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Hi everyone, i'm currently transforming some previous Prefect flow to the Prefect 2.0.....i encountered some issues during migration
• How can I write log into the local file? In 1.0, i use python's file handler and add that handler to the Prefect logger. However, in 2.0, it seems there's no addHandler method in Prefect logger.

See <https://docs.prefect.io/concepts/logs/?h=logging#logging-configuration>

Basically, we expose all of Python’s logging settings to you <https://github.com/PrefectHQ/prefect/blob/orion/src/prefect/logging/logging.yml>

HI Michael, I still not fully understand....so you mean I can just add a file handler into the logging.yml in handlers section?

Maybe this can help too <https://discourse.prefect.io/t/prefect-logging-faq/1476>

Thanks <@U0330PHG76J>, but i still have no idea how to add a local file handler directly in the python code......is there a handy way to add the File Handler to the Prefect 2.0 logger so the log can be written during flow run?

I saw there's way to add extra logger from yaml.....but is that going to be global instead of flow specific? as i only want to log one specific flow

my guess is using logging.yml and then <https://discourse.prefect.io/t/how-to-add-extra-loggers-to-prefect-2-0/1040>

but no way to attach handler directly to Prefect logger? :(

<https://discourse.prefect.io/t/how-do-i-suppress-created-task-run-logs/750/7?u=ahuang11>

great! if you figure it out, feel free to post on the discourse so it can be shared with others too (or reply back here and I can post it for you)

<@U0330PHG76J> I actually figured out a way to add FileHandler to specific flow. The part in Italic is the key. This solution is similar to the one I used in Prefect 1.0 but I have to add separately to both Flow and Task logger in Prefect 2.0.

import prefect
from prefect import flow, task

import logging
from datetime import datetime

@task
def string_prep(ct):
    return ct.strftime("%H:%M:%S")

@flow()
def dynamic_parameter(ct=datetime.now()):
    _#Add File Handler to both flow and task logger_
    _flow_logger = logging.getLogger('prefect.flow_runs')_
    _task_logger = logging.getLogger('prefect.task_runs')_

    _handler = logging.FileHandler(filename=&lt;replace with your own log file path&gt;)_
    _handler.setFormatter(logging.Formatter("%(asctime)s.%(msecs)03d | %(levelname)-7s | %(name)s - %(message)s"))_

    _flow_logger.addHandler(handler)_
    _task_logger.addHandler(handler)_

    #Actual Flow Part
    general_logger = prefect.logging.get_run_logger()

    strings = string_prep(ct)

    <http://general_logger.info|general_logger.info>('see see ' + strings)

awesome job! I’ll add to Discourse if you dont mind

<https://discourse.prefect.io/t/add-separate-logging-filehandlers-within-python-code-specific-to-a-flow/1498/> much appreciated

and also linked here for visibility <https://discourse.prefect.io/t/prefect-logging-faq/1476>