pyzstd

• Support for Python 3.14
• Deprecate the read_size and write_size parameters of ZstdFile and SeekableZstdFile
• Deprecate richmem_compress and RichMemZstdCompressor
• Rework documentation to suggest using compression.zstd from Python stdlib, and provide a migration guide
• Include the zstd library license in package distributions

• Upgrade zstd source code from v1.5.6 to v1.5.7
• Raise an exception when attempting to decompress empty data
• Add ZstdFile.name property
• Deprecate (de)compress_stream functions
• Use a leading _ for private objects
• Build wheels for Windows ARM64
• Support for PyPy 3.11

• Build wheels for Python 3.13
• Deprecate support for Python version before 3.9 and stop building wheels for them

• Compatibility with Python 3.13

• Upgrade zstd source code from v1.5.5 to v1.5.6
• Fix pyzstd_pep517 parameter name in get_requires_for_build_wheel
• Deprecate support for Python version before 3.8 and stop building wheels for them
• Minor fixes in type hints
• Refactor README & CHANGELOG files

• Fix SeekableZstdFile class can't open new file in appending mode.
• Support sub-interpreter on CPython 3.12+, can utilize per-interpreter GIL.
• On CPython(3.5~3.12)+Linux, use another output buffer code that can utilize the mremap mechanism.
• Change repository URL and maintainer following the deletion of the GitHub account of the original author, Ma Lin (animalize). See #1.

ZstdFile class related changes:

• Add SeekableZstdFile class, it's a subclass of ZstdFile, supports Zstandard Seekable Format.
• Add mode argument to ZstdFile.flush() method, now it can flush a zstd frame.
• Add read_size and write_size arguments to ZstdFile.__init__() method, can work with Network File Systems better.
• Optimize ZstdFile performance to C language level.

ZstdDict class changes:

• Fix these advanced compression parameters may be ignored when loading a dictionary: windowLog, hashLog, chainLog, searchLog, minMatch, targetLength, strategy, enableLongDistanceMatching, ldmHashLog, ldmMinMatch, ldmBucketSizeLog, ldmHashRateLog, and some non-public parameters.
• When compressing, load undigested dictionary instead of digested dictionary by default. Loading again an undigested is slower, see differences.
• Add .as_prefix attribute. Can use zstd as a patching engine.

• Upgrade zstd source code from v1.5.4 to v1.5.5.

• Upgrade zstd source code from v1.5.2 to v1.5.4. v1.5.3 is a non-public release.
• Support pyproject.toml build mechanism (PEP-517). Note that specifying build options in old way may be invalid, see build commands.
• Support "multi-phase initialization" (PEP-489) on CPython 3.11+, can work with CPython sub-interpreters in the future. Currently this build option is disabled by default.
• Add a command line interface (CLI).

• Fix ZstdError object can't be pickled.

• Upgrade zstd source code from v1.5.1 to v1.5.2.

• Upgrade zstd source code from v1.5.0 to v1.5.1.
• Fix ZstdFile.write() / train_dict() / finalize_dict() may use wrong length for some buffer protocol objects.
• Two behavior changes:
  • Setting CParameter.nbWorkers to 1 now means "1-thread multi-threaded mode", rather than "single-threaded mode".
  • If the underlying zstd library doesn't support multi-threaded compression, no longer automatically fallback to "single-threaded mode", now raise a ZstdError exception.
• Add a module level variable zstd_support_multithread.
• Add a setup.py option --avx2, see build options.

• Upgrade zstd source code from v1.4.9 to v1.5.0.
• Some improvements, no API changes.

• Add a CFFI implementation that can work with PyPy.
• Allow dynamically link to zstd library.

• Upgrade zstd source code from v1.4.8 to v1.4.9.

• Add two convenient functions: compress_stream() and decompress_stream().
• Some improvements.

• Upgrade zstd source code from v1.4.5 to v1.4.8.
  • v1.4.6 is a non-public release for Linux kernel.
  • v1.4.8 is a hotfix for v1.4.7.
• Some improvements, no API changes.

• ZstdDecompressor class: now it has the same API and behavior as BZ2Decompressor / LZMADecompressor classes in Python standard library, it stops after a frame is decompressed.
• Add an EndlessZstdDecompressor class, it accepts multiple concatenated frames. It is renamed from previous ZstdDecompressor class, but .at_frame_edge is True when both the input and output streams are at a frame edge.
• Rename zstd_open() function to open(), consistent with Python standard library.
• decompress() function:
  • ~9% faster when: there is one frame, and the decompressed size was recorded in frame header.
  • raises ZstdError when input or output data is not at a frame edge. Previously, it only raise for output data is not at a frame edge.

• No longer use Argument Clinic, now supports Python 3.5+, previously 3.7+.