wp_xmlrpc_server::get_custom_fields( int $post_id )

	public function get_custom_fields($post_id) {
		$post_id = (int) $post_id;

		$custom_fields = array();

		foreach ( (array) has_meta($post_id) as $meta ) {
			// Don't expose protected fields.
			if ( ! current_user_can( 'edit_post_meta', $post_id , $meta['meta_key'] ) )
				continue;

			$custom_fields[] = array(
				"id"    => $meta['meta_id'],
				"key"   => $meta['meta_key'],
				"value" => $meta['meta_value']
			);
		}

		return $custom_fields;
	}