build a simple to_array converter

includes/activity/class-actor.php

@@ -7,11 +7,11 @@
 
 namespace Activitypub\Activity;
 
-class Actor extends Activity_Object {
+class Actor extends Base_Object {
 	/**
 	 * @var string
 	 */
-	protected $type = 'Object';
+	protected $type = 'Person';
 
 	/**
 	 * A reference to an ActivityStreams OrderedCollection comprised of

includes/activity/class-base-object.php

@@ -10,7 +10,7 @@ namespace Activitypub\Activity;
 use WP_Error;
 
 use function Activitypub\camel_to_snake_case;
-
+use function Activitypub\snake_to_camel_case;
 /**
  * ObjectType is an implementation of one of the
  * Activity Streams Core Types.
@@ -23,7 +23,7 @@ use function Activitypub\camel_to_snake_case;
  *
  * @see https://www.w3.org/TR/activitystreams-core/#object
  */
-class Activity_Object {
+class Base_Object {
 	/**
 	 * The object's unique global identifier
 	 *
@@ -562,4 +562,31 @@ class Activity_Object {
 
 		return $object;
 	}
+
+	/**
+	 * Convert Object to an array.
+	 *
+	 * It tries to get the object attributes if they exist
+	 * and falls back to the getters. Empty values are ignored.
+	 *
+	 * @return array An array built from the Object.
+	 */
+	public function to_array() {
+		$array = array();
+		$vars  = get_object_vars( $this );
+
+		foreach ( $vars as $key => $value ) {
+			// if value is empty, try to get it from a getter.
+			if ( ! $value ) {
+				$value = call_user_func( array( $this, 'get_' . $key ) );
+			}
+
+			// if value is still empty, ignore it for the array and continue.
+			if ( $value ) {
+				$array[ snake_to_camel_case( $key ) ] = $value;
+			}
+		}
+
+		return $array;
+	}
 }

includes/activity/class-person.php

@@ -12,7 +12,7 @@ namespace Activitypub\Activity;
  *
  * @see https://www.w3.org/TR/activitystreams-vocabulary/#dfn-person
  */
-class Person extends Activity_Object {
+class Person extends Base_Object {
 	/**
 	 * @var string
 	 */

includes/functions.php

@@ -248,6 +248,17 @@ function camel_to_snake_case( $string ) {
 	return strtolower( preg_replace( '/(?<!^)[A-Z]/', '_$0', $string ) );
 }
 
+/**
+ * Convert a string from snake_case to camelCase.
+ *
+ * @param string $string The string to convert.
+ *
+ * @return string The converted string.
+ */
+function snake_to_camel_case( $string ) {
+	return lcfirst( str_replace( '_', '', ucwords( $string, '_' ) ) );
+}
+
 /**
  * Check if a request is for an ActivityPub request.
  *

tests/test-class-activitypub-activity.php

@@ -28,4 +28,17 @@ class Test_Activitypub_Activity extends WP_UnitTestCase {
 		remove_all_filters( 'activitypub_extract_mentions' );
 		\wp_trash_post( $post );
 	}
+
+	public function test_object_transformation() {
+		$test_array = array(
+			'id'      => 'https://example.com/post/123',
+			'type'    => 'Note',
+			'content' => 'Hello world!',
+		);
+
+		$object = \Activitypub\Activity\Base_Object::from_array( $test_array );
+
+		$this->assertEquals( 'Hello world!', $object->get_content() );
+		$this->assertEquals( $test_array, $object->to_array() );
+	}
 }