"""
        A restful endpoint that returns external links for a given Operator.
        It queries the operator that sent the request for the links it wishes
        to provide for a given external link name.
        API: GET
        Args: dag_id: The id of the dag containing the task in question
              task_id: The id of the task in question
              execution_date: The date of execution of the task
              link_name: The name of the link reference to find the actual URL for
        Returns:
            200: {url: <url of link>, error: None} - returned when there was no problem
                finding the URL
            404: {url: None, error: <error message>} - returned when the operator does
                not return a URL
        """
        dag_id = request.args.get("dag_id")
        task_id = request.args.get("task_id")
        map_index = request.args.get("map_index", -1, type=int)
        execution_date = request.args.get("execution_date")
        dttm = _safe_parse_datetime(execution_date)
        dag = get_airflow_app().dag_bag.get_dag(dag_id)
        if not dag or task_id not in dag.task_ids:
            return {"url": None, "error": f"can't find dag {dag} or task_id {task_id}"}, 404
        task: AbstractOperator = dag.get_task(task_id)
        link_name = request.args.get("link_name")