wordpress-activitypub/includes/functions.php
Django Doucet e4c991393d phpcbf
2023-03-10 16:27:35 -07:00

638 lines
17 KiB
PHP

<?php
namespace Activitypub;
define( 'AS_PUBLIC', 'https://www.w3.org/ns/activitystreams#Public' );
/**
* Returns the ActivityPub default JSON-context
*
* @return array the activitypub context
*/
function get_context() {
$context = array(
'https://www.w3.org/ns/activitystreams',
'https://w3id.org/security/v1',
array(
'manuallyApprovesFollowers' => 'as:manuallyApprovesFollowers',
'PropertyValue' => 'schema:PropertyValue',
'schema' => 'http://schema.org#',
'pt' => 'https://joinpeertube.org/ns#',
'toot' => 'http://joinmastodon.org/ns#',
'value' => 'schema:value',
'Hashtag' => 'as:Hashtag',
'featured' => array(
'@id' => 'toot:featured',
'@type' => '@id',
),
'featuredTags' => array(
'@id' => 'toot:featuredTags',
'@type' => '@id',
),
),
);
return \apply_filters( 'activitypub_json_context', $context );
}
function safe_remote_post( $url, $body, $user_id ) {
$date = \gmdate( 'D, d M Y H:i:s T' );
$digest = \Activitypub\Signature::generate_digest( $body );
$signature = \Activitypub\Signature::generate_signature( $user_id, 'post', $url, $date, $digest );
$wp_version = \get_bloginfo( 'version' );
$user_agent = \apply_filters( 'http_headers_useragent', 'WordPress/' . $wp_version . '; ' . \get_bloginfo( 'url' ) );
$args = array(
'timeout' => 100,
'limit_response_size' => 1048576,
'redirection' => 3,
'user-agent' => "$user_agent; ActivityPub",
'headers' => array(
'Accept' => 'application/activity+json',
'Content-Type' => 'application/activity+json',
'Digest' => "SHA-256=$digest",
'Signature' => $signature,
'Date' => $date,
),
'body' => $body,
);
$response = \wp_safe_remote_post( $url, $args );
\do_action( 'activitypub_safe_remote_post_response', $response, $url, $body, $user_id );
return $response;
}
function forward_remote_post( $url, $body, $user_id ) {
$date = \gmdate( 'D, d M Y H:i:s T' );
$digest = \Activitypub\Signature::generate_digest( $body );
$signature = \Activitypub\Signature::generate_signature( 1, $url, $date );
$wp_version = \get_bloginfo( 'version' );
$user_agent = \apply_filters( 'http_headers_useragent', 'WordPress/' . $wp_version . '; ' . \get_bloginfo( 'url' ) );
$args = array(
'timeout' => 100,
'limit_response_size' => 1048576,
'redirection' => 3,
'user-agent' => "$user_agent; ActivityPub",
'headers' => array(
'Accept' => 'application/activity+json',
'Content-Type' => 'application/activity+json',
'Digest' => "SHA-256=$digest",
'Signature' => $signature,
'Date' => $date,
),
'body' => $body,
);
$response = \wp_safe_remote_post( $url, $args );
\do_action( 'activitypub_forward_remote_post_response', $response, $url, $body, $user_id );
return $response;
}
function safe_remote_get( $url, $user_id ) {
$date = \gmdate( 'D, d M Y H:i:s T' );
$signature = \Activitypub\Signature::generate_signature( $user_id, 'get', $url, $date );
$wp_version = \get_bloginfo( 'version' );
$user_agent = \apply_filters( 'http_headers_useragent', 'WordPress/' . $wp_version . '; ' . \get_bloginfo( 'url' ) );
$args = array(
'timeout' => apply_filters( 'activitypub_remote_get_timeout', 100 ),
'limit_response_size' => 1048576,
'redirection' => 3,
'user-agent' => "$user_agent; ActivityPub",
'headers' => array(
'Accept' => 'application/activity+json',
'Content-Type' => 'application/activity+json',
'Signature' => $signature,
'Date' => $date,
),
);
$response = \wp_safe_remote_get( $url, $args );
\do_action( 'activitypub_safe_remote_get_response', $response, $url, $user_id );
return $response;
}
/**
* Returns a users WebFinger "resource"
*
* @param int $user_id
*
* @return string The user-resource
*/
function get_webfinger_resource( $user_id ) {
return \Activitypub\Webfinger::get_user_resource( $user_id );
}
/**
* [get_metadata_by_actor description]
*
* @param string $actor
*
* @return array
*/
function get_remote_metadata_by_actor( $actor ) {
$pre = apply_filters( 'pre_get_remote_metadata_by_actor', false, $actor );
if ( $pre ) {
return $pre;
}
if ( preg_match( '/^@?' . ACTIVITYPUB_USERNAME_REGEXP . '$/i', $actor ) ) {
$actor = Webfinger::resolve( $actor );
}
if ( ! $actor ) {
return null;
}
if ( is_wp_error( $actor ) ) {
return $actor;
}
$transient_key = 'activitypub_' . $actor;
$metadata = \get_transient( $transient_key );
if ( $metadata ) {
return $metadata;
}
if ( ! \wp_http_validate_url( $actor ) ) {
$metadata = new \WP_Error( 'activitypub_no_valid_actor_url', \__( 'The "actor" is no valid URL', 'activitypub' ), $actor );
\set_transient( $transient_key, $metadata, HOUR_IN_SECONDS ); // Cache the error for a shorter period.
return $metadata;
}
$user = \get_users(
array(
'number' => 1,
'capability__in' => array( 'publish_posts' ),
'fields' => 'ID',
)
);
// we just need any user to generate a request signature
$user_id = \reset( $user );
$short_timeout = function() {
return 3;
};
add_filter( 'activitypub_remote_get_timeout', $short_timeout );
$response = \Activitypub\safe_remote_get( $actor, $user_id );
remove_filter( 'activitypub_remote_get_timeout', $short_timeout );
if ( \is_wp_error( $response ) ) {
\set_transient( $transient_key, $response, HOUR_IN_SECONDS ); // Cache the error for a shorter period.
return $response;
}
$metadata = \wp_remote_retrieve_body( $response );
$metadata = \json_decode( $metadata, true );
if ( ! $metadata ) {
$metadata = new \WP_Error( 'activitypub_invalid_json', \__( 'No valid JSON data', 'activitypub' ), $actor );
\set_transient( $transient_key, $metadata, HOUR_IN_SECONDS ); // Cache the error for a shorter period.
return $metadata;
}
\set_transient( $transient_key, $metadata, WEEK_IN_SECONDS );
return $metadata;
}
/**
* [get_inbox_by_actor description]
* @param [type] $actor [description]
* @return [type] [description]
*/
function get_inbox_by_actor( $actor ) {
$metadata = \Activitypub\get_remote_metadata_by_actor( $actor );
if ( \is_wp_error( $metadata ) ) {
return $metadata;
}
if ( isset( $metadata['endpoints'] ) && isset( $metadata['endpoints']['sharedInbox'] ) ) {
return $metadata['endpoints']['sharedInbox'];
}
if ( \array_key_exists( 'inbox', $metadata ) ) {
return $metadata['inbox'];
}
return new \WP_Error( 'activitypub_no_inbox', \__( 'No "Inbox" found', 'activitypub' ), $metadata );
}
/**
* [get_inbox_by_actor description]
* @param [type] $actor [description]
* @return [type] [description]
*/
function get_publickey_by_actor( $actor, $key_id ) {
$metadata = \Activitypub\get_remote_metadata_by_actor( $actor );
if ( \is_wp_error( $metadata ) ) {
return $metadata;
}
if (
isset( $metadata['publicKey'] ) &&
isset( $metadata['publicKey']['id'] ) &&
isset( $metadata['publicKey']['owner'] ) &&
isset( $metadata['publicKey']['publicKeyPem'] ) &&
$key_id === $metadata['publicKey']['id'] &&
$actor === $metadata['publicKey']['owner']
) {
return $metadata['publicKey']['publicKeyPem'];
}
return new \WP_Error( 'activitypub_no_public_key', \__( 'No "Public-Key" found', 'activitypub' ), $metadata );
}
function get_follower_inboxes( $user_id ) {
$followers = \Activitypub\Peer\Followers::get_followers( $user_id );
$inboxes = array();
foreach ( $followers as $follower ) {
$inbox = \Activitypub\get_inbox_by_actor( $follower );
if ( ! $inbox || \is_wp_error( $inbox ) ) {
continue;
}
// init array if empty
if ( ! isset( $inboxes[ $inbox ] ) ) {
$inboxes[ $inbox ] = array();
}
$inboxes[ $inbox ][] = $follower;
}
return $inboxes;
}
/**
* @param $mentions array of mentioned actors, each mention is an array of actor URI (href), and webfinger (name).
* @return array of (shared) inboxes.
*/
function get_mentioned_inboxes( $mentions ) {
$inboxes = array();
foreach ( $mentions as $mention ) {
$inbox = \Activitypub\get_inbox_by_actor( $mention['href'] );
if ( ! $inbox || \is_wp_error( $inbox ) ) {
continue;
}
if ( ! isset( $inboxes[ $inbox ] ) ) {
$inboxes[ $inbox ] = array();
}
$inboxes[ $inbox ][] = $mention;
}
return $inboxes;
}
function get_identifier_settings( $user_id ) {
?>
<table class="form-table">
<tbody>
<tr>
<th scope="row">
<label><?php \esc_html_e( 'Profile identifier', 'activitypub' ); ?></label>
</th>
<td>
<p><code><?php echo \esc_html( \Activitypub\get_webfinger_resource( $user_id ) ); ?></code> or <code><?php echo \esc_url( \get_author_posts_url( $user_id ) ); ?></code></p>
<?php // translators: the webfinger resource ?>
<p class="description"><?php \printf( \esc_html__( 'Try to follow "@%s" by searching for it on Mastodon,Friendica & Co.', 'activitypub' ), \esc_html( \Activitypub\get_webfinger_resource( $user_id ) ) ); ?></p>
</td>
</tr>
</tbody>
</table>
<?php
}
function get_followers( $user_id ) {
$followers = \Activitypub\Peer\Followers::get_followers( $user_id );
if ( ! $followers ) {
return array();
}
return $followers;
}
function count_followers( $user_id ) {
$followers = \Activitypub\get_followers( $user_id );
return \count( $followers );
}
/**
* Examine a url and try to determine the author ID it represents.
*
* Checks are supposedly from the hosted site blog.
*
* @param string $url Permalink to check.
*
* @return int User ID, or 0 on failure.
*/
function url_to_authorid( $url ) {
global $wp_rewrite;
// check if url hase the same host
if ( \wp_parse_url( \site_url(), \PHP_URL_HOST ) !== \wp_parse_url( $url, \PHP_URL_HOST ) ) {
return 0;
}
// first, check to see if there is a 'author=N' to match against
if ( \preg_match( '/[?&]author=(\d+)/i', $url, $values ) ) {
$id = \absint( $values[1] );
if ( $id ) {
return $id;
}
}
// check to see if we are using rewrite rules
$rewrite = $wp_rewrite->wp_rewrite_rules();
// not using rewrite rules, and 'author=N' method failed, so we're out of options
if ( empty( $rewrite ) ) {
return 0;
}
// generate rewrite rule for the author url
$author_rewrite = $wp_rewrite->get_author_permastruct();
$author_regexp = \str_replace( '%author%', '', $author_rewrite );
// match the rewrite rule with the passed url
if ( \preg_match( '/https?:\/\/(.+)' . \preg_quote( $author_regexp, '/' ) . '([^\/]+)/i', $url, $match ) ) {
$user = \get_user_by( 'slug', $match[2] );
if ( $user ) {
return $user->ID;
}
}
return 0;
}
/**
* Examine a comment ID and look up an existing comment it represents.
*
* @param string $id ActivityPub object ID (usually a URL) to check.
*
* @return WP_Comment, or undef if no comment could be found.
*/
function object_id_to_comment( $id ) {
$comment_query = new \WP_Comment_Query(
array(
'meta_key' => 'source_id',
'meta_value' => $id,
)
);
if ( ! $comment_query->comments ) {
return;
}
if ( count( $comment_query->comments ) > 1 ) {
\error_log( "More than one comment under {$id}" );
return;
}
return $comment_query->comments[0];
}
/**
* Examine an activity object and find the post that the specified URL field refers to.
*
* @param string $field_name The name of the URL field in the object to query.
*
* @return int Post ID, or null on failure.
*/
function object_to_post_id_by_field_name( $object, $field_name ) {
if ( ! isset( $object['object'][ $field_name ] ) ) {
return;
}
$result = \url_to_postid( $object['object'][ $field_name ] );
if ( $result > 0 ) {
return $result;
}
}
/**
* Verify if in_replyto_url is a local Post,
* (For backwards compatibility)
*
* @param string activitypub object id URI
* @return int post_id
*/
function url_to_postid( $in_replyto_url ) {
if ( ! empty( $in_replyto_url ) ) {
$tentative_postid = \url_to_postid( $in_replyto_url );
if ( is_null( $tentative_postid ) ) {
$post_types = \get_option( 'activitypub_support_post_types', array( 'post', 'page' ) );
$query_args = array(
'type' => $post_types,
'meta_query' => array(
array(
'key' => '_activitypub_permalink_compat',
'value' => $in_replyto_url,
),
),
);
$posts_query = new \WP_Query();
$posts = $posts_query->query( $query_args );
$found_post_ids = array();
if ( $posts ) {
foreach ( $posts as $post ) {
$found_post_ids[] = $post->comment_ID;
}
return $found_post_ids[0];
}
} else {
return $tentative_postid;
}
}
return null;
}
/**
* Verify if in_replyto_url is a local comment,
* Or if it is a previously received remote comment
* (For threading comments locally)
*
* @param string activitypub object id URI
* @return int comment_id
*/
function url_to_commentid( $in_replyto_url ) {
if ( empty( $in_replyto_url ) ) {
return null;
}
//rewrite for activitypub object id simplification
$url_maybe_id = \wp_parse_url( $in_replyto_url );
if ( site_url() === $url_maybe_id['scheme'] . '://' . $url_maybe_id['host'] && ! empty( $url_maybe_id['query'] ) ) {
//is local post or comment
\parse_str( $url_maybe_id['query'], $reply_query );
if ( isset( $reply_query['replytocom'] ) ) {
//is local comment
return $reply_query['replytocom'];
}
} else {
//is remote url
//verify if in_replyto_url corresponds to a previously received comment
$comment_args = array(
'type' => 'activitypub',
'meta_query' => array(
array(
'key' => 'source_url', // $object['object']['id']
'value' => $in_replyto_url,
),
),
);
$comments_query = new \WP_Comment_Query();
$comments = $comments_query->query( $comment_args );
$found_comment_ids = array();
if ( $comments ) {
foreach ( $comments as $comment ) {
$found_comment_ids[] = $comment->comment_ID;
}
return $found_comment_ids[0];
}
}
return null;
}
/**
* Verify if url is a wp_ap_comment,
* Or if it is a previously received remote comment
* @return int comment_id
*/
function is_ap_comment() {
$comment_id = get_query_var( 'replytocom', null );
if ( ! is_null( $comment_id ) ) {
$comment = \get_comment( $comment_id );
// Only return local origin comments
if ( $comment->user_id ) {
return $comment_id;
}
}
return null;
}
/**
* Verify if url has a replies query,
* @return bool
*/
function is_ap_replies() {
$replies = get_query_var( 'replies' );
if ( $replies ) {
return $replies;
}
return null;
}
/**
* Get recipients to insert/tag in reply tag from received AP object meta
* @param string $object_id a comment_id to search
* @param boolean $post defaults to searching a comment_id
* @return string space separated webfinger of tagged users
*/
function reply_recipients( $object_id, $post = null ) {
$recipients = null;
if ( $post ) {
//post
$ap_object = \unserialize( \get_post_meta( $object_id, 'ap_object', true ) );
} else {
//comment
$ap_object = \unserialize( \get_comment_meta( $object_id, 'ap_object', true ) );
}
if ( ! empty( $ap_object ) ) {
// Replying to remote comments.
$recipients[] = \ActivityPub\url_to_webfinger( $ap_object['actor'] ); // Reply to Object actor!
if ( ! empty( $ap_object['object']['tag'] ) ) { // Reply to other tagged users.
$author_post_url = \get_author_posts_url( $ap_object['user_id'] );// ignore self tag.
foreach ( $ap_object['object']['tag'] as $tag ) { // Other tagged users
if ( $author_post_url === $tag['href'] ) {
continue;
}
if ( in_array( 'Mention', $tag ) ) {
$recipients[] = $tag['name'];
}
}
}
return implode( ' ', $recipients );
} else {
// Replying to self with others.
$comment = \get_comment( $object_id );
preg_match_all( '/@' . ACTIVITYPUB_USERNAME_REGEXP . '/', $comment->comment_content, $recipients );
return implode( ' ', $recipients[0] );
}
}
/**
* Add summary to reply
*/
function get_summary( $comment_id ) {
$ap_object = \unserialize( \get_comment_meta( $comment_id, 'ap_object', true ) );
if ( ! empty( $ap_object ) ) {
if ( ! empty( $ap_object['object']['summary'] ) ) {
return \esc_attr( $ap_object['object']['summary'] );
}
}
}
/**
* @param string $user_url
* @return string $webfinger
*/
function url_to_webfinger( $user_url ) {
$user_url = \untrailingslashit( $user_url );
$user_url_array = \explode( '/', $user_url );
$user_name = \end( $user_url_array );
$url_host = \wp_parse_url( $user_url, PHP_URL_HOST );
$webfinger = '@' . $user_name . '@' . $url_host;
return $webfinger;
}
/**
* @param $comment or $comment_id
* @return ActivityPub URI of comment
*
* AP Object ID must be unique
*
* https://www.w3.org/TR/activitypub/#obj-id
* https://github.com/tootsuite/mastodon/issues/13879
*/
function set_ap_comment_id( $comment ) {
$comment = \get_comment( $comment );
$ap_comment_id = \add_query_arg(
array(
'p' => $comment->comment_post_ID,
'replytocom' => $comment->comment_ID,
),
\trailingslashit( site_url() )
);
return $ap_comment_id;
}
/**
* Determine AP audience of incoming object
* @param string $object
* @return string audience
*/
function get_audience( $object ) {
if ( in_array( AS_PUBLIC, $object['to'] ) ) {
return 'public';
}
if ( in_array( AS_PUBLIC, $object['cc'] ) ) {
return 'unlisted';
}
if ( ! in_array( AS_PUBLIC, $object['to'] ) && ! in_array( AS_PUBLIC, $object['cc'] ) ) {
$author_post_url = get_author_posts_url( $object['user_id'] );
if ( in_array( $author_post_url, $object['cc'] ) ) {
return 'followers_only';
}
if ( in_array( $author_post_url, $object['to'] ) ) {
return 'private';
}
}
}