WP_REST_Controller::get_fields_for_response() │ public │ WP 4.9.6

Gets an array of fields to be included on the response.

Included fields are based on item schema and _fields= request argument.

Method of the class: WP_REST_Controller{}

No Hooks.

Return

String[]. Fields to be included in the response.

Usage

$WP_REST_Controller = new WP_REST_Controller();
$WP_REST_Controller->get_fields_for_response( $request );

$request(WP_REST_Request) (required)

Full details about the request.

Changelog

WP_REST_Controller::get_fields_for_response() WP REST Controller::get fields for response code ^{WP 6.5.2}

public function get_fields_for_response( $request ) {
	$schema     = $this->get_item_schema();
	$properties = isset( $schema['properties'] ) ? $schema['properties'] : array();

	$additional_fields = $this->get_additional_fields();

	foreach ( $additional_fields as $field_name => $field_options ) {
		/*
		 * For back-compat, include any field with an empty schema
		 * because it won't be present in $this->get_item_schema().
		 */
		if ( is_null( $field_options['schema'] ) ) {
			$properties[ $field_name ] = $field_options;
		}
	}

	// Exclude fields that specify a different context than the request context.
	$context = $request['context'];
	if ( $context ) {
		foreach ( $properties as $name => $options ) {
			if ( ! empty( $options['context'] ) && ! in_array( $context, $options['context'], true ) ) {
				unset( $properties[ $name ] );
			}
		}
	}

	$fields = array_keys( $properties );

	/*
	 * '_links' and '_embedded' are not typically part of the item schema,
	 * but they can be specified in '_fields', so they are added here as a
	 * convenience for checking with rest_is_field_included().
	 */
	$fields[] = '_links';
	if ( $request->has_param( '_embed' ) ) {
		$fields[] = '_embedded';
	}

	$fields = array_unique( $fields );

	if ( ! isset( $request['_fields'] ) ) {
		return $fields;
	}
	$requested_fields = wp_parse_list( $request['_fields'] );
	if ( 0 === count( $requested_fields ) ) {
		return $fields;
	}
	// Trim off outside whitespace from the comma delimited list.
	$requested_fields = array_map( 'trim', $requested_fields );
	// Always persist 'id', because it can be needed for add_additional_fields_to_object().
	if ( in_array( 'id', $fields, true ) ) {
		$requested_fields[] = 'id';
	}
	// Return the list of all requested fields which appear in the schema.
	return array_reduce(
		$requested_fields,
		static function ( $response_fields, $field ) use ( $fields ) {
			if ( in_array( $field, $fields, true ) ) {
				$response_fields[] = $field;
				return $response_fields;
			}
			// Check for nested fields if $field is not a direct match.
			$nested_fields = explode( '.', $field );
			/*
			 * A nested field is included so long as its top-level property
			 * is present in the schema.
			 */
			if ( in_array( $nested_fields[0], $fields, true ) ) {
				$response_fields[] = $field;
			}
			return $response_fields;
		},
		array()
	);
}