pybit7z

A Python wrapper around bit7z for creating and extracting 7-zip archives, with bundled external codec and format plugins.

Features

• Compression & extraction of 7z, zip, tar, gzip, bzip2, xz, wim archives (writing); reading support for 60+ formats (rar, iso, cab, chm, nsis, vmdk, vhdx, squashfs, and more).
• Bundled external plugins — zstd, brotli, lz4, lz5, lizard, flzma2, bsc, and zpaq codecs/formats are packaged with the wheel and loaded automatically.
• In-memory operations — compress/extract directly to/from bytes buffers and strings.
• Archive metadata — inspect items count, sizes, CRC, per-item properties, wildcard item matching (items_matching), common root folder (root_folder), and property availability (item_has_property).
• Nested archive reading — BitNestedArchiveReader opens an archive embedded inside another (e.g. tar inside tar.gz).
• Lazy library loading — Bit7zLibraryLoader for explicit load/try-load/unload control, plus a loader_context() manager that auto-unloads on exit.
• Encryption — password-protected archives with optional header encryption (7z).
• Solid archives, multi-volume splitting, compression levels & methods, custom dictionary/word sizes, multi-threading.
• Command-line interface — pybit7z CLI for compress / decompress / extract / list / test / info / update.
• Python 3.9+ on Windows, macOS, and Linux (including musllinux).

Installation

Install from PyPI:

pip install pybit7z

Quick Start

All operations require a Bit7zLibrary instance. Use the lib7zip_context() context manager, which locates the bundled lib7zip automatically:

import pybit7z

with pybit7z.lib7zip_context() as lib:
    ...

For more control over the library lifecycle — e.g. probing whether 7-zip is available without raising, loading a custom build, or deferring the load — use loader_context(). It yields a fresh Bit7zLibraryLoader; call load() or try_load() yourself, and the manager unloads automatically on exit:

import pybit7z

with pybit7z.loader_context() as loader:
    # Safe probe — never raises if the library is missing
    if loader.try_load(pybit7z.default_lib7zip()):
        lib = loader.library()
        ...
    else:
        print("lib7zip unavailable, skipping")
# loader.unload() called automatically on exit (if loaded)

Loading External Plugins

The bundled external codecs and format handlers (zstd, brotli, lz4, ...) are not loaded automatically by lib7zip_context(). Call load_plugins() with the plugin directory to register them. For each supplied path the library scans the Codecs/ subfolder first, then the Formats/ subfolder.

import pybit7z

with pybit7z.lib7zip_context() as lib:
    # Load the plugins bundled with the package
    lib.load_plugins([pybit7z.default_plugin_dir()])

    # Multiple directories can be supplied; results are accumulated
    # lib.load_plugins([pybit7z.default_plugin_dir(), "/path/to/more/plugins"])

Extract Files from an Archive

import pybit7z

try:
    with pybit7z.lib7zip_context() as lib:
        extractor = pybit7z.BitFileExtractor(lib, pybit7z.FormatSevenZip)
        extractor.extract("path/to/archive.7z", "out/dir/")

        # Extracting a specific file inside an archive
        extractor.extract_matching("path/to/archive.7z", "file.pdf", "out/dir/")

        # Extracting the first file of an archive to a buffer
        buffer: bytes = extractor.extract("path/to/archive.7z")

        # Extracting an encrypted archive
        extractor.set_password("password")
        extractor.extract("path/to/another/archive.7z", "out/dir/")
except pybit7z.BitException as e:
    ...  # handle the exception

Work on a single archive:

import pybit7z

try:
    with pybit7z.lib7zip_context() as lib:
        # Opening the archive
        archive = pybit7z.BitArchiveReader(lib, "path/to/archive.gz", pybit7z.FormatGZip)

        # Testing the archive
        archive.test()

        # Extracting the archive
        archive.extract_to("out/dir/")
except pybit7z.BitException as e:
    ...  # handle the exception

Compress Files into an Archive

import pybit7z

try:
    with pybit7z.lib7zip_context() as lib:
        compressor = pybit7z.BitFileCompressor(lib, pybit7z.FormatSevenZip)

        files = ["path/to/file1.jpg", "path/to/file2.pdf"]

        # Creating a simple zip archive
        compressor.compress(files, "output_archive.zip")

        # Creating a zip archive with a custom directory structure
        files_map: dict[str, str] = {
            "path/to/file1.jpg": "alias/path/file1.jpg",
            "path/to/file2.pdf": "alias/path/file2.pdf",
        }
        compressor.compress(files_map, "output_archive2.zip")

        # Compressing a directory
        compressor.compress_directory("dir/path/", "dir_archive.zip")

        # Creating an encrypted zip archive of two files
        compressor.set_password("password")
        compressor.compress_files(files, "protected_archive.zip")

        # Updating an existing zip archive
        compressor.set_update_mode(pybit7z.UpdateMode.Append)
        compressor.compress_files(files, "existing_archive.zip")

        # Compressing a single file into a buffer
        compressor2 = pybit7z.BitFileCompressor(lib, pybit7z.FormatBZip2)
        buffer: bytes = compressor2.compress_file(files[0])
except pybit7z.BitException as e:
    ...  # handle the exception

Work on a single archive:

import pybit7z

try:
    with pybit7z.lib7zip_context() as lib:
        archive = pybit7z.BitArchiveWriter(lib, pybit7z.FormatSevenZip)

        # Adding the items to be compressed (no compression is performed here)
        archive.add_file("path/to/file.txt")
        archive.add_directory("path/to/dir/")

        # Compressing the added items to the output archive
        archive.compress_to("output.7z")
except pybit7z.BitException as e:
    ...  # handle the exception

Read Archive Metadata

import pybit7z

try:
    with pybit7z.lib7zip_context() as lib:
        arc = pybit7z.BitArchiveReader(lib, "archive.7z", pybit7z.FormatSevenZip)

        # Printing archive metadata
        print(
            "Archive properties:",
            "\n  Items count: ", arc.items_count(),
            "\n  Folders count: ", arc.folders_count(),
            "\n  Files count: ", arc.files_count(),
            "\n  Size: ", arc.size(),
            "\n  Packed size: ", arc.pack_size(),
        )

        # Printing the metadata of the archived items
        print("Archived items")
        for item in arc:
            print(
                "    Item index: ", item.index(),
                "\n    Name: ", item.name(),
                "\n    Extension: ", item.extension(),
                "\n    Path: ", item.path(),
                "\n    IsDir: ", item.is_dir(),
                "\n    Size: ", item.size(),
                "\n    Packed size: ", item.pack_size(),
                "\n    CRC: ", item.crc(),
            )

        # Wildcard-match items by pattern
        txt_files = list(arc.items_matching("*.txt"))

        # Common root folder of all items (empty string if none)
        print("Root folder:", arc.root_folder())

        # Check whether an item exposes a given property
        if arc.item_has_property(0, pybit7z.BitProperty.Size):
            size = arc.item_at(0).item_property(pybit7z.BitProperty.Size)

        # Item native/raw name accessors
        item = arc.item_at(0)
        print("Native name:", item.native_name())
        print("Raw path:", item.raw_path())
except pybit7z.BitException as e:
    ...  # handle the exception

A complete API reference is available in the documentation.

Command-Line Interface

pybit7z ships a command-line tool for everyday archive tasks:

# Compress
pybit7z compress file.txt -o out.7z
pybit7z compress dir/ -o out.zip -f zip -l Ultra

# Extract
pybit7z extract archive.7z -o out_dir/
pybit7z decompress archive.tar.gz -o out_dir/

# List / test
pybit7z list archive.7z
pybit7z test archive.7z

# Show supported formats and codecs
pybit7z info

The bundled external codecs and formats are loaded automatically. To load additional plugins from custom directories, use the --plugin-dir option (can be repeated). Each directory is scanned for Codecs/ and Formats/ subfolders:

pybit7z compress file.txt -o out.zst --plugin-dir /path/to/plugins

Run pybit7z --help for the full option list (passwords, compression method, threads, volumes, filtering, stdin/stdout piping, and more).

Supported Formats & Codecs

pybit7z bundles the full 7-zip format/codec set plus additional external plugins. Run pybit7z info to see the exact list available in your build.

Writable formats

7z, zip, tar, gzip, bzip2, xz, wim

Readable formats (60+)

7z, zip, tar, gzip, bzip2, xz, z, lzma, lzma86, apfs, arj, cab, chm, cpio, cramfs, dmg, elf, ext, fat, flv, gpt, hfs, ihex, iso, lzh, macho, mbr, mslz, mub, ntfs, pe, coff, te, ppmd, qcow, rar, rar5, rpm, squashfs, swf, swfc, uefic, vdi, vhd, vhdx, vmdk, xar, udf, wim, nsis, split, and more.

Bundled external codecs & formats

Plugin	Type	Description
zstd	format + codec	Zstandard compression
brotli	format + codec	Brotli compression
lz4	format + codec	LZ4 compression
lz5	format + codec	LZ5 compression
lizard	format + codec	Lizard (LZ5) compression
flzma2	codec	Fast LZMA2
bsc	codec	BSC (libbsc) compression
zpaq	codec	ZPAQ compression

These are packaged inside the wheel under the package's Codecs/ and Formats/ subdirectories. Call lib.load_plugins([pybit7z.default_plugin_dir()]) to load them (the CLI does this automatically); no extra installation is required.

Building from Source

The build uses scikit-build-core + CMake + vcpkg (with custom overlay ports for bit7z and the external codec plugins).

Prerequisites

• Python 3.9+
• CMake ≥ 3.20
• Ninja
• A C++17 compiler (MSVC on Windows, GCC/Clang on Linux/macOS)
• uv (recommended) or pip

Build

# Editable install with verbose build output
uv pip install -e . -v

The build downloads and compiles 7-zip, bit7z, and the bundled codec plugins via vcpkg. This may take several minutes the first time.

Running tests

uv pip install -e ".[test]"
pytest

Development

The project uses pre-commit hooks for linting and formatting:

pre-commit install
pre-commit run -a

License

Apache Software License 2.0, for more details, see the LICENSE file.