
-
-		$id = $this->wp_post->ID;
-
-		$media_ids = array();
-
-		// list post thumbnail first if this post has one
-		if ( \function_exists( 'has_post_thumbnail' ) && \has_post_thumbnail( $id ) ) {
-			$media_ids[] = \get_post_thumbnail_id( $id );
-		}
-
-		if ( $max_media > 0 ) {
-			$blocks    = \parse_blocks( $this->wp_post->post_content );
-			$media_ids = self::get_media_ids_from_blocks( $blocks, $media_ids, $max_media );
-		}
-
-		return \array_filter( \array_map( array( self::class, 'wp_attachment_to_activity_attachment' ), $media_ids ) );
-	}
-
-	/**
-	 * Get image attachments from the classic editor.
-	 * Note that audio/video attachments are only supported in the block editor.
-	 *
-	 * @param int $max_images The maximum number of images to return.
-	 *
-	 * @return array The attachments.
-	 */
-	protected function get_classic_editor_images( $max_images ) {
-		// max images can't be negative or zero
-		if ( $max_images <= 0 ) {
-			return array();
-		}
-
-		$id = $this->wp_post->ID;
-
-		$image_ids = array();
-
-		// list post thumbnail first if this post has one
-		if ( \function_exists( 'has_post_thumbnail' ) && \has_post_thumbnail( $id ) ) {
-			$image_ids[] = \get_post_thumbnail_id( $id );
-			--$max_images;
-		}
-
-		if ( $max_images > 0 ) {
-			$query = new \WP_Query(
-				array(
-					'post_parent'    => $id,
-					'post_status'    => 'inherit',
-					'post_type'      => 'attachment',
-					'post_mime_type' => 'image',
-					'order'          => 'ASC',
-					'orderby'        => 'menu_order ID',
-					'posts_per_page' => $max_images,
-				)
-			);
-			foreach ( $query->get_posts() as $attachment ) {
-				if ( ! \in_array( $attachment->ID, $image_ids, true ) ) {
-					$image_ids[] = $attachment->ID;
-				}
-			}
-		}
-		$image_ids = \array_unique( $image_ids );
-
-		return \array_filter( \array_map( array( self::class, 'wp_attachment_to_activity_attachment' ), $image_ids ) );
-	}
-
-	/**
-	 * Recursively get media IDs from blocks.
-	 *
-	 * @param array $blocks The blocks to search for media IDs
-	 * @param array $media_ids The media IDs to append new IDs to
-	 * @param int   $max_media The maximum number of media to return.
-	 *
-	 * @return array The image IDs.
-	 */
-	protected static function get_media_ids_from_blocks( $blocks, $media_ids, $max_media ) {
-
-		foreach ( $blocks as $block ) {
-			// recurse into inner blocks
-			if ( ! empty( $block['innerBlocks'] ) ) {
-				$media_ids = self::get_media_ids_from_blocks( $block['innerBlocks'], $media_ids, $max_media );
-			}
-
-			switch ( $block['blockName'] ) {
-				case 'core/image':
-				case 'core/cover':
-				case 'core/audio':
-				case 'core/video':
-				case 'videopress/video':
-					if ( ! empty( $block['attrs']['id'] ) ) {
-						$media_ids[] = $block['attrs']['id'];
-					}
-					break;
-				case 'jetpack/slideshow':
-				case 'jetpack/tiled-gallery':
-					if ( ! empty( $block['attrs']['ids'] ) ) {
-						$media_ids = array_merge( $media_ids, $block['attrs']['ids'] );
-					}
-					break;
-				case 'jetpack/image-compare':
-					if ( ! empty( $block['attrs']['beforeImageId'] ) ) {
-						$media_ids[] = $block['attrs']['beforeImageId'];
-					}
-					if ( ! empty( $block['attrs']['afterImageId'] ) ) {
-						$media_ids[] = $block['attrs']['afterImageId'];
-					}
-					break;
-			}
-
-			// depupe
-			$media_ids = \array_unique( $media_ids );
-
-			// stop doing unneeded work
-			if ( count( $media_ids ) >= $max_media ) {
-				break;
-			}
-		}
-
-		// still need to slice it because one gallery could knock us over the limit
-		return array_slice( $media_ids, 0, $max_media );
-	}
-
-	/**
-	 * Converts a WordPress Attachment to an ActivityPub Attachment.
-	 *
-	 * @param int $id The Attachment ID.
-	 *
-	 * @return array The ActivityPub Attachment.
-	 */
-	public static function wp_attachment_to_activity_attachment( $id ) {
-		$attachment      = array();
-		$mime_type       = \get_post_mime_type( $id );
-		$mime_type_parts = \explode( '/', $mime_type );
-		// switching on image/audio/video
-		switch ( $mime_type_parts[0] ) {
-			case 'image':
-				$image_size = 'full';
-
-				/**
-				 * Filter the image URL returned for each post.
-				 *
-				 * @param array|false $thumbnail The image URL, or false if no image is available.
-				 * @param int         $id        The attachment ID.
-				 * @param string      $image_size The image size to retrieve. Set to 'full' by default.
-				 */
-				$thumbnail = apply_filters(
-					'activitypub_get_image',
-					self::get_image( $id, $image_size ),
-					$id,
-					$image_size
-				);
-
-				if ( $thumbnail ) {
-					$alt   = \get_post_meta( $id, '_wp_attachment_image_alt', true );
-					$image = array(
-						'type'      => 'Image',
-						'url'       => $thumbnail[0],
-						'mediaType' => $mime_type,
-					);
-
-					if ( $alt ) {
-						$image['name'] = $alt;
-					}
-					$attachment = $image;
-				}
-				break;
-
-			case 'audio':
-			case 'video':
-				$attachment = array(
-					'type'      => 'Document',
-					'mediaType' => $mime_type,
-					'url'       => \wp_get_attachment_url( $id ),
-					'name'      => \get_the_title( $id ),
-				);
-				$meta       = wp_get_attachment_metadata( $id );
-				// height and width for videos
-				if ( isset( $meta['width'] ) && isset( $meta['height'] ) ) {
-					$attachment['width']  = $meta['width'];
-					$attachment['height'] = $meta['height'];
-				}
-				// @todo: add `icon` support for audio/video attachments. Maybe use post thumbnail?
-				break;
-		}
-
-		return \apply_filters( 'activitypub_attachment', $attachment, $id );
-	}
-
-	/**
-	 * Return details about an image attachment.
-	 *
-	 * @param int    $id         The attachment ID.
-	 * @param string $image_size The image size to retrieve. Set to 'full' by default.
-	 *
-	 * @return array|false Array of image data, or boolean false if no image is available.
-	 */
-	protected static function get_image( $id, $image_size = 'full' ) {
-		/**
-		 * Hook into the image retrieval process. Before image retrieval.
-		 *
-		 * @param int    $id         The attachment ID.
-		 * @param string $image_size The image size to retrieve. Set to 'full' by default.
-		 */
-		do_action( 'activitypub_get_image_pre', $id, $image_size );
-
-		$image = \wp_get_attachment_image_src( $id, $image_size );
-
-		/**
-		 * Hook into the image retrieval process. After image retrieval.
-		 *
-		 * @param int    $id         The attachment ID.
-		 * @param string $image_size The image size to retrieve. Set to 'full' by default.
-		 */
-		do_action( 'activitypub_get_image_post', $id, $image_size );
-
-		return $image;
-	}
-
-
-	/**
-	 * Helper function to get the @-Mentions from the post content.
-	 *
-	 * @return array The list of @-Mentions.
-	 */
-	protected function get_mentions() {
-		return apply_filters( 'activitypub_extract_mentions', array(), $this->wp_post->post_content, $this->wp_post );
-	}
-
-		/**
-		 * Returns a list of Mentions, used in the Post.
-		 *
-		 * @see https://docs.joinmastodon.org/spec/activitypub/#Mention
-		 *
-		 * @return array The list of Mentions.
-		 */
-	protected function get_cc() {
-		$cc = array();
-
-		$mentions = $this->get_mentions();
-		if ( $mentions ) {
-			foreach ( $mentions as $url ) {
-				$cc[] = $url;
-			}
-		}
-
-		return $cc;
-	}
-
-	/**
-	 * Returns a list of Tags, used in the Post.
-	 *
-	 * This includes Hash-Tags and Mentions.
-	 *
-	 * @return array The list of Tags.
-	 */
-	protected function get_tags() {
-		$tags = array();
-
-		$post_tags = \get_the_tags( $this->wp_post->ID );
-		if ( $post_tags ) {
-			foreach ( $post_tags as $post_tag ) {
-				$tag    = array(
-					'type' => 'Hashtag',
-					'href' => \esc_url( \get_tag_link( $post_tag->term_id ) ),
-					'name' => esc_hashtag( $post_tag->name ),
-				);
-				$tags[] = $tag;
-			}
-		}
-
-		$mentions = $this->get_mentions();
-		if ( $mentions ) {
-			foreach ( $mentions as $mention => $url ) {
-				$tag    = array(
-					'type' => 'Mention',
-					'href' => \esc_url( $url ),
-					'name' => \esc_html( $mention ),
-				);
-				$tags[] = $tag;
-			}
-		}
-
-		return $tags;
-	}
-
-
-	/**
-	 * Returns the locale of the post.
-	 *
-	 * @return string The locale of the post.
-	 */
-	public function get_locale() {
-		$post_id = $this->wp_post->ID;
-		$lang    = \strtolower( \strtok( \get_locale(), '_-' ) );
-
-		/**
-		 * Filter the locale of the post.
-		 *
-		 * @param string  $lang    The locale of the post.
-		 * @param int     $post_id The post ID.
-		 * @param WP_Post $post    The post object.
-		 *
-		 * @return string The filtered locale of the post.
-		 */
-		return apply_filters( 'activitypub_post_locale', $lang, $post_id, $this->wp_post );
-	}
-
-	/**
-	 * Gets the contentMap
-	 *
-	 * @see https://www.w3.org/TR/activitystreams-vocabulary/#dfn-contentmap
-	 *
-	 * @return array the contenmap
-	 */
-	protected function get_content_map() {
-		return array(
-			$this->get_locale() => $this->get_content(),
-		);
-	}
-
-	/**
-	 * Transforms the WP_Post object to an ActivityPub Object
-	 *
-	 * @see \Activitypub\Activity\Base_Object
-	 *
-	 * @return \Activitypub\Activity\Base_Object The ActivityPub Object
 	 */
 	public function to_object() {
-		$wp_post = $this->wp_post;
 		$object = new Base_Object();
 
-		$object->set_id( $this->get_id() );
+		$vars = $object->get_object_var_keys();
-		$object->set_url( $this->get_url() );
-		$object->set_type( $this->get_object_type() );
 
-		$published = \strtotime( $wp_post->post_date_gmt );
+		foreach ( $vars as $var ) {
+			$getter = 'get_' . $var;
 
-		$object->set_published( \gmdate( 'Y-m-d\TH:i:s\Z', $published ) );
+			if ( method_exists( $this, $getter ) ) {
+				$value = call_user_func( array( $this, $getter ) );
 
-		$updated = \strtotime( $wp_post->post_modified_gmt );
+				if ( isset( $value ) ) {
+					$setter = 'set_' . $var;
 
-		if ( $updated > $published ) {
+					call_user_func( array( $object, $setter ), $value );
-			$object->set_updated( \gmdate( 'Y-m-d\TH:i:s\Z', $updated ) );
+				}
+			}
 		}
-
-		$object->set_attributed_to( $this->get_attributed_to() );
-		$object->set_content( $this->get_content() );
-		$object->set_content_map( $this->get_content_map );
-		$path = sprintf( 'users/%d/followers', intval( $wp_post->post_author ) );
-
-		$object->set_to(
-			array(
-				'https://www.w3.org/ns/activitystreams#Public',
-				get_rest_url_by_path( $path ),
-			)
-		);
-		$object->set_cc( $this->get_cc() );
-		$object->set_attachment( $this->get_attachments() );
-		$object->set_tag( $this->get_tags() );
 
 		return $object;
 	}
+
+	/**
+	 * Transforms the ActivityPub Object to an Activity
+	 *
+	 * @param string $type The Activity-Type.
+	 *
+	 * @return \Activitypub\Activity\Activity The Activity.
+	 */
+	public function to_activity( $type ) {
+		$object = $this->to_object();
+
+		$activity = new Activity();
+		$activity->set_type( $type );
+		$activity->set_object( $object );
+
+		// Use simple Object (only ID-URI) for Like and Announce
+		if ( in_array( $type, array( 'Like', 'Announce' ), true ) ) {
+			$activity->set_object( $object->get_id() );
+		}
+
+		return $activity;
+	}
+
+	/**
+	 * Returns the ID of the WordPress Object.
+	 *
+	 * @return int The ID of the WordPress Object
+	 */
+	abstract public function get_wp_user_id();
+
+	/**
+	 * Change the User-ID of the WordPress Post.
+	 *
+	 * @return int The User-ID of the WordPress Post
+	 */
+	abstract public function change_wp_user_id( $user_id );
 }

includes/transformer/class-comment.php

@@ -0,0 +1,277 @@
+<?php
+namespace Activitypub\Transformer;
+
+use WP_Comment;
+use WP_Comment_Query;
+use Activitypub\Hashtag;
+use Activitypub\Webfinger;
+use Activitypub\Model\Blog_User;
+use Activitypub\Collection\Users;
+use Activitypub\Transformer\Base;
+use Activitypub\Activity\Base_Object;
+
+use function Activitypub\esc_hashtag;
+use function Activitypub\is_single_user;
+use function Activitypub\get_rest_url_by_path;
+
+/**
+ * WordPress Comment Transformer
+ *
+ * The Comment Transformer is responsible for transforming a WP_Comment object into different
+ * Object-Types.
+ *
+ * Currently supported are:
+ *
+ * - Activitypub\Activity\Base_Object
+ */
+class Comment extends Base {
+	/**
+	 * Returns the User-ID of the WordPress Comment.
+	 *
+	 * @return int The User-ID of the WordPress Comment
+	 */
+	public function get_wp_user_id() {
+		return $this->object->user_id;
+	}
+
+	/**
+	 * Change the User-ID of the WordPress Comment.
+	 *
+	 * @return int The User-ID of the WordPress Comment
+	 */
+	public function change_wp_user_id( $user_id ) {
+		$this->object->user_id = $user_id;
+	}
+
+	/**
+	 * Transforms the WP_Comment object to an ActivityPub Object
+	 *
+	 * @see \Activitypub\Activity\Base_Object
+	 *
+	 * @return \Activitypub\Activity\Base_Object The ActivityPub Object
+	 */
+	public function to_object() {
+		$comment = $this->object;
+		$object  = parent::to_object();
+
+		$object->set_url( \get_comment_link( $comment->comment_ID ) );
+		$object->set_type( 'Note' );
+
+		$published = \strtotime( $comment->comment_date_gmt );
+		$object->set_published( \gmdate( 'Y-m-d\TH:i:s\Z', $published ) );
+
+		$updated = \get_comment_meta( $comment->comment_ID, 'activitypub_last_modified', true );
+		if ( $updated > $published ) {
+			$object->set_updated( \gmdate( 'Y-m-d\TH:i:s\Z', \strtotime( $updated ) ) );
+		}
+
+		$object->set_content_map(
+			array(
+				$this->get_locale() => $this->get_content(),
+			)
+		);
+		$path = sprintf( 'users/%d/followers', intval( $comment->comment_author ) );
+
+		$object->set_to(
+			array(
+				'https://www.w3.org/ns/activitystreams#Public',
+				get_rest_url_by_path( $path ),
+			)
+		);
+
+		return $object;
+	}
+
+	/**
+	 * Returns the User-URL of the Author of the Post.
+	 *
+	 * If `single_user` mode is enabled, the URL of the Blog-User is returned.
+	 *
+	 * @return string The User-URL.
+	 */
+	protected function get_attributed_to() {
+		if ( is_single_user() ) {
+			$user = new Blog_User();
+			return $user->get_url();
+		}
+
+		return Users::get_by_id( $this->object->user_id )->get_url();
+	}
+
+	/**
+	 * Returns the content for the ActivityPub Item.
+	 *
+	 * The content will be generated based on the user settings.
+	 *
+	 * @return string The content.
+	 */
+	protected function get_content() {
+		// phpcs:ignore WordPress.WP.GlobalVariablesOverride.Prohibited
+		$comment = $this->object;
+		$content = $comment->comment_content;
+
+		$content = \wpautop( $content );
+		$content = \preg_replace( '/[\n\r\t]/', '', $content );
+		$content = \trim( $content );
+		$content = \apply_filters( 'the_content', $content, $comment );
+
+		return $content;
+	}
+
+	/**
+	 * Returns the in-reply-to for the ActivityPub Item.
+	 *
+	 * @return int The URL of the in-reply-to.
+	 */
+	protected function get_in_reply_to() {
+		$comment = $this->object;
+
+		$parent_comment = \get_comment( $comment->comment_parent );
+
+		if ( $parent_comment ) {
+			$comment_meta = \get_comment_meta( $parent_comment->comment_ID );
+
+			if ( ! empty( $comment_meta['source_id'][0] ) ) {
+				$in_reply_to = $comment_meta['source_id'][0];
+			} elseif ( ! empty( $comment_meta['source_url'][0] ) ) {
+				$in_reply_to = $comment_meta['source_url'][0];
+			} else {
+				$in_reply_to = $this->generate_id( $parent_comment );
+			}
+		} else {
+			$in_reply_to = \get_permalink( $comment->comment_post_ID );
+		}
+
+		return $in_reply_to;
+	}
+
+	/**
+	 * Returns the ID of the ActivityPub Object.
+	 *
+	 * @see https://www.w3.org/TR/activitypub/#obj-id
+	 * @see https://github.com/tootsuite/mastodon/issues/13879
+	 *
+	 * @return string ActivityPub URI for comment
+	 */
+	protected function get_id() {
+		$comment = $this->object;
+		return $this->generate_id( $comment );
+	}
+
+	/**
+	 * Generates an ActivityPub URI for a comment
+	 *
+	 * @param WP_Comment|int $comment A comment object or comment ID
+	 *
+	 * @return string ActivityPub URI for comment
+	 */
+	protected function generate_id( $comment ) {
+		$comment = get_comment( $comment );
+
+		return \add_query_arg(
+			array(
+				'c' => $comment->comment_ID,
+			),
+			\trailingslashit( site_url() )
+		);
+	}
+
+	/**
+	 * Returns a list of Mentions, used in the Comment.
+	 *
+	 * @see https://docs.joinmastodon.org/spec/activitypub/#Mention
+	 *
+	 * @return array The list of Mentions.
+	 */
+	protected function get_cc() {
+		$cc = array();
+
+		$mentions = $this->get_mentions();
+		if ( $mentions ) {
+			foreach ( $mentions as $mention => $url ) {
+				$cc[] = $url;
+			}
+		}
+
+		$comment_query = new WP_Comment_Query(
+			array(
+				'post_id'    => $this->object->comment_post_ID,
+				// phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_query
+				'meta_query' => array(
+					array(
+						'key'     => 'source_id',
+						'compare' => 'EXISTS',
+					),
+				),
+			)
+		);
+
+		if ( $comment_query->comments ) {
+			foreach ( $comment_query->comments as $comment ) {
+				if ( empty( $comment->comment_author_url ) ) {
+					continue;
+				}
+				$cc[] = \esc_url( $comment->comment_author_url );
+			}
+		}
+
+		$cc = \array_unique( $cc );
+
+		return $cc;
+	}
+
+	/**
+	 * Returns a list of Tags, used in the Comment.
+	 *
+	 * This includes Hash-Tags and Mentions.
+	 *
+	 * @return array The list of Tags.
+	 */
+	protected function get_tag() {
+		$tags = array();
+
+		$mentions = $this->get_mentions();
+		if ( $mentions ) {
+			foreach ( $mentions as $mention => $url ) {
+				$tag = array(
+					'type' => 'Mention',
+					'href' => \esc_url( $url ),
+					'name' => \esc_html( $mention ),
+				);
+				$tags[] = $tag;
+			}
+		}
+
+		return \array_unique( $tags, SORT_REGULAR );
+	}
+
+	/**
+	 * Helper function to get the @-Mentions from the comment content.
+	 *
+	 * @return array The list of @-Mentions.
+	 */
+	protected function get_mentions() {
+		return apply_filters( 'activitypub_extract_mentions', array(), $this->object->comment_content, $this->object );
+	}
+
+	/**
+	 * Returns the locale of the post.
+	 *
+	 * @return string The locale of the post.
+	 */
+	public function get_locale() {
+		$comment_id = $this->object->ID;
+		$lang       = \strtolower( \strtok( \get_locale(), '_-' ) );
+
+		/**
+		 * Filter the locale of the comment.
+		 *
+		 * @param string  $lang    The locale of the comment.
+		 * @param int     $comment_id The comment ID.
+		 * @param WP_Post $post    The comment object.
+		 *
+		 * @return string The filtered locale of the comment.
+		 */
+		return apply_filters( 'activitypub_comment_locale', $lang, $comment_id, $this->object );
+	}
+}

includes/transformer/class-factory.php

@@ -0,0 +1,61 @@
+<?php
+namespace Activitypub\Transformer;
+
+use Activitypub\Transformer\Post;
+use Activitypub\Transformer\Comment;
+use Activitypub\Transformer\Attachment;
+
+/**
+ * Transformer Factory
+ */
+class Factory {
+	public static function get_transformer( $object ) {
+		/**
+		 * Filter the transformer for a given object.
+		 *
+		 * Add your own transformer based on the object class or the object type.
+		 *
+		 * Example usage:
+		 *
+		 * // Filter be object class
+		 * add_filter( 'activitypub_transformer', function( $transformer, $object, $object_class ) {
+		 *     if ( $object_class === 'WP_Post' ) {
+		 *         return new My_Post_Transformer( $object );
+		 *     }
+		 *     return $transformer;
+		 * }, 10, 3 );
+		 *
+		 * // Filter be object type
+		 * add_filter( 'activitypub_transformer', function( $transformer, $object, $object_class ) {
+		 *     if ( $object->post_type === 'event' ) {
+		 *         return new My_Event_Transformer( $object );
+		 *     }
+		 *     return $transformer;
+		 * }, 10, 3 );
+		 *
+		 * @param Activitypub\Transformer\Base $transformer  The transformer to use.
+		 * @param mixed                        $object       The object to transform.
+		 * @param string                       $object_class The class of the object to transform.
+		 *
+		 * @return mixed The transformer to use.
+		 */
+		$transformer = apply_filters( 'activitypub_transformer', null, $object, get_class( $object ) );
+
+		if ( $transformer ) {
+			return $transformer;
+		}
+
+		// use default transformer
+		switch ( get_class( $object ) ) {
+			case 'WP_Post':
+				if ( 'attachment' === $object->post_type ) {
+					return new Attachment( $object );
+				}
+				return new Post( $object );
+			case 'WP_Comment':
+				return new Comment( $object );
+			default:
+				return null;
+		}
+	}
+}

includes/transformer/class-post.php

@@ -2,11 +2,11 @@
 namespace Activitypub\Transformer;
 
 use WP_Post;
-use Activitypub\Collection\Users;
-use Activitypub\Model\Blog_User;
-use Activitypub\Activity\Base_Object;
 use Activitypub\Shortcodes;
+use Activitypub\Model\Blog_User;
 use Activitypub\Transformer\Base;
+use Activitypub\Collection\Users;
+use Activitypub\Activity\Base_Object;
 
 use function Activitypub\esc_hashtag;
 use function Activitypub\is_single_user;
@@ -15,29 +15,358 @@ use function Activitypub\site_supports_blocks;
 
 /**
  * WordPress Post Transformer
- * The Post Transformer is responsible for transforming a WP_Post object into different othe
+ *
+ * The Post Transformer is responsible for transforming a WP_Post object into different other
  * Object-Types.
  *
  * Currently supported are:
+ *
  * - Activitypub\Activity\Base_Object
  */
 class Post extends Base {
 	/**
-	 * Getter function for the name of the transformer.
+	 * Returns the ID of the WordPress Post.
 	 *
-	 * @return string name
+	 * @return int The ID of the WordPress Post
 	 */
-	public function get_name() {
+	public function get_wp_user_id() {
-		return 'activitypub/default';
+		return $this->object->post_author;
 	}
 
 	/**
-	 * Getter function for the display name (label/title) of the transformer.
+	 * Change the User-ID of the WordPress Post.
 	 *
-	 * @return string name
+	 * @return int The User-ID of the WordPress Post
 	 */
-	public function get_label() {
+	public function change_wp_user_id( $user_id ) {
-		return 'Built-In';
+		$this->object->post_author = $user_id;
+
+		return $this;
+	}
+
+	/**
+	 * Transforms the WP_Post object to an ActivityPub Object
+	 *
+	 * @see \Activitypub\Activity\Base_Object
+	 *
+	 * @return \Activitypub\Activity\Base_Object The ActivityPub Object
+	 */
+	public function to_object() {
+		$post = $this->object;
+		$object = parent::to_object();
+
+		$published = \strtotime( $post->post_date_gmt );
+
+		$object->set_published( \gmdate( 'Y-m-d\TH:i:s\Z', $published ) );
+
+		$updated = \strtotime( $post->post_modified_gmt );
+
+		if ( $updated > $published ) {
+			$object->set_updated( \gmdate( 'Y-m-d\TH:i:s\Z', $updated ) );
+		}
+
+		$object->set_content_map(
+			array(
+				$this->get_locale() => $this->get_content(),
+			)
+		);
+		$path = sprintf( 'users/%d/followers', intval( $post->post_author ) );
+
+		$object->set_to(
+			array(
+				'https://www.w3.org/ns/activitystreams#Public',
+				get_rest_url_by_path( $path ),
+			)
+		);
+
+		return $object;
+	}
+
+	/**
+	 * Returns the ID of the Post.
+	 *
+	 * @return string The Posts ID.
+	 */
+	public function get_id() {
+		return $this->get_url();
+	}
+
+	/**
+	 * Returns the URL of the Post.
+	 *
+	 * @return string The Posts URL.
+	 */
+	public function get_url() {
+		$post = $this->object;
+
+		if ( 'trash' === get_post_status( $post ) ) {
+			$permalink = \get_post_meta( $post->ID, 'activitypub_canonical_url', true );
+		} else {
+			$permalink = \get_permalink( $post );
+		}
+
+		return \esc_url( $permalink );
+	}
+
+	/**
+	 * Returns the User-URL of the Author of the Post.
+	 *
+	 * If `single_user` mode is enabled, the URL of the Blog-User is returned.
+	 *
+	 * @return string The User-URL.
+	 */
+	protected function get_attributed_to() {
+		if ( is_single_user() ) {
+			$user = new Blog_User();
+			return $user->get_url();
+		}
+
+		return Users::get_by_id( $this->object->post_author )->get_url();
+	}
+
+	/**
+	 * Generates all Media Attachments for a Post.
+	 *
+	 * @return array The Attachments.
+	 */
+	protected function get_attachment() {
+		// Once upon a time we only supported images, but we now support audio/video as well.
+		// We maintain the image-centric naming for backwards compatibility.
+		$max_media = intval( \apply_filters( 'activitypub_max_image_attachments', \get_option( 'activitypub_max_image_attachments', ACTIVITYPUB_MAX_IMAGE_ATTACHMENTS ) ) );
+
+		if ( site_supports_blocks() && \has_blocks( $this->object->post_content ) ) {
+			return $this->get_block_attachments( $max_media );
+		}
+
+		return $this->get_classic_editor_images( $max_media );
+	}
+
+	/**
+	 * Get media attachments from blocks. They will be formatted as ActivityPub attachments, not as WP attachments.
+	 *
+	 * @param int $max_media The maximum number of attachments to return.
+	 *
+	 * @return array The attachments.
+	 */
+	protected function get_block_attachments( $max_media ) {
+		// max media can't be negative or zero
+		if ( $max_media <= 0 ) {
+			return array();
+		}
+
+		$id = $this->object->ID;
+
+		$media_ids = array();
+
+		// list post thumbnail first if this post has one
+		if ( \function_exists( 'has_post_thumbnail' ) && \has_post_thumbnail( $id ) ) {
+			$media_ids[] = \get_post_thumbnail_id( $id );
+		}
+
+		if ( $max_media > 0 ) {
+			$blocks = \parse_blocks( $this->object->post_content );
+			$media_ids = self::get_media_ids_from_blocks( $blocks, $media_ids, $max_media );
+		}
+
+		return \array_filter( \array_map( array( self::class, 'wp_attachment_to_activity_attachment' ), $media_ids ) );
+	}
+
+	/**
+	 * Get image attachments from the classic editor.
+	 * Note that audio/video attachments are only supported in the block editor.
+	 *
+	 * @param int $max_images The maximum number of images to return.
+	 *
+	 * @return array The attachments.
+	 */
+	protected function get_classic_editor_images( $max_images ) {
+		// max images can't be negative or zero
+		if ( $max_images <= 0 ) {
+			return array();
+		}
+
+		$id = $this->object->ID;
+
+		$image_ids = array();
+
+		// list post thumbnail first if this post has one
+		if ( \function_exists( 'has_post_thumbnail' ) && \has_post_thumbnail( $id ) ) {
+			$image_ids[] = \get_post_thumbnail_id( $id );
+			--$max_images;
+		}
+
+		if ( $max_images > 0 ) {
+			$query = new \WP_Query(
+				array(
+					'post_parent' => $id,
+					'post_status' => 'inherit',
+					'post_type' => 'attachment',
+					'post_mime_type' => 'image',
+					'order' => 'ASC',
+					'orderby' => 'menu_order ID',
+					'posts_per_page' => $max_images,
+				)
+			);
+			foreach ( $query->get_posts() as $attachment ) {
+				if ( ! \in_array( $attachment->ID, $image_ids, true ) ) {
+					$image_ids[] = $attachment->ID;
+				}
+			}
+		}
+		$image_ids = \array_unique( $image_ids );
+
+		return \array_filter( \array_map( array( self::class, 'wp_attachment_to_activity_attachment' ), $image_ids ) );
+	}
+
+	/**
+	 * Recursively get media IDs from blocks.
+	 * @param array $blocks The blocks to search for media IDs
+	 * @param array $media_ids The media IDs to append new IDs to
+	 * @param int $max_media The maximum number of media to return.
+	 *
+	 * @return array The image IDs.
+	 */
+	protected static function get_media_ids_from_blocks( $blocks, $media_ids, $max_media ) {
+
+		foreach ( $blocks as $block ) {
+			// recurse into inner blocks
+			if ( ! empty( $block['innerBlocks'] ) ) {
+				$media_ids = self::get_media_ids_from_blocks( $block['innerBlocks'], $media_ids, $max_media );
+			}
+
+			switch ( $block['blockName'] ) {
+				case 'core/image':
+				case 'core/cover':
+				case 'core/audio':
+				case 'core/video':
+				case 'videopress/video':
+					if ( ! empty( $block['attrs']['id'] ) ) {
+						$media_ids[] = $block['attrs']['id'];
+					}
+					break;
+				case 'jetpack/slideshow':
+				case 'jetpack/tiled-gallery':
+					if ( ! empty( $block['attrs']['ids'] ) ) {
+						$media_ids = array_merge( $media_ids, $block['attrs']['ids'] );
+					}
+					break;
+				case 'jetpack/image-compare':
+					if ( ! empty( $block['attrs']['beforeImageId'] ) ) {
+						$media_ids[] = $block['attrs']['beforeImageId'];
+					}
+					if ( ! empty( $block['attrs']['afterImageId'] ) ) {
+						$media_ids[] = $block['attrs']['afterImageId'];
+					}
+					break;
+			}
+
+			// depupe
+			$media_ids = \array_unique( $media_ids );
+
+			// stop doing unneeded work
+			if ( count( $media_ids ) >= $max_media ) {
+				break;
+			}
+		}
+
+		// still need to slice it because one gallery could knock us over the limit
+		return array_slice( $media_ids, 0, $max_media );
+	}
+
+	/**
+	 * Converts a WordPress Attachment to an ActivityPub Attachment.
+	 *
+	 * @param int $id The Attachment ID.
+	 *
+	 * @return array The ActivityPub Attachment.
+	 */
+	public static function wp_attachment_to_activity_attachment( $id ) {
+		$attachment = array();
+		$mime_type = \get_post_mime_type( $id );
+		$mime_type_parts = \explode( '/', $mime_type );
+		// switching on image/audio/video
+		switch ( $mime_type_parts[0] ) {
+			case 'image':
+				$image_size = 'full';
+
+				/**
+				 * Filter the image URL returned for each post.
+				 *
+				 * @param array|false $thumbnail The image URL, or false if no image is available.
+				 * @param int         $id        The attachment ID.
+				 * @param string      $image_size The image size to retrieve. Set to 'full' by default.
+				 */
+				$thumbnail = apply_filters(
+					'activitypub_get_image',
+					self::get_wordpress_attachment( $id, $image_size ),
+					$id,
+					$image_size
+				);
+
+				if ( $thumbnail ) {
+					$alt   = \get_post_meta( $id, '_wp_attachment_image_alt', true );
+					$image = array(
+						'type'      => 'Image',
+						'url'       => $thumbnail[0],
+						'mediaType' => $mime_type,
+					);
+
+					if ( $alt ) {
+						$image['name'] = $alt;
+					}
+					$attachment = $image;
+				}
+				break;
+
+			case 'audio':
+			case 'video':
+				$attachment = array(
+					'type'      => 'Document',
+					'mediaType' => $mime_type,
+					'url'       => \wp_get_attachment_url( $id ),
+					'name'      => \get_the_title( $id ),
+				);
+				$meta = wp_get_attachment_metadata( $id );
+				// height and width for videos
+				if ( isset( $meta['width'] ) && isset( $meta['height'] ) ) {
+					$attachment['width'] = $meta['width'];
+					$attachment['height'] = $meta['height'];
+				}
+				// @todo: add `icon` support for audio/video attachments. Maybe use post thumbnail?
+				break;
+		}
+
+		return \apply_filters( 'activitypub_attachment', $attachment, $id );
+	}
+
+	/**
+	 * Return details about an image attachment.
+	 *
+	 * @param int    $id         The attachment ID.
+	 * @param string $image_size The image size to retrieve. Set to 'full' by default.
+	 *
+	 * @return array|false Array of image data, or boolean false if no image is available.
+	 */
+	protected static function get_wordpress_attachment( $id, $image_size = 'full' ) {
+		/**
+		 * Hook into the image retrieval process. Before image retrieval.
+		 *
+		 * @param int    $id         The attachment ID.
+		 * @param string $image_size The image size to retrieve. Set to 'full' by default.
+		 */
+		do_action( 'activitypub_get_image_pre', $id, $image_size );
+
+		$image = \wp_get_attachment_image_src( $id, $image_size );
+
+		/**
+		 * Hook into the image retrieval process. After image retrieval.
+		 *
+		 * @param int    $id         The attachment ID.
+		 * @param string $image_size The image size to retrieve. Set to 'full' by default.
+		 */
+		do_action( 'activitypub_get_image_post', $id, $image_size );
+
+		return $image;
 	}
 
 	/**
@@ -48,17 +377,17 @@ class Post extends Base {
 	 *
 	 * @return string The Object-Type.
 	 */
-	protected function get_object_type() {
+	protected function get_type() {
 		if ( 'wordpress-post-format' !== \get_option( 'activitypub_object_type', 'note' ) ) {
 			return \ucfirst( \get_option( 'activitypub_object_type', 'note' ) );
 		}
 
 		// Default to Article.
 		$object_type = 'Article';
-		$post_type   = \get_post_type( $this->wp_post );
+		$post_type = \get_post_type( $this->object );
 		switch ( $post_type ) {
 			case 'post':
-				$post_format = \get_post_format( $this->wp_post );
+				$post_format = \get_post_format( $this->object );
 				switch ( $post_format ) {
 					case 'aside':
 					case 'status':
@@ -106,4 +435,159 @@ class Post extends Base {
 
 		return $object_type;
 	}
+
+	/**
+	 * Returns a list of Mentions, used in the Post.
+	 *
+	 * @see https://docs.joinmastodon.org/spec/activitypub/#Mention
+	 *
+	 * @return array The list of Mentions.
+	 */
+	protected function get_cc() {
+		$cc = array();
+
+		$mentions = $this->get_mentions();
+		if ( $mentions ) {
+			foreach ( $mentions as $url ) {
+				$cc[] = $url;
+			}
+		}
+
+		return $cc;
+	}
+
+	/**
+	 * Returns a list of Tags, used in the Post.
+	 *
+	 * This includes Hash-Tags and Mentions.
+	 *
+	 * @return array The list of Tags.
+	 */
+	protected function get_tag() {
+		$tags = array();
+
+		$post_tags = \get_the_tags( $this->object->ID );
+		if ( $post_tags ) {
+			foreach ( $post_tags as $post_tag ) {
+				$tag = array(
+					'type' => 'Hashtag',
+					'href' => \esc_url( \get_tag_link( $post_tag->term_id ) ),
+					'name' => esc_hashtag( $post_tag->name ),
+				);
+				$tags[] = $tag;
+			}
+		}
+
+		$mentions = $this->get_mentions();
+		if ( $mentions ) {
+			foreach ( $mentions as $mention => $url ) {
+				$tag = array(
+					'type' => 'Mention',
+					'href' => \esc_url( $url ),
+					'name' => \esc_html( $mention ),
+				);
+				$tags[] = $tag;
+			}
+		}
+
+		return $tags;
+	}
+
+	/**
+	 * Returns the content for the ActivityPub Item.
+	 *
+	 * The content will be generated based on the user settings.
+	 *
+	 * @return string The content.
+	 */
+	protected function get_content() {
+		global $post;
+
+		/**
+		 * Provides an action hook so plugins can add their own hooks/filters before AP content is generated.
+		 *
+		 * Example: if a plugin adds a filter to `the_content` to add a button to the end of posts, it can also remove that filter here.
+		 *
+		 * @param WP_Post $post The post object.
+		 */
+		do_action( 'activitypub_before_get_content', $post );
+
+		// phpcs:ignore WordPress.WP.GlobalVariablesOverride.Prohibited
+		$post    = $this->object;
+		$content = $this->get_post_content_template();
+
+		// Register our shortcodes just in time.
+		Shortcodes::register();
+		// Fill in the shortcodes.
+		setup_postdata( $post );
+		$content = do_shortcode( $content );
+		wp_reset_postdata();
+
+		$content = \wpautop( $content );
+		$content = \preg_replace( '/[\n\r\t]/', '', $content );
+		$content = \trim( $content );
+
+		$content = \apply_filters( 'activitypub_the_content', $content, $post );
+
+		// Don't need these any more, should never appear in a post.
+		Shortcodes::unregister();
+
+		return $content;
+	}
+
+	/**
+	 * Gets the template to use to generate the content of the activitypub item.
+	 *
+	 * @return string The Template.
+	 */
+	protected function get_post_content_template() {
+		$type = \get_option( 'activitypub_post_content_type', 'content' );
+
+		switch ( $type ) {
+			case 'excerpt':
+				$template = "[ap_excerpt]\n\n[ap_permalink type=\"html\"]";
+				break;
+			case 'title':
+				$template = "[ap_title]\n\n[ap_permalink type=\"html\"]";
+				break;
+			case 'content':
+				$template = "[ap_content]\n\n[ap_permalink type=\"html\"]\n\n[ap_hashtags]";
+				break;
+			default:
+				$template = \get_option( 'activitypub_custom_post_content', ACTIVITYPUB_CUSTOM_POST_CONTENT );
+				break;
+		}
+
+		return apply_filters( 'activitypub_object_content_template', $template, $this->object );
+	}
+
+	/**
+	 * Helper function to get the @-Mentions from the post content.
+	 *
+	 * @return array The list of @-Mentions.
+	 */
+	protected function get_mentions() {
+		return apply_filters( 'activitypub_extract_mentions', array(), $this->object->post_content, $this->object );
+	}
+
+	/**
+	 * Returns the locale of the post.
+	 *
+	 * @return string The locale of the post.
+	 */
+	public function get_locale() {
+		$post_id = $this->object->ID;
+		$lang    = \strtolower( \strtok( \get_locale(), '_-' ) );
+
+		/**
+		 * Filter the locale of the post.
+		 *
+		 * @param string  $lang    The locale of the post.
+		 * @param int     $post_id The post ID.
+		 * @param WP_Post $post    The post object.
+		 *
+		 * @return string The filtered locale of the post.
+		 */
+		return apply_filters( 'activitypub_post_locale', $lang, $post_id, $this->object );
+	}
 }

includes/transformer/class-transformers-manager.php

@@ -1,292 +0,0 @@
-<?php
-/**
- * Inspired by the way elementor handles addons.
- *
- * @link https://github.com/elementor/elementor/
- * @package Activitypub
- */
-
-namespace Activitypub\Transformer;
-
-use WP_Post;
-use WP_Comment;
-
-use function Activitypub\camel_to_snake_case;
-use function Activitypub\snake_to_camel_case;
-
-if ( ! defined( 'ABSPATH' ) ) {
-	exit; // Exit if accessed directly.
-}
-
-/**
- * ActivityPub transformers manager.
- *
- * ActivityPub transformers manager handler class is responsible for registering and
- * initializing all the supported WP-Pobject to ActivityPub transformers.
- *
- * @since version_number_transformer_management_placeholder
- */
-class Transformers_Manager {
-	const DEFAULT_TRANSFORMER_MAPPING = array(
-		'post' => ACTIVITYPUB_DEFAULT_TRANSFORMER,
-		'page' => ACTIVITYPUB_DEFAULT_TRANSFORMER,
-	);
-
-	/**
-	 * Transformers.
-	 *
-	 * Holds the list of all the ActivityPub transformers. Default is `null`.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @access private
-	 *
-	 * @var \ActivityPub\Transformer\Base[]
-	 */
-	private $transformers = null;
-
-	/**
-	 * Transformer_Manager instance.
-	 *
-	 * Holds the transformer instance.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @access protected
-	 *
-	 * @var Transformer_Manager
-	 */
-	protected static $_instances = [];
-
-
-	/**
-	 * Instance.
-	 *
-	 * Ensures only one instance of the transformer manager class is loaded or can be loaded.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @access public
-	 * @static
-	 *
-	 * @return Transformer_Manager An instance of the class.
-	 */
-	public static function instance() {
-		$class_name = static::class_name();
-
-		if ( empty( static::$_instances[ $class_name ] ) ) {
-			static::$_instances[ $class_name ] = new static();
-		}
-
-		return static::$_instances[ $class_name ];
-	}
-
-	/**
-	 * Class name.
-	 *
-	 * Retrieve the name of the class.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @access public
-	 * @static
-	 */
-	public static function class_name() {
-		return get_called_class();
-	}
-
-	/**
-	 * Transformers manager constructor.
-	 *
-	 * Initializing ActivityPub transformers manager.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @access public
-	 */
-	public function __construct() {
-		$this->require_files();
-	}
-
-	/**
-	 * Require files.
-	 *
-	 * Require ActivityPub transformer base class.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @access private
-	 */
-	private function require_files() {
-		require ACTIVITYPUB_PLUGIN_DIR . 'includes/transformer/class-base.php';
-	}
-
-	/**
-	 * Checks if a transformer is registered.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 *
-	 * @param string $name Transformer name including namespace.
-	 * @return bool True if the block type is registered, false otherwise.
-	 */
-	public function is_registered( $name ) {
-		return isset( $this->transformers[ $name ] );
-	}
-
-	/**
-	 * Register a transformer.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @access public
-	 *
-	 * @param \ActivityPub\Transformer\Base $transformer_instance ActivityPub Transformer.
-	 *
-	 * @return bool True if the ActivityPub transformer was registered.
-	 */
-	public function register( \ActivityPub\Transformer\Base $transformer_instance ) {
-
-		if ( ! $transformer_instance instanceof \ActivityPub\Transformer\Base ) {
-			_doing_it_wrong(
-				__METHOD__,
-				\esc_html__( 'ActivityPub transformer instance must be a of \ActivityPub\Transformer_Base class.' ),
-				'version_number_transformer_management_placeholder'
-			);
-			return false;
-		}
-
-		$transformer_name = $transformer_instance->get_name();
-		if ( preg_match( '/[A-Z]+/', $transformer_name ) ) {
-			_doing_it_wrong(
-				__METHOD__,
-				\esc_html__( 'ActivityPub transformer names must not contain uppercase characters.' ),
-				'version_number_transformer_management_placeholder'
-			);
-			return false;
-		}
-
-		$name_matcher = '/^[a-z0-9-]+\/[a-z0-9-]+$/';
-		if ( ! preg_match( $name_matcher, $transformer_name ) ) {
-			_doing_it_wrong(
-				__METHOD__,
-				\esc_html__( 'ActivityPub transformer names must contain a namespace prefix. Example: my-plugin/my-custom-transformer' ),
-				'version_number_transformer_management_placeholder'
-			);
-			return false;
-		}
-
-		if ( $this->is_registered( $transformer_name ) ) {
-			_doing_it_wrong(
-				__METHOD__,
-				/* translators: %s: Block name. */
-				sprintf( 'ActivityPub transformer with name "%s" is already registered.', esc_html( $transformer_name ) ),
-				'version_number_transformer_management_placeholder'
-			);
-			return false;
-		}
-
-		/**
-		 * Should the ActivityPub transformer be registered.
-		 *
-		 * @since version_number_transformer_management_placeholder
-		 *
-		 * @param bool $should_register Should the ActivityPub transformer be registered. Default is `true`.
-		 * @param \ActivityPub\Transformer\Base $transformer_instance Widget instance.
-		 */
-		// TODO: does not implementing this slow down the website? -> compare with gutenberg block registration.
-		// $should_register = apply_filters( 'activitypub/transformers/is_transformer_enabled', true, $transformer_instance );
-
-		// if ( ! $should_register ) {
-		//  return false;
-		// }
-
-		$this->transformers[ $transformer_name ] = $transformer_instance;
-
-		return true;
-	}
-
-	/**
-	 * Init transformers.
-	 *
-	 * Initialize ActivityPub transformer manager.
-	 * Include the builtin transformers by default and add third party ones.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @access private
-	 */
-	private function init_transformers() {
-		$builtin_transformers = [
-			'post',
-		];
-
-		$this->transformers = [];
-
-		foreach ( $builtin_transformers as $transformer_name ) {
-			include ACTIVITYPUB_PLUGIN_DIR . 'includes/transformer/class-' . $transformer_name . '.php';
-
-			$class_name = ucfirst( $transformer_name );
-
-			$class_name = '\Activitypub\Transformer\\' . $class_name;
-
-			$this->register( new $class_name() );
-		}
-
-		/**
-		 * Let other transformers register.
-		 *
-		 * Fires after the built-in Activitypub transformers are registered.
-		 *
-		 * @since version_number_transformer_management_placeholder
-		 *
-		 * @param Transformers_Manager $this The widgets manager.
-		 */
-		do_action( 'activitypub_transformers_register', $this );
-	}
-
-	/**
-	 * Get available ActivityPub transformers.
-	 *
-	 * Retrieve the registered transformers list. If given a transformer name
-	 * it returns the given transformer if it is registered.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @access public
-	 *
-	 * @param string $transformer_name Optional. Transformer name. Default is null.
-	 *
-	 * @return Base|Base[]|null Registered transformers.
-	 */
-	public function get_transformers( $transformer_name = null ) {
-		if ( is_null( $this->transformers ) ) {
-			$this->init_transformers();
-		}
-
-		if ( null !== $transformer_name ) {
-			return isset( $this->transformers[ $transformer_name ] ) ? $this->transformers[ $transformer_name ] : null;
-		}
-
-		return $this->transformers;
-	}
-
-	/**
-	 * Get the mapped ActivityPub transformer.
-	 *
-	 * Returns a new instance of the needed WordPress to ActivityPub transformer.
-	 *
-	 * @since version_number_transformer_management_placeholder
-	 * @access public
-	 *
-	 * @param WP_Post|WP_Comment $object The WordPress Post/Comment.
-	 *
-	 * @return \ActivityPub\Transformer\Base|null Registered transformers.
-	 */
-	public function get_transformer( $object ) {
-		switch ( get_class( $object ) ) {
-			case 'WP_Post':
-				$post_type = get_post_type( $object );
-				$transformer_mapping = \get_option( 'activitypub_transformer_mapping', self::DEFAULT_TRANSFORMER_MAPPING );
-				$transformer_name = $transformer_mapping[ $post_type ];
-				$transformer_class = $this->get_transformers( $transformer_name );
-				$transformer_instance = new $transformer_class();
-				$transformer_instance->set_wp_post( $object );
-				return $transformer_instance;
-			case 'WP_Comment':
-				return new Comment( $object );
-			default:
-				return apply_filters( 'activitypub_transformer', null, $object, get_class( $object ) );
-		}
-	}
-}

integration/class-nodeinfo.php

@@ -3,6 +3,7 @@ namespace Activitypub\Integration;
 
 use function Activitypub\get_total_users;
 use function Activitypub\get_active_users;
+use function Activitypub\get_rest_url_by_path;
 
 /**
  * Compatibility with the NodeInfo plugin
@@ -14,8 +15,10 @@ class Nodeinfo {
 	 * Initialize the class, registering WordPress hooks
 	 */
 	public static function init() {
-		\add_filter( 'nodeinfo_data', array( self::class, 'add_nodeinfo_discovery' ), 10, 2 );
+		\add_filter( 'nodeinfo_data', array( self::class, 'add_nodeinfo_data' ), 10, 2 );
-		\add_filter( 'nodeinfo2_data', array( self::class, 'add_nodeinfo2_discovery' ), 10 );
+		\add_filter( 'nodeinfo2_data', array( self::class, 'add_nodeinfo2_data' ), 10 );
+
+		\add_filter( 'wellknown_nodeinfo_data', array( self::class, 'add_wellknown_nodeinfo_data' ), 10, 2 );
 	}
 
 	/**
@@ -26,7 +29,7 @@ class Nodeinfo {
 	 *
 	 * @return array The extended array
 	 */
-	public static function add_nodeinfo_discovery( $nodeinfo, $version ) {
+	public static function add_nodeinfo_data( $nodeinfo, $version ) {
 		if ( $version >= '2.0' ) {
 			$nodeinfo['protocols'][] = 'activitypub';
 		} else {
@@ -50,7 +53,7 @@ class Nodeinfo {
 	 *
 	 * @return array The extended array
 	 */
-	public static function add_nodeinfo2_discovery( $nodeinfo ) {
+	public static function add_nodeinfo2_data( $nodeinfo ) {
 		$nodeinfo['protocols'][] = 'activitypub';
 
 		$nodeinfo['usage']['users'] = array(
@@ -61,4 +64,20 @@ class Nodeinfo {
 
 		return $nodeinfo;
 	}
+
+	/**
+	 * Extend the well-known nodeinfo data
+	 *
+	 * @param array $data The well-known nodeinfo data
+	 *
+	 * @return array The extended array
+	 */
+	public static function add_wellknown_nodeinfo_data( $data ) {
+		$data['links'][] = array(
+			'rel' => 'https://www.w3.org/ns/activitystreams#Application',
+			'href' => get_rest_url_by_path( 'application' ),
+		);
+
+		return $data;
+	}
 }

integration/class-webfinger.php

@@ -14,8 +14,8 @@ class Webfinger {
 	 * Initialize the class, registering WordPress hooks
 	 */
 	public static function init() {
-		\add_filter( 'webfinger_user_data', array( self::class, 'add_user_discovery' ), 10, 3 );
+		\add_filter( 'webfinger_user_data', array( self::class, 'add_user_discovery' ), 1, 3 );
-		\add_filter( 'webfinger_data', array( self::class, 'add_pseudo_user_discovery' ), 99, 2 );
+		\add_filter( 'webfinger_data', array( self::class, 'add_pseudo_user_discovery' ), 1, 2 );
 	}
 
 	/**
@@ -34,6 +34,11 @@ class Webfinger {
 			return $array;
 		}
 
+		$array['subject'] = sprintf( 'acct:%s', $user->get_resource() );
+
+		$array['aliases'][] = $user->get_url();
+		$array['aliases'][] = $user->get_alternate_url();
+
 		$array['links'][] = array(
 			'rel'  => 'self',
 			'type' => 'application/activity+json',
@@ -53,10 +58,12 @@ class Webfinger {
 	 * @return array the jrd array
 	 */
 	public static function add_pseudo_user_discovery( $array, $resource ) {
-		if ( $array ) {
+		$user = Webfinger_Rest::get_profile( $resource );
+
+		if ( ! $user || is_wp_error( $user ) ) {
 			return $array;
 		}
 
-		return Webfinger_Rest::get_profile( $resource );
+		return $user;
 	}
 }

readme.txt

@@ -1,9 +1,9 @@
 === ActivityPub ===
 Contributors: automattic, pfefferle, mediaformat, mattwiebe, akirk, jeherve, nuriapena, cavalierlife
 Tags: OStatus, fediverse, activitypub, activitystream
-Requires at least: 4.7
+Requires at least: 5.5
 Tested up to: 6.4
-Stable tag: 1.2.0
+Stable tag: 1.3.0
 Requires PHP: 5.6
 License: MIT
 License URI: http://opensource.org/licenses/MIT
@@ -68,10 +68,10 @@ Implemented:
 * share posts
 * receive comments/reactions
 * signature verification
+* threaded comments support
 
 To implement:
 
-* threaded comments support
 * replace shortcodes with blocks for layout
 
 = What is "ActivityPub for WordPress" =
@@ -105,6 +105,27 @@ Where 'blog' is the path to the subdirectory at which your blog resides.
 
 Project maintained on GitHub at [automattic/wordpress-activitypub](https://github.com/automattic/wordpress-activitypub).
 
+= 2.0.0 =
+
+* Removed: Deprecated Classes
+* Fixed: Normalize attributes that can have mixed value types
+* Added: URL support for WebFinger
+* Added: Make Post-Template filterable
+* Added: CSS class for ActivityPub comments to allow custom designs
+* Added: FEP-2677: Identifying the Application Actor
+* Added: Basic Comment Federation
+* Added: Profile Update Activities
+* Improved: WebFinger endpoints
+
+= 1.3.0 =
+
+* Added: Threaded-Comments support
+* Improved: alt text for avatars in Follow Me/Followers blocks
+* Improved: `Delete`, `Update` and `Follow` Activities
+* Improved: better/more effective handling of `Delete` Activities
+* Improved: allow `<p />` and `<br />` for Comments
+* Fixed: removed default limit of WP_Query to send updates to all Inboxes and not only to the first 10
+
 = 1.2.0 =
 
 * Add: Search and order followerer lists

src/follow-me/follow-me.js

@@ -37,7 +37,7 @@ function Profile( { profile, popupStyles, userId } ) {
 	const { avatar, name, resource } = profile;
 	return (
 		<div className="activitypub-profile">
-			<img className="activitypub-profile__avatar" src={ avatar } />
+			<img className="activitypub-profile__avatar" src={ avatar } alt={ name } />
 			<div className="activitypub-profile__content">
 				<div className="activitypub-profile__name">{ name }</div>
 				<div className="activitypub-profile__handle" title={ resource }>{ resource }</div>

src/followers/followers.js

@@ -106,7 +106,13 @@ function Follower( { name, icon, url, preferredUsername, followLinks = true } )
 	}
 	return (
 		<ExternalLink className="activitypub-link" href={ url } title={ handle } { ...extraProps }>
-			<img width="40" height="40" src={ icon.url } class="avatar activitypub-avatar" />
+			<img
+				width="40"
+				height="40"
+				src={ icon.url }
+				class="avatar activitypub-avatar"
+				alt={ name }
+			/>
 			<span class="activitypub-actor">
 				<strong className="activitypub-name">{ name }</strong>
 				<span class="sep">/</span>

templates/admin-followers-list.php

@@ -0,0 +1,57 @@
+<?php
+
+use Activitypub\Collection\Users;
+
+\load_template(
+	__DIR__ . '/admin-header.php',
+	true,
+	array(
+		'settings' => '',
+		'welcome' => '',
+		'followers' => 'active',
+	)
+);
+
+// Draw the follow table for the blog user if it is activated.
+if ( ! \Activitypub\is_user_disabled( \Activitypub\Collection\Users::BLOG_USER_ID ) ) :
+	$table = new \Activitypub\Table\Followers();
+	$follower_count = $table->get_user_count();
+	// translators: The follower count.
+	$followers_template = _n( 'Your blog profile currently has %s follower.', 'Your blog profile currently has %s followers.', $follower_count, 'activitypub' );
+	?>
+	<div class="wrap activitypub-followers-page">
+		<p><?php \printf( \esc_html( $followers_template ), \esc_attr( $follower_count ) ); ?></p>
+	
+		<form method="get">
+			<input type="hidden" name="page" value="activitypub" />
+			<input type="hidden" name="tab" value="followers" />
+			<?php
+			$table->prepare_items();
+			$table->search_box( 'Search', 'search' );
+			$table->display();
+			?>
+			</form>
+	</div>
+	
+<?php endif;
+
+// Draw the the follow table for the application user with reject and accept options.
+$table = new \Activitypub\Table\Follow_Requests( Users::APPLICATION_USER_ID );
+$table->prepare_items();
+$follow_requests_count = $table->follow_requests_count;
+// translators: The follower count.
+$followers_template = _n( 'Your WordPress site currently has %s follow request.', 'Your WordPress site currently has %s follow requests.', $follow_requests_count, 'activitypub' );
+?>
+<div class="wrap activitypub-followers-page">
+	<p><?php \printf( \esc_html( $followers_template ), \esc_attr( $follow_requests_count ) ); ?></p>
+
+	<form method="get">
+		<input type="hidden" name="page" value="activitypub" />
+		<input type="hidden" name="tab" value="followers" />
+		<?php
+		$table->search_box( 'Search', 'search' );
+		$table->display();
+		
+		?>
+		</form>
+</div>

templates/admin-header.php

@@ -15,13 +15,10 @@
 			<?php \esc_html_e( 'Settings', 'activitypub' ); ?>
 		</a>
 
-		<?php if ( ! \Activitypub\is_user_disabled( \Activitypub\Collection\Users::BLOG_USER_ID ) ) : ?>
-
 		<a href="<?php echo \esc_url_raw( admin_url( 'options-general.php?page=activitypub&tab=followers' ) ); ?>" class="activitypub-settings-tab <?php echo \esc_attr( $args['followers'] ); ?>">
 			<?php \esc_html_e( 'Followers', 'activitypub' ); ?>
 		</a>
 
-		<?php endif; ?>
 	</nav>
 </div>
 <hr class="wp-header-end">

templates/author-json.php

@@ -10,23 +10,8 @@ $user->set_context(
  */
 \do_action( 'activitypub_json_author_pre', $user->get__id() );
 
-$options = 0;
-// JSON_PRETTY_PRINT added in PHP 5.4
-if ( \get_query_var( 'pretty' ) ) {
-	$options |= \JSON_PRETTY_PRINT; // phpcs:ignore
-}
-
-$options |= \JSON_HEX_TAG | \JSON_HEX_AMP | \JSON_HEX_QUOT;
-
-/*
- * Options to be passed to json_encode()
- *
- * @param int $options The current options flags
- */
-$options = \apply_filters( 'activitypub_json_author_options', $options, $user->get__id() );
-
 \header( 'Content-Type: application/activity+json' );
-echo \wp_json_encode( $user->to_array(), $options );
+echo $user->to_json(); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
 
 /*
  * Action triggerd after the ActivityPub profile has been created and sent to the client

templates/blog-json.php

@@ -10,23 +10,8 @@ $user->set_context(
  */
 \do_action( 'activitypub_json_author_pre', $user->get__id() );
 
-$options = 0;
-// JSON_PRETTY_PRINT added in PHP 5.4
-if ( \get_query_var( 'pretty' ) ) {
-	$options |= \JSON_PRETTY_PRINT; // phpcs:ignore
-}
-
-$options |= \JSON_HEX_TAG | \JSON_HEX_AMP | \JSON_HEX_QUOT;
-
-/*
- * Options to be passed to json_encode()
- *
- * @param int $options The current options flags
- */
-$options = \apply_filters( 'activitypub_json_author_options', $options, $user->get__id() );
-
 \header( 'Content-Type: application/activity+json' );
-echo \wp_json_encode( $user->to_array(), $options );
+echo $user->to_json(); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
 
 /*
  * Action triggerd after the ActivityPub profile has been created and sent to the client

templates/blog-user-followers-list.php

@@ -1,28 +0,0 @@
-<?php
-\load_template(
-	__DIR__ . '/admin-header.php',
-	true,
-	array(
-		'settings' => '',
-		'welcome' => '',
-		'followers' => 'active',
-	)
-);
-$table = new \Activitypub\Table\Followers();
-$follower_count = $table->get_user_count();
-// translators: The follower count.
-$followers_template = _n( 'Your blog profile currently has %s follower.', 'Your blog profile currently has %s followers.', $follower_count, 'activitypub' );
-?>
-<div class="wrap activitypub-followers-page">
-	<p><?php \printf( \esc_html( $followers_template ), \esc_attr( $follower_count ) ); ?></p>
-
-	<form method="get">
-		<input type="hidden" name="page" value="activitypub" />
-		<input type="hidden" name="tab" value="followers" />
-		<?php
-		$table->prepare_items();
-		$table->search_box( 'Search', 'search' );
-		$table->display();
-		?>
-		</form>
-</div>

templates/comment-json.php

@@ -0,0 +1,36 @@
+<?php
+$comment = \get_comment( \get_query_var( 'c', null ) ); // phpcs:ignore
+
+$object = \Activitypub\Transformer\Factory::get_transformer( $comment );
+$json = \array_merge( array( '@context' => \Activitypub\get_context() ), $object->to_object()->to_array() );
+
+// filter output
+$json = \apply_filters( 'activitypub_json_comment_array', $json );
+
+/*
+ * Action triggerd prior to the ActivityPub profile being created and sent to the client
+ */
+\do_action( 'activitypub_json_comment_pre' );
+
+$options = 0;
+// JSON_PRETTY_PRINT added in PHP 5.4
+if ( \get_query_var( 'pretty' ) ) {
+	$options |= \JSON_PRETTY_PRINT; // phpcs:ignore
+}
+
+$options |= \JSON_HEX_TAG | \JSON_HEX_AMP | \JSON_HEX_QUOT;
+
+/*
+ * Options to be passed to json_encode()
+ *
+ * @param int $options The current options flags
+ */
+$options = \apply_filters( 'activitypub_json_comment_options', $options );
+
+\header( 'Content-Type: application/activity+json' );
+echo \wp_json_encode( $json, $options );
+
+/*
+ * Action triggerd after the ActivityPub profile has been created and sent to the client
+ */
+\do_action( 'activitypub_json_comment_comment' );

templates/post-json.php

@@ -2,35 +2,16 @@
 // phpcs:ignore WordPress.WP.GlobalVariablesOverride.Prohibited
 $post = \get_post();
 
-$transformer = \Activitypub\Transformer\Transformers_Manager::instance()->get_transformer( $post );
+$post_object = \Activitypub\Transformer\Factory::get_transformer( $post )->to_object();
-
+$post_object->set_context( \Activitypub\get_context() );
-$json = \array_merge( array( '@context' => \Activitypub\get_context() ), $transformer->to_object()->to_array() );
-
-// filter output
-$json = \apply_filters( 'activitypub_json_post_array', $json );
 
 /*
  * Action triggerd prior to the ActivityPub profile being created and sent to the client
  */
 \do_action( 'activitypub_json_post_pre' );
 
-$options = 0;
-// JSON_PRETTY_PRINT added in PHP 5.4
-if ( \get_query_var( 'pretty' ) ) {
-	$options |= \JSON_PRETTY_PRINT; // phpcs:ignore
-}
-
-$options |= \JSON_HEX_TAG | \JSON_HEX_AMP | \JSON_HEX_QUOT;
-
-/*
- * Options to be passed to json_encode()
- *
- * @param int $options The current options flags
- */
-$options = \apply_filters( 'activitypub_json_post_options', $options );
-
 \header( 'Content-Type: application/activity+json' );
-echo \wp_json_encode( $json, $options );
+echo $post_object->to_json(); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
 
 /*
  * Action triggerd after the ActivityPub profile has been created and sent to the client

templates/settings.php

@@ -93,7 +93,7 @@
 									<?php \esc_html_e( 'Excerpt', 'activitypub' ); ?>
 									-
 									<span class="description">
-										<?php \esc_html_e( 'A content summary, shortened to 400 characters and without markup.', 'activitypub' ); ?>
+										<?php \esc_html_e( 'A content summary without markup (truncated if no excerpt is provided).', 'activitypub' ); ?>
 									</span>
 								</label>
 							</p>
@@ -125,7 +125,7 @@
 										<ul>
 											<li><code>[ap_title]</code> - <?php \esc_html_e( 'The post\'s title.', 'activitypub' ); ?></li>
 											<li><code>[ap_content]</code> - <?php \esc_html_e( 'The post\'s content.', 'activitypub' ); ?></li>
-											<li><code>[ap_excerpt]</code> - <?php \esc_html_e( 'The post\'s excerpt (default 400 chars).', 'activitypub' ); ?></li>
+											<li><code>[ap_excerpt]</code> - <?php \esc_html_e( 'The post\'s excerpt (may be truncated).', 'activitypub' ); ?></li>
 											<li><code>[ap_permalink]</code> - <?php \esc_html_e( 'The post\'s permalink.', 'activitypub' ); ?></li>
 											<li><code>[ap_shortlink]</code> - <?php echo \wp_kses( \__( 'The post\'s shortlink. I can recommend <a href="https://wordpress.org/plugins/hum/" target="_blank">Hum</a>.', 'activitypub' ), 'default' ); ?></li>
 											<li><code>[ap_hashtags]</code> - <?php \esc_html_e( 'The post\'s tags as hashtags.', 'activitypub' ); ?></li>
@@ -201,6 +201,26 @@
 							</p>
 						</td>
 					</tr>
+					<tr>
+						<th scope="row"><?php \esc_html_e( 'Supported post types', 'activitypub' ); ?></th>
+						<td>
+							<fieldset>
+								<?php \esc_html_e( 'Enable ActivityPub support for the following post types:', 'activitypub' ); ?>
+
+								<?php $post_types = \get_post_types( array( 'public' => true ), 'objects' ); ?>
+								<?php $support_post_types = \get_option( 'activitypub_support_post_types', array( 'post', 'page' ) ) ? \get_option( 'activitypub_support_post_types', array( 'post', 'page' ) ) : array(); ?>
+								<ul>
+								<?php // phpcs:ignore WordPress.WP.GlobalVariablesOverride.Prohibited ?>
+								<?php foreach ( $post_types as $post_type ) { ?>
+									<li>
+										<input type="checkbox" id="activitypub_support_post_type_<?php echo \esc_attr( $post_type->name ); ?>" name="activitypub_support_post_types[]" value="<?php echo \esc_attr( $post_type->name ); ?>" <?php echo \checked( \in_array( $post_type->name, $support_post_types, true ) ); ?> />
+										<label for="activitypub_support_post_type_<?php echo \esc_attr( $post_type->name ); ?>"><?php echo \esc_html( $post_type->label ); ?></label>
+									</li>
+								<?php } ?>
+								</ul>
+							</fieldset>
+						</td>
+					</tr>
 					<tr>
 						<th scope="row">
 							<?php \esc_html_e( 'Hashtags (beta)', 'activitypub' ); ?>
@@ -217,93 +237,6 @@
 			<?php \do_settings_fields( 'activitypub', 'activity' ); ?>
 		</div>
 
-		<!-- OUR FORK HERE -->
-		<div class="box">
-		<h3><?php \esc_html_e( 'Enable ActivityPub support for post type', 'activitypub' ); ?></h3>
-
-		<table class="form-table">
-				<tbody>
-					<tr>
-						<th scope="row">
-							<?php \esc_html_e( 'Mapping', 'activitypub' ); ?>
-						</th>
-						<td>
-						<?php \esc_html_e( 'Enable ActivityPub support for a certain post type by selecting one of the available ActivityPub transformers.', 'activitypub' ); ?>
-
-				<?php $all_public_post_types = \get_post_types( array( 'public' => true ), 'objects' );
-				$transformer_mapping =  \get_option( 'activitypub_transformer_mapping', array( 'default' => 'note' ) );
-
-				$all_public_post_type_names = array_map(function ($object) {
-					return $object->name;
-				}, $all_public_post_types);
-
-				$transformer_manager = \Activitypub\Transformer\Transformers_Manager::instance();
-				$transformers = $transformer_manager->get_transformers();
-
-				?>
-
-
-				<script>
-					// TODO Probably we should use checkboxes and not select and make this less buggy and insert the js at the right place.
-					document.addEventListener('DOMContentLoaded', function () {
-						var radioGroups = {};
-
-						var radioButtons = document.querySelectorAll('input[type="radio"]');
-
-						radioButtons.forEach(function (radioButton) {
-							radioButton.addEventListener('click', function () {
-								var name = this.name;
-
-								if (!radioGroups[name]) {
-									radioGroups[name] = this;
-								} else {
-									radioGroups[name].checked = false;
-									radioGroups[name] = this;
-								}
-							});
-						});
-					});
-				</script>
-
-				<table>
-					<thead>
-					<tr>
-						<th></th>
-						<?php
-						// Generate column headers based on transformer objects
-						foreach ($transformers as $transformer) {
-							echo '<th>' . htmlspecialchars($transformer->get_label()) . '</th>';
-						}
-						?>
-					</tr>
-					</thead>
-					<tbody>
-					<?php
-					// Generate rows based on post types and transformers
-					foreach ($all_public_post_types as $post_type) {
-						echo '<tr>';
-						echo '<td><strong>' . htmlspecialchars($post_type->label) . '</strong></td>';
-						// Generate radio inputs for each transformer, considering support for the post type
-						foreach ($transformers as $transformer) {
-							$disabled_attribute = $transformer->supports_post_type( $post_type->name ) ? '' : ' disabled';
-							$is_selected = ( is_array( $transformer_mapping ) && isset( $transformer_mapping[ $post_type->name ] ) && $transformer_mapping[ $post_type->name ] === $transformer->get_name() ) ? ' checked ' : '';
-							echo '<td><input type="radio" name="activitypub_transformer_mapping[' . $post_type->name . ']" value="' . $transformer->get_name() . '"' . $is_selected . $disabled_attribute . '></td>';
-						}
-
-						echo '</tr>';
-					}
-					?>
-					</tbody>
-				</table>
-
-
-				</td>
-			</tr>
-				</tbody>
-				</table>
-		</div>
-		<!-- OUR FORK ENDS HERE -->
-
 		<div class="box">
 			<h3><?php \esc_html_e( 'Server', 'activitypub' ); ?></h3>
 			<table class="form-table">

tests/class-activitypub-testcase-cache-http.php

@@ -12,7 +12,7 @@ class ActivityPub_TestCase_Cache_HTTP extends \WP_UnitTestCase {
 
 		add_filter(
 			'rest_url',
-			function() {
+			function () {
 				return get_option( 'home' ) . '/wp-json/';
 			}
 		);

tests/test-class-activitypub-activity-dispatcher.php

@@ -70,7 +70,7 @@ class Test_Activitypub_Activity_Dispatcher extends ActivityPub_TestCase_Cache_HT
 
 		add_filter(
 			'activitypub_extract_mentions',
-			function( $mentions ) {
+			function ( $mentions ) {
 				$mentions[] = 'https://example.com/alex';
 				return $mentions;
 			},
@@ -134,7 +134,7 @@ class Test_Activitypub_Activity_Dispatcher extends ActivityPub_TestCase_Cache_HT
 
 		add_filter(
 			'activitypub_is_user_type_disabled',
-			function( $value, $type ) {
+			function ( $value, $type ) {
 				if ( 'blog' === $type ) {
 					return false;
 				} else {

tests/test-class-activitypub-activity.php

@@ -1,4 +1,6 @@
 <?php
+use DMS\PHPUnitExtensions\ArraySubset\Assert;
+
 class Test_Activitypub_Activity extends WP_UnitTestCase {
 	public function test_activity_mentions() {
 		$post = \wp_insert_post(
@@ -10,15 +12,14 @@ class Test_Activitypub_Activity extends WP_UnitTestCase {
 
 		add_filter(
 			'activitypub_extract_mentions',
-			function( $mentions ) {
+			function ( $mentions ) {
 				$mentions['@alex'] = 'https://example.com/alex';
 				return $mentions;
 			},
 			10
 		);
 
-		$wp_post = get_post( $post );
+		$activitypub_post = \Activitypub\Transformer\Post::transform( get_post( $post ) )->to_object();
-		$activitypub_post = \Activitypub\Transformer\Transformers_Manager::instance()->get_transformer( $post )->to_object();
 
 		$activitypub_activity = new \Activitypub\Activity\Activity();
 		$activitypub_activity->set_type( 'Create' );
@@ -43,4 +44,21 @@ class Test_Activitypub_Activity extends WP_UnitTestCase {
 		$this->assertEquals( 'Hello world!', $object->get_content() );
 		$this->assertEquals( $test_array, $object->to_array() );
 	}
+
+	public function test_activity_object() {
+		$test_array = array(
+			'id'      => 'https://example.com/post/123',
+			'type'    => 'Create',
+			'object'  => array(
+				'id'      => 'https://example.com/post/123/activity',
+				'type'    => 'Note',
+				'content' => 'Hello world!',
+			),
+		);
+
+		$activity = \Activitypub\Activity\Activity::init_from_array( $test_array );
+
+		$this->assertEquals( 'Hello world!', $activity->get_object()->get_content() );
+		Assert::assertArraySubset( $test_array, $activity->to_array() );
+	}
 }

tests/test-class-activitypub-create-handler.php

@@ -0,0 +1,70 @@
+<?php
+class Test_Activitypub_Create_Handler extends WP_UnitTestCase {
+	public $user_id;
+	public $user_url;
+	public $post_id;
+	public $post_permalink;
+
+	public function set_up() {
+		$this->user_id = 1;
+		$authordata = \get_userdata( $this->user_id );
+		$this->user_url = $authordata->user_url;
+
+		$this->post_id = \wp_insert_post(
+			array(
+				'post_author' => $this->user_id,
+				'post_content' => 'test',
+			)
+		);
+		$this->post_permalink = \get_permalink( $this->post_id );
+
+		\add_filter( 'pre_get_remote_metadata_by_actor', array( '\Test_Activitypub_Create_Handler', 'get_remote_metadata_by_actor' ), 0, 2 );
+	}
+
+	public static function get_remote_metadata_by_actor( $value, $actor ) {
+		return array(
+			'name' => 'Example User',
+			'icon' => array(
+				'url' => 'https://example.com/icon',
+			),
+			'url'  => $actor,
+			'id'   => 'http://example.org/users/example',
+		);
+	}
+
+	public function create_test_object( $id = 'https://example.com/123' ) {
+		return array(
+			'actor' => $this->user_url,
+			'id' => 'https://example.com/id/' . microtime( true ),
+			'to' => [ $this->user_url ],
+			'cc' => [ 'https://www.w3.org/ns/activitystreams#Public' ],
+			'object' => array(
+				'id'        => $id,
+				'url'       => 'https://example.com/example',
+				'inReplyTo' => $this->post_permalink,
+				'content'   => 'example',
+			),
+		);
+	}
+
+	public function test_handle_create_object_unset_rejected() {
+		$object = $this->create_test_object();
+		unset( $object['object'] );
+		$converted = Activitypub\Handler\Create::handle_create( $object, $this->user_id );
+		$this->assertNull( $converted );
+	}
+
+	public function test_handle_create_non_public_rejected() {
+		$object = $this->create_test_object();
+		$object['cc'] = [];
+		$converted = Activitypub\Handler\Create::handle_create( $object, $this->user_id );
+		$this->assertNull( $converted );
+	}
+
+	public function test_handle_create_no_id_rejected() {
+		$object = $this->create_test_object();
+		unset( $object['object']['id'] );
+		$converted = Activitypub\Handler\Create::handle_create( $object, $this->user_id );
+		$this->assertNull( $converted );
+	}
+}

tests/test-class-activitypub-followers.php

@@ -1,5 +1,5 @@
 <?php
-class Test_Db_Activitypub_Followers extends WP_UnitTestCase {
+class Test_Activitypub_Followers extends WP_UnitTestCase {
 	public static $users = array(
 		'username@example.org' => array(
 			'id' => 'https://example.org/users/username',
@@ -76,7 +76,7 @@ class Test_Db_Activitypub_Followers extends WP_UnitTestCase {
 		$this->assertEquals( 3, \count( $db_followers ) );
 
 		$db_followers = array_map(
-			function( $item ) {
+			function ( $item ) {
 				return $item->get_url();
 			},
 			$db_followers
@@ -329,6 +329,82 @@ class Test_Db_Activitypub_Followers extends WP_UnitTestCase {
 		$this->assertEquals( $name, $follower->get_name() );
 	}
 
+	public function test_get_inboxes() {
+		for ( $i = 0; $i < 30; $i++ ) {
+			$meta = array(
+				'id' => 'https://example.org/users/' . $i,
+				'url' => 'https://example.org/users/' . $i,
+				'inbox' => 'https://example.org/users/' . $i . '/inbox',
+				'name'  => 'user' . $i,
+				'preferredUsername'  => 'user' . $i,
+				'publicKey' => 'https://example.org/users/' . $i . '#main-key',
+				'publicKeyPem' => $i,
+			);
+
+			$follower = new \Activitypub\Model\Follower();
+			$follower->from_array( $meta );
+
+			$id = $follower->upsert();
+
+			add_post_meta( $id, 'activitypub_user_id', 1 );
+		}
+
+		$inboxes = \Activitypub\Collection\Followers::get_inboxes( 1 );
+
+		$this->assertCount( 30, $inboxes );
+
+		wp_cache_delete( sprintf( \Activitypub\Collection\Followers::CACHE_KEY_INBOXES, 1 ), 'activitypub' );
+
+		for ( $j = 0; $j < 5; $j++ ) {
+			$k = $j + 100;
+			$meta = array(
+				'id' => 'https://example.org/users/' . $k,
+				'url' => 'https://example.org/users/' . $k,
+				'inbox' => 'https://example.org/users/' . $j . '/inbox',
+				'name'  => 'user' . $k,
+				'preferredUsername'  => 'user' . $k,
+				'publicKey' => 'https://example.org/users/' . $k . '#main-key',
+				'publicKeyPem' => $k,
+			);
+
+			$follower = new \Activitypub\Model\Follower();
+			$follower->from_array( $meta );
+
+			$id = $follower->upsert();
+
+			add_post_meta( $id, 'activitypub_user_id', 1 );
+		}
+
+		$inboxes2 = \Activitypub\Collection\Followers::get_inboxes( 1 );
+
+		$this->assertCount( 30, $inboxes2 );
+	}
+
+	public function test_get_all_followers() {
+		for ( $i = 0; $i < 30; $i++ ) {
+			$meta = array(
+				'id' => 'https://example.org/users/' . $i,
+				'url' => 'https://example.org/users/' . $i,
+				'inbox' => 'https://example.org/users/' . $i . '/inbox',
+				'name'  => 'user' . $i,
+				'preferredUsername'  => 'user' . $i,
+				'publicKey' => 'https://example.org/users/' . $i . '#main-key',
+				'publicKeyPem' => $i,
+			);
+
+			$follower = new \Activitypub\Model\Follower();
+			$follower->from_array( $meta );
+
+			$id = $follower->upsert();
+
+			add_post_meta( $id, 'activitypub_user_id', 1 );
+		}
+
+		$followers = \Activitypub\Collection\Followers::get_all_followers();
+
+		$this->assertCount( 30, $followers );
+	}
+
 	public static function http_request_host_is_external( $in, $host ) {
 		if ( in_array( $host, array( 'example.com', 'example.org' ), true ) ) {
 			return true;

tests/test-class-activitypub-interactions.php

@@ -0,0 +1,174 @@
+<?php
+class Test_Activitypub_Interactions extends WP_UnitTestCase {
+	public $user_id;
+	public $user_url;
+	public $post_id;
+	public $post_permalink;
+
+	public function set_up() {
+		$this->user_id = 1;
+		$authordata = \get_userdata( $this->user_id );
+		$this->user_url = $authordata->user_url;
+
+		$this->post_id = \wp_insert_post(
+			array(
+				'post_author' => $this->user_id,
+				'post_content' => 'test',
+			)
+		);
+		$this->post_permalink = \get_permalink( $this->post_id );
+
+		\add_filter( 'pre_get_remote_metadata_by_actor', array( '\Test_Activitypub_Interactions', 'get_remote_metadata_by_actor' ), 0, 2 );
+	}
+
+	public static function get_remote_metadata_by_actor( $value, $actor ) {
+		return array(
+			'name' => 'Example User',
+			'icon' => array(
+				'url' => 'https://example.com/icon',
+			),
+			'url'  => $actor,
+			'id'   => 'http://example.org/users/example',
+		);
+	}
+
+	public function create_test_object( $id = 'https://example.com/123' ) {
+		return array(
+			'actor' => $this->user_url,
+			'id' => 'https://example.com/id/' . microtime( true ),
+			'to' => [ $this->user_url ],
+			'cc' => [ 'https://www.w3.org/ns/activitystreams#Public' ],
+			'object' => array(
+				'id'        => $id,
+				'url'       => 'https://example.com/example',
+				'inReplyTo' => $this->post_permalink,
+				'content'   => 'example',
+			),
+		);
+	}
+
+	public function create_test_rich_object( $id = 'https://example.com/123' ) {
+		return array(
+			'actor' => $this->user_url,
+			'id' => 'https://example.com/id/' . microtime( true ),
+			'to' => [ $this->user_url ],
+			'cc' => [ 'https://www.w3.org/ns/activitystreams#Public' ],
+			'object' => array(
+				'id'        => $id,
+				'url'       => 'https://example.com/example',
+				'inReplyTo' => $this->post_permalink,
+				'content'   => 'Hello<br />example<p>example</p><img src="https://example.com/image.jpg" />',
+			),
+		);
+	}
+
+	public function test_handle_create_basic() {
+		$comment_id = Activitypub\Collection\Interactions::add_comment( $this->create_test_object() );
+		$comment   = get_comment( $comment_id, ARRAY_A );
+
+		$this->assertIsArray( $comment );
+		$this->assertEquals( $this->post_id, $comment['comment_post_ID'] );
+		$this->assertEquals( 'Example User', $comment['comment_author'] );
+		$this->assertEquals( $this->user_url, $comment['comment_author_url'] );
+		$this->assertEquals( 'example', $comment['comment_content'] );
+		$this->assertEquals( 'comment', $comment['comment_type'] );
+		$this->assertEquals( '', $comment['comment_author_email'] );
+		$this->assertEquals( 0, $comment['comment_parent'] );
+		$this->assertEquals( 'https://example.com/123', get_comment_meta( $comment_id, 'source_id', true ) );
+		$this->assertEquals( 'https://example.com/example', get_comment_meta( $comment_id, 'source_url', true ) );
+		$this->assertEquals( 'https://example.com/icon', get_comment_meta( $comment_id, 'avatar_url', true ) );
+		$this->assertEquals( 'activitypub', get_comment_meta( $comment_id, 'protocol', true ) );
+	}
+
+	public function test_handle_create_rich() {
+		$comment_id = Activitypub\Collection\Interactions::add_comment( $this->create_test_rich_object() );
+		$comment    = get_comment( $comment_id, ARRAY_A );
+
+		$this->assertEquals( 'Hello<br />example<p>example</p>', $comment['comment_content'] );
+
+		$commentarray = array(
+			'comment_post_ID'      => $this->post_id,
+			'comment_author'       => 'Example User',
+			'comment_author_url'   => $this->user_url,
+			'comment_content'      => 'Hello<br />example<p>example</p>',
+			'comment_type'         => 'comment',
+			'comment_author_email' => '',
+			'comment_parent'       => 0,
+			'comment_meta'         => array(
+				'source_id'  => 'https://example.com/123',
+				'source_url' => 'https://example.com/example',
+				'protocol'   => 'activitypub',
+			),
+		);
+
+		\remove_action( 'check_comment_flood', 'check_comment_flood_db', 10 );
+		$comment_id = wp_new_comment( $commentarray );
+		\add_action( 'check_comment_flood', 'check_comment_flood_db', 10, 4 );
+		$comment = get_comment( $comment_id, ARRAY_A );
+
+		$this->assertEquals( 'Helloexampleexample', $comment['comment_content'] );
+	}
+
+	public function test_convert_object_to_comment_not_reply_rejected() {
+		$object = $this->create_test_object();
+		unset( $object['object']['inReplyTo'] );
+		$converted = Activitypub\Collection\Interactions::add_comment( $object );
+		$this->assertFalse( $converted );
+	}
+
+	public function test_convert_object_to_comment_already_exists_rejected() {
+		$object = $this->create_test_object( 'https://example.com/test_convert_object_to_comment_already_exists_rejected' );
+		Activitypub\Collection\Interactions::add_comment( $object );
+		$converted = Activitypub\Collection\Interactions::add_comment( $object );
+		$this->assertEquals( $converted->get_error_code(), 'comment_duplicate' );
+	}
+
+	public function test_convert_object_to_comment_reply_to_comment() {
+		$id = 'https://example.com/test_convert_object_to_comment_reply_to_comment';
+		$object = $this->create_test_object( $id );
+		Activitypub\Collection\Interactions::add_comment( $object );
+		$comment = \Activitypub\object_id_to_comment( $id );
+
+		$object['object']['inReplyTo'] = $id;
+		$object['object']['id'] = 'https://example.com/234';
+		$id = Activitypub\Collection\Interactions::add_comment( $object );
+		$converted = get_comment( $id, ARRAY_A );
+
+		$this->assertIsArray( $converted );
+		$this->assertEquals( $this->post_id, $converted['comment_post_ID'] );
+		$this->assertEquals( $comment->comment_ID, $converted['comment_parent'] );
+	}
+
+	public function test_convert_object_to_comment_reply_to_non_existent_comment_rejected() {
+		$object = $this->create_test_object();
+		$object['object']['inReplyTo'] = 'https://example.com/not_found';
+		$converted = Activitypub\Collection\Interactions::add_comment( $object );
+		$this->assertFalse( $converted );
+	}
+
+	public function test_handle_create_basic2() {
+		$id = 'https://example.com/test_handle_create_basic';
+		$object = $this->create_test_object( $id );
+		Activitypub\Collection\Interactions::add_comment( $object );
+		$comment = \Activitypub\object_id_to_comment( $id );
+		$this->assertInstanceOf( WP_Comment::class, $comment );
+	}
+
+	public function test_get_interaction_by_id() {
+		$id = 'https://example.com/test_get_interaction_by_id';
+		$url = 'https://example.com/test_get_interaction_by_url';
+		$object = $this->create_test_object( $id );
+		$object['object']['url'] = $url;
+
+		Activitypub\Collection\Interactions::add_comment( $object );
+		$comment = \Activitypub\object_id_to_comment( $id );
+		$interactions = Activitypub\Collection\Interactions::get_interaction_by_id( $id );
+		$this->assertIsArray( $interactions );
+		$this->assertEquals( $comment->comment_ID, $interactions[0]->comment_ID );
+
+		$comment = \Activitypub\object_id_to_comment( $id );
+		$interactions = Activitypub\Collection\Interactions::get_interaction_by_id( $url );
+		$this->assertIsArray( $interactions );
+		$this->assertEquals( $comment->comment_ID, $interactions[0]->comment_ID );
+	}
+}

tests/test-class-activitypub-post.php

@@ -10,13 +10,13 @@ class Test_Activitypub_Post extends WP_UnitTestCase {
 
 		$permalink = \get_permalink( $post );
 
-		$activitypub_post = \Activitypub\Transformer\Transformers_Manager::instance()->get_transformer( get_post( $post ) )->to_object();
+		$activitypub_post = \Activitypub\Transformer\Post::transform( get_post( $post ) )->to_object();
 
 		$this->assertEquals( $permalink, $activitypub_post->get_id() );
 
 		\wp_trash_post( $post );
 
-		$activitypub_post = \Activitypub\Transformer\Transformers_Manager::instance()->get_transformer( get_post( $post ) )->to_object();
+		$activitypub_post = \Activitypub\Transformer\Post::transform( get_post( $post ) )->to_object();
 
 		$this->assertEquals( $permalink, $activitypub_post->get_id() );
 

tests/test-class-activitypub-rest-inbox.php

@@ -5,7 +5,7 @@ class Test_Activitypub_Rest_Inbox extends WP_UnitTestCase {
 	 */
 	public function test_is_activity_public( $data, $check ) {
 
-		$this->assertEquals( $check, Activitypub\Rest\Inbox::is_activity_public( $data ) );
+		$this->assertEquals( $check, Activitypub\is_activity_public( $data ) );
 	}
 
 	public function the_data_provider() {

tests/test-class-activitypub-rest-post-signature-verification.php

@@ -10,7 +10,7 @@ class Test_Activitypub_Signature_Verification extends WP_UnitTestCase {
 			)
 		);
 		$remote_actor = \get_author_posts_url( 2 );
-		$activitypub_post = \Activitypub\Transformer\Transformers_Manager::instance()->get_transformer( get_post( $post ) )->to_object();
+		$activitypub_post = \Activitypub\Transformer\Post::transform( get_post( $post ) )->to_object();
 		$activitypub_activity = new Activitypub\Activity\Activity( 'Create' );
 		$activitypub_activity->set_type( 'Create' );
 		$activitypub_activity->set_object( $activitypub_post );
@@ -55,7 +55,7 @@ class Test_Activitypub_Signature_Verification extends WP_UnitTestCase {
 	public function test_rest_activity_signature() {
 		add_filter(
 			'pre_get_remote_metadata_by_actor',
-			function( $json, $actor ) {
+			function ( $json, $actor ) {
 				$user = Activitypub\Collection\Users::get_by_id( 1 );
 				$public_key = Activitypub\Signature::get_public_key_for( $user->get__id() );
 				// return ActivityPub Profile with signature
@@ -82,7 +82,7 @@ class Test_Activitypub_Signature_Verification extends WP_UnitTestCase {
 		);
 		$remote_actor = \get_author_posts_url( 2 );
 		$remote_actor_inbox = Activitypub\get_rest_url_by_path( '/inbox' );
-		$activitypub_post = \Activitypub\Transformer\Transformers_Manager::instance()->get_transformer( get_post( $post )  )->to_object();
+		$activitypub_post = \Activitypub\Transformer\Post::transform( \get_post( $post ) )->to_object();
 		$activitypub_activity = new Activitypub\Activity\Activity();
 		$activitypub_activity->set_type( 'Create' );
 		$activitypub_activity->set_object( $activitypub_post );

tests/test-class-activitypub-shortcodes.php

@@ -62,4 +62,34 @@ class Test_Activitypub_Shortcodes extends WP_UnitTestCase {
 		$this->assertEquals( '', $content );
 		Shortcodes::unregister();
 	}
+
+	public function test_excerpt() {
+		Shortcodes::register();
+		global $post;
+
+		$post_id = -97; // negative ID, to avoid clash with a valid post
+		$post = new stdClass();
+		$post->ID = $post_id;
+		$post->post_author = 1;
+		$post->post_date = current_time( 'mysql' );
+		$post->post_date_gmt = current_time( 'mysql', 1 );
+		$post->post_title = 'Some title or other';
+		$post->post_content = '<script>test</script>Lorem ipsum dolor sit amet, consectetur.<script type="javascript">{"asdf": "qwerty"}</script><style></style>';
+		$post->post_status = 'publish';
+		$post->comment_status = 'closed';
+		$post->ping_status = 'closed';
+		$post->post_name = 'fake-page-' . rand( 1, 99999 ); // append random number to avoid clash
+		$post->post_type = 'page';
+		$post->filter = 'raw'; // important!
+
+		$content = '[ap_excerpt length="25"]';
+
+		// Fill in the shortcodes.
+		setup_postdata( $post );
+		$content = do_shortcode( $content );
+		wp_reset_postdata();
+
+		$this->assertEquals( "<p>Lorem ipsum [&hellip;]</p>\n", $content );
+		Shortcodes::unregister();
+	}
 }

tests/test-class-activitypub-users-collection.php

@@ -0,0 +1,43 @@
+<?php
+class Test_Activitypub_Users_Collection extends WP_UnitTestCase {
+
+	public function set_up() {
+		parent::set_up();
+
+		add_option( 'activitypub_blog_user_identifier', 'blog' );
+		add_user_meta( 1, 'activitypub_user_identifier', 'admin' );
+	}
+	/**
+	 * @dataProvider the_resource_provider
+	 */
+	public function test_get_by_various( $resource, $expected ) {
+		$user = Activitypub\Collection\Users::get_by_resource( $resource );
+
+		$this->assertInstanceOf( $expected, $user );
+	}
+
+	public function the_resource_provider() {
+		return array(
+			array( 'http://example.org/?author=1', 'Activitypub\Model\User' ),
+			array( 'https://example.org/?author=1', 'Activitypub\Model\User' ),
+			array( 'http://example.org/?author=7', 'WP_Error' ),
+			array( 'acct:admin@example.org', 'Activitypub\Model\User' ),
+			array( 'acct:blog@example.org', 'Activitypub\Model\Blog_User' ),
+			array( 'acct:*@example.org', 'Activitypub\Model\Blog_User' ),
+			array( 'acct:_@example.org', 'Activitypub\Model\Blog_User' ),
+			array( 'acct:aksd@example.org', 'WP_Error' ),
+			array( 'admin@example.org', 'Activitypub\Model\User' ),
+			array( 'acct:application@example.org', 'Activitypub\Model\Application_User' ),
+			array( 'http://example.org/@admin', 'Activitypub\Model\User' ),
+			array( 'http://example.org/@blog', 'Activitypub\Model\Blog_User' ),
+			array( 'https://example.org/@blog', 'Activitypub\Model\Blog_User' ),
+			array( 'http://example.org/@blog/', 'Activitypub\Model\Blog_User' ),
+			array( 'http://example.org/', 'Activitypub\Model\Blog_User' ),
+			array( 'http://example.org', 'Activitypub\Model\Blog_User' ),
+			array( 'https://example.org/', 'Activitypub\Model\Blog_User' ),
+			array( 'https://example.org', 'Activitypub\Model\Blog_User' ),
+			array( 'http://example.org/@blog/s', 'WP_Error' ),
+			array( 'http://example.org/@blogs/', 'WP_Error' ),
+		);
+	}
+}

tests/test-class-activitypub-webfinger.php

@@ -0,0 +1,21 @@
+<?php
+class Test_Activitypub_Webfinger extends WP_UnitTestCase {
+	/**
+	 * @dataProvider the_cache_key_provider
+	 */
+	public function test_generate_cache_key( $uri, $hash ) {
+		$cache_key = Activitypub\Webfinger::generate_cache_key( $uri );
+
+		$this->assertEquals( $cache_key, 'webfinger_' . $hash );
+	}
+
+	public function the_cache_key_provider() {
+		return array(
+			array( 'http://example.org/?author=1', md5( 'http://example.org/?author=1' ) ),
+			array( '@author@example.org', md5( 'acct:author@example.org' ) ),
+			array( 'author@example.org', md5( 'acct:author@example.org' ) ),
+			array( 'acct:author@example.org', md5( 'acct:author@example.org' ) ),
+			array( 'https://example.org', md5( 'https://example.org' ) ),
+		);
+	}
+}

tests/test-class-admin.php

@@ -0,0 +1,18 @@
+<?php
+class Test_Admin extends WP_UnitTestCase {
+	public function test_no_permalink_structure_has_errors() {
+		\add_option( 'permalink_structure', '' );
+		\do_action( 'admin_notices' );
+		$this->expectOutputRegex( "/notice-error/" );
+
+		\delete_option( 'permalink_structure' );
+	}
+
+	public function test_has_permalink_structure_no_errors() {
+		\add_option( 'permalink_structure', '/archives/%post_id%' );
+		\do_action( 'admin_notices' );
+		$this->expectOutputRegex( "/^((?!notice-error).)*$/s" );
+
+		\delete_option( 'permalink_structure' );
+	}
+}

tests/test-functions.php

@@ -1,9 +1,149 @@
 <?php
 class Test_Functions extends ActivityPub_TestCase_Cache_HTTP {
+	public $user_id;
+	public $post_id;
+
 	public function test_get_remote_metadata_by_actor() {
 		$metadata = \ActivityPub\get_remote_metadata_by_actor( 'pfefferle@notiz.blog' );
 		$this->assertEquals( 'https://notiz.blog/author/matthias-pfefferle/', $metadata['url'] );
 		$this->assertEquals( 'pfefferle', $metadata['preferredUsername'] );
 		$this->assertEquals( 'Matthias Pfefferle', $metadata['name'] );
 	}
+
+	public function set_up() {
+		$this->post_id = \wp_insert_post(
+			array(
+				'post_author' => $this->user_id,
+				'post_content' => 'test',
+			)
+		);
+	}
+
+	public function test_object_id_to_comment_basic() {
+		$single_comment_source_id = 'https://example.com/single';
+		$content = 'example';
+		$comment_id = \wp_new_comment(
+			array(
+				'comment_post_ID' => $this->post_id,
+				'comment_author' => 'Example User',
+				'comment_author_url' => 'https://example.com/user',
+				'comment_content' => $content,
+				'comment_type' => '',
+				'comment_author_email' => '',
+				'comment_parent' => 0,
+				'comment_meta' => array(
+					'source_id' => $single_comment_source_id,
+					'source_url' => 'https://example.com/123',
+					'avatar_url' => 'https://example.com/icon',
+					'protocol' => 'activitypub',
+				),
+			),
+			true
+		);
+		$query_result = \Activitypub\object_id_to_comment( $single_comment_source_id );
+		$this->assertInstanceOf( WP_Comment::class, $query_result );
+		$this->assertEquals( $comment_id, $query_result->comment_ID );
+		$this->assertEquals( $content, $query_result->comment_content );
+	}
+
+	public function test_object_id_to_comment_none() {
+		$single_comment_source_id = 'https://example.com/none';
+		$query_result = \Activitypub\object_id_to_comment( $single_comment_source_id );
+		$this->assertFalse( $query_result );
+	}
+
+	public function test_object_id_to_comment_duplicate() {
+		$duplicate_comment_source_id = 'https://example.com/duplicate';
+		for ( $i = 0; $i < 2; ++$i ) {
+			\wp_new_comment(
+				array(
+					'comment_post_ID' => $this->post_id,
+					'comment_author' => 'Example User',
+					'comment_author_url' => 'https://example.com/user',
+					'comment_content' => 'example',
+					'comment_type' => '',
+					'comment_author_email' => '',
+					'comment_parent' => 0,
+					'comment_meta' => array(
+						'source_id' => $duplicate_comment_source_id,
+						'source_url' => 'https://example.com/123',
+						'avatar_url' => 'https://example.com/icon',
+						'protocol' => 'activitypub',
+					),
+				),
+				true
+			);
+		}
+		$query_result = \Activitypub\object_id_to_comment( $duplicate_comment_source_id );
+		$this->assertFalse( $query_result );
+	}
+
+	/**
+	 * @dataProvider object_to_uri_provider
+	 */
+	public function test_object_to_uri( $input, $output ) {
+		$this->assertEquals( $output, \Activitypub\object_to_uri( $input ) );
+	}
+
+	public function object_to_uri_provider() {
+		return array(
+			array( null, null ),
+			array( 'https://example.com', 'https://example.com' ),
+			array( array( 'https://example.com' ), 'https://example.com' ),
+			array(
+				array(
+					'https://example.com',
+					'https://example.org',
+				),
+				'https://example.com',
+			),
+			array(
+				array(
+					'type' => 'Link',
+					'href' => 'https://example.com',
+				),
+				'https://example.com',
+			),
+			array(
+				array(
+					array(
+						'type' => 'Link',
+						'href' => 'https://example.com',
+					),
+					array(
+						'type' => 'Link',
+						'href' => 'https://example.org',
+					),
+				),
+				'https://example.com',
+			),
+			array(
+				array(
+					'type' => 'Actor',
+					'id' => 'https://example.com',
+				),
+				'https://example.com',
+			),
+			array(
+				array(
+					array(
+						'type' => 'Actor',
+						'id' => 'https://example.com',
+					),
+					array(
+						'type' => 'Actor',
+						'id' => 'https://example.org',
+					),
+				),
+				'https://example.com',
+			),
+			array(
+				array(
+					'type' => 'Activity',
+					'id' => 'https://example.com',
+				),
+				'https://example.com',
+			),
+		);
+	}
 }