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filter is not described

rest_(taxonomy)_query filter-hook . WP 4.7.0

Filters the query arguments before passing them to get_terms().

The dynamic portion of the hook name, $this->taxonomy, refers to the taxonomy slug.

Enables adding extra arguments or setting defaults for a terms collection request.

Usage

add_filter( 'rest_(taxonomy)_query', 'filter_function_name_8808', 10, 2 );
function filter_function_name_8808( $prepared_args, $request ){
	// filter...

	return $prepared_args;
}
$prepared_args(array)
Array of arguments to be passed to get_terms().
$request(WP_REST_Request)
The current request.

Where the hook is called

WP_REST_Terms_Controller::get_items()
wp-includes/rest-api/endpoints/class-wp-rest-terms-controller.php 236
$prepared_args = apply_filters( "rest_{$this->taxonomy}_query", $prepared_args, $request );

Where the hook is used (in WP core)

Does not used.