Comment by 10987654321

Not sure about lnav but most log aggregation systems support json and logfmt-formatted logs, and there are many standard logging libraries that supports emitting those formats

Of those json is better if you want to be able to do more advanced stuff (nest dictionaries, use lists, ...) and logfmt is better if you want to have human-readable logs without external tools as well, an example line can look like

    msg="Request finished" tag=request_finish status=200 [email protected] user_id=1234 app=mutelight app_id=1234

Some more info here https://www.brandur.org/logfmt