WP_REST_Server::get_index( WP_REST_Request $request ): WP_REST_Response

Description

Compatibility

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

Parameters

$requestWP_REST_Request

Request data.

Return value

WP_REST_Response

The API root index data.

Performance profile

How much work a call to WP_REST_Server::get_index() 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

Moderate

Reads stored settings via get_option(), cached per request but not free on a cold cache.

Scaling

Constant

No loop in the body: the same number of instructions runs whatever you pass in.

Instructions

97–114

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 129.

Plugin surface

1 hook

Third-party callbacks on 'rest_index' run inside this call, and their cost is not bounded by anything here.

Called by

0

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

What it touches

• optionoption read or writeget_option()called directly
• hookthird-party callbacksapply_filters()called directly
• cacheobject cachewp_cache_get()one call below WP_REST_Server::get_index()
• serializeserialisationmaybe_unserialize()one call below WP_REST_Server::get_index()

Further down the call graph this can also reach query and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.

What one call costs · 8 distinct outcomes

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

Hooks and filters fired · 1

One hook fires while WP_REST_Server::get_index() runs, in this order:

1. 1
   apply_filters( rest_index )filterline 1421 (+56 into the body)

   Filters the REST API root index data.

Uses · 11

• get_option()Retrieves an option value based on an option name.
• home_url()Retrieves the URL for the current site where the front end is accessible.
• wp_parse_list()Converts a comma- or space-separated list of scalar values to an array.
• rest_is_field_included()Given an array of fields to include in a response, some of which may be `nested.fields`, determine whether the provided field should be included in the response body.
• apply_filters()Calls the callback functions that have been added to a filter hook.
• WP_REST_Server::get_data_for_routes()Retrieves the publicly-visible data for routes.
• WP_REST_Server::get_routes()Retrieves the route map.
• WP_REST_Response::__construct()
• WP_REST_Server::add_active_theme_link_to_index()Adds a link to the active theme for users who have proper permissions.
• WP_REST_Server::add_site_logo_to_index()Exposes the site logo through the WordPress REST API.
• WP_REST_Server::add_site_icon_to_index()Exposes the site icon through the WordPress REST API.

Source code

View on Trac ↗View on GitHub ↗

1365	public function get_index( $request ) {1366		// General site data.1367		$available = array(1368			'name'            => get_option( 'blogname' ),1369			'description'     => get_option( 'blogdescription' ),1370			'url'             => get_option( 'siteurl' ),1371			'home'            => home_url(),1372			'gmt_offset'      => get_option( 'gmt_offset' ),1373			'timezone_string' => get_option( 'timezone_string' ),1374			'page_for_posts'  => (int) get_option( 'page_for_posts' ),1375			'page_on_front'   => (int) get_option( 'page_on_front' ),1376			'show_on_front'   => get_option( 'show_on_front' ),1377			'namespaces'      => array_keys( $this->namespaces ),1378			'authentication'  => array(),1379			'routes'          => $this->get_data_for_routes( $this->get_routes(), $request['context'] ),1380		);1381 1382		$response = new WP_REST_Response( $available );1383 1384		$fields = isset( $request['_fields'] ) ? $request['_fields'] : '';1385		$fields = wp_parse_list( $fields );1386		if ( empty( $fields ) ) {1387			$fields[] = '_links';1388		}1389 1390		if ( $request->has_param( '_embed' ) ) {1391			$fields[] = '_embedded';1392		}1393 1394		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {1395			$response->add_link( 'help', 'https://developer.wordpress.org/rest-api/' );1396			$this->add_active_theme_link_to_index( $response );1397			$this->add_site_logo_to_index( $response );1398			$this->add_site_icon_to_index( $response );1399		} else {1400			if ( rest_is_field_included( 'site_logo', $fields ) ) {1401				$this->add_site_logo_to_index( $response );1402			}1403			if ( rest_is_field_included( 'site_icon', $fields ) || rest_is_field_included( 'site_icon_url', $fields ) ) {1404				$this->add_site_icon_to_index( $response );1405			}1406		}1407 1408		/**1409		 * Filters the REST API root index data.1410		 *1411		 * This contains the data describing the API. This includes information1412		 * about supported authentication schemes, supported namespaces, routes1413		 * available on the API, and a small amount of data about the site.1414		 *1415		 * @since 4.4.01416		 * @since 6.0.0 Added `$request` parameter.1417		 *1418		 * @param WP_REST_Response $response Response data.1419		 * @param WP_REST_Request  $request  Request data.1420		 */1421		return apply_filters( 'rest_index', $response, $request );1422	}

Changelog

Introduced in 4.4.0. One change between 6.7.7 and 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 6.9.7 tag, from src/wp-includes/rest-api/class-wp-rest-server.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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