Maciej Bukczynski
08/04/2025, 11:47 PM@task
in a prefect worker outside of a @flow
(like the https://docs-3.prefect.io/v3/advanced/background-tasks pattern), will it get logged anywhere in the prefect cloud ui or no?Marvin
08/04/2025, 11:47 PMMarvin
08/04/2025, 11:48 PM@task
decorated functions outside of flows:
No, tasks run outside of a flow context will not automatically get logged in the Prefect Cloud UI. This is because tasks need the flow context to properly hook into Prefect's observability and logging infrastructure.
Here are your options if you want to run tasks in the background but still maintain observability:
1. Recommended Approach: Create a minimal flow that wraps your background task:
python
from prefect import flow, task
@task
def my_background_task():
# Your task logic here
pass
@flow
def background_wrapper():
return my_background_task()
# Then run it as:
background_wrapper()
2. If you absolutely must run the task directly (not recommended), you can use log_prints=True
in your task decorator to at least capture print statements:
python
@task(log_prints=True)
def my_task():
print("This will be captured")
However, this won't give you the full task run tracking and state management you'd get within a flow.
The key thing to understand is that Prefect's orchestration features (including UI logging, state tracking, and retries) are fundamentally built around the flow context. Running tasks outside of flows means you lose these benefits.
If you're implementing background tasks, I'd recommend checking out the complete pattern in the background tasks documentation which shows how to properly structure this while maintaining observability.Maciej Bukczynski
08/04/2025, 11:50 PMMarvin
08/04/2025, 11:50 PMexplore_module_offerings
📊 Tools used:
• explore_module_offerings
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• review_common_3x_gotchas
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• search_prefect_3x_docs
(12x)Marvin
08/04/2025, 11:51 PMMarvin
08/04/2025, 11:52 PMpython
from prefect import task, serve
from prefect.worker import Worker
@task
def my_background_task():
# do something
pass
if __name__ == "__main__":
worker = Worker(pool_name="my-pool")
serve(worker)
And then using it like:
python
future = my_background_task.submit()
I apologize, but I now realize I can't definitively say whether these background tasks show up in the UI or not based on the available documentation and research. This seems to be a gap in the documentation.
Would you like me to:
1. Research a specific aspect of this further?
2. Look for alternative patterns that would definitely give you the observability you're looking for?
The safest way to ensure task observability would be to wrap the task in a flow as mentioned earlier, but I understand that might not meet your background task needs. Let me know what aspect you'd like me to clarify further.Nate
08/05/2025, 1:31 AMNate
08/05/2025, 1:32 AMNate
08/05/2025, 1:32 AM