Hi! Whenever I rerun a flow, it reuses values from the previous run for the parameters declared globally. How should I handle this?

#!/usr/bin/python3

from datetime import datetime

from prefect import task, Flow, Parameter, context, case

from prefect.utilities.debug import is_serializable

logger = context.get("logger")

timestamp = datetime.now().strftime("%Y-%m-%dT%H-%M-%S")

@task

def print_timestamp():

<http://logger.info|logger.info>(timestamp)

with Flow("Test") as flow:

    

print_timestamp()

serializable = is_serializable(flow)

if serializable:

    

flow.register(project_name="Default",

                  

idempotency_key=flow.serialized_hash())

flow.run()

Attached screenshot from two runs. As you could see, the value of the global parameter

timestamp

hasn't changed

Hi @fblaze f! Since you’re creating that timestamp at Flow build time (i.e. as part of the definition outside of a Task), that value won’t be re-created when the Flow is run. If instead you create the timestamp inside of a Task, it should behave as you expect

Thank you. That helps!

Great! :marvin: