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apply_filters( 'rest_request_before_callbacks', WP_REST_Response|WP_HTTP_Response|WP_Error|mixed $response, array $handler, WP_REST_Request $request )

Filters the response before executing any REST API callbacks.

Allows plugins to perform additional validation after a request is initialized and matched to a registered route, but before it is executed.

Note that this filter will not be called for requests that fail to authenticate or match to a registered route.

$response: (WP_REST_Response|WP_HTTP_Response|WP_Error|mixed) Result to send to the client. Usually a WP_REST_Response or WP_Error.
$handler: (array) Route handler used for the request.
$request: (WP_REST_Request) Request used to generate the response.

Used By	Description
wp-includes/rest-api/class-wp-rest-server.php: WP_REST_Server::dispatch()	Matches the request to a callback and call it.

Version	Description
4.7.0	Introduced.