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:mod:`!zipfile` --- Work with ZIP archives

.. module:: zipfile
   :synopsis: Read and write ZIP-format archive files.

.. moduleauthor:: James C. Ahlstrom <[email protected]>
.. sectionauthor:: James C. Ahlstrom <[email protected]>

Source code: :source:`Lib/zipfile/`


The ZIP file format is a common archive and compression standard. This module provides tools to create, read, write, append, and list a ZIP file. Any advanced use of this module will require an understanding of the format, as defined in PKZIP Application Note.

This module does not currently handle multi-disk ZIP files. It can handle ZIP files that use the ZIP64 extensions (that is ZIP files that are more than 4 GiB in size). It supports decryption of encrypted files in ZIP archives, but it currently cannot create an encrypted file. Decryption is extremely slow as it is implemented in native Python rather than C.

The module defines the following items:

.. exception:: BadZipFile

   The error raised for bad ZIP files.

   .. versionadded:: 3.2


.. exception:: BadZipfile

   Alias of :exc:`BadZipFile`, for compatibility with older Python versions.

   .. deprecated:: 3.2


.. exception:: LargeZipFile

   The error raised when a ZIP file would require ZIP64 functionality but that has
   not been enabled.


The class for reading and writing ZIP files. See section :ref:`zipfile-objects` for constructor details.

Class that implements a subset of the interface provided by :class:`pathlib.Path`, including the full :class:`importlib.resources.abc.Traversable` interface.

.. versionadded:: 3.8

Class for creating ZIP archives containing Python libraries.

Class used to represent information about a member of an archive. Instances of this class are returned by the :meth:`.getinfo` and :meth:`.infolist` methods of :class:`ZipFile` objects. Most users of the :mod:`zipfile` module will not need to create these, but only use those created by this module. filename should be the full name of the archive member, and date_time should be a tuple containing six fields which describe the time of the last modification to the file; the fields are described in section :ref:`zipinfo-objects`.

.. versionchanged:: 3.13
   A public :attr:`!compress_level` attribute has been added to expose the
   formerly protected :attr:`!_compresslevel`.  The older protected name
   continues to work as a property for backwards compatibility.


.. method:: _for_archive(archive)

   Resolve the date_time, compression attributes, and external attributes
   to suitable defaults as used by :meth:`ZipFile.writestr`.

   Returns self for chaining.

   .. versionadded:: 3.14
.. function:: is_zipfile(filename)

   Returns ``True`` if *filename* is a valid ZIP file based on its magic number,
   otherwise returns ``False``.  *filename* may be a file or file-like object too.

   .. versionchanged:: 3.1
      Support for file and file-like objects.


.. data:: ZIP_STORED

   The numeric constant for an uncompressed archive member.


.. data:: ZIP_DEFLATED

   The numeric constant for the usual ZIP compression method.  This requires the
   :mod:`zlib` module.


.. data:: ZIP_BZIP2

   The numeric constant for the BZIP2 compression method.  This requires the
   :mod:`bz2` module.

   .. versionadded:: 3.3

.. data:: ZIP_LZMA

   The numeric constant for the LZMA compression method.  This requires the
   :mod:`lzma` module.

   .. versionadded:: 3.3

   .. 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.


.. seealso::

   `PKZIP Application Note`_
      Documentation on the ZIP file format by Phil Katz, the creator of the format and
      algorithms used.

   `Info-ZIP Home Page <https://infozip.sourceforge.net/>`_
      Information about the Info-ZIP project's ZIP archive programs and development
      libraries.


ZipFile Objects

.. method:: ZipFile.close()

   Close the archive file.  You must call :meth:`close` before exiting your program
   or essential records will not be written.


.. method:: ZipFile.getinfo(name)

   Return a :class:`ZipInfo` object with information about the archive member
   *name*.  Calling :meth:`getinfo` for a name not currently contained in the
   archive will raise a :exc:`KeyError`.


.. method:: ZipFile.infolist()

   Return a list containing a :class:`ZipInfo` object for each member of the
   archive.  The objects are in the same order as their entries in the actual ZIP
   file on disk if an existing archive was opened.


.. method:: ZipFile.namelist()

   Return a list of archive members by name.


.. method:: ZipFile.open(name, mode='r', pwd=None, *, force_zip64=False)

   Access a member of the archive as a binary file-like object.  *name*
   can be either the name of a file within the archive or a :class:`ZipInfo`
   object.  The *mode* parameter, if included, must be ``'r'`` (the default)
   or ``'w'``.  *pwd* is the password used to decrypt encrypted ZIP files as a
   :class:`bytes` object.

   :meth:`~ZipFile.open` is also a context manager and therefore supports the
   :keyword:`with` statement::

      with ZipFile('spam.zip') as myzip:
          with myzip.open('eggs.txt') as myfile:
              print(myfile.read())

   With *mode* ``'r'`` the file-like object
   (``ZipExtFile``) is read-only and provides the following methods:
   :meth:`~io.BufferedIOBase.read`, :meth:`~io.IOBase.readline`,
   :meth:`~io.IOBase.readlines`, :meth:`~io.IOBase.seek`,
   :meth:`~io.IOBase.tell`, :meth:`~container.__iter__`, :meth:`~iterator.__next__`.
   These objects can operate independently of the ZipFile.

   With ``mode='w'``, a writable file handle is returned, which supports the
   :meth:`~io.BufferedIOBase.write` method.  While a writable file handle is open,
   attempting to read or write other files in the ZIP file will raise a
   :exc:`ValueError`.

   In both cases the file-like object has also attributes :attr:`!name`,
   which is equivalent to the name of a file within the archive, and
   :attr:`!mode`, which is ``'rb'`` or ``'wb'`` depending on the input mode.

   When writing a file, if the file size is not known in advance but may exceed
   2 GiB, pass ``force_zip64=True`` to ensure that the header format is
   capable of supporting large files.  If the file size is known in advance,
   construct a :class:`ZipInfo` object with :attr:`~ZipInfo.file_size` set, and
   use that as the *name* parameter.

   .. note::

      The :meth:`.open`, :meth:`read` and :meth:`extract` methods can take a filename
      or a :class:`ZipInfo` object.  You will appreciate this when trying to read a
      ZIP file that contains members with duplicate names.

   .. versionchanged:: 3.6
      Removed support of ``mode='U'``.  Use :class:`io.TextIOWrapper` for reading
      compressed text files in :term:`universal newlines` mode.

   .. versionchanged:: 3.6
      :meth:`ZipFile.open` can now be used to write files into the archive with the
      ``mode='w'`` option.

   .. versionchanged:: 3.6
      Calling :meth:`.open` on a closed ZipFile will raise a :exc:`ValueError`.
      Previously, a :exc:`RuntimeError` was raised.

   .. versionchanged:: 3.13
      Added attributes :attr:`!name` and :attr:`!mode` for the writeable
      file-like object.
      The value of the :attr:`!mode` attribute for the readable file-like
      object was changed from ``'r'`` to ``'rb'``.


.. method:: ZipFile.extract(member, path=None, pwd=None)

   Extract a member from the archive to the current working directory; *member*
   must be its full name or a :class:`ZipInfo` object.  Its file information is
   extracted as accurately as possible.  *path* specifies a different directory
   to extract to.  *member* can be a filename or a :class:`ZipInfo` object.
   *pwd* is the password used for encrypted files as a :class:`bytes` object.

   Returns the normalized path created (a directory or new file).

   .. note::

      If a member filename is an absolute path, a drive/UNC sharepoint and
      leading (back)slashes will be stripped, e.g.: ``///foo/bar`` becomes
      ``foo/bar`` on Unix, and ``C:\foo\bar`` becomes ``foo\bar`` on Windows.
      And all ``".."`` components in a member filename will be removed, e.g.:
      ``../../foo../../ba..r`` becomes ``foo../ba..r``.  On Windows illegal
      characters (``:``, ``<``, ``>``, ``|``, ``"``, ``?``, and ``*``)
      replaced by underscore (``_``).

   .. versionchanged:: 3.6
      Calling :meth:`extract` on a closed ZipFile will raise a
      :exc:`ValueError`.  Previously, a :exc:`RuntimeError` was raised.

   .. versionchanged:: 3.6.2
      The *path* parameter accepts a :term:`path-like object`.


.. method:: ZipFile.extractall(path=None, members=None, pwd=None)

   Extract all members from the archive to the current working directory.  *path*
   specifies a different directory to extract to.  *members* is optional and must
   be a subset of the list returned by :meth:`namelist`.  *pwd* is the password
   used for encrypted files as a :class:`bytes` object.

   .. warning::

      Never extract archives from untrusted sources without prior inspection.
      It is possible that files are created outside of *path*, e.g. members
      that have absolute filenames starting with ``"/"`` or filenames with two
      dots ``".."``.  This module attempts to prevent that.
      See :meth:`extract` note.

   .. versionchanged:: 3.6
      Calling :meth:`extractall` on a closed ZipFile will raise a
      :exc:`ValueError`.  Previously, a :exc:`RuntimeError` was raised.

   .. versionchanged:: 3.6.2
      The *path* parameter accepts a :term:`path-like object`.


.. method:: ZipFile.printdir()

   Print a table of contents for the archive to ``sys.stdout``.


.. method:: ZipFile.setpassword(pwd)

   Set *pwd* (a :class:`bytes` object) as default password to extract encrypted files.


.. method:: ZipFile.read(name, pwd=None)

   Return the bytes of the file *name* in the archive.  *name* is the name of the
   file in the archive, or a :class:`ZipInfo` object.  The archive must be open for
   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.

   .. versionchanged:: 3.6
      Calling :meth:`read` on a closed ZipFile will raise a :exc:`ValueError`.
      Previously, a :exc:`RuntimeError` was raised.


.. method:: ZipFile.testzip()

   Read all the files in the archive and check their CRC's and file headers.
   Return the name of the first bad file, or else return ``None``.

   .. versionchanged:: 3.6
      Calling :meth:`testzip` on a closed ZipFile will raise a
      :exc:`ValueError`.  Previously, a :exc:`RuntimeError` was raised.


.. method:: ZipFile.write(filename, arcname=None, compress_type=None, \
                          compresslevel=None)

   Write the file named *filename* to the archive, giving it the archive name
   *arcname* (by default, this will be the same as *filename*, but without a drive
   letter and with leading path separators removed).  If given, *compress_type*
   overrides the value given for the *compression* parameter to the constructor for
   the new entry. Similarly, *compresslevel* will override the constructor if
   given.
   The archive must be open with mode ``'w'``, ``'x'`` or ``'a'``.

   .. note::

      The ZIP file standard historically did not specify a metadata encoding,
      but strongly recommended CP437 (the original IBM PC encoding) for
      interoperability.  Recent versions allow use of UTF-8 (only).  In this
      module, UTF-8 will automatically be used to write the member names if
      they contain any non-ASCII characters.  It is not possible to write
      member names in any encoding other than ASCII or UTF-8.

   .. note::

      Archive names should be relative to the archive root, that is, they should not
      start with a path separator.

   .. note::

      If ``arcname`` (or ``filename``, if ``arcname`` is  not given) contains a null
      byte, the name of the file in the archive will be truncated at the null byte.

   .. note::

      A leading slash in the filename may lead to the archive being impossible to
      open in some zip programs on Windows systems.

   .. versionchanged:: 3.6
      Calling :meth:`write` on a ZipFile created with mode ``'r'`` or
      a closed ZipFile will raise a :exc:`ValueError`.  Previously,
      a :exc:`RuntimeError` was raised.


.. method:: ZipFile.writestr(zinfo_or_arcname, data, compress_type=None, \
                             compresslevel=None)

   Write a file into the archive.  The contents is *data*, which may be either
   a :class:`str` or a :class:`bytes` instance; if it is a :class:`str`,
   it is encoded as UTF-8 first.  *zinfo_or_arcname* is either the file
   name it will be given in the archive, or a :class:`ZipInfo` instance.  If it's
   an instance, at least the filename, date, and time must be given.  If it's a
   name, the date and time is set to the current date and time.
   The archive must be opened with mode ``'w'``, ``'x'`` or ``'a'``.

   If given, *compress_type* overrides the value given for the *compression*
   parameter to the constructor for the new entry, or in the *zinfo_or_arcname*
   (if that is a :class:`ZipInfo` instance). Similarly, *compresslevel* will
   override the constructor if given.

   .. note::

      When passing a :class:`ZipInfo` instance as the *zinfo_or_arcname* parameter,
      the compression method used will be that specified in the *compress_type*
      member of the given :class:`ZipInfo` instance.  By default, the
      :class:`ZipInfo` constructor sets this member to :const:`ZIP_STORED`.

   .. versionchanged:: 3.2
      The *compress_type* argument.

   .. versionchanged:: 3.6
      Calling :meth:`writestr` on a ZipFile created with mode ``'r'`` or
      a closed ZipFile will raise a :exc:`ValueError`.  Previously,
      a :exc:`RuntimeError` was raised.

.. method:: ZipFile.mkdir(zinfo_or_directory, mode=511)

   Create a directory inside the archive.  If *zinfo_or_directory* is a string,
   a directory is created inside the archive with the mode that is specified in
   the *mode* argument. If, however, *zinfo_or_directory* is
   a :class:`ZipInfo` instance then the *mode* argument is ignored.

   The archive must be opened with mode ``'w'``, ``'x'`` or ``'a'``.

   .. versionadded:: 3.11


The following data attributes are also available:

.. attribute:: ZipFile.filename

   Name of the ZIP file.

.. attribute:: ZipFile.debug

   The level of debug output to use.  This may be set from ``0`` (the default, no
   output) to ``3`` (the most output).  Debugging information is written to
   ``sys.stdout``.

.. attribute:: ZipFile.comment

   The comment associated with the ZIP file as a :class:`bytes` object.
   If assigning a comment to a
   :class:`ZipFile` instance created with mode ``'w'``, ``'x'`` or ``'a'``,
   it should be no longer than 65535 bytes.  Comments longer than this will be
   truncated.

.. attribute:: ZipFile.data_offset

   The offset to the start of ZIP data from the beginning of the file. When the
   :class:`ZipFile` is opened in either mode ``'w'`` or ``'x'`` and the
   underlying file does not support ``tell()``, the value will be ``None``
   instead.

   .. versionadded:: 3.14

Path Objects

Construct a Path object from a root zipfile (which may be a :class:`ZipFile` instance or file suitable for passing to the :class:`ZipFile` constructor).

at specifies the location of this Path within the zipfile, e.g. 'dir/file.txt', 'dir/', or ''. Defaults to the empty string, indicating the root.

Note

The :class:`Path` class does not sanitize filenames within the ZIP archive. Unlike the :meth:`ZipFile.extract` and :meth:`ZipFile.extractall` methods, it is the caller's responsibility to validate or sanitize filenames to prevent path traversal vulnerabilities (e.g., filenames containing ".." or absolute paths). When handling untrusted archives, consider resolving filenames using :func:`os.path.abspath` and checking against the target directory with :func:`os.path.commonpath`.

Path objects expose the following features of :mod:`pathlib.Path` objects:

Path objects are traversable using the / operator or joinpath.

.. attribute:: Path.name

   The final path component.

.. method:: Path.open(mode='r', *, pwd, **)

   Invoke :meth:`ZipFile.open` on the current path.
   Allows opening for read or write, text or binary
   through supported modes: 'r', 'w', 'rb', 'wb'.
   Positional and keyword arguments are passed through to
   :class:`io.TextIOWrapper` when opened as text and
   ignored otherwise.
   ``pwd`` is the ``pwd`` parameter to
   :meth:`ZipFile.open`.

   .. versionchanged:: 3.9
      Added support for text and binary modes for open. Default
      mode is now text.

   .. versionchanged:: 3.11.2
      The ``encoding`` parameter can be supplied as a positional argument
      without causing a :exc:`TypeError`. As it could in 3.9. Code needing to
      be compatible with unpatched 3.10 and 3.11 versions must pass all
      :class:`io.TextIOWrapper` arguments, ``encoding`` included, as keywords.

.. method:: Path.iterdir()

   Enumerate the children of the current directory.

.. method:: Path.is_dir()

   Return ``True`` if the current context references a directory.

.. method:: Path.is_file()

   Return ``True`` if the current context references a file.

.. method:: Path.is_symlink()

   Return ``True`` if the current context references a symbolic link.

   .. versionadded:: 3.12

   .. versionchanged:: 3.13
      Previously, ``is_symlink`` would unconditionally return ``False``.

.. method:: Path.exists()

   Return ``True`` if the current context references a file or
   directory in the zip file.

.. data:: Path.suffix

   The last dot-separated portion of the final component, if any.
   This is commonly called the file extension.

   .. versionadded:: 3.11
      Added :data:`Path.suffix` property.

.. data:: Path.stem

   The final path component, without its suffix.

   .. versionadded:: 3.11
      Added :data:`Path.stem` property.

.. data:: Path.suffixes

   A list of the path’s suffixes, commonly called file extensions.

   .. versionadded:: 3.11
      Added :data:`Path.suffixes` property.

.. method:: Path.read_text(*, **)

   Read the current file as unicode text. Positional and
   keyword arguments are passed through to
   :class:`io.TextIOWrapper` (except ``buffer``, which is
   implied by the context).

   .. versionchanged:: 3.11.2
      The ``encoding`` parameter can be supplied as a positional argument
      without causing a :exc:`TypeError`. As it could in 3.9. Code needing to
      be compatible with unpatched 3.10 and 3.11 versions must pass all
      :class:`io.TextIOWrapper` arguments, ``encoding`` included, as keywords.

.. method:: Path.read_bytes()

   Read the current file as bytes.

.. method:: Path.joinpath(*other)

   Return a new Path object with each of the *other* arguments
   joined. The following are equivalent::

   >>> Path(...).joinpath('child').joinpath('grandchild')
   >>> Path(...).joinpath('child', 'grandchild')
   >>> Path(...) / 'child' / 'grandchild'

   .. versionchanged:: 3.10
      Prior to 3.10, ``joinpath`` was undocumented and accepted
      exactly one parameter.

The :pypi:`zipp` project provides backports of the latest path object functionality to older Pythons. Use zipp.Path in place of zipfile.Path for early access to changes.

PyZipFile Objects

The :class:`PyZipFile` constructor takes the same parameters as the :class:`ZipFile` constructor, and one additional parameter, optimize.

ZipInfo Objects

Instances of the :class:`ZipInfo` class are returned by the :meth:`.getinfo` and :meth:`.infolist` methods of :class:`ZipFile` objects. Each object stores information about a single member of the ZIP archive.

There is one classmethod to make a :class:`ZipInfo` instance for a filesystem file:

.. classmethod:: ZipInfo.from_file(filename, arcname=None, *, \
                                   strict_timestamps=True)

   Construct a :class:`ZipInfo` instance for a file on the filesystem, in
   preparation for adding it to a zip file.

   *filename* should be the path to a file or directory on the filesystem.

   If *arcname* is specified, it is used as the name within the archive.
   If *arcname* is not specified, the name will be the same as *filename*, but
   with any drive letter and leading path separators removed.

   The *strict_timestamps* argument, when set to ``False``, allows to
   zip files older than 1980-01-01 at the cost of setting the
   timestamp to 1980-01-01.
   Similar behavior occurs with files newer than 2107-12-31,
   the timestamp is also set to the limit.

   .. versionadded:: 3.6

   .. versionchanged:: 3.6.2
      The *filename* parameter accepts a :term:`path-like object`.

   .. versionchanged:: 3.8
      Added the *strict_timestamps* keyword-only parameter.


Instances have the following methods and attributes:

.. method:: ZipInfo.is_dir()

   Return ``True`` if this archive member is a directory.

   This uses the entry's name: directories should always end with ``/``.

   .. versionadded:: 3.6


.. attribute:: ZipInfo.filename

   Name of the file in the archive.


.. attribute:: ZipInfo.date_time

   The time and date of the last modification to the archive member.  This is a
   tuple of six values:

   +-------+--------------------------+
   | Index | Value                    |
   +=======+==========================+
   | ``0`` | Year (>= 1980)           |
   +-------+--------------------------+
   | ``1`` | Month (one-based)        |
   +-------+--------------------------+
   | ``2`` | Day of month (one-based) |
   +-------+--------------------------+
   | ``3`` | Hours (zero-based)       |
   +-------+--------------------------+
   | ``4`` | Minutes (zero-based)     |
   +-------+--------------------------+
   | ``5`` | Seconds (zero-based)     |
   +-------+--------------------------+

   .. note::

      The ZIP file format does not support timestamps before 1980.


.. attribute:: ZipInfo.compress_type

   Type of compression for the archive member.


.. attribute:: ZipInfo.comment

   Comment for the individual archive member as a :class:`bytes` object.


.. attribute:: ZipInfo.extra

   Expansion field data.  The `PKZIP Application Note`_ contains
   some comments on the internal structure of the data contained in this
   :class:`bytes` object.


.. attribute:: ZipInfo.create_system

   System which created ZIP archive.


.. attribute:: ZipInfo.create_version

   PKZIP version which created ZIP archive.


.. attribute:: ZipInfo.extract_version

   PKZIP version needed to extract archive.


.. attribute:: ZipInfo.reserved

   Must be zero.


.. attribute:: ZipInfo.flag_bits

   ZIP flag bits.


.. attribute:: ZipInfo.volume

   Volume number of file header.


.. attribute:: ZipInfo.internal_attr

   Internal attributes.


.. attribute:: ZipInfo.external_attr

   External file attributes.


.. attribute:: ZipInfo.header_offset

   Byte offset to the file header.


.. attribute:: ZipInfo.CRC

   CRC-32 of the uncompressed file.


.. attribute:: ZipInfo.compress_size

   Size of the compressed data.


.. attribute:: ZipInfo.file_size

   Size of the uncompressed file.


.. program:: zipfile

Command-Line Interface

The :mod:`zipfile` module provides a simple command-line interface to interact with ZIP archives.

If you want to create a new ZIP archive, specify its name after the :option:`-c` option and then list the filename(s) that should be included:

$ python -m zipfile -c monty.zip spam.txt eggs.txt

Passing a directory is also acceptable:

$ python -m zipfile -c monty.zip life-of-brian_1979/

If you want to extract a ZIP archive into the specified directory, use the :option:`-e` option:

$ python -m zipfile -e monty.zip target-dir/

For a list of the files in a ZIP archive, use the :option:`-l` option:

$ python -m zipfile -l monty.zip

Command-line options

.. option:: -l <zipfile>
            --list <zipfile>

   List files in a zipfile.

.. option:: -c <zipfile> <source1> ... <sourceN>
            --create <zipfile> <source1> ... <sourceN>

   Create zipfile from source files.

.. option:: -e <zipfile> <output_dir>
            --extract <zipfile> <output_dir>

   Extract zipfile into target directory.

.. option:: -t <zipfile>
            --test <zipfile>

   Test whether the zipfile is valid or not.

.. option:: --metadata-encoding <encoding>

   Specify encoding of member names for :option:`-l`, :option:`-e` and
   :option:`-t`.

   .. versionadded:: 3.11


Decompression pitfalls

The extraction in zipfile module might fail due to some pitfalls listed below.

From file itself

Decompression may fail due to incorrect password / CRC checksum / ZIP format or unsupported compression method / decryption.

File System limitations

Exceeding limitations on different file systems can cause decompression failed. Such as allowable characters in the directory entries, length of the file name, length of the pathname, size of a single file, and number of files, etc.

Resources limitations

The lack of memory or disk volume would lead to decompression failed. For example, decompression bombs (aka ZIP bomb) apply to zipfile library that can cause disk volume exhaustion.

Interruption

Interruption during the decompression, such as pressing control-C or killing the decompression process may result in incomplete decompression of the archive.

Default behaviors of extraction

Not knowing the default extraction behaviors can cause unexpected decompression results. For example, when extracting the same archive twice, it overwrites files without asking.