To change the default log settings, use the following environment variable format:
prefect config set PREFECT_LOGGING_LEVEL=DEBUG
export PREFECT_LOGGING_DEFAULT_FORMAT="%(levelname)s - %(name)s | %(message)s"
You can specify custom formatting by:
- setting an environment variable (as shown above)
- modifying the formatter in a
logging.ymlfile - here is the default config file.
You can also set a custom format for flow run or task run logs. The variables available to interpolate in log messages vary by the type of logger. Here is an example setting a custom format for flow run logs:
export PREFECT_LOGGING_FORMATTERS_FLOW_RUNS_FORMAT="%(asctime)s.%(msecs)03d | %(levelname)-7s | %(flow_run_id)s - %(message)s"
The resulting messages, using the flow run ID instead of name, would look like this:
10:40:01.211 | INFO | e43a5a80-417a-41c4-a39e-2ef7421ee1fc - Created task run
'othertask-1c085beb-3' for task 'othertask'
For more information related to logging settings, see:
- the logging configuration docs
- the API reference of the LoggingSettings
Prefect 1.0
Prefect 1.0 works works similarly but it uses a slightly different syntax:
export PREFECT__LOGGING__LEVEL=DEBUG
export PREFECT__LOGGING__FORMAT="%(levelname)s - %(name)s | %(message)s"