Feature #13020: Zlib.gzip and Zlib.gunzip

• Status: Closed
• Assignee: -
• Target version: -

[naruse (Yui NARUSE)]

I added Zlib.deflate/inflate [Feature #4180] before, but writing/reading gzip is still too complex.
It should have shorthand method.

[naruse (Yui NARUSE)]

• Status changed from Open to Closed

Applied in changeset r57035.

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Zlib.gzip and Zlib.gunzip [Feature #13020]

Encode and Decode gzip data without creating files.

[normalperson (Eric Wong)]

[e-mail] wrote:

I added Zlib.deflate/inflate [Feature #4180] before, but writing/reading gzip is still too complex.
It should have shorthand method.

I like the convenience, but I think encouraging use of
potentially large String buffers is dangerous.

It causes memory problems and even opens up DoS attacks.

So, I think it would be better if it used IO-like object
instead, to discourage slurping.

Maybe make it like IO.copy_stream:

Zlib.gzip(src_io, dst_io)
Zlib.gunzip(src_io, dst_io)

Slurpers can still use StringIO if they want to.

In general, I am against non-streaming APIs and want to
encourage processing data in predictable sizes to avoid
fragmentation and OOM.

[znz (Kazuhiro NISHIYAMA)]

• Related to Bug #13021: `Zlib.gunzip` modifies argument String added

[naruse (Yui NARUSE)]

Eric Wong wrote:

[e-mail] wrote:

I added Zlib.deflate/inflate [Feature #4180] before, but writing/reading gzip is still too complex.
It should have shorthand method.

I like the convenience, but I think encouraging use of
potentially large String buffers is dangerous.

It causes memory problems and even opens up DoS attacks.

So, I think it would be better if it used IO-like object
instead, to discourage slurping.

Maybe make it like IO.copy_stream:

Zlib.gzip(src_io, dst_io)
Zlib.gunzip(src_io, dst_io)

Slurpers can still use StringIO if they want to.

In general, I am against non-streaming APIs and want to
encourage processing data in predictable sizes to avoid
fragmentation and OOM.

There's already Zlib.deflate/inflate, which are memory based API.
And gzip also uses deflate/inflate.
Note that gzip has the length of original data at the end of data. (isize=origsize / (2^32))

Anyway IO.copy_stream like API sounds reasonable.
Current API needs to change interface to use keyword arguments to avoid using 2nd argument...