Add 'Feed Author' field when editing Feed.

Where available, this value is pulled from the RSS feed, using
the heuristics in SimplePie's `get_authors()` method.

Incoming feed items that do not have an associated author
fall back on the feed's author.

See #582.

Core/API/FeedEndpoint.php

@@ -183,6 +183,26 @@ public function register_rest_fields() {
 				],
 			]
 		);
+
+		register_rest_field(
+			$this->post_type,
+			'feed_author',
+			[
+				'get_callback'    => function ( $post_object ) {
+					$feed_object = Feed::get_instance_by_id( $post_object['id'] );
+					return $feed_object->get_feed_author();
+				},
+				'update_callback' => function ( $value, $post ) {
+					$feed_object = Feed::get_instance_by_id( $post->ID );
+					$feed_object->set_feed_author( $value );
+				},
+				'schema'          => [
+					'description' => __( 'The author of the feed', 'pressforward' ),
+					'type'        => 'string',
+					'context'     => [ 'view', 'edit' ],
+				],
+			]
+		);
 	}
 
 	/**

Core/Models/Feed.php

@@ -349,6 +349,45 @@ public function retrieve() {
 		return pressforward( 'schema.feed_item' )->assemble_feed_for_pull( $feed_data_object );
 	}
 
+	/**
+	 * Gets the feed author for the feed.
+	 *
+	 * @since 5.8.0
+	 *
+	 * @return string
+	 */
+	public function get_feed_author() {
+		$feed_author_meta = get_post_meta( $this->get( 'id' ), 'feed_author', true );
+
+		if ( is_string( $feed_author_meta ) ) {
+			return $feed_author_meta;
+		}
+
+		// Legacy items have feed_author saved as a SimplePie Author object.
+		if ( is_object( $feed_author_meta ) ) {
+			// May be an incomplete class.
+			$feed_author_meta = (array) $feed_author_meta;
+			if ( isset( $feed_author_meta['name'] ) ) {
+				update_post_meta( $this->get( 'id' ), 'feed_author', $feed_author_meta['name'] );
+				return $feed_author_meta['name'];
+			}
+		}
+
+		return '';
+	}
+
+	/**
+	 * Sets the feed author for the feed.
+	 *
+	 * @since 5.8.0
+	 *
+	 * @param string $author Author name.
+	 * @return void
+	 */
+	public function set_feed_author( $author ) {
+		update_post_meta( $this->get( 'id' ), 'feed_author', $author );
+	}
+
 	/**
 	 * Gets the module to be used for this feed.
 	 *
@@ -416,7 +455,11 @@ public function health_check( $is_new_feed = false ) {
 			$this->set( 'title', $the_feed->get_title() );
 			$this->set( 'description', $the_feed->get_description() );
 			$this->set( 'htmlUrl', $the_feed->get_link( 0 ) );
-			$this->set( 'feed_author', $the_feed->get_author() );
+
+			$author      = $the_feed->get_author();
+			$author_name = method_exists( $author, 'get_name' ) ? $author->get_name() : '';
+			$this->set( 'feed_author', $author_name );
+
 			$this->set( 'thumbnail', $the_feed->get_image_url() );
 
 			$this->save();

assets/src/block-editor-feeds/block-editor-feeds.js

@@ -16,15 +16,18 @@ const BlockEditorFeedsInfobox = ( {} ) => {
 
 	const {
 		errorMessage,
+		feedAuthor,
 		feedUrl,
 		postType
 	} = useSelect( ( select ) => {
 		const editedPostId = select( 'core/editor' ).getCurrentPostId()
 		const editedPostMeta = select( 'core/editor' ).getEditedPostAttribute( 'meta' )
 		const editedErrorMessage = select( 'core/editor' ).getEditedPostAttribute( 'alert_message' )
+		const editedFeedAuthor = select( 'core/editor' ).getEditedPostAttribute( 'feed_author' )
 
 		return {
 			errorMessage: editedErrorMessage,
+			feedAuthor: editedFeedAuthor,
 			feedUrl: editedPostMeta?.feed_url || '',
 			postId: editedPostId,
 			postType: select( 'core/editor' ).getEditedPostAttribute( 'type' ),
@@ -52,6 +55,15 @@ const BlockEditorFeedsInfobox = ( {} ) => {
 				} }
 			/>
 
+			<TextControl
+				label={ __( 'Feed Author', 'pressforward' ) }
+				value={ feedAuthor }
+				onChange={ ( newValue ) => {
+					editPost( { 'feed_author': newValue } )
+				} }
+				help={ __( 'Incoming items without an author name will use this value.', 'pressforward' ) }
+			/>
+
 			{ errorMessage && (
 				<p className="pf-error-message">
 					<strong>

modules/rss-import/rss-import.php

@@ -212,6 +212,15 @@ public function get_data_object( $a_feed ) {
 
 				if ( ! $ag_status ) {
 					$authors = $this->get_rss_authors( $item );
+
+					if ( __( 'No author.', 'pressforward' ) === $authors ) {
+						// See if the parent feed has an author.
+						$parent_feed_obj    = pressforward( 'schema.feeds' )->get_instance_by_id( $a_feed->ID );
+						$parent_feed_author = $parent_feed_obj->get_feed_author();
+						if ( ! empty( $parent_feed_author ) ) {
+							$authors = $parent_feed_author;
+						}
+					}
 				} else {
 					$parent_value = pressforward( 'controller.metas' )->get_post_pf_meta( $a_feed->ID, 'pf_feed_default_author', true );
 					if ( ! empty( $parent_value ) ) {