Anton Chekmarev

09/02/2021, 12:06 PM
Hello everyone, I am looking for a way to make my flow dependent on another one. In Airflow I used externalTaskSensor: in DAG "B" check DAG "A" status, if it's not a success then retry later. I've tried StartFlowRun, but it starts a new run of DAG "A" every time. I have some heavy computation in "A" and don't want it to be run multiple times. Is there a way to do it without kicking off parent flow?
👀 1

Kevin Kho

09/02/2021, 1:57 PM
Hey @Anton Chekmarev, we don’t have sensors in Prefect. We use event driven flows instead. So if there is an upstream flow or event, you can use
or hit the API when that event happens to trigger a flow run. Some people add a loop inside their task to check for the completion of the upstream task.