rest_filter_response_fields( WP_REST_Response $response, WP_REST_Server $server, WP_REST_Request $request ): WP_REST_Response

Compatibility

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Parameters

$responseWP_REST_Response

Current response being served.

$serverWP_REST_Server

ResponseHandler instance (usually WP_REST_Server).

$requestWP_REST_Request

The request that was used to make current response.

Return value

WP_REST_Response

Response to be served, trimmed down to contain a subset of fields.

Performance profile

How much work a call to rest_filter_response_fields() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class

Light

Touches nothing outside its own arguments.

Scaling

Scales with input

The body loops, so the work grows with what you pass in.

Instructions

6–61

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 91.

Plugin surface

None

Nothing here hands control to plugin code.

Called by

0

Nothing in core calls this; the cost is only what you spend yourself.

What one call costs · 7 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost rest_filter_response_fields() can have, taken from its control-flow graph on PHP 8.5.

Uses · 3

• wp_parse_list()Converts a comma- or space-separated list of scalar values to an array.
• wp_is_numeric_array()Determines if the variable is a numeric-indexed array.
• _rest_array_intersect_key_recursive()Recursively computes the intersection of arrays using keys for comparison.

Source code

View on Trac ↗View on GitHub ↗

929function rest_filter_response_fields( $response, $server, $request ) {930	if ( ! isset( $request['_fields'] ) || $response->is_error() ) {931		return $response;932	}933 934	$data = $response->get_data();935 936	$fields = wp_parse_list( $request['_fields'] );937 938	if ( 0 === count( $fields ) ) {939		return $response;940	}941 942	// Trim off outside whitespace from the comma delimited list.943	$fields = array_map( 'trim', $fields );944 945	// Create nested array of accepted field hierarchy.946	$fields_as_keyed = array();947	foreach ( $fields as $field ) {948		$parts = explode( '.', $field );949		$ref   = &$fields_as_keyed;950		while ( count( $parts ) > 1 ) {951			$next = array_shift( $parts );952			if ( isset( $ref[ $next ] ) && true === $ref[ $next ] ) {953				// Skip any sub-properties if their parent prop is already marked for inclusion.954				break 2;955			}956			$ref[ $next ] = isset( $ref[ $next ] ) ? $ref[ $next ] : array();957			$ref          = &$ref[ $next ];958		}959		$last         = array_shift( $parts );960		$ref[ $last ] = true;961	}962 963	if ( wp_is_numeric_array( $data ) ) {964		$new_data = array();965		foreach ( $data as $item ) {966			$new_data[] = _rest_array_intersect_key_recursive( $item, $fields_as_keyed );967		}968	} else {969		$new_data = _rest_array_intersect_key_recursive( $data, $fields_as_keyed );970	}971 972	$response->set_data( $new_data );973 974	return $response;975}

Changelog

Introduced in 4.8.0. Unchanged from 6.7.7 through 7.1.0.

1. 6.7.7
2. 6.8.8
3. 6.9.7
4. 7.0.4
5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data

Generated from the wordpress-develop 6.8.8 tag, from src/wp-includes/rest-api.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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