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deflate API

This is a very thin Python wrapper Eric Biggers' excellent libdeflate.

Currently, it handles:

Compression and decompression of gzip data, with a very basic API

import deflate
level = 6  # The default; may be 1-12 for libdeflate.
compressed = deflate.gzip_compress(b"hello world!" * 1000, level)
original = deflate.gzip_decompress(compressed)

Compression and decompression of raw DEFLATE or zlib data

The original size of the decompressed data needs to be kept through additional logic.

import deflate
level = 6  # The default; may be 1-12 for libdeflate.
data = b"hello world!" * 1000
# DEFLATE
compressed = deflate.deflate_compress(data, level)
original = deflate.deflate_decompress(compressed, len(data))
# zlib
compressed = deflate.zlib_compress(data, level)
original = deflate.zlib_decompress(compressed, len(data))

CRC32 computation

import deflate
crc32 = deflate.crc32(b"hello world! ")  # initial
crc32 = deflate.crc32(b"hello universe!", crc32)  # continued

Adler-32 computation

import deflate
adler32 = deflate.adler32(b"hello world! ")  # initial
adler32 = deflate.adler32(b"hello universe!", adler32)  # continued

Installation

pip install deflate

By default, deflate will compile and statically link the bundled libdeflate when you build from source (or use the pre-compiled wheels). To link to a system-installed libdeflate, set the LIBDEFLATE_PREFIX environment variable and build from source:

LIBDEFLATE_PREFIX=/opt/homebrew/Cellar/libdeflate/1.20 pip install deflate --no-binary=deflate

Be warned: you can't use this wheel on a system without the referenced libdeflate.

Testing

pip install -r requirements-dev.lock
python -m pytest