feat: EventRenamer handle event=None

[bentinata]

Summary

Let EventRenamer defaults to None in case event key is missing.

Long one (more context)

I'm new to python development in general. I am adding structlog to my uvicorn app, so that the logs are parseable by the logs processor. My current orgs setup expect message key, hence I am using EventRenamer. But when my logger get passed None or [] (empty array), it will break the logger.

Other considerations and questions:

Maybe let None be passed as event?

In the _base.py _process_event, there's this if-clause.

if event is not None:
    event_dict["event"] = event

I wonder why do this?

Other approach

I've added new custom processors like this:

def ensure_event_key(_, __, event_dict: EventDict) -> EventDict:
    if 'event' not in event_dict:
        event_dict['event'] = ''
    return event_dict

Pull Request Check List

I haven't done anything more than just this small change. I would like to validate my understanding first.

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[hynek]

Hi Ben, sorry for not getting back to you earlier.

Summary

Let EventRenamer defaults to None in case event key is missing.

Long one (more context)

I'm new to python development in general. I am adding structlog to my uvicorn app, so that the logs are parseable by the logs processor. My current orgs setup expect message key, hence I am using EventRenamer. But when my logger get passed None or [] (empty array), it will break the logger.

What kind of configuration are you using exactly? IIUC, you're violating the typing contract of the log methods that all require event to be a string?

I'm somewhat sure that you're doing something you shouldn't based on some misunderstanding so it would be better to sort that out first.

Other considerations and questions:

Maybe let None be passed as event?

In the _base.py _process_event, there's this if-clause.

if event is not None:
    event_dict["event"] = event

I wonder why do this?

I think this is from the olden days with a more dynamic logger implementation where event was in fact optional. Although I'm looking at stdlib and it looks like the type hints there are still str | None. 🙈