Add file opener brotli.open for Python

[youknowone]

The goal of this PR is adding brotli.open like gzip.open.

The patch is not completed yet - but the basic function compress/decompress is done as proof of concept. file_test.py is testing it.

Before revising more, I want to know if this project is interested in this patch or not.

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[youknowone]

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[AppVeyorBot]

❌ Build brotli 1.0.0#1481 failed (commit 154f35a988 by @youknowone)

[AppVeyorBot]

❌ Build brotli 1.0.0#1482 failed (commit 7debde6096 by @youknowone)

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❌ Build brotli 1.0.0#1483 failed (commit b3d2289b67 by @youknowone)

[eustas]

Looks interesting.
Unfortunately, can't find the mentioned "Andrew Kuchling's minigzip.py". Could you share a link to it?

[youknowone]

I copied it from CPython stdlib. So actually I didn't see that file. This is the CPython file: https://github.com/python/cpython/blob/master/Lib/gzip.py#L6

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[youknowone]

I splited CPython contributed part as a seperated commit but it causes CLA warning. what should i do in this case?

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❌ Build brotli 1.0.0#1501 failed (commit f6b351df41 by @youknowone)

[youknowone]

By needs, I released this one as a seperated project at this time

• https://github.com/youknowone/brotli-file
• https://pypi.org/project/brotli-file/

Because dependencies are using Python3 for now, it needs a few tasks to finish this PR.
Let me know which things are requried below. Then I can work more for the patch

• test for file interface which can be written from CPython test_gzip.py
• CPython3-only availability check for the file interface - if this is ok approach
• Python2 and other pythons comaptibility work which including CPython _compression port

[eustas]

br_mode?

[brechtm]

@youknowone This would come in very handy, so I wanted to kindly ask whether you're interested in bringing this PR to completion. Thanks!

[youknowone]

@brechtm Since nobody having project ownership is interested in, I feel like spending more effort for this patch is not reasonable enough.

You can install a separated project using pip https://pypi.org/project/brotli-file/

[brechtm]

Thanks, @youknowone. I tried brotli-file, but unfortunately decompression is quite a bit slower than command-line brotli. I was planning on using brotli for compressing my CSV files which I read into pandas, but it seems pandas.read_csv() supports zstd directly (through python-zstandard), which does not suffer from a performance hit like brotli-file. Since it has better support for Python at this point, I'll be using zstd instead.

[jyrkialakuijala]

@brechtm Since nobody having project ownership

There is an unreplied and unresolved review finding from eustas@ (with project ownership) here: https://github.com/google/brotli/pull/806/files/3462440035eb969771455d8812e5e7ed95e66a5f#r1058955829