.. attribute:: compression_level
A high-level means of setting other compression parameters that affect
- the speed and ratio of compressing data. Setting the level to zero uses
- :attr:`COMPRESSION_LEVEL_DEFAULT`.
+ the speed and ratio of compressing data.
+
+ Regular compression levels are greater than ``0``. Values greater than
+ ``20`` are considered "ultra" compression and require more memory than
+ other levels. Negative values can be used to trade off faster compression
+ for worse compression ratios.
+
+ Setting the level to zero uses :attr:`COMPRESSION_LEVEL_DEFAULT`.
.. attribute:: window_log
*format* is the archive format: one of
"zip" (if the :mod:`zlib` module is available), "tar", "gztar" (if the
:mod:`zlib` module is available), "bztar" (if the :mod:`bz2` module is
- available), or "xztar" (if the :mod:`lzma` module is available).
+ available), "xztar" (if the :mod:`lzma` module is available), or "zstdtar"
+ (if the :mod:`compression.zstd` module is available).
*root_dir* is a directory that will be the root directory of the
archive, all paths in the archive will be relative to it; for example,
- *gztar*: gzip'ed tar-file (if the :mod:`zlib` module is available).
- *bztar*: bzip2'ed tar-file (if the :mod:`bz2` module is available).
- *xztar*: xz'ed tar-file (if the :mod:`lzma` module is available).
+ - *zstdtar*: Zstandard compressed tar-file (if the :mod:`compression.zstd`
+ module is available).
You can register new formats or provide your own archiver for any existing
formats, by using :func:`register_archive_format`.
*extract_dir* is the name of the target directory where the archive is
unpacked. If not provided, the current working directory is used.
- *format* is the archive format: one of "zip", "tar", "gztar", "bztar", or
- "xztar". Or any other format registered with
+ *format* is the archive format: one of "zip", "tar", "gztar", "bztar",
+ "xztar", or "zstdtar". Or any other format registered with
:func:`register_unpack_format`. If not provided, :func:`unpack_archive`
will use the archive file name extension and see if an unpacker was
registered for that extension. In case none is found,
- *gztar*: gzip'ed tar-file (if the :mod:`zlib` module is available).
- *bztar*: bzip2'ed tar-file (if the :mod:`bz2` module is available).
- *xztar*: xz'ed tar-file (if the :mod:`lzma` module is available).
+ - *zstdtar*: Zstandard compressed tar-file (if the :mod:`compression.zstd`
+ module is available).
You can register new formats or provide your own unpacker for any existing
formats, by using :func:`register_unpack_format`.
Some facts and figures:
-* reads and writes :mod:`gzip`, :mod:`bz2` and :mod:`lzma` compressed archives
- if the respective modules are available.
+* reads and writes :mod:`gzip`, :mod:`bz2`, :mod:`compression.zstd`, and
+ :mod:`lzma` compressed archives if the respective modules are available.
* read/write support for the POSIX.1-1988 (ustar) format.
or paths outside of the destination. Previously, the filter strategy
was equivalent to :func:`fully_trusted <fully_trusted_filter>`.
+.. versionchanged:: 3.14
+
+ Added support for Zstandard compression using :mod:`compression.zstd`.
+
.. function:: open(name=None, mode='r', fileobj=None, bufsize=10240, **kwargs)
Return a :class:`TarFile` object for the pathname *name*. For detailed
+------------------+---------------------------------------------+
| ``'r:xz'`` | Open for reading with lzma compression. |
+------------------+---------------------------------------------+
+ | ``'r:zst'`` | Open for reading with Zstandard compression.|
+ +------------------+---------------------------------------------+
| ``'x'`` or | Create a tarfile exclusively without |
| ``'x:'`` | compression. |
| | Raise a :exc:`FileExistsError` exception |
| | Raise a :exc:`FileExistsError` exception |
| | if it already exists. |
+------------------+---------------------------------------------+
+ | ``'x:zst'`` | Create a tarfile with Zstandard compression.|
+ | | Raise a :exc:`FileExistsError` exception |
+ | | if it already exists. |
+ +------------------+---------------------------------------------+
| ``'a' or 'a:'`` | Open for appending with no compression. The |
| | file is created if it does not exist. |
+------------------+---------------------------------------------+
+------------------+---------------------------------------------+
| ``'w:xz'`` | Open for lzma compressed writing. |
+------------------+---------------------------------------------+
+ | ``'w:zst'`` | Open for Zstandard compressed writing. |
+ +------------------+---------------------------------------------+
Note that ``'a:gz'``, ``'a:bz2'`` or ``'a:xz'`` is not possible. If *mode*
is not suitable to open a certain (compressed) file for reading,
For modes ``'w:xz'``, ``'x:xz'`` and ``'w|xz'``, :func:`tarfile.open` accepts the
keyword argument *preset* to specify the compression level of the file.
+ For modes ``'w:zst'``, ``'x:zst'`` and ``'w|zst'``, :func:`tarfile.open`
+ accepts the keyword argument *level* to specify the compression level of
+ the file. The keyword argument *options* may also be passed, providing
+ advanced Zstandard compression parameters described by
+ :class:`~compression.zstd.CompressionParameter`. The keyword argument
+ *zstd_dict* can be passed to provide a :class:`~compression.zstd.ZstdDict`,
+ a Zstandard dictionary used to improve compression of smaller amounts of
+ data.
+
For special purposes, there is a second format for *mode*:
``'filemode|[compression]'``. :func:`tarfile.open` will return a :class:`TarFile`
object that processes its data as a stream of blocks. No random seeking will
| ``'r|xz'`` | Open an lzma compressed *stream* for |
| | reading. |
+-------------+--------------------------------------------+
+ | ``'r|zst'`` | Open a Zstandard compressed *stream* for |
+ | | reading. |
+ +-------------+--------------------------------------------+
| ``'w|'`` | Open an uncompressed *stream* for writing. |
+-------------+--------------------------------------------+
| ``'w|gz'`` | Open a gzip compressed *stream* for |
| ``'w|xz'`` | Open an lzma compressed *stream* for |
| | writing. |
+-------------+--------------------------------------------+
+ | ``'w|zst'`` | Open a Zstandard compressed *stream* for |
+ | | writing. |
+ +-------------+--------------------------------------------+
.. versionchanged:: 3.5
The ``'x'`` (exclusive creation) mode was added.
.. versionadded:: 3.3
+.. data:: ZIP_ZSTANDARD
+
+ The numeric constant for Zstandard compression. This requires the
+ :mod:`compression.zstd` module.
+
.. note::
- The ZIP file format specification has included support for bzip2 compression
- since 2001, and for LZMA compression since 2006. However, some tools
- (including older Python releases) do not support these compression
- methods, and may either refuse to process the ZIP file altogether,
- or fail to extract individual files.
+ In APPNOTE 6.3.7, the method ID ``20`` was assigned to Zstandard
+ compression. This was changed in APPNOTE 6.3.8 to method ID ``93`` to
+ avoid conflicts, with method ID ``20`` being deprecated. For
+ compatibility, the :mod:`!zipfile` module reads both method IDs but will
+ only write data with method ID ``93``.
+
+ .. versionadded:: 3.14
+
+.. note::
+ The ZIP file format specification has included support for bzip2 compression
+ since 2001, for LZMA compression since 2006, and Zstandard compression since
+ 2020. However, some tools (including older Python releases) do not support
+ these compression methods, and may either refuse to process the ZIP file
+ altogether, or fail to extract individual files.
.. seealso::
*compression* is the ZIP compression method to use when writing the archive,
and should be :const:`ZIP_STORED`, :const:`ZIP_DEFLATED`,
- :const:`ZIP_BZIP2` or :const:`ZIP_LZMA`; unrecognized
- values will cause :exc:`NotImplementedError` to be raised. If
- :const:`ZIP_DEFLATED`, :const:`ZIP_BZIP2` or :const:`ZIP_LZMA` is specified
- but the corresponding module (:mod:`zlib`, :mod:`bz2` or :mod:`lzma`) is not
+ :const:`ZIP_BZIP2`, :const:`ZIP_LZMA`, or :const:`ZIP_ZSTANDARD`;
+ unrecognized values will cause :exc:`NotImplementedError` to be raised. If
+ :const:`ZIP_DEFLATED`, :const:`ZIP_BZIP2`, :const:`ZIP_LZMA`, or
+ :const:`ZIP_ZSTANDARD` is specified but the corresponding module
+ (:mod:`zlib`, :mod:`bz2`, :mod:`lzma`, or :mod:`compression.zstd`) is not
available, :exc:`RuntimeError` is raised. The default is :const:`ZIP_STORED`.
If *allowZip64* is ``True`` (the default) zipfile will create ZIP files that
(see :class:`zlib <zlib.compressobj>` for more information).
When using :const:`ZIP_BZIP2` integers ``1`` through ``9`` are accepted
(see :class:`bz2 <bz2.BZ2File>` for more information).
+ When using :const:`ZIP_ZSTANDARD` integers ``-131072`` through ``22`` are
+ commonly accepted (see
+ :attr:`CompressionParameter.compression_level <compression.zstd.CompressionParameter.compression_level>`
+ for more on retrieving valid values and their meaning).
The *strict_timestamps* argument, when set to ``False``, allows to
zip files older than 1980-01-01 at the cost of setting the
read or append. *pwd* is the password used for encrypted files as a :class:`bytes`
object and, if specified, overrides the default password set with :meth:`setpassword`.
Calling :meth:`read` on a ZipFile that uses a compression method other than
- :const:`ZIP_STORED`, :const:`ZIP_DEFLATED`, :const:`ZIP_BZIP2` or
- :const:`ZIP_LZMA` will raise a :exc:`NotImplementedError`. An error will also
- be raised if the corresponding compression module is not available.
+ :const:`ZIP_STORED`, :const:`ZIP_DEFLATED`, :const:`ZIP_BZIP2`,
+ :const:`ZIP_LZMA`, or :const:`ZIP_ZSTANDARD` will raise a
+ :exc:`NotImplementedError`. An error will also be raised if the
+ corresponding compression module is not available.
.. versionchanged:: 3.6
Calling :meth:`read` on a closed ZipFile will raise a :exc:`ValueError`.
projects / thirdparty / Python / cpython.git / commitdiff
