@Marvin how do i instruct a custom logger to flush its logs programmatically?

To programmatically instruct a custom logger to flush its logs, you typically need to call a method on the logger object that triggers the flush operation. Unfortunately, the Prefect documentation excerpts I retrieved do not directly address custom logger flushing. Generally speaking, in Python's standard logging, you would call the

flush

method on the log handler you want to flush. Here is an example of how you might do it, assuming you have a setup for a custom logger:

python
import logging

# Create your custom logger
logger = logging.getLogger('my_custom_logger')

# Add the log handler that you want to control
log_handler = logging.StreamHandler()
logger.addHandler(log_handler)

# Do your logging
<http://logger.info|logger.info>('Some log message')

# Flush the logs explicitly
log_handler.flush()

Please note, Prefect's logging behavior can be customized through their settings, and their logging system manages flows and tasks logs efficiently. However, if you have implemented your own custom logging handler within a Prefect flow, you would flush logs as you would in any regular Python application. If this doesn't help, or you want documentation specifically tied to Prefect logger flushing, consider consulting the Prefect Discourse community or checking the Prefect GitHub issues for more information.

My custom logger handler is defined within my

prefect.yml

file. How do i access this handler in my flow so i can tell it to flush?

In Prefect 2.0 and later, logging configuration can be customized via a

logging.yml

file. To access and control a custom logger handler that's defined in

prefect.yml

, you would typically set the logger up in the

logging.yml

and then retrieve a logger instance within your flow using Prefect's

get_run_logger()

function. You can customize your logger in a

logging.yml

file, which you then point to using the

PREFECT_LOGGING_SETTINGS_PATH

environment variable or place at the default location

/.prefect/logging.yml

. However, specific instructions on how to flush the logs of a logger configured via

prefect.yml

weren't detailed in the documentation excerpts provided. Assuming the handlers in your

logging.yml

are standard Python logging handlers, you could retrieve your logger using

get_run_logger()

in your task or flow:

python
from prefect import get_run_logger

logger = get_run_logger()

# ... Your task or flow logic ...

# To flush the logs of your logger, you would access the handlers attached to the logger.
# Assuming you have a single handler you can do the following:
if logger.handlers:
    for handler in logger.handlers:
        handler.flush()

Keep in mind that the

get_run_logger()

function is the one to be used to retrieve a logger instance within tasks in Prefect 2.0, and the same logger instance will be obtained every time you call this function within the same task or flow run. For detailed instructions on customizing the logging behavior and the configuration file, you might want to refer directly to the Prefect logging guide here: Prefect 2.0 Logging Guide. If you don't find what you need in there, consider reaching out to Prefect's community resources for more specific guidance.