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action is not described

rest_insert_attachment action-hook . WP 4.7.0

Fires after a single attachment is created or updated via the REST API.

Usage

add_action( 'rest_insert_attachment', 'action_function_name_9094', 10, 3 );
function action_function_name_9094( $attachment, $request, $creating ){
	// action...
}
$attachment(WP_Post)
Inserted or updated attachment object.
$request(WP_REST_Request)
The request sent to the API.
$creating(true/false)
True when creating an attachment, false when updating.

Where the hook is called

WP_REST_Attachments_Controller::create_item()
wp-includes/rest-api/endpoints/class-wp-rest-attachments-controller.php 173
do_action( 'rest_insert_attachment', $attachment, $request, true );

Where the hook is used (in WP core)

Does not used.