Fix validation of datasets without metadata

[magdalenafuentes]

Fixes #341

[codecov]

Codecov Report

Merging #342 (8de5515) into master (20094b1) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

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##           master     #342      +/-   ##
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- Coverage   98.58%   98.58%   -0.01%     
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  Files          28       28              
  Lines        2692     2691       -1     
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- Hits         2654     2653       -1     
  Misses         38       38              

[genisplaja]

Thanks for this PR!! I am actually checking it because this morning I tried to change line 144 from utils.py to if 'metadata' in dataset_index and dataset_index['metadata'] is not None: just as this PR, because I thought that it is a good idea to keep the same dict structure for all the indexes even if there is no general metadata file, but it failed. Now I'm rerunning it because I think that it should work!

[magdalenafuentes]

Great! Thanks :) let me know and if it does I'll merge

[genisplaja]

I don't know if you have tried it but in my case isn't working yet (I am not removing metadata key from index). I don't know if the problem is when dumping and loading from the JSON index file (converting from None to null and viceversa), but I have debugged the code and tried some alternatives, and when running the code in this PR without deleting the metadata key, the error is still there.

Maybe the best idea is to directly remove the metadata key from the datasets that do not have general metadata and we specify, in this same PR, in the CONTRIBUTING.md file that the datasets with no general metadata must not include the key in the index.

[magdalenafuentes]

Mmmmm... that's strange. It is working for me locally both with metadata=null and without.

Is it not working for the test_full_dataset either on orchset and mridangam_stroke?

[magdalenafuentes]

both orchset and mridangam_stroke pass the full test locally for me

[genisplaja]

Mmmmm... that's strange. It is working for me locally both with metadata=null and without.

Is it not working for the test_full_dataset either on orchset and mridangam_stroke?

I haven't tried in orchset, but I tried it for mridangam_stroke and it broke. Yeah that's weird! Because I set an assert to check that content of metadata key was None and it was!

[genisplaja]

Btw if I remove the metadata field from the indexes it works perfectly!

[rabitt]

Quick comment - From a code structure perspective, it's better if any null top-level fields are removed, with the exception of version.

[genisplaja]

Ok! Understood. So then I guess we can leave the patch as @magdalenafuentes proposed and that would solve the issue. It's working for me now!