Added wordpress

1 files changed, 1564 insertions, 0 deletions

diff --git a/srcs/wordpress/wp-includes/rest-api.php b/srcs/wordpress/wp-includes/rest-api.php
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+<?php
+/**
+ * REST API functions.
+ *
+ * @package WordPress
+ * @subpackage REST_API
+ * @since 4.4.0
+ */
+
+/**
+ * Version number for our API.
+ *
+ * @var string
+ */
+define( 'REST_API_VERSION', '2.0' );
+
+/**
+ * Registers a REST API route.
+ *
+ * Note: Do not use before the {@see 'rest_api_init'} hook.
+ *
+ * @since 4.4.0
+ * @since 5.1.0 Added a _doing_it_wrong() notice when not called on or after the rest_api_init hook.
+ *
+ * @param string $namespace The first URL segment after core prefix. Should be unique to your package/plugin.
+ * @param string $route     The base URL for route you are adding.
+ * @param array  $args      Optional. Either an array of options for the endpoint, or an array of arrays for
+ *                          multiple methods. Default empty array.
+ * @param bool   $override  Optional. If the route already exists, should we override it? True overrides,
+ *                          false merges (with newer overriding if duplicate keys exist). Default false.
+ * @return bool True on success, false on error.
+ */
+function register_rest_route( $namespace, $route, $args = array(), $override = false ) {
+	if ( empty( $namespace ) ) {
+		/*
+		 * Non-namespaced routes are not allowed, with the exception of the main
+		 * and namespace indexes. If you really need to register a
+		 * non-namespaced route, call `WP_REST_Server::register_route` directly.
+		 */
+		_doing_it_wrong( 'register_rest_route', __( 'Routes must be namespaced with plugin or theme name and version.' ), '4.4.0' );
+		return false;
+	} elseif ( empty( $route ) ) {
+		_doing_it_wrong( 'register_rest_route', __( 'Route must be specified.' ), '4.4.0' );
+		return false;
+	}
+
+	if ( ! did_action( 'rest_api_init' ) ) {
+		_doing_it_wrong(
+			'register_rest_route',
+			sprintf(
+				/* translators: %s: rest_api_init */
+				__( 'REST API routes must be registered on the %s action.' ),
+				'<code>rest_api_init</code>'
+			),
+			'5.1.0'
+		);
+	}
+
+	if ( isset( $args['args'] ) ) {
+		$common_args = $args['args'];
+		unset( $args['args'] );
+	} else {
+		$common_args = array();
+	}
+
+	if ( isset( $args['callback'] ) ) {
+		// Upgrade a single set to multiple.
+		$args = array( $args );
+	}
+
+	$defaults = array(
+		'methods'  => 'GET',
+		'callback' => null,
+		'args'     => array(),
+	);
+	foreach ( $args as $key => &$arg_group ) {
+		if ( ! is_numeric( $key ) ) {
+			// Route option, skip here.
+			continue;
+		}
+
+		$arg_group         = array_merge( $defaults, $arg_group );
+		$arg_group['args'] = array_merge( $common_args, $arg_group['args'] );
+	}
+
+	$full_route = '/' . trim( $namespace, '/' ) . '/' . trim( $route, '/' );
+	rest_get_server()->register_route( $namespace, $full_route, $args, $override );
+	return true;
+}
+
+/**
+ * Registers a new field on an existing WordPress object type.
+ *
+ * @since 4.7.0
+ *
+ * @global array $wp_rest_additional_fields Holds registered fields, organized
+ *                                          by object type.
+ *
+ * @param string|array $object_type Object(s) the field is being registered
+ *                                  to, "post"|"term"|"comment" etc.
+ * @param string $attribute         The attribute name.
+ * @param array  $args {
+ *     Optional. An array of arguments used to handle the registered field.
+ *
+ *     @type callable|null $get_callback    Optional. The callback function used to retrieve the field value. Default is
+ *                                          'null', the field will not be returned in the response. The function will
+ *                                          be passed the prepared object data.
+ *     @type callable|null $update_callback Optional. The callback function used to set and update the field value. Default
+ *                                          is 'null', the value cannot be set or updated. The function will be passed
+ *                                          the model object, like WP_Post.
+ *     @type array|null $schema             Optional. The callback function used to create the schema for this field.
+ *                                          Default is 'null', no schema entry will be returned.
+ * }
+ */
+function register_rest_field( $object_type, $attribute, $args = array() ) {
+	$defaults = array(
+		'get_callback'    => null,
+		'update_callback' => null,
+		'schema'          => null,
+	);
+
+	$args = wp_parse_args( $args, $defaults );
+
+	global $wp_rest_additional_fields;
+
+	$object_types = (array) $object_type;
+
+	foreach ( $object_types as $object_type ) {
+		$wp_rest_additional_fields[ $object_type ][ $attribute ] = $args;
+	}
+}
+
+/**
+ * Registers rewrite rules for the API.
+ *
+ * @since 4.4.0
+ *
+ * @see rest_api_register_rewrites()
+ * @global WP $wp Current WordPress environment instance.
+ */
+function rest_api_init() {
+	rest_api_register_rewrites();
+
+	global $wp;
+	$wp->add_query_var( 'rest_route' );
+}
+
+/**
+ * Adds REST rewrite rules.
+ *
+ * @since 4.4.0
+ *
+ * @see add_rewrite_rule()
+ * @global WP_Rewrite $wp_rewrite WordPress rewrite component.
+ */
+function rest_api_register_rewrites() {
+	global $wp_rewrite;
+
+	add_rewrite_rule( '^' . rest_get_url_prefix() . '/?$', 'index.php?rest_route=/', 'top' );
+	add_rewrite_rule( '^' . rest_get_url_prefix() . '/(.*)?', 'index.php?rest_route=/$matches[1]', 'top' );
+	add_rewrite_rule( '^' . $wp_rewrite->index . '/' . rest_get_url_prefix() . '/?$', 'index.php?rest_route=/', 'top' );
+	add_rewrite_rule( '^' . $wp_rewrite->index . '/' . rest_get_url_prefix() . '/(.*)?', 'index.php?rest_route=/$matches[1]', 'top' );
+}
+
+/**
+ * Registers the default REST API filters.
+ *
+ * Attached to the {@see 'rest_api_init'} action
+ * to make testing and disabling these filters easier.
+ *
+ * @since 4.4.0
+ */
+function rest_api_default_filters() {
+	// Deprecated reporting.
+	add_action( 'deprecated_function_run', 'rest_handle_deprecated_function', 10, 3 );
+	add_filter( 'deprecated_function_trigger_error', '__return_false' );
+	add_action( 'deprecated_argument_run', 'rest_handle_deprecated_argument', 10, 3 );
+	add_filter( 'deprecated_argument_trigger_error', '__return_false' );
+
+	// Default serving.
+	add_filter( 'rest_pre_serve_request', 'rest_send_cors_headers' );
+	add_filter( 'rest_post_dispatch', 'rest_send_allow_header', 10, 3 );
+	add_filter( 'rest_post_dispatch', 'rest_filter_response_fields', 10, 3 );
+
+	add_filter( 'rest_pre_dispatch', 'rest_handle_options_request', 10, 3 );
+}
+
+/**
+ * Registers default REST API routes.
+ *
+ * @since 4.7.0
+ */
+function create_initial_rest_routes() {
+	foreach ( get_post_types( array( 'show_in_rest' => true ), 'objects' ) as $post_type ) {
+		$controller = $post_type->get_rest_controller();
+
+		if ( ! $controller ) {
+			continue;
+		}
+
+		$controller->register_routes();
+
+		if ( post_type_supports( $post_type->name, 'revisions' ) ) {
+			$revisions_controller = new WP_REST_Revisions_Controller( $post_type->name );
+			$revisions_controller->register_routes();
+		}
+
+		if ( 'attachment' !== $post_type->name ) {
+			$autosaves_controller = new WP_REST_Autosaves_Controller( $post_type->name );
+			$autosaves_controller->register_routes();
+		}
+	}
+
+	// Post types.
+	$controller = new WP_REST_Post_Types_Controller;
+	$controller->register_routes();
+
+	// Post statuses.
+	$controller = new WP_REST_Post_Statuses_Controller;
+	$controller->register_routes();
+
+	// Taxonomies.
+	$controller = new WP_REST_Taxonomies_Controller;
+	$controller->register_routes();
+
+	// Terms.
+	foreach ( get_taxonomies( array( 'show_in_rest' => true ), 'object' ) as $taxonomy ) {
+		$class = ! empty( $taxonomy->rest_controller_class ) ? $taxonomy->rest_controller_class : 'WP_REST_Terms_Controller';
+
+		if ( ! class_exists( $class ) ) {
+			continue;
+		}
+		$controller = new $class( $taxonomy->name );
+		if ( ! is_subclass_of( $controller, 'WP_REST_Controller' ) ) {
+			continue;
+		}
+
+		$controller->register_routes();
+	}
+
+	// Users.
+	$controller = new WP_REST_Users_Controller;
+	$controller->register_routes();
+
+	// Comments.
+	$controller = new WP_REST_Comments_Controller;
+	$controller->register_routes();
+
+	/**
+	 * Filters the search handlers to use in the REST search controller.
+	 *
+	 * @since 5.0.0
+	 *
+	 * @param array $search_handlers List of search handlers to use in the controller. Each search
+	 *                               handler instance must extend the `WP_REST_Search_Handler` class.
+	 *                               Default is only a handler for posts.
+	 */
+	$search_handlers = apply_filters( 'wp_rest_search_handlers', array( new WP_REST_Post_Search_Handler() ) );
+
+	$controller = new WP_REST_Search_Controller( $search_handlers );
+	$controller->register_routes();
+
+	// Block Renderer.
+	$controller = new WP_REST_Block_Renderer_Controller;
+	$controller->register_routes();
+
+	// Settings.
+	$controller = new WP_REST_Settings_Controller;
+	$controller->register_routes();
+
+	// Themes.
+	$controller = new WP_REST_Themes_Controller;
+	$controller->register_routes();
+
+}
+
+/**
+ * Loads the REST API.
+ *
+ * @since 4.4.0
+ *
+ * @global WP $wp Current WordPress environment instance.
+ */
+function rest_api_loaded() {
+	if ( empty( $GLOBALS['wp']->query_vars['rest_route'] ) ) {
+		return;
+	}
+
+	/**
+	 * Whether this is a REST Request.
+	 *
+	 * @since 4.4.0
+	 * @var bool
+	 */
+	define( 'REST_REQUEST', true );
+
+	// Initialize the server.
+	$server = rest_get_server();
+
+	// Fire off the request.
+	$route = untrailingslashit( $GLOBALS['wp']->query_vars['rest_route'] );
+	if ( empty( $route ) ) {
+		$route = '/';
+	}
+	$server->serve_request( $route );
+
+	// We're done.
+	die();
+}
+
+/**
+ * Retrieves the URL prefix for any API resource.
+ *
+ * @since 4.4.0
+ *
+ * @return string Prefix.
+ */
+function rest_get_url_prefix() {
+	/**
+	 * Filters the REST URL prefix.
+	 *
+	 * @since 4.4.0
+	 *
+	 * @param string $prefix URL prefix. Default 'wp-json'.
+	 */
+	return apply_filters( 'rest_url_prefix', 'wp-json' );
+}
+
+/**
+ * Retrieves the URL to a REST endpoint on a site.
+ *
+ * Note: The returned URL is NOT escaped.
+ *
+ * @since 4.4.0
+ *
+ * @todo Check if this is even necessary
+ * @global WP_Rewrite $wp_rewrite WordPress rewrite component.
+ *
+ * @param int    $blog_id Optional. Blog ID. Default of null returns URL for current blog.
+ * @param string $path    Optional. REST route. Default '/'.
+ * @param string $scheme  Optional. Sanitization scheme. Default 'rest'.
+ * @return string Full URL to the endpoint.
+ */
+function get_rest_url( $blog_id = null, $path = '/', $scheme = 'rest' ) {
+	if ( empty( $path ) ) {
+		$path = '/';
+	}
+
+	$path = '/' . ltrim( $path, '/' );
+
+	if ( is_multisite() && get_blog_option( $blog_id, 'permalink_structure' ) || get_option( 'permalink_structure' ) ) {
+		global $wp_rewrite;
+
+		if ( $wp_rewrite->using_index_permalinks() ) {
+			$url = get_home_url( $blog_id, $wp_rewrite->index . '/' . rest_get_url_prefix(), $scheme );
+		} else {
+			$url = get_home_url( $blog_id, rest_get_url_prefix(), $scheme );
+		}
+
+		$url .= $path;
+	} else {
+		$url = trailingslashit( get_home_url( $blog_id, '', $scheme ) );
+		// nginx only allows HTTP/1.0 methods when redirecting from / to /index.php
+		// To work around this, we manually add index.php to the URL, avoiding the redirect.
+		if ( 'index.php' !== substr( $url, 9 ) ) {
+			$url .= 'index.php';
+		}
+
+		$url = add_query_arg( 'rest_route', $path, $url );
+	}
+
+	if ( is_ssl() && isset( $_SERVER['SERVER_NAME'] ) ) {
+		// If the current host is the same as the REST URL host, force the REST URL scheme to HTTPS.
+		if ( $_SERVER['SERVER_NAME'] === parse_url( get_home_url( $blog_id ), PHP_URL_HOST ) ) {
+			$url = set_url_scheme( $url, 'https' );
+		}
+	}
+
+	if ( is_admin() && force_ssl_admin() ) {
+		// In this situation the home URL may be http:, and `is_ssl()` may be
+		// false, but the admin is served over https: (one way or another), so
+		// REST API usage will be blocked by browsers unless it is also served
+		// over HTTPS.
+		$url = set_url_scheme( $url, 'https' );
+	}
+
+	/**
+	 * Filters the REST URL.
+	 *
+	 * Use this filter to adjust the url returned by the get_rest_url() function.
+	 *
+	 * @since 4.4.0
+	 *
+	 * @param string $url     REST URL.
+	 * @param string $path    REST route.
+	 * @param int    $blog_id Blog ID.
+	 * @param string $scheme  Sanitization scheme.
+	 */
+	return apply_filters( 'rest_url', $url, $path, $blog_id, $scheme );
+}
+
+/**
+ * Retrieves the URL to a REST endpoint.
+ *
+ * Note: The returned URL is NOT escaped.
+ *
+ * @since 4.4.0
+ *
+ * @param string $path   Optional. REST route. Default empty.
+ * @param string $scheme Optional. Sanitization scheme. Default 'rest'.
+ * @return string Full URL to the endpoint.
+ */
+function rest_url( $path = '', $scheme = 'rest' ) {
+	return get_rest_url( null, $path, $scheme );
+}
+
+/**
+ * Do a REST request.
+ *
+ * Used primarily to route internal requests through WP_REST_Server.
+ *
+ * @since 4.4.0
+ *
+ * @param WP_REST_Request|string $request Request.
+ * @return WP_REST_Response REST response.
+ */
+function rest_do_request( $request ) {
+	$request = rest_ensure_request( $request );
+	return rest_get_server()->dispatch( $request );
+}
+
+/**
+ * Retrieves the current REST server instance.
+ *
+ * Instantiates a new instance if none exists already.
+ *
+ * @since 4.5.0
+ *
+ * @global WP_REST_Server $wp_rest_server REST server instance.
+ *
+ * @return WP_REST_Server REST server instance.
+ */
+function rest_get_server() {
+	/* @var WP_REST_Server $wp_rest_server */
+	global $wp_rest_server;
+
+	if ( empty( $wp_rest_server ) ) {
+		/**
+		 * Filters the REST Server Class.
+		 *
+		 * This filter allows you to adjust the server class used by the API, using a
+		 * different class to handle requests.
+		 *
+		 * @since 4.4.0
+		 *
+		 * @param string $class_name The name of the server class. Default 'WP_REST_Server'.
+		 */
+		$wp_rest_server_class = apply_filters( 'wp_rest_server_class', 'WP_REST_Server' );
+		$wp_rest_server       = new $wp_rest_server_class;
+
+		/**
+		 * Fires when preparing to serve an API request.
+		 *
+		 * Endpoint objects should be created and register their hooks on this action rather
+		 * than another action to ensure they're only loaded when needed.
+		 *
+		 * @since 4.4.0
+		 *
+		 * @param WP_REST_Server $wp_rest_server Server object.
+		 */
+		do_action( 'rest_api_init', $wp_rest_server );
+	}
+
+	return $wp_rest_server;
+}
+
+/**
+ * Ensures request arguments are a request object (for consistency).
+ *
+ * @since 4.4.0
+ * @since 5.3.0 Accept string argument for the request path.
+ *
+ * @param array|string|WP_REST_Request $request Request to check.
+ * @return WP_REST_Request REST request instance.
+ */
+function rest_ensure_request( $request ) {
+	if ( $request instanceof WP_REST_Request ) {
+		return $request;
+	}
+
+	if ( is_string( $request ) ) {
+		return new WP_REST_Request( 'GET', $request );
+	}
+
+	return new WP_REST_Request( 'GET', '', $request );
+}
+
+/**
+ * Ensures a REST response is a response object (for consistency).
+ *
+ * This implements WP_HTTP_Response, allowing usage of `set_status`/`header`/etc
+ * without needing to double-check the object. Will also allow WP_Error to indicate error
+ * responses, so users should immediately check for this value.
+ *
+ * @since 4.4.0
+ *
+ * @param WP_Error|WP_HTTP_Response|mixed $response Response to check.
+ * @return WP_REST_Response|mixed If response generated an error, WP_Error, if response
+ *                                is already an instance, WP_HTTP_Response, otherwise
+ *                                returns a new WP_REST_Response instance.
+ */
+function rest_ensure_response( $response ) {
+	if ( is_wp_error( $response ) ) {
+		return $response;
+	}
+
+	if ( $response instanceof WP_HTTP_Response ) {
+		return $response;
+	}
+
+	return new WP_REST_Response( $response );
+}
+
+/**
+ * Handles _deprecated_function() errors.
+ *
+ * @since 4.4.0
+ *
+ * @param string $function    The function that was called.
+ * @param string $replacement The function that should have been called.
+ * @param string $version     Version.
+ */
+function rest_handle_deprecated_function( $function, $replacement, $version ) {
+	if ( ! WP_DEBUG || headers_sent() ) {
+		return;
+	}
+	if ( ! empty( $replacement ) ) {
+		/* translators: 1: Function name, 2: WordPress version number, 3: New function name. */
+		$string = sprintf( __( '%1$s (since %2$s; use %3$s instead)' ), $function, $version, $replacement );
+	} else {
+		/* translators: 1: Function name, 2: WordPress version number. */
+		$string = sprintf( __( '%1$s (since %2$s; no alternative available)' ), $function, $version );
+	}
+
+	header( sprintf( 'X-WP-DeprecatedFunction: %s', $string ) );
+}
+
+/**
+ * Handles _deprecated_argument() errors.
+ *
+ * @since 4.4.0
+ *
+ * @param string $function    The function that was called.
+ * @param string $message     A message regarding the change.
+ * @param string $version     Version.
+ */
+function rest_handle_deprecated_argument( $function, $message, $version ) {
+	if ( ! WP_DEBUG || headers_sent() ) {
+		return;
+	}
+	if ( ! empty( $message ) ) {
+		/* translators: 1: Function name, 2: WordPress version number, 3: Error message. */
+		$string = sprintf( __( '%1$s (since %2$s; %3$s)' ), $function, $version, $message );
+	} else {
+		/* translators: 1: Function name, 2: WordPress version number. */
+		$string = sprintf( __( '%1$s (since %2$s; no alternative available)' ), $function, $version );
+	}
+
+	header( sprintf( 'X-WP-DeprecatedParam: %s', $string ) );
+}
+
+/**
+ * Sends Cross-Origin Resource Sharing headers with API requests.
+ *
+ * @since 4.4.0
+ *
+ * @param mixed $value Response data.
+ * @return mixed Response data.
+ */
+function rest_send_cors_headers( $value ) {
+	$origin = get_http_origin();
+
+	if ( $origin ) {
+		// Requests from file:// and data: URLs send "Origin: null"
+		if ( 'null' !== $origin ) {
+			$origin = esc_url_raw( $origin );
+		}
+		header( 'Access-Control-Allow-Origin: ' . $origin );
+		header( 'Access-Control-Allow-Methods: OPTIONS, GET, POST, PUT, PATCH, DELETE' );
+		header( 'Access-Control-Allow-Credentials: true' );
+		header( 'Vary: Origin', false );
+	} elseif ( ! headers_sent() && 'GET' === $_SERVER['REQUEST_METHOD'] && ! is_user_logged_in() ) {
+		header( 'Vary: Origin', false );
+	}
+
+	return $value;
+}
+
+/**
+ * Handles OPTIONS requests for the server.
+ *
+ * This is handled outside of the server code, as it doesn't obey normal route
+ * mapping.
+ *
+ * @since 4.4.0
+ *
+ * @param mixed           $response Current response, either response or `null` to indicate pass-through.
+ * @param WP_REST_Server  $handler  ResponseHandler instance (usually WP_REST_Server).
+ * @param WP_REST_Request $request  The request that was used to make current response.
+ * @return WP_REST_Response Modified response, either response or `null` to indicate pass-through.
+ */
+function rest_handle_options_request( $response, $handler, $request ) {
+	if ( ! empty( $response ) || $request->get_method() !== 'OPTIONS' ) {
+		return $response;
+	}
+
+	$response = new WP_REST_Response();
+	$data     = array();
+
+	foreach ( $handler->get_routes() as $route => $endpoints ) {
+		$match = preg_match( '@^' . $route . '$@i', $request->get_route(), $matches );
+
+		if ( ! $match ) {
+			continue;
+		}
+
+		$args = array();
+		foreach ( $matches as $param => $value ) {
+			if ( ! is_int( $param ) ) {
+				$args[ $param ] = $value;
+			}
+		}
+
+		foreach ( $endpoints as $endpoint ) {
+			// Remove the redundant preg_match argument.
+			unset( $args[0] );
+
+			$request->set_url_params( $args );
+			$request->set_attributes( $endpoint );
+		}
+
+		$data = $handler->get_data_for_route( $route, $endpoints, 'help' );
+		$response->set_matched_route( $route );
+		break;
+	}
+
+	$response->set_data( $data );
+	return $response;
+}
+
+/**
+ * Sends the "Allow" header to state all methods that can be sent to the current route.
+ *
+ * @since 4.4.0
+ *
+ * @param WP_REST_Response $response Current response being served.
+ * @param WP_REST_Server   $server   ResponseHandler instance (usually WP_REST_Server).
+ * @param WP_REST_Request  $request  The request that was used to make current response.
+ * @return WP_REST_Response Response to be served, with "Allow" header if route has allowed methods.
+ */
+function rest_send_allow_header( $response, $server, $request ) {
+	$matched_route = $response->get_matched_route();
+
+	if ( ! $matched_route ) {
+		return $response;
+	}
+
+	$routes = $server->get_routes();
+
+	$allowed_methods = array();
+
+	// Get the allowed methods across the routes.
+	foreach ( $routes[ $matched_route ] as $_handler ) {
+		foreach ( $_handler['methods'] as $handler_method => $value ) {
+
+			if ( ! empty( $_handler['permission_callback'] ) ) {
+
+				$permission = call_user_func( $_handler['permission_callback'], $request );
+
+				$allowed_methods[ $handler_method ] = true === $permission;
+			} else {
+				$allowed_methods[ $handler_method ] = true;
+			}
+		}
+	}
+
+	// Strip out all the methods that are not allowed (false values).
+	$allowed_methods = array_filter( $allowed_methods );
+
+	if ( $allowed_methods ) {
+		$response->header( 'Allow', implode( ', ', array_map( 'strtoupper', array_keys( $allowed_methods ) ) ) );
+	}
+
+	return $response;
+}
+
+/**
+ * Recursively computes the intersection of arrays using keys for comparison.
+ *
+ * @param  array $array1 The array with master keys to check.
+ * @param  array $array2 An array to compare keys against.
+ *
+ * @return array An associative array containing all the entries of array1 which have keys that are present in all arguments.
+ */
+function _rest_array_intersect_key_recursive( $array1, $array2 ) {
+	$array1 = array_intersect_key( $array1, $array2 );
+	foreach ( $array1 as $key => $value ) {
+		if ( is_array( $value ) && is_array( $array2[ $key ] ) ) {
+			$array1[ $key ] = _rest_array_intersect_key_recursive( $value, $array2[ $key ] );
+		}
+	}
+	return $array1;
+}
+
+/**
+ * Filter the API response to include only a white-listed set of response object fields.
+ *
+ * @since 4.8.0
+ *
+ * @param WP_REST_Response $response Current response being served.
+ * @param WP_REST_Server   $server   ResponseHandler instance (usually WP_REST_Server).
+ * @param WP_REST_Request  $request  The request that was used to make current response.
+ *
+ * @return WP_REST_Response Response to be served, trimmed down to contain a subset of fields.
+ */
+function rest_filter_response_fields( $response, $server, $request ) {
+	if ( ! isset( $request['_fields'] ) || $response->is_error() ) {
+		return $response;
+	}
+
+	$data = $response->get_data();
+
+	$fields = wp_parse_list( $request['_fields'] );
+
+	if ( 0 === count( $fields ) ) {
+		return $response;
+	}
+
+	// Trim off outside whitespace from the comma delimited list.
+	$fields = array_map( 'trim', $fields );
+
+	// Create nested array of accepted field hierarchy.
+	$fields_as_keyed = array();
+	foreach ( $fields as $field ) {
+		$parts = explode( '.', $field );
+		$ref   = &$fields_as_keyed;
+		while ( count( $parts ) > 1 ) {
+			$next = array_shift( $parts );
+			if ( isset( $ref[ $next ] ) && true === $ref[ $next ] ) {
+				// Skip any sub-properties if their parent prop is already marked for inclusion.
+				break 2;
+			}
+			$ref[ $next ] = isset( $ref[ $next ] ) ? $ref[ $next ] : array();
+			$ref          = &$ref[ $next ];
+		}
+		$last         = array_shift( $parts );
+		$ref[ $last ] = true;
+	}
+
+	if ( wp_is_numeric_array( $data ) ) {
+		$new_data = array();
+		foreach ( $data as $item ) {
+			$new_data[] = _rest_array_intersect_key_recursive( $item, $fields_as_keyed );
+		}
+	} else {
+		$new_data = _rest_array_intersect_key_recursive( $data, $fields_as_keyed );
+	}
+
+	$response->set_data( $new_data );
+
+	return $response;
+}
+
+/**
+ * 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.
+ *
+ * If a parent field is passed in, the presence of any nested field within
+ * that parent will cause the method to return `true`. For example "title"
+ * will return true if any of `title`, `title.raw` or `title.rendered` is
+ * provided.
+ *
+ * @since 5.3.0
+ *
+ * @param string $field  A field to test for inclusion in the response body.
+ * @param array  $fields An array of string fields supported by the endpoint.
+ * @return bool Whether to include the field or not.
+ */
+function rest_is_field_included( $field, $fields ) {
+	if ( in_array( $field, $fields, true ) ) {
+		return true;
+	}
+	foreach ( $fields as $accepted_field ) {
+		// Check to see if $field is the parent of any item in $fields.
+		// A field "parent" should be accepted if "parent.child" is accepted.
+		if ( strpos( $accepted_field, "$field." ) === 0 ) {
+			return true;
+		}
+		// Conversely, if "parent" is accepted, all "parent.child" fields should
+		// also be accepted.
+		if ( strpos( $field, "$accepted_field." ) === 0 ) {
+			return true;
+		}
+	}
+	return false;
+}
+
+/**
+ * Adds the REST API URL to the WP RSD endpoint.
+ *
+ * @since 4.4.0
+ *
+ * @see get_rest_url()
+ */
+function rest_output_rsd() {
+	$api_root = get_rest_url();
+
+	if ( empty( $api_root ) ) {
+		return;
+	}
+	?>
+	<api name="WP-API" blogID="1" preferred="false" apiLink="<?php echo esc_url( $api_root ); ?>" />
+	<?php
+}
+
+/**
+ * Outputs the REST API link tag into page header.
+ *
+ * @since 4.4.0
+ *
+ * @see get_rest_url()
+ */
+function rest_output_link_wp_head() {
+	$api_root = get_rest_url();
+
+	if ( empty( $api_root ) ) {
+		return;
+	}
+
+	echo "<link rel='https://api.w.org/' href='" . esc_url( $api_root ) . "' />\n";
+}
+
+/**
+ * Sends a Link header for the REST API.
+ *
+ * @since 4.4.0
+ */
+function rest_output_link_header() {
+	if ( headers_sent() ) {
+		return;
+	}
+
+	$api_root = get_rest_url();
+
+	if ( empty( $api_root ) ) {
+		return;
+	}
+
+	header( 'Link: <' . esc_url_raw( $api_root ) . '>; rel="https://api.w.org/"', false );
+}
+
+/**
+ * Checks for errors when using cookie-based authentication.
+ *
+ * WordPress' built-in cookie authentication is always active
+ * for logged in users. However, the API has to check nonces
+ * for each request to ensure users are not vulnerable to CSRF.
+ *
+ * @since 4.4.0
+ *
+ * @global mixed          $wp_rest_auth_cookie
+ *
+ * @param WP_Error|mixed $result Error from another authentication handler,
+ *                               null if we should handle it, or another value
+ *                               if not.
+ * @return WP_Error|mixed|bool WP_Error if the cookie is invalid, the $result, otherwise true.
+ */
+function rest_cookie_check_errors( $result ) {
+	if ( ! empty( $result ) ) {
+		return $result;
+	}
+
+	global $wp_rest_auth_cookie;
+
+	/*
+	 * Is cookie authentication being used? (If we get an auth
+	 * error, but we're still logged in, another authentication
+	 * must have been used).
+	 */
+	if ( true !== $wp_rest_auth_cookie && is_user_logged_in() ) {
+		return $result;
+	}
+
+	// Determine if there is a nonce.
+	$nonce = null;
+
+	if ( isset( $_REQUEST['_wpnonce'] ) ) {
+		$nonce = $_REQUEST['_wpnonce'];
+	} elseif ( isset( $_SERVER['HTTP_X_WP_NONCE'] ) ) {
+		$nonce = $_SERVER['HTTP_X_WP_NONCE'];
+	}
+
+	if ( null === $nonce ) {
+		// No nonce at all, so act as if it's an unauthenticated request.
+		wp_set_current_user( 0 );
+		return true;
+	}
+
+	// Check the nonce.
+	$result = wp_verify_nonce( $nonce, 'wp_rest' );
+
+	if ( ! $result ) {
+		return new WP_Error( 'rest_cookie_invalid_nonce', __( 'Cookie nonce is invalid' ), array( 'status' => 403 ) );
+	}
+
+	// Send a refreshed nonce in header.
+	rest_get_server()->send_header( 'X-WP-Nonce', wp_create_nonce( 'wp_rest' ) );
+
+	return true;
+}
+
+/**
+ * Collects cookie authentication status.
+ *
+ * Collects errors from wp_validate_auth_cookie for use by rest_cookie_check_errors.
+ *
+ * @since 4.4.0
+ *
+ * @see current_action()
+ * @global mixed $wp_rest_auth_cookie
+ */
+function rest_cookie_collect_status() {
+	global $wp_rest_auth_cookie;
+
+	$status_type = current_action();
+
+	if ( 'auth_cookie_valid' !== $status_type ) {
+		$wp_rest_auth_cookie = substr( $status_type, 12 );
+		return;
+	}
+
+	$wp_rest_auth_cookie = true;
+}
+
+/**
+ * Parses an RFC3339 time into a Unix timestamp.
+ *
+ * @since 4.4.0
+ *
+ * @param string $date      RFC3339 timestamp.
+ * @param bool   $force_utc Optional. Whether to force UTC timezone instead of using
+ *                          the timestamp's timezone. Default false.
+ * @return int Unix timestamp.
+ */
+function rest_parse_date( $date, $force_utc = false ) {
+	if ( $force_utc ) {
+		$date = preg_replace( '/[+-]\d+:?\d+$/', '+00:00', $date );
+	}
+
+	$regex = '#^\d{4}-\d{2}-\d{2}[Tt ]\d{2}:\d{2}:\d{2}(?:\.\d+)?(?:Z|[+-]\d{2}(?::\d{2})?)?$#';
+
+	if ( ! preg_match( $regex, $date, $matches ) ) {
+		return false;
+	}
+
+	return strtotime( $date );
+}
+
+/**
+ * Parses a date into both its local and UTC equivalent, in MySQL datetime format.
+ *
+ * @since 4.4.0
+ *
+ * @see rest_parse_date()
+ *
+ * @param string $date   RFC3339 timestamp.
+ * @param bool   $is_utc Whether the provided date should be interpreted as UTC. Default false.
+ * @return array|null Local and UTC datetime strings, in MySQL datetime format (Y-m-d H:i:s),
+ *                    null on failure.
+ */
+function rest_get_date_with_gmt( $date, $is_utc = false ) {
+	// Whether or not the original date actually has a timezone string
+	// changes the way we need to do timezone conversion.  Store this info
+	// before parsing the date, and use it later.
+	$has_timezone = preg_match( '#(Z|[+-]\d{2}(:\d{2})?)$#', $date );
+
+	$date = rest_parse_date( $date );
+
+	if ( empty( $date ) ) {
+		return null;
+	}
+
+	// At this point $date could either be a local date (if we were passed a
+	// *local* date without a timezone offset) or a UTC date (otherwise).
+	// Timezone conversion needs to be handled differently between these two
+	// cases.
+	if ( ! $is_utc && ! $has_timezone ) {
+		$local = gmdate( 'Y-m-d H:i:s', $date );
+		$utc   = get_gmt_from_date( $local );
+	} else {
+		$utc   = gmdate( 'Y-m-d H:i:s', $date );
+		$local = get_date_from_gmt( $utc );
+	}
+
+	return array( $local, $utc );
+}
+
+/**
+ * Returns a contextual HTTP error code for authorization failure.
+ *
+ * @since 4.7.0
+ *
+ * @return integer 401 if the user is not logged in, 403 if the user is logged in.
+ */
+function rest_authorization_required_code() {
+	return is_user_logged_in() ? 403 : 401;
+}
+
+/**
+ * Validate a request argument based on details registered to the route.
+ *
+ * @since 4.7.0
+ *
+ * @param  mixed            $value
+ * @param  WP_REST_Request  $request
+ * @param  string           $param
+ * @return WP_Error|boolean
+ */
+function rest_validate_request_arg( $value, $request, $param ) {
+	$attributes = $request->get_attributes();
+	if ( ! isset( $attributes['args'][ $param ] ) || ! is_array( $attributes['args'][ $param ] ) ) {
+		return true;
+	}
+	$args = $attributes['args'][ $param ];
+
+	return rest_validate_value_from_schema( $value, $args, $param );
+}
+
+/**
+ * Sanitize a request argument based on details registered to the route.
+ *
+ * @since 4.7.0
+ *
+ * @param  mixed            $value
+ * @param  WP_REST_Request  $request
+ * @param  string           $param
+ * @return mixed
+ */
+function rest_sanitize_request_arg( $value, $request, $param ) {
+	$attributes = $request->get_attributes();
+	if ( ! isset( $attributes['args'][ $param ] ) || ! is_array( $attributes['args'][ $param ] ) ) {
+		return $value;
+	}
+	$args = $attributes['args'][ $param ];
+
+	return rest_sanitize_value_from_schema( $value, $args );
+}
+
+/**
+ * Parse a request argument based on details registered to the route.
+ *
+ * Runs a validation check and sanitizes the value, primarily to be used via
+ * the `sanitize_callback` arguments in the endpoint args registration.
+ *
+ * @since 4.7.0
+ *
+ * @param  mixed            $value
+ * @param  WP_REST_Request  $request
+ * @param  string           $param
+ * @return mixed
+ */
+function rest_parse_request_arg( $value, $request, $param ) {
+	$is_valid = rest_validate_request_arg( $value, $request, $param );
+
+	if ( is_wp_error( $is_valid ) ) {
+		return $is_valid;
+	}
+
+	$value = rest_sanitize_request_arg( $value, $request, $param );
+
+	return $value;
+}
+
+/**
+ * Determines if an IP address is valid.
+ *
+ * Handles both IPv4 and IPv6 addresses.
+ *
+ * @since 4.7.0
+ *
+ * @param  string $ip IP address.
+ * @return string|false The valid IP address, otherwise false.
+ */
+function rest_is_ip_address( $ip ) {
+	$ipv4_pattern = '/^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$/';
+
+	if ( ! preg_match( $ipv4_pattern, $ip ) && ! Requests_IPv6::check_ipv6( $ip ) ) {
+		return false;
+	}
+
+	return $ip;
+}
+
+/**
+ * Changes a boolean-like value into the proper boolean value.
+ *
+ * @since 4.7.0
+ *
+ * @param bool|string|int $value The value being evaluated.
+ * @return boolean Returns the proper associated boolean value.
+ */
+function rest_sanitize_boolean( $value ) {
+	// String values are translated to `true`; make sure 'false' is false.
+	if ( is_string( $value ) ) {
+		$value = strtolower( $value );
+		if ( in_array( $value, array( 'false', '0' ), true ) ) {
+			$value = false;
+		}
+	}
+
+	// Everything else will map nicely to boolean.
+	return (bool) $value;
+}
+
+/**
+ * Determines if a given value is boolean-like.
+ *
+ * @since 4.7.0
+ *
+ * @param bool|string $maybe_bool The value being evaluated.
+ * @return boolean True if a boolean, otherwise false.
+ */
+function rest_is_boolean( $maybe_bool ) {
+	if ( is_bool( $maybe_bool ) ) {
+		return true;
+	}
+
+	if ( is_string( $maybe_bool ) ) {
+		$maybe_bool = strtolower( $maybe_bool );
+
+		$valid_boolean_values = array(
+			'false',
+			'true',
+			'0',
+			'1',
+		);
+
+		return in_array( $maybe_bool, $valid_boolean_values, true );
+	}
+
+	if ( is_int( $maybe_bool ) ) {
+		return in_array( $maybe_bool, array( 0, 1 ), true );
+	}
+
+	return false;
+}
+
+/**
+ * Retrieves the avatar urls in various sizes.
+ *
+ * @since 4.7.0
+ *
+ * @see get_avatar_url()
+ *
+ * @param mixed $id_or_email The Gravatar to retrieve a URL for. Accepts a user_id, gravatar md5 hash,
+ *                           user email, WP_User object, WP_Post object, or WP_Comment object.
+ * @return array $urls Gravatar url for each size.
+ */
+function rest_get_avatar_urls( $id_or_email ) {
+	$avatar_sizes = rest_get_avatar_sizes();
+
+	$urls = array();
+	foreach ( $avatar_sizes as $size ) {
+		$urls[ $size ] = get_avatar_url( $id_or_email, array( 'size' => $size ) );
+	}
+
+	return $urls;
+}
+
+/**
+ * Retrieves the pixel sizes for avatars.
+ *
+ * @since 4.7.0
+ *
+ * @return array List of pixel sizes for avatars. Default `[ 24, 48, 96 ]`.
+ */
+function rest_get_avatar_sizes() {
+	/**
+	 * Filters the REST avatar sizes.
+	 *
+	 * Use this filter to adjust the array of sizes returned by the
+	 * `rest_get_avatar_sizes` function.
+	 *
+	 * @since 4.4.0
+	 *
+	 * @param array $sizes An array of int values that are the pixel sizes for avatars.
+	 *                     Default `[ 24, 48, 96 ]`.
+	 */
+	return apply_filters( 'rest_avatar_sizes', array( 24, 48, 96 ) );
+}
+
+/**
+ * Validate a value based on a schema.
+ *
+ * @since 4.7.0
+ *
+ * @param mixed  $value The value to validate.
+ * @param array  $args  Schema array to use for validation.
+ * @param string $param The parameter name, used in error messages.
+ * @return true|WP_Error
+ */
+function rest_validate_value_from_schema( $value, $args, $param = '' ) {
+	if ( is_array( $args['type'] ) ) {
+		foreach ( $args['type'] as $type ) {
+			$type_args         = $args;
+			$type_args['type'] = $type;
+
+			if ( true === rest_validate_value_from_schema( $value, $type_args, $param ) ) {
+				return true;
+			}
+		}
+
+		/* translators: 1: Parameter, 2: List of types. */
+		return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s is not of type %2$s' ), $param, implode( ',', $args['type'] ) ) );
+	}
+
+	if ( 'array' === $args['type'] ) {
+		if ( ! is_null( $value ) ) {
+			$value = wp_parse_list( $value );
+		}
+		if ( ! wp_is_numeric_array( $value ) ) {
+			/* translators: 1: Parameter, 2: Type name. */
+			return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s is not of type %2$s.' ), $param, 'array' ) );
+		}
+		foreach ( $value as $index => $v ) {
+			$is_valid = rest_validate_value_from_schema( $v, $args['items'], $param . '[' . $index . ']' );
+			if ( is_wp_error( $is_valid ) ) {
+				return $is_valid;
+			}
+		}
+	}
+
+	if ( 'object' === $args['type'] ) {
+		if ( $value instanceof stdClass ) {
+			$value = (array) $value;
+		}
+
+		if ( $value instanceof JsonSerializable ) {
+			$value = $value->jsonSerialize();
+		}
+
+		if ( ! is_array( $value ) ) {
+			/* translators: 1: Parameter, 2: Type name. */
+			return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s is not of type %2$s.' ), $param, 'object' ) );
+		}
+
+		foreach ( $value as $property => $v ) {
+			if ( isset( $args['properties'][ $property ] ) ) {
+				$is_valid = rest_validate_value_from_schema( $v, $args['properties'][ $property ], $param . '[' . $property . ']' );
+				if ( is_wp_error( $is_valid ) ) {
+					return $is_valid;
+				}
+			} elseif ( isset( $args['additionalProperties'] ) ) {
+				if ( false === $args['additionalProperties'] ) {
+					/* translators: %s: Property of an object. */
+					return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s is not a valid property of Object.' ), $property ) );
+				}
+
+				if ( is_array( $args['additionalProperties'] ) ) {
+					$is_valid = rest_validate_value_from_schema( $v, $args['additionalProperties'], $param . '[' . $property . ']' );
+					if ( is_wp_error( $is_valid ) ) {
+						return $is_valid;
+					}
+				}
+			}
+		}
+	}
+
+	if ( 'null' === $args['type'] ) {
+		if ( null !== $value ) {
+			/* translators: 1: Parameter, 2: Type name. */
+			return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s is not of type %2$s.' ), $param, 'null' ) );
+		}
+
+		return true;
+	}
+
+	if ( ! empty( $args['enum'] ) ) {
+		if ( ! in_array( $value, $args['enum'], true ) ) {
+			/* translators: 1: Parameter, 2: List of valid values. */
+			return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s is not one of %2$s.' ), $param, implode( ', ', $args['enum'] ) ) );
+		}
+	}
+
+	if ( in_array( $args['type'], array( 'integer', 'number' ) ) && ! is_numeric( $value ) ) {
+		/* translators: 1: Parameter, 2: Type name. */
+		return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s is not of type %2$s.' ), $param, $args['type'] ) );
+	}
+
+	if ( 'integer' === $args['type'] && round( floatval( $value ) ) !== floatval( $value ) ) {
+		/* translators: 1: Parameter, 2: Type name. */
+		return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s is not of type %2$s.' ), $param, 'integer' ) );
+	}
+
+	if ( 'boolean' === $args['type'] && ! rest_is_boolean( $value ) ) {
+		/* translators: 1: Parameter, 2: Type name. */
+		return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s is not of type %2$s.' ), $param, 'boolean' ) );
+	}
+
+	if ( 'string' === $args['type'] && ! is_string( $value ) ) {
+		/* translators: 1: Parameter, 2: Type name. */
+		return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s is not of type %2$s.' ), $param, 'string' ) );
+	}
+
+	if ( isset( $args['format'] ) ) {
+		switch ( $args['format'] ) {
+			case 'date-time':
+				if ( ! rest_parse_date( $value ) ) {
+					return new WP_Error( 'rest_invalid_date', __( 'Invalid date.' ) );
+				}
+				break;
+
+			case 'email':
+				if ( ! is_email( $value ) ) {
+					return new WP_Error( 'rest_invalid_email', __( 'Invalid email address.' ) );
+				}
+				break;
+			case 'ip':
+				if ( ! rest_is_ip_address( $value ) ) {
+					/* translators: %s: IP address. */
+					return new WP_Error( 'rest_invalid_param', sprintf( __( '%s is not a valid IP address.' ), $param ) );
+				}
+				break;
+		}
+	}
+
+	if ( in_array( $args['type'], array( 'number', 'integer' ), true ) && ( isset( $args['minimum'] ) || isset( $args['maximum'] ) ) ) {
+		if ( isset( $args['minimum'] ) && ! isset( $args['maximum'] ) ) {
+			if ( ! empty( $args['exclusiveMinimum'] ) && $value <= $args['minimum'] ) {
+				/* translators: 1: Parameter, 2: Minimum number. */
+				return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s must be greater than %2$d' ), $param, $args['minimum'] ) );
+			} elseif ( empty( $args['exclusiveMinimum'] ) && $value < $args['minimum'] ) {
+				/* translators: 1: Parameter, 2: Minimum number. */
+				return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s must be greater than or equal to %2$d' ), $param, $args['minimum'] ) );
+			}
+		} elseif ( isset( $args['maximum'] ) && ! isset( $args['minimum'] ) ) {
+			if ( ! empty( $args['exclusiveMaximum'] ) && $value >= $args['maximum'] ) {
+				/* translators: 1: Parameter, 2: Maximum number. */
+				return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s must be less than %2$d' ), $param, $args['maximum'] ) );
+			} elseif ( empty( $args['exclusiveMaximum'] ) && $value > $args['maximum'] ) {
+				/* translators: 1: Parameter, 2: Maximum number. */
+				return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s must be less than or equal to %2$d' ), $param, $args['maximum'] ) );
+			}
+		} elseif ( isset( $args['maximum'] ) && isset( $args['minimum'] ) ) {
+			if ( ! empty( $args['exclusiveMinimum'] ) && ! empty( $args['exclusiveMaximum'] ) ) {
+				if ( $value >= $args['maximum'] || $value <= $args['minimum'] ) {
+					/* translators: 1: Parameter, 2: Minimum number, 3: Maximum number. */
+					return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s must be between %2$d (exclusive) and %3$d (exclusive)' ), $param, $args['minimum'], $args['maximum'] ) );
+				}
+			} elseif ( empty( $args['exclusiveMinimum'] ) && ! empty( $args['exclusiveMaximum'] ) ) {
+				if ( $value >= $args['maximum'] || $value < $args['minimum'] ) {
+					/* translators: 1: Parameter, 2: Minimum number, 3: Maximum number. */
+					return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s must be between %2$d (inclusive) and %3$d (exclusive)' ), $param, $args['minimum'], $args['maximum'] ) );
+				}
+			} elseif ( ! empty( $args['exclusiveMinimum'] ) && empty( $args['exclusiveMaximum'] ) ) {
+				if ( $value > $args['maximum'] || $value <= $args['minimum'] ) {
+					/* translators: 1: Parameter, 2: Minimum number, 3: Maximum number. */
+					return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s must be between %2$d (exclusive) and %3$d (inclusive)' ), $param, $args['minimum'], $args['maximum'] ) );
+				}
+			} elseif ( empty( $args['exclusiveMinimum'] ) && empty( $args['exclusiveMaximum'] ) ) {
+				if ( $value > $args['maximum'] || $value < $args['minimum'] ) {
+					/* translators: 1: Parameter, 2: Minimum number, 3: Maximum number. */
+					return new WP_Error( 'rest_invalid_param', sprintf( __( '%1$s must be between %2$d (inclusive) and %3$d (inclusive)' ), $param, $args['minimum'], $args['maximum'] ) );
+				}
+			}
+		}
+	}
+
+	return true;
+}
+
+/**
+ * Sanitize a value based on a schema.
+ *
+ * @since 4.7.0
+ *
+ * @param mixed $value The value to sanitize.
+ * @param array $args  Schema array to use for sanitization.
+ * @return true|WP_Error
+ */
+function rest_sanitize_value_from_schema( $value, $args ) {
+	if ( is_array( $args['type'] ) ) {
+		// Determine which type the value was validated against, and use that type when performing sanitization
+		$validated_type = '';
+
+		foreach ( $args['type'] as $type ) {
+			$type_args         = $args;
+			$type_args['type'] = $type;
+
+			if ( ! is_wp_error( rest_validate_value_from_schema( $value, $type_args ) ) ) {
+				$validated_type = $type;
+				break;
+			}
+		}
+
+		if ( ! $validated_type ) {
+			return null;
+		}
+
+		$args['type'] = $validated_type;
+	}
+
+	if ( 'array' === $args['type'] ) {
+		if ( empty( $args['items'] ) ) {
+			return (array) $value;
+		}
+		$value = wp_parse_list( $value );
+		foreach ( $value as $index => $v ) {
+			$value[ $index ] = rest_sanitize_value_from_schema( $v, $args['items'] );
+		}
+		// Normalize to numeric array so nothing unexpected
+		// is in the keys.
+		$value = array_values( $value );
+		return $value;
+	}
+
+	if ( 'object' === $args['type'] ) {
+		if ( $value instanceof stdClass ) {
+			$value = (array) $value;
+		}
+
+		if ( $value instanceof JsonSerializable ) {
+			$value = $value->jsonSerialize();
+		}
+
+		if ( ! is_array( $value ) ) {
+			return array();
+		}
+
+		foreach ( $value as $property => $v ) {
+			if ( isset( $args['properties'][ $property ] ) ) {
+				$value[ $property ] = rest_sanitize_value_from_schema( $v, $args['properties'][ $property ] );
+			} elseif ( isset( $args['additionalProperties'] ) ) {
+				if ( false === $args['additionalProperties'] ) {
+					unset( $value[ $property ] );
+				} elseif ( is_array( $args['additionalProperties'] ) ) {
+					$value[ $property ] = rest_sanitize_value_from_schema( $v, $args['additionalProperties'] );
+				}
+			}
+		}
+
+		return $value;
+	}
+
+	if ( 'null' === $args['type'] ) {
+		return null;
+	}
+
+	if ( 'integer' === $args['type'] ) {
+		return (int) $value;
+	}
+
+	if ( 'number' === $args['type'] ) {
+		return (float) $value;
+	}
+
+	if ( 'boolean' === $args['type'] ) {
+		return rest_sanitize_boolean( $value );
+	}
+
+	if ( isset( $args['format'] ) ) {
+		switch ( $args['format'] ) {
+			case 'date-time':
+				return sanitize_text_field( $value );
+
+			case 'email':
+				/*
+				 * sanitize_email() validates, which would be unexpected.
+				 */
+				return sanitize_text_field( $value );
+
+			case 'uri':
+				return esc_url_raw( $value );
+
+			case 'ip':
+				return sanitize_text_field( $value );
+		}
+	}
+
+	if ( 'string' === $args['type'] ) {
+		return strval( $value );
+	}
+
+	return $value;
+}
+
+/**
+ * Append result of internal request to REST API for purpose of preloading data to be attached to a page.
+ * Expected to be called in the context of `array_reduce`.
+ *
+ * @since 5.0.0
+ *
+ * @param  array  $memo Reduce accumulator.
+ * @param  string $path REST API path to preload.
+ * @return array        Modified reduce accumulator.
+ */
+function rest_preload_api_request( $memo, $path ) {
+	// array_reduce() doesn't support passing an array in PHP 5.2, so we need to make sure we start with one.
+	if ( ! is_array( $memo ) ) {
+		$memo = array();
+	}
+
+	if ( empty( $path ) ) {
+		return $memo;
+	}
+
+	$method = 'GET';
+	if ( is_array( $path ) && 2 === count( $path ) ) {
+		$method = end( $path );
+		$path   = reset( $path );
+
+		if ( ! in_array( $method, array( 'GET', 'OPTIONS' ), true ) ) {
+			$method = 'GET';
+		}
+	}
+
+	$path_parts = parse_url( $path );
+	if ( false === $path_parts ) {
+		return $memo;
+	}
+
+	$request = new WP_REST_Request( $method, $path_parts['path'] );
+	if ( ! empty( $path_parts['query'] ) ) {
+		parse_str( $path_parts['query'], $query_params );
+		$request->set_query_params( $query_params );
+	}
+
+	$response = rest_do_request( $request );
+	if ( 200 === $response->status ) {
+		$server = rest_get_server();
+		$data   = (array) $response->get_data();
+		$links  = $server::get_compact_response_links( $response );
+		if ( ! empty( $links ) ) {
+			$data['_links'] = $links;
+		}
+
+		if ( 'OPTIONS' === $method ) {
+			$response = rest_send_allow_header( $response, $server, $request );
+
+			$memo[ $method ][ $path ] = array(
+				'body'    => $data,
+				'headers' => $response->headers,
+			);
+		} else {
+			$memo[ $path ] = array(
+				'body'    => $data,
+				'headers' => $response->headers,
+			);
+		}
+	}
+
+	return $memo;
+}