add draft for example transformer

Transformers/index.md

@@ -6,18 +6,18 @@ The WordPress ActivityPub plugin comes with a built-in transformer which lets yo
 
 Other plugins can register new transformers and unregister existing ones.
 
-* [Add New Transformer](./add-transformer/)
+* [Add New Transformer](./add-transformer.md/)
-* [Remove Transformer](./remove-transformer/)
+* [Remove Transformer](./remove-transformer.md/)
 
 ## Creating New Transformers
 
 Learn more about transformer anatomy and how to create your own:
 
-* [Transformer Structure](./transformer-structure/)
+* [Transformer Structure](./transformer-structure.md/)
 
 
 ## Code Examples
 
 See the following examples to see how easy it is.
 
-* [The Events Calendar](./simple-example/)
+* [The Events Calendar](./the-events-calendar-example.md/)

Transformers/the-events-calendar-example.md

@@ -0,0 +1,115 @@
+## Folder Structure
+You need at least two files. One file for the transformer itself and one file for registering it.
+```
+activitypub-tribe-transformer/
+|
+├─ activitypub/
+|  └─ transformer/
+|     └─ tribe.php
+|
+└─ activitypub-tribe-transformer.php
+```
+
+## Plugin Files
+**activitypub-tribe-transformer-php**
+```php
+<?php
+/**
+ * Plugin Name: ActivityPub Transformer for The Events Calendar
+ * Description: Transforms tribe_event posts to ActivityPub object of type Event.
+ * Plugin URI:  https://event-federation.eu/
+ * Version:     1.0.0
+ * Author:      WordPress ActivityPub Enthusiast
+ * Author URI:  https://event-federation.eu
+ * Text Domain: activitypub-tribe-transformer
+ *
+    * ActivityPub tested up to: 1.2.0
+    */
+
+if ( ! defined( 'ABSPATH' ) ) {
+	exit; // Exit if accessed directly.
+}
+
+/**
+ * Register Tribe Transformer.
+ *
+ * Include transformer file and register transformer class.
+ *
+ * @since 1.0.0
+ * @param \Activitypub\Transformer\Transformers_Manager $transformers_manager ActivtiyPub transformers manager.
+ * @return void
+ */
+function register_tribe_transformer( $transformers_manager ) {
+	require_once( __DIR__ . '/activitypub/transformer/tribe.php' );
+	$transformers_manager->register( new \Tribe() );
+}
+
+add_action( 'activitypub_transformers_register', 'register_tribe_transformer' );
+```
+
+**activtiypub/transformer/tribe.php**
+```php
+<?php
+if ( ! defined( 'ABSPATH' ) ) {
+	exit; // Exit if accessed directly.
+}
+
+/**
+ * ActivityPub Tribe Transformer
+ *
+ * @since 1.0.0
+ */
+class Tribe extends \Activitypub\Transformer\Base {
+
+	/**
+	 * Get widget name.
+	 *
+	 * Retrieve oEmbed widget name.
+	 *
+	 * @since 1.0.0
+	 * @access public
+	 * @return string Widget name.
+	 */
+	public function get_name() {
+		return 'activitypub-tribe/tribe';
+	}
+
+	/**
+	 * Get widget title.
+	 *
+	 * Retrieve Transformer title.
+	 *
+	 * @since 1.0.0
+	 * @access public
+	 * @return string Widget title.
+	 */
+	public function get_label() {
+		return 'The Events Calendar';
+	}
+
+	/**
+	 * Returns the ActivityStreams 2.0 Object-Type for an Event.
+	 *
+	 * @see https://www.w3.org/TR/activitystreams-vocabulary/#dfn-event
+	 *
+	 * @return string The Event Object-Type.
+	 */
+	protected function get_object_type() {
+		return 'Event';
+	}
+
+	/**
+	 * Get supported post types.
+	 *
+	 * Retrieve the list of supported WordPress post types this transformer widget can handle.
+	 *
+	 * @since 1.0.0
+	 * @access public
+	 * @return array Widget categories.
+	 */
+	public function get_supported_post_types() {
+		return [ 'tribe_events' ];
+	}
+
+}
+```