src/Ajaxer.php
protected function trigger_ajax_callback( $action ) {
		$_function_action = $this->extract_action_slug( $action );
		if ( method_exists( $this, $this->function_name( $_function_action ) ) ) {
			$function = $this->function_name( $_function_action );
			\do_action( 'ajax_before_' . $action );
			$this->$function();
			\do_action( 'ajax_after_' . $action );
		} else {
			\do_action( 'ajax_' . $action );
		}
	}
protected function trigger_ajax_callback( $action ) {
		$_function_action = $this->extract_action_slug( $action );
		if ( method_exists( $this, $this->function_name( $_function_action ) ) ) {
			$function = $this->function_name( $_function_action );
			\do_action( 'ajax_before_' . $action );
			$this->$function();
			\do_action( 'ajax_after_' . $action );
		} else {
			\do_action( 'ajax_' . $action );
		}
	}
Triggers A AjaxCallback

@hook ajax_before_{ajax_action}
@hook ajax_after_{ajax_action}
if method not exists then below hook fires
@hook ajax_{ajax_action}

@param $action