Log messages dispatched using the swift-log backend are missing normal swift-log formatting.

[thisisaaronland]

Log messages dispatched using the swift-log backend are missing normal swift-log formatting.

[ffried]

@thisisaaronland First of all a big thanks to you for a very well written issue here! Including a reproduction project and a very detailed explanation. This helps a log to understand what you're trying to do and to help you out!

Now to the problem at hand:
This is actually working as designed. In swift-log, formatting is done by the log handler. What you see when using the StreamLogHandler.standardOutput is done here. As soon as you use a different log handler (like the one CocoaLumberjack provides), this code is no longer executed.

You will need to do this formatting yourself using a DDLogFormatter and assign it to the logFormatter property on the DDFileLogger (or any DDLogger for that matter).

If you want consistent formatting, I'd actually recommend not using the Logger.MultiplexLogHandler, but using only CocoaLumberjacks LogHandler instead. Then you can use e.g. DDOSLogger for writing to os_log or use your own DDLogger implementation for writing to stdout. Both of the loggers can use the same log formatter and thus have the same formatting.

Small note, though: If you're using DDOSLogger, make your log formatter configurable to not include the date, because that will always be added by os_log.

Let me know if that helped or if you have any further questions!