Hi all, I have a Python task in my flow that has sys.exit() in it meaning I want that task to break if some condition has met and do not proceed further. But, my task keeps on running in this case and does nothing. Any help?

You should be able to use something like

from prefect.engine.signals import FAIL
from prefect import task

@task
def my_task():
   if condition:
        raise FAIL("Fail Message")

This will have the task enter a failed state.

would it retry in case of fail?

I believe it would if the task's parameters allow it to.

right, thanks.. will try this

Theoretically you can do that, yeah. It think it is not recommended though and that just having your task return something is a more "prefectic way". Actually, you could also have your task fail by raising any error that you would not catch e.g.

@task
def my_task:
   if condition:
       raise AttributeError("something went wrong")

@Zohaa Qamar As @Sylvain Hazard mentioned, the best way to solve it, would be to raise a signal that would end the task run execution. Raising FAILED signal respects retries. If you don’t want retries to be triggered, use ENDRUN:

from prefect.engine.signals import ENDRUN
from prefect import task

@task
def my_task():
   if condition:
        raise ENDRUN("Exiting the task execution...")

ENDRUN would stop the whole flow execution or would just stop that task and move to next ones?

it would stop the task. If you want to stop the entire flow, the easiest way to do it would be adding a conditional logic:

from prefect import task, Flow, case

@task(log_stdout=True)
def end_flow():
    print("Ending the flow run due to the XXX")

with Flow("conditional-logic") as flow:
    cond = check_condition()

    with case(cond, True):
        val = t1()
        val2 = t2()
        t3(val, val2)

    with case(cond, False):
        end_flow()

thanks!