WordPress at a glance
filter is not described

rest_pre_echo_response filter-hook . WP 4.8.1

Filters the API response.

Allows modification of the response data after inserting embedded data (if any) and before echoing the response data.

Usage

add_filter( 'rest_pre_echo_response', 'filter_function_name_7408', 10, 3 );
function filter_function_name_7408( $result, $this, $request ){
	// filter...

	return $result;
}
$result(array)
Response data to send to the client.
$this(WP_REST_Server)
Server instance.
$request(WP_REST_Request)
Request used to generate the response.

Where the hook is called

WP_REST_Server::serve_request()
wp-includes/rest-api/class-wp-rest-server.php 394
$result = apply_filters( 'rest_pre_echo_response', $result, $this, $request );

Where the hook is used (in WP core)

Does not used.