My flow A has a StartFlowRun task that runs flow B...
# ask-communitym
Matthew Seligson
02/04/2022, 6:41 PMMy flow A has a StartFlowRun task that runs flow B. If I’m looking at a flow run of flow A in the UI, how can I navigate to the corresponding run of flow B?
a
Anna Geller
02/04/2022, 6:51 PM
There is not a straightforward way to do it in Prefect 1.0. One way to navigate to a child flow run is through logs: within your parent flow run logs, you should see something like this:
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Flow run created: <https://cloud.prefect.io/anna-prefect/flow-run/d3f27dd8-1e5e-40af-94cf-46766ef080f3>Anna Geller
02/04/2022, 6:53 PM
What you can also do is adding stream_logs=True to see child flow run logs directly in the parent flow run logs.
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from prefect import Flow
from prefect.tasks.prefect import create_flow_run, wait_for_flow_run
with Flow("parent_flow") as flow:
child_flow_run_id = create_flow_run(
flow_name="child_flow_name", run_name="custom_run_name"
)
child_flowrunview = wait_for_flow_run(
child_flow_run_id, raise_final_state=True, stream_logs=True
)m
Matthew Seligson
02/04/2022, 7:16 PMCan I only wait for my subflow to complete in Orion?
k
Kevin Kho
02/04/2022, 7:29 PM
You mean subflow in Orion but main flow in current Prefect?
a
Anna Geller
02/04/2022, 8:31 PM
When using the default SequentialTaskRunner, Orion actually waits till your child flow run completes before starting any downstream tasks/subflows, try this example:
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from prefect import flow
import time
@flow
def subflow(x):
print("I am a subflow - waiting for 5 seconds to show some processing!")
time.sleep(5)
return x
@flow
def second_subflow(x):
print("I am a second subflow!")
return x
@flow
def main_flow():
data = subflow(5)
second_subflow(data)
if __name__ == "__main__":
main_flow()23 Views