[Bug Fix] Allow logger to support indexing

[zippeurfou]

What does this PR do?

This should fix #4540

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[pep8speaks]

Hello @zippeurfou! Thanks for updating this PR.

There are currently no PEP 8 issues detected in this Pull Request. Cheers! 🍻

Comment last updated at 2020-12-05 20:10:44 UTC

[codecov]

Codecov Report

Merging #4595 (b61a77c) into master (16fa4ed) will increase coverage by 3%.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master   #4595    +/-   ##
=======================================
+ Coverage      90%     93%    +3%     
=======================================
  Files         129     129            
  Lines        9359    9363     +4     
=======================================
+ Hits         8411    8681   +270     
+ Misses        948     682   -266     

[SkafteNicki]

Hi @zippeurfou
Please include a test that would currently fail on master but pass with this PR :]

[zippeurfou]

Sure happy to do so.

[Borda]

@SkafteNicki mind bring a bit light on how this fixes the LF issue?
eventually, this yields an infinite loop if you have miss LoggerCollection and base logger

[SkafteNicki]

@Borda the problem currently is that neither DummyExperiment and DummyLogger supports indexing, so if the users has something like this in their code:
self.logger[0].experiment.add_image(...)
or
self.logger.experiment[0].add_image(...)
currently lr finder will crash as it temporarily replaces the user logger with a DummyLogger.

Can you elaborate in which case this can give an infinite loop?

[tchaton]

Looks slightly weird to me. Do you have any other solution in mind ?

[Borda]

lgtm