related: #49966

Why

When setting AIRFLOW__LOGGING__CELERY_STDOUT_STDERR_SEPARATION=True, it will use DEFAULT_TASK_LOG_FMT as the log format.

However, DEFAULT_TASK_LOG_FMT contains task_name and task_id which are not handled by the default logging.Formatter.

>>> from celery.app.defaults import DEFAULT_TASK_LOG_FMT
>>> print(DEFAULT_TASK_LOG_FMT)
[%(asctime)s: %(levelname)s/%(processName)s] %(task_name)s[%(task_id)s]: %(message)s

How

Use TaskFormatter from Celery to handle task_name and task_id.

Ref: https://github.com/celery/celery/blob/main/celery/app/log.py#L41-L42

What

Set AIRFLOW__LOGGING__CELERY_STDOUT_STDERR_SEPARATION=True.
Then start Airflow with: breeze start-airflow --executor CeleryExecutor --integration celery.

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