Fix #684 Abort S3 MultipartUpload if exception is raised

[lociko]

Motivation

• Fixes S3 Multipart uploads comitted on exception when using compression via context manager #684
  AWS Supports multipart upload of a file. I big file split by chunks uploaded one by one and on S3 concatenated again.
  In our case, if an exception is raised while processing one of the parts we have to abort uploading to avoid corrupted file creation.

Tests

test_write_gz_with_error

[ddelange]

Hi 👋 can this be generalized such that it doesn't just handle S3, but also the other adapters like Azure?

Azure exception handling ref #783

[ddelange]

e.g. by refactoring tweak_close to become tweak_exit, that patches .__exit__() instead of .close()?

[ddelange]

opened #786

[leeprevost]

What do I need to do to install this? I'm running into situation where larger transfers fail with this error:

botocore.exceptions.ClientError('An error occurred (EntityTooLarge) when calling the UploadPart operation: Your proposed upload exceeds the maximum allowed size')

[ddelange]

• this PR was superceded by Propagate __exit__ call to underlying filestream #786
• large S3 uploads was fixed in Add logic for handling large files in MultipartWriter uploads to s3 #796
• both are unreleased so for now you can pip install 'smart_open[s3] @ https://github.com/piskvorky/smart_open/archive/02b8be2577821c1a6d30e6321c07aa6dbc690a2f.zip'

[mpenkov]

Closing, thank you