upmerge #170 - logging interface extension for debug logging

[gbirchmeier]

Merged @ligu's #170 submission to master

[gbirchmeier]

Hey, @ligu - your fix is really really good. I did make some slight changes and add some documentation. I still need to do some manual testing. (I also renamed "Debug" config to "ExtraDebugLogging".)

I'd appreciate it if you'd have a look at my additions and welcome any comments you might have.

[roji]

Sorry to jump in, but out of curiosity, is there a reasons for not using one of the standard logging libraries (e.g. NLog, log4net), or better yet, Commons.Logging as an abstraction layer to allow plugging into whatever library the embedding application happens to use?

In my case we use NLog, and I've had to implement a bridge from QuickFixN ILog to NLog, it was trivial but seems unnecessary?

[gbirchmeier]

@roji - We don't use another log library simply because no one has implemented it. I'm not opposed to it.

[roji]

@gbirchmeier and @ligu, I can devote a little bit of time next week to integrating Common.Logging (https://github.com/net-commons/common-logging) for the event/debug logs (not sure if the incoming/outgoing logging should be changed as well, what do you think?).

This would probably roll back/modify some of the work in this pull request. Specifically, ILog would no longer have OnEvent() and OnDebug() methods at all, since these would go to Common.Logging instead.

Do you guys think this is a good idea?

[gbirchmeier]

@roji - I think you are proposing a good thing. Can you open a new issue for us to discuss it?

[gbirchmeier]

Actually, @roji, wouldn't it just make sense to create a CommonLoggerLogFactory? Then people can choose to use Common.Logging or stay with the existing loggers. You wouldn't need to rewrite anything.

[ligu]

Altough I've put a lot of effort to extend logging functionality based on the "traditional" logging infrastructure, I agree with @roji that it would worth the work to overthrow the old logging with a well designed Common.Logging solution.

And if decision has been made, I suggest the complete change: logging of messages, events, debug, everything to the new logging framework, total removal of old logging from everywhere, no "half work"!
Sure, this would be a new major version...

I absolutele encourage to continue the work started in #205 !

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
1 out of 2 committers have signed the CLA.

✅ gbirchmeier
❌ ligu
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[gbirchmeier]

Closing for staleness. Keep an eye on the QF/n mailing list though, I do want to open discussion about logging revisions.