WP_REST_Templates_Controller::get_item() WordPress Method

	public function get_item( $request ) {
		if ( isset( $request['source'] ) && 'theme' === $request['source'] ) {
			$template = get_block_file_template( $request['id'], $this->post_type );
		} else {
			$template = get_block_template( $request['id'], $this->post_type );
		}

		if ( ! $template ) {
			return new WP_Error( 'rest_template_not_found', __( 'No templates exist with that id.' ), array( 'status' => 404 ) );
		}

		return $this->prepare_item_for_response( $template, $request );
	}