python-libzim

libzim module allows you to read and write ZIM files in Python. It provides a shallow python interface on top of the C++ libzim library.

It is primarily used in openZIM scrapers like sotoki or youtube2zim.

Installation

pip install libzim

Our PyPI wheels bundle a recent release of the C++ libzim and are available for the following platforms:

• macOS for x86_64 and arm64
• GNU/Linux for x86_64, armhf and aarch64
• Linux+musl for x86_64 and aarch64
• Windows for x64
• Android for arm64_v8a and x86_64 with CPython 3.13+

Wheels are available for CPython only (but can be built for Pypy).

Free-threaded CPython is supported: the extension declares itself free-threading compatible, so importing it no longer forces the GIL back on. Only few methods support the GIL to be disabled; you must still prevent concurrent access to shared objects yourself (see Thread safety).

Users on other platforms can install the source distribution (see Building below).

Writer support is decided when the extension is built, not when it is installed: there is no install-time extra for it. Set LIBZIM_WITHOUT_WRITER=1 when building against a libzim compiled without writer support; such a build exposes the reader, search, suggestion, illustration and version modules only. Import libzim.writer in a try/except ImportError block to detect writer support at runtime. Android wheels are built without writer support, since libzim is compiled without it for Android.

Contributions

git clone git@github.com:openzim/python-libzim.git && cd python-libzim
# hatch run test:coverage

See CONTRIBUTING.md for additional details then Open a ticket or submit a Pull Request on Github 🤗!

Usage

Read a ZIM file

from libzim.reader import Archive
from libzim.search import Query, Searcher
from libzim.suggestion import SuggestionSearcher

zim = Archive("test.zim")
print(f"Main entry is at {zim.main_entry.get_item().path}")
entry = zim.get_entry_by_path("home/fr")
print(f"Entry {entry.title} at {entry.path} is {entry.get_item().size}b.")
print(bytes(entry.get_item().content).decode("UTF-8"))

# iterating over all entries (in the most efficient order to read them)
for entry in zim:
    print(entry.path, entry.title)

# searching using full-text index
search_string = "Welcome"
query = Query().set_query(search_string)
searcher = Searcher(zim)  # or Searcher() followed by searcher.add_archive(...)
search = searcher.search(query)
search_count = search.get_estimated_matches()
print(f"there are {search_count} matches for {search_string}")
for result in search.get_results(0, search_count):
    print(result.archive, result.path, result.title, result.snippet)

# accessing suggestions
search_string = "kiwix"
suggestion_searcher = SuggestionSearcher(zim)
suggestion = suggestion_searcher.suggest(search_string)
suggestion_count = suggestion.get_estimated_matches()
print(f"there are {suggestion_count} matches for {search_string}")
print(list(suggestion.get_results(0, suggestion_count)))

Write a ZIM file

import base64
import pathlib

from libzim.writer import Creator, Item, StringProvider, FileProvider, Hint


class MyItem(Item):
    def __init__(self, title, path, content="", fpath=None):
        super().__init__()
        self.path = path
        self.title = title
        self.content = content
        self.fpath = fpath

    def get_path(self):
        return self.path

    def get_title(self):
        return self.title

    def get_mimetype(self):
        return "text/html"

    def get_contentprovider(self):
        if self.fpath is not None:
            return FileProvider(self.fpath)
        return StringProvider(self.content)

    def get_hints(self):
        return {Hint.FRONT_ARTICLE: True}


content = """<html><head><meta charset="UTF-8"><title>Web Page Title</title></head>
<body><h1>Welcome to this ZIM</h1><p>Kiwix</p></body></html>"""

pathlib.Path("home-fr.html").write_text(
    """<html><head><meta charset="UTF-8">
    <title>Bonjour</title></head>
    <body><h1>this is home-fr</h1></body></html>"""
)

item = MyItem("Hello Kiwix", "home", content)
item2 = MyItem("Bonjour Kiwix", "home/fr", None, "home-fr.html")

# illustration = pathlib.Path("icon48x48.png").read_bytes()
illustration = base64.b64decode(
    "iVBORw0KGgoAAAANSUhEUgAAADAAAAAwAQMAAABtzGvEAAAAGXRFWHRTb2Z0d2FyZQBB"
    "ZG9iZSBJbWFnZVJlYWR5ccllPAAAAANQTFRFR3BMgvrS0gAAAAF0Uk5TAEDm2GYAAAAN"
    "SURBVBjTY2AYBdQEAAFQAAGn4toWAAAAAElFTkSuQmCC"
)

with Creator("test.zim").config_indexing(True, "eng") as creator:
    creator.set_mainpath("home")
    creator.add_item(item)
    creator.add_item(item2)
    # square illustration at scale 1
    creator.add_illustration(illustration, 48)
    for name, value in {
        "creator": "python-libzim",
        "description": "Created in python",
        "name": "my-zim",
        "publisher": "You",
        "title": "Test ZIM",
        "language": "eng",
        "date": "2024-06-30",
    }.items():

        creator.add_metadata(name.title(), value)

Thread safety

The reading part of the libzim is most of the time thread safe. Searching and creating part are not. libzim documentation

python-libzim disables the GIL on most of C++ libzim calls. You must prevent concurrent access yourself. This is easily done by wrapping all creator calls with a threading.Lock()

lock = threading.Lock()
with Creator("test.zim") as creator:

    # Thread #1
    with lock:
        creator.add_item(item1)

    # Thread #2
    with lock:
        creator.add_item(item2)

Type hints

libzim being a binary extension, there is no Python source to provide types information. We provide them as type stub files. When using pyright, you would normally receive a warning when importing from libzim as there could be discrepencies between actual sources and the (manually crafted) stub files.

You can disable the warning via reportMissingModuleSource = "none".

Building

libzim package building offers different behaviors via environment variables

Building on Windows

On Windows, built wheels needs to be fixed post-build to move the bundled DLLs (libzim and libicu) next to the wrapper (Windows does not support runtime path).

After building you wheel, run

python setup.py repair_win_wheel --wheel=dist/xxx.whl --destdir wheels\

Similarily, if you install as editable (pip install -e .), you need to place those DLLs at the root of the repo.

Move-Item -Force -Path .\libzim\*.dll -Destination .\

Examples

Default: downloading and bundling most appropriate libzim release binary

python3 -m build

Using system libzim (brew, debian or manually installed) - not bundled

# using system-installed C++ libzim
brew install libzim  # macOS
apt-get install libzim-devel  # debian
dnf install libzim-dev  # fedora
USE_SYSTEM_LIBZIM=1 python3 -m build --wheel

# using a specific C++ libzim
USE_SYSTEM_LIBZIM=1 \
CFLAGS="-I/usr/local/include" \
LDFLAGS="-L/usr/local/lib"
DYLD_LIBRARY_PATH="/usr/local/lib" \
LD_LIBRARY_PATH="/usr/local/lib" \
python3 -m build --wheel

Other platforms

On platforms for which there is no official binary available, you'd have to compile C++ libzim from source first then either use DONT_DOWNLOAD_LIBZIM or USE_SYSTEM_LIBZIM.

License

GPLv3 or later, see LICENSE for more details.