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rest_pre_dispatch filter-hook . WP 4.4.0

Filters the pre-calculated result of a REST dispatch request.

Allow hijacking the request before dispatching by returning a non-empty. The returned value will be used to serve the request instead.

Usage

add_filter( 'rest_pre_dispatch', 'filter_function_name_2804', 10, 3 );
function filter_function_name_2804( $result, $this, $request ){
	// filter...

	return $result;
}
$result(mixed)
Response to replace the requested version with. Can be anything a normal endpoint can return, or null to not hijack the request.
$this(WP_REST_Server)
Server instance.
$request(WP_REST_Request)
Request used to generate the response.

Where the hook is called

WP_REST_Server::dispatch()
wp-includes/rest-api/class-wp-rest-server.php 817
$result = apply_filters( 'rest_pre_dispatch', null, $this, $request );

Where the hook is used (in WP core)

wp-includes/rest-api.php 170
add_filter( 'rest_pre_dispatch', 'rest_handle_options_request', 10, 3 );