Doc/library/tarfile.rst
!tarfile --- Read and write tar archive files.. module:: tarfile :synopsis: Read and write tar-format archive files.
Source code: :source:Lib/tarfile.py
The :mod:!tarfile module makes it possible to read and write tar
archives, including those using gzip, bz2 and lzma compression.
Use the :mod:zipfile module to read or write :file:.zip files, or the
higher-level functions in :ref:shutil <archiving-operations>.
Some facts and figures:
reads and writes :mod:gzip, :mod:bz2, :mod:compression.zstd, and
:mod:lzma compressed archives if the respective modules are available.
.. The following paragraph should be similar to ../includes/optional-module.rst
If any of these :term:optional modules <optional module> are missing from
your copy of CPython, look for documentation from your distributor (that is,
whoever provided Python to you).
If you are the distributor, see :ref:optional-module-requirements.
read/write support for the POSIX.1-1988 (ustar) format.
read/write support for the GNU tar format including longname and longlink extensions, read-only support for all variants of the sparse extension including restoration of sparse files.
read/write support for the POSIX.1-2001 (pax) format.
handles directories, regular files, hardlinks, symbolic links, fifos, character devices and block devices and is able to acquire and restore file information like timestamp, access permissions and owner.
.. versionchanged:: 3.3
Added support for :mod:lzma compression.
.. versionchanged:: 3.12
Archives are extracted using a :ref:filter <tarfile-extraction-filter>,
which makes it possible to either limit surprising/dangerous features,
or to acknowledge that they are expected and the archive is fully trusted.
.. versionchanged:: 3.14
Set the default extraction filter to :func:data <data_filter>,
which disallows some dangerous features such as links to absolute paths
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
information on :class:TarFile objects and the keyword arguments that are
allowed, see :ref:tarfile-objects.
mode has to be a string of the form 'filemode[:compression]', it defaults
to 'r'. Here is a full list of mode combinations:
+------------------+---------------------------------------------+
| mode | action |
+==================+=============================================+
| 'r' or | Open for reading with transparent |
| 'r:*' | compression (recommended). |
+------------------+---------------------------------------------+
| 'r:' | Open for reading exclusively without |
| | compression. |
+------------------+---------------------------------------------+
| 'r:gz' | Open for reading with gzip compression. |
+------------------+---------------------------------------------+
| 'r:bz2' | Open for reading with bzip2 compression. |
+------------------+---------------------------------------------+
| '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 |
| | if it already exists. |
+------------------+---------------------------------------------+
| 'x:gz' | Create a tarfile with gzip compression. |
| | Raise a :exc:FileExistsError exception |
| | if it already exists. |
+------------------+---------------------------------------------+
| 'x:bz2' | Create a tarfile with bzip2 compression. |
| | Raise a :exc:FileExistsError exception |
| | if it already exists. |
+------------------+---------------------------------------------+
| 'x:xz' | Create a tarfile with lzma compression. |
| | 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 | Open for appending with no compression. The |
| 'a:' | file is created if it does not exist. |
+------------------+---------------------------------------------+
| 'w' or | Open for uncompressed writing. |
| 'w:' | |
+------------------+---------------------------------------------+
| 'w:gz' | Open for gzip compressed writing. |
+------------------+---------------------------------------------+
| 'w:bz2' | Open for bzip2 compressed writing. |
+------------------+---------------------------------------------+
| '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,
:exc:ReadError is raised. Use mode 'r' to avoid this. If a
compression method is not supported, :exc:CompressionError is raised.
If fileobj is specified, it is used as an alternative to a :term:file object
opened in binary mode for name. It is supposed to be at position 0.
For modes 'w:gz', 'x:gz', 'w|gz', 'w:bz2', 'x:bz2',
'w|bz2', :func:tarfile.open accepts the keyword argument
compresslevel (default 6) to specify the compression level of the file.
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
be done on the file. If given, fileobj may be any object that has a
:meth:~io.RawIOBase.read or :meth:~io.RawIOBase.write method
(depending on the mode) that works with bytes.
bufsize specifies the blocksize and defaults to 20 * 512 bytes.
Use this variant in combination with e.g. sys.stdin.buffer, a socket
:term:file object or a tape device.
However, such a :class:TarFile object is limited in that it does
not allow random access, see :ref:tar-examples. The currently
possible modes:
+-------------+--------------------------------------------+
| Mode | Action |
+=============+============================================+
| 'r|*' | Open a stream of tar blocks for reading |
| | with transparent compression. |
+-------------+--------------------------------------------+
| 'r|' | Open a stream of uncompressed tar blocks |
| | for reading. |
+-------------+--------------------------------------------+
| 'r|gz' | Open a gzip compressed stream for |
| | reading. |
+-------------+--------------------------------------------+
| 'r|bz2' | Open a bzip2 compressed stream for |
| | reading. |
+-------------+--------------------------------------------+
| '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 |
| | writing. |
+-------------+--------------------------------------------+
| 'w|bz2' | Open a bzip2 compressed stream for |
| | writing. |
+-------------+--------------------------------------------+
| '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.
.. versionchanged:: 3.6
The name parameter accepts a :term:path-like object.
.. versionchanged:: 3.12 The compresslevel keyword argument also works for streams.
.. versionchanged:: 3.14 The preset keyword argument also works for streams.
.. versionchanged:: 3.15 The default compression level was reduced to 6 (down from 9). It is the default level used by most compression tools and a better tradeoff between speed and performance.
.. class:: TarFile :noindex:
Class for reading and writing tar archives. Do not use this class directly:
use :func:tarfile.open instead. See :ref:tarfile-objects.
.. function:: is_tarfile(name)
Return :const:True if name is a tar archive file, that the :mod:!tarfile
module can read. name may be a :class:str, file, or file-like object.
.. versionchanged:: 3.9 Support for file and file-like objects.
The :mod:!tarfile module defines the following exceptions:
.. exception:: TarError
Base class for all :mod:!tarfile exceptions.
.. exception:: ReadError
Is raised when a tar archive is opened, that either cannot be handled by the
:mod:!tarfile module or is somehow invalid.
.. exception:: CompressionError
Is raised when a compression method is not supported or when the data cannot be decoded properly.
.. exception:: StreamError
Is raised for the limitations that are typical for stream-like :class:TarFile
objects.
.. exception:: ExtractError
Is raised for non-fatal errors when using :meth:TarFile.extract, but only if
:attr:TarFile.errorlevel\ == 2.
.. exception:: HeaderError
Is raised by :meth:TarInfo.frombuf if the buffer it gets is invalid.
.. exception:: FilterError
Base class for members :ref:refused <tarfile-extraction-refuse> by
filters.
.. attribute:: tarinfo
Information about the member that the filter refused to extract,
as :ref:`TarInfo <tarinfo-objects>`.
.. exception:: AbsolutePathError
Raised to refuse extracting a member with an absolute path.
.. exception:: OutsideDestinationError
Raised to refuse extracting a member outside the destination directory.
.. exception:: SpecialFileError
Raised to refuse extracting a special file (e.g. a device or pipe).
.. exception:: AbsoluteLinkError
Raised to refuse extracting a symbolic link with an absolute path.
.. exception:: LinkOutsideDestinationError
Raised to refuse extracting a symbolic link pointing outside the destination directory.
.. exception:: LinkFallbackError
Raised to refuse emulating a link (hard or symbolic) by extracting another
archive member, when that member would be rejected by the filter location.
The exception that was raised to reject the replacement member is available
as :attr:!BaseException.__context__.
.. versionadded:: 3.15
The following constants are available at the module level:
.. data:: ENCODING
The default character encoding: 'utf-8' on Windows, the value returned by
:func:sys.getfilesystemencoding otherwise.
.. data:: REGTYPE AREGTYPE
A regular file :attr:~TarInfo.type.
.. data:: LNKTYPE
A link (inside tarfile) :attr:~TarInfo.type.
.. data:: SYMTYPE
A symbolic link :attr:~TarInfo.type.
.. data:: CHRTYPE
A character special device :attr:~TarInfo.type.
.. data:: BLKTYPE
A block special device :attr:~TarInfo.type.
.. data:: DIRTYPE
A directory :attr:~TarInfo.type.
.. data:: FIFOTYPE
A FIFO special device :attr:~TarInfo.type.
.. data:: CONTTYPE
A contiguous file :attr:~TarInfo.type.
.. data:: GNUTYPE_LONGNAME
A GNU tar longname :attr:~TarInfo.type.
.. data:: GNUTYPE_LONGLINK
A GNU tar longlink :attr:~TarInfo.type.
.. data:: GNUTYPE_SPARSE
A GNU tar sparse file :attr:~TarInfo.type.
Each of the following constants defines a tar archive format that the
:mod:!tarfile module is able to create. See section :ref:tar-formats for
details.
.. data:: USTAR_FORMAT
POSIX.1-1988 (ustar) format.
.. data:: GNU_FORMAT
GNU tar format.
.. data:: PAX_FORMAT
POSIX.1-2001 (pax) format.
.. data:: DEFAULT_FORMAT
The default format for creating archives. This is currently :const:PAX_FORMAT.
.. versionchanged:: 3.8
The default format for new archives was changed to
:const:PAX_FORMAT from :const:GNU_FORMAT.
.. seealso::
Module :mod:zipfile
Documentation of the :mod:zipfile standard module.
:ref:archiving-operations
Documentation of the higher-level archiving facilities provided by the
standard :mod:shutil module.
GNU tar manual, Basic Tar Format <https://www.gnu.org/software/tar/manual/html_node/Standard.html>_
Documentation for tar archive files, including GNU tar extensions.
.. _tarfile-objects:
The :class:TarFile object provides an interface to a tar archive. A tar
archive is a sequence of blocks. An archive member (a stored file) is made up of
a header block followed by data blocks. It is possible to store a file in a tar
archive several times. Each archive member is represented by a :class:TarInfo
object, see :ref:tarinfo-objects for details.
A :class:TarFile object can be used as a context manager in a :keyword:with
statement. It will automatically be closed when the block is completed. Please
note that in the event of an exception an archive opened for writing will not
be finalized; only the internally used file object will be closed. See the
:ref:tar-examples section for a use case.
.. versionadded:: 3.2 Added support for the context management protocol.
.. class:: TarFile(name=None, mode='r', fileobj=None, format=DEFAULT_FORMAT, tarinfo=TarInfo, dereference=False, ignore_zeros=False, encoding=ENCODING, errors='surrogateescape', pax_headers=None, debug=0, errorlevel=1, stream=False)
All following arguments are optional and can be accessed as instance attributes as well.
name is the pathname of the archive. name may be a :term:path-like object.
It can be omitted if fileobj is given.
In this case, the file object's :attr:!name attribute is used if it exists.
mode is either 'r' to read from an existing archive, 'a' to append
data to an existing file, 'w' to create a new file overwriting an existing
one, or 'x' to create a new file only if it does not already exist.
If fileobj is given, it is used for reading or writing data. If it can be determined, mode is overridden by fileobj's mode. fileobj will be used from position 0.
.. note::
*fileobj* is not closed, when :class:`TarFile` is closed.
format controls the archive format for writing. It must be one of the constants
:const:USTAR_FORMAT, :const:GNU_FORMAT or :const:PAX_FORMAT that are
defined at module level. When reading, format will be automatically detected, even
if different formats are present in a single archive.
The tarinfo argument can be used to replace the default :class:TarInfo class
with a different one.
If dereference is :const:False, add symbolic and hard links to the archive. If it
is :const:True, add the content of the target files to the archive. This has no
effect on systems that do not support symbolic links.
If ignore_zeros is :const:False, treat an empty block as the end of the archive.
If it is :const:True, skip empty (and invalid) blocks and try to get as many members
as possible. This is only useful for reading concatenated or damaged archives.
debug can be set from 0 (no debug messages) up to 3 (all debug
messages). The messages are written to sys.stderr.
errorlevel controls how extraction errors are handled,
see :attr:the corresponding attribute <TarFile.errorlevel>.
The encoding and errors arguments define the character encoding to be
used for reading or writing the archive and how conversion errors are going
to be handled. The default settings will work for most users.
See section :ref:tar-unicode for in-depth information.
The pax_headers argument is an optional dictionary of strings which
will be added as a pax global header if format is :const:PAX_FORMAT.
If stream is set to :const:True then while reading the archive info about files
in the archive are not cached, saving memory.
.. versionchanged:: 3.2
Use 'surrogateescape' as the default for the errors argument.
.. versionchanged:: 3.5
The 'x' (exclusive creation) mode was added.
.. versionchanged:: 3.6
The name parameter accepts a :term:path-like object.
.. versionchanged:: 3.13 Add the stream parameter.
.. classmethod:: TarFile.open(...)
Alternative constructor. The :func:tarfile.open function is actually a
shortcut to this classmethod.
.. method:: TarFile.getmember(name)
Return a :class:TarInfo object for member name. If name can not be found
in the archive, :exc:KeyError is raised.
.. note::
If a member occurs more than once in the archive, its last occurrence is assumed
to be the most up-to-date version.
.. method:: TarFile.getmembers()
Return the members of the archive as a list of :class:TarInfo objects. The
list has the same order as the members in the archive.
.. method:: TarFile.getnames()
Return the members as a list of their names. It has the same order as the list
returned by :meth:getmembers.
.. method:: TarFile.list(verbose=True, *, members=None)
Print a table of contents to sys.stdout. If verbose is :const:False,
only the names of the members are printed. If it is :const:True, output
similar to that of :program:ls -l is produced. If optional members is
given, it must be a subset of the list returned by :meth:getmembers.
.. versionchanged:: 3.5 Added the members parameter.
.. method:: TarFile.next()
Return the next member of the archive as a :class:TarInfo object, when
:class:TarFile is opened for reading. Return :const:None if there is no more
available.
.. method:: TarFile.extractall(path=".", members=None, *, numeric_owner=False, filter=None)
Extract all members from the archive to the current working directory or
directory path. If optional members is given, it must be a subset of the
list returned by :meth:getmembers. Directory information like owner,
modification time and permissions are set after all members have been extracted.
This is done to work around two problems: A directory's modification time is
reset each time a file is created in it. And, if a directory's permissions do
not allow writing, extracting files to it will fail.
If numeric_owner is :const:True, the uid and gid numbers from the tarfile
are used to set the owner/group for the extracted files. Otherwise, the named
values from the tarfile are used.
The filter argument specifies how members are modified or rejected
before extraction.
See :ref:tarfile-extraction-filter for details.
It is recommended to set this explicitly only if specific tar features
are required, or as filter='data' to support Python versions with a less
secure default (3.13 and lower).
.. warning::
Never extract archives from untrusted sources without prior inspection.
Since Python 3.14, the default (:func:`data <data_filter>`) will prevent
the most dangerous security issues.
However, it will not prevent *all* unintended or insecure behavior.
Read the :ref:`tarfile-extraction-filter` section for details.
.. versionchanged:: 3.5 Added the numeric_owner parameter.
.. versionchanged:: 3.6
The path parameter accepts a :term:path-like object.
.. versionchanged:: 3.12 Added the filter parameter.
.. versionchanged:: 3.14
The filter parameter now defaults to 'data'.
.. method:: TarFile.extract(member, path="", set_attrs=True, *, numeric_owner=False, filter=None)
Extract a member from the archive to the current working directory, using its
full name. Its file information is extracted as accurately as possible. member
may be a filename or a :class:TarInfo object. You can specify a different
directory using path. path may be a :term:path-like object.
File attributes (owner, mtime, mode) are set unless set_attrs is false.
The numeric_owner and filter arguments are the same as
for :meth:extractall.
.. note::
The :meth:`extract` method does not take care of several extraction issues.
In most cases you should consider using the :meth:`extractall` method.
.. warning::
Never extract archives from untrusted sources without prior inspection.
See the warning for :meth:`extractall` for details.
.. versionchanged:: 3.2 Added the set_attrs parameter.
.. versionchanged:: 3.5 Added the numeric_owner parameter.
.. versionchanged:: 3.6
The path parameter accepts a :term:path-like object.
.. versionchanged:: 3.12 Added the filter parameter.
.. method:: TarFile.extractfile(member)
Extract a member from the archive as a file object. member may be
a filename or a :class:TarInfo object. If member is a regular file or
a link, an :class:io.BufferedReader object is returned. For all other
existing members, :const:None is returned. If member does not appear
in the archive, :exc:KeyError is raised.
.. versionchanged:: 3.3
Return an :class:io.BufferedReader object.
.. versionchanged:: 3.13
The returned :class:io.BufferedReader object has the :attr:!mode
attribute which is always equal to 'rb'.
.. attribute:: TarFile.errorlevel :type: int
If errorlevel is 0, errors are ignored when using :meth:TarFile.extract
and :meth:TarFile.extractall.
Nevertheless, they appear as error messages in the debug output when
debug is greater than 0.
If 1 (the default), all fatal errors are raised as :exc:OSError or
:exc:FilterError exceptions. If 2, all non-fatal errors are raised
as :exc:TarError exceptions as well.
Some exceptions, e.g. ones caused by wrong argument types or data corruption, are always raised.
Custom :ref:extraction filters <tarfile-extraction-filter>
should raise :exc:FilterError for fatal errors
and :exc:ExtractError for non-fatal ones.
Note that when an exception is raised, the archive may be partially extracted. It is the user’s responsibility to clean up.
.. attribute:: TarFile.extraction_filter
.. versionadded:: 3.12
The :ref:extraction filter <tarfile-extraction-filter> used
as a default for the filter argument of :meth:~TarFile.extract
and :meth:~TarFile.extractall.
The attribute may be None or a callable.
String names are not allowed for this attribute, unlike the filter
argument to :meth:~TarFile.extract.
If extraction_filter is None (the default), extraction methods
will use the :func:data <data_filter> filter by default.
The attribute may be set on instances or overridden in subclasses.
It also is possible to set it on the TarFile class itself to set a
global default, although, since it affects all uses of tarfile,
it is best practice to only do so in top-level applications or
:mod:site configuration <site>.
To set a global default this way, a filter function needs to be wrapped in
:func:staticmethod to prevent injection of a self argument.
.. versionchanged:: 3.14
The default filter is set to :func:`data <data_filter>`,
which disallows some dangerous features such as links to absolute paths
or paths outside of the destination.
Previously, the default was equivalent to
:func:`fully_trusted <fully_trusted_filter>`.
.. method:: TarFile.add(name, arcname=None, recursive=True, *, filter=None)
Add the file name to the archive. name may be any type of file
(directory, fifo, symbolic link, etc.). If given, arcname specifies an
alternative name for the file in the archive. Directories are added
recursively by default. This can be avoided by setting recursive to
:const:False. Recursion adds entries in sorted order.
If filter is given, it
should be a function that takes a :class:TarInfo object argument and
returns the changed :class:TarInfo object. If it instead returns
:const:None the :class:TarInfo object will be excluded from the
archive. See :ref:tar-examples for an example.
.. versionchanged:: 3.2 Added the filter parameter.
.. versionchanged:: 3.7 Recursion adds entries in sorted order.
.. method:: TarFile.addfile(tarinfo, fileobj=None)
Add the :class:TarInfo object tarinfo to the archive. If tarinfo represents
a non zero-size regular file, the fileobj argument should be a :term:binary file,
and tarinfo.size bytes are read from it and added to the archive. You can
create :class:TarInfo objects directly, or by using :meth:gettarinfo.
.. versionchanged:: 3.13
*fileobj* must be given for non-zero-sized regular files.
.. method:: TarFile.gettarinfo(name=None, arcname=None, fileobj=None)
Create a :class:TarInfo object from the result of :func:os.stat or
equivalent on an existing file. The file is either named by name, or
specified as a :term:file object fileobj with a file descriptor.
name may be a :term:path-like object. If
given, arcname specifies an alternative name for the file in the
archive, otherwise, the name is taken from fileobj’s
:attr:~io.FileIO.name attribute, or the name argument. The name
should be a text string.
You can modify
some of the :class:TarInfo’s attributes before you add it using :meth:addfile.
If the file object is not an ordinary file object positioned at the
beginning of the file, attributes such as :attr:~TarInfo.size may need
modifying. This is the case for objects such as :class:~gzip.GzipFile.
The :attr:~TarInfo.name may also be modified, in which case arcname
could be a dummy string.
.. versionchanged:: 3.6
The name parameter accepts a :term:path-like object.
.. method:: TarFile.close()
Close the :class:TarFile. In write mode, two finishing zero blocks are
appended to the archive.
.. attribute:: TarFile.pax_headers :type: dict
A dictionary containing key-value pairs of pax global headers.
.. _tarinfo-objects:
A :class:TarInfo object represents one member in a :class:TarFile. Aside
from storing all required attributes of a file (like file type, size, time,
permissions, owner etc.), it provides some useful methods to determine its type.
It does not contain the file's data itself.
:class:TarInfo objects are returned by :class:TarFile's methods
:meth:~TarFile.getmember, :meth:~TarFile.getmembers and
:meth:~TarFile.gettarinfo.
Modifying the objects returned by :meth:~TarFile.getmember or
:meth:~TarFile.getmembers will affect all subsequent
operations on the archive.
For cases where this is unwanted, you can use :mod:copy.copy() <copy> or
call the :meth:~TarInfo.replace method to create a modified copy in one step.
Several attributes can be set to None to indicate that a piece of metadata
is unused or unknown.
Different :class:TarInfo methods handle None differently:
~TarFile.extract or :meth:~TarFile.extractall methods will
ignore the corresponding metadata, leaving it set to a default.~TarFile.addfile will fail.~TarFile.list will print a placeholder string... class:: TarInfo(name="")
Create a :class:TarInfo object.
.. classmethod:: TarInfo.frombuf(buf, encoding, errors)
Create and return a :class:TarInfo object from string buffer buf.
Raises :exc:HeaderError if the buffer is invalid.
.. classmethod:: TarInfo.fromtarfile(tarfile)
Read the next member from the :class:TarFile object tarfile and return it as
a :class:TarInfo object.
.. method:: TarInfo.tobuf(format=DEFAULT_FORMAT, encoding=ENCODING, errors='surrogateescape')
Create a string buffer from a :class:TarInfo object. For information on the
arguments see the constructor of the :class:TarFile class.
.. versionchanged:: 3.2
Use 'surrogateescape' as the default for the errors argument.
A TarInfo object has the following public data attributes:
.. attribute:: TarInfo.name :type: str
Name of the archive member.
.. attribute:: TarInfo.size :type: int
Size in bytes.
.. attribute:: TarInfo.mtime :type: int | float
Time of last modification in seconds since the :ref:epoch <epoch>,
as in :attr:os.stat_result.st_mtime.
.. versionchanged:: 3.12
Can be set to ``None`` for :meth:`~TarFile.extract` and
:meth:`~TarFile.extractall`, causing extraction to skip applying this
attribute.
.. attribute:: TarInfo.mode :type: int
Permission bits, as for :func:os.chmod.
.. versionchanged:: 3.12
Can be set to ``None`` for :meth:`~TarFile.extract` and
:meth:`~TarFile.extractall`, causing extraction to skip applying this
attribute.
.. attribute:: TarInfo.type
File type. type is usually one of these constants: :const:REGTYPE,
:const:AREGTYPE, :const:LNKTYPE, :const:SYMTYPE, :const:DIRTYPE,
:const:FIFOTYPE, :const:CONTTYPE, :const:CHRTYPE, :const:BLKTYPE,
:const:GNUTYPE_SPARSE. To determine the type of a :class:TarInfo object
more conveniently, use the is*() methods below.
.. attribute:: TarInfo.linkname :type: str
Name of the target file name, which is only present in :class:TarInfo objects
of type :const:LNKTYPE and :const:SYMTYPE.
For symbolic links (SYMTYPE), the linkname is relative to the directory
that contains the link.
For hard links (LNKTYPE), the linkname is relative to the root of
the archive.
.. attribute:: TarInfo.uid :type: int
User ID of the user who originally stored this member.
.. versionchanged:: 3.12
Can be set to ``None`` for :meth:`~TarFile.extract` and
:meth:`~TarFile.extractall`, causing extraction to skip applying this
attribute.
.. attribute:: TarInfo.gid :type: int
Group ID of the user who originally stored this member.
.. versionchanged:: 3.12
Can be set to ``None`` for :meth:`~TarFile.extract` and
:meth:`~TarFile.extractall`, causing extraction to skip applying this
attribute.
.. attribute:: TarInfo.uname :type: str
User name.
.. versionchanged:: 3.12
Can be set to ``None`` for :meth:`~TarFile.extract` and
:meth:`~TarFile.extractall`, causing extraction to skip applying this
attribute.
.. attribute:: TarInfo.gname :type: str
Group name.
.. versionchanged:: 3.12
Can be set to ``None`` for :meth:`~TarFile.extract` and
:meth:`~TarFile.extractall`, causing extraction to skip applying this
attribute.
.. attribute:: TarInfo.chksum :type: int
Header checksum.
.. attribute:: TarInfo.devmajor :type: int
Device major number.
.. attribute:: TarInfo.devminor :type: int
Device minor number.
.. attribute:: TarInfo.offset :type: int
The tar header starts here.
.. attribute:: TarInfo.offset_data :type: int
The file's data starts here.
.. attribute:: TarInfo.sparse
Sparse member information.
.. attribute:: TarInfo.pax_headers :type: dict
A dictionary containing key-value pairs of an associated pax extended header.
.. method:: TarInfo.replace(name=..., mtime=..., mode=..., linkname=...,
uid=..., gid=..., uname=..., gname=...,
deep=True)
.. versionadded:: 3.12
Return a new copy of the :class:!TarInfo object with the given attributes
changed. For example, to return a TarInfo with the group name set to
'staff', use::
new_tarinfo = old_tarinfo.replace(gname='staff')
By default, a deep copy is made.
If deep is false, the copy is shallow, i.e. pax_headers
and any custom attributes are shared with the original TarInfo object.
A :class:TarInfo object also provides some convenient query methods:
.. method:: TarInfo.isfile()
Return :const:True if the :class:TarInfo object is a regular file.
.. method:: TarInfo.isreg()
Same as :meth:isfile.
.. method:: TarInfo.isdir()
Return :const:True if it is a directory.
.. method:: TarInfo.issym()
Return :const:True if it is a symbolic link.
.. method:: TarInfo.islnk()
Return :const:True if it is a hard link.
.. method:: TarInfo.ischr()
Return :const:True if it is a character device.
.. method:: TarInfo.isblk()
Return :const:True if it is a block device.
.. method:: TarInfo.isfifo()
Return :const:True if it is a FIFO.
.. method:: TarInfo.isdev()
Return :const:True if it is one of character device, block device or FIFO.
.. _tarfile-extraction-filter:
.. versionadded:: 3.12
The tar format is designed to capture all details of a UNIX-like filesystem,
which makes it very powerful.
Unfortunately, the features make it easy to create tar files that have
unintended -- and possibly malicious -- effects when extracted.
For example, extracting a tar file can overwrite arbitrary files in various
ways (e.g. by using absolute paths, .. path components, or symlinks that
affect later members).
In most cases, the full functionality is not needed. Therefore, tarfile supports extraction filters: a mechanism to limit functionality, and thus mitigate some of the security issues.
.. warning::
None of the available filters blocks all dangerous archive features.
Never extract archives from untrusted sources without prior inspection.
See also :ref:tarfile-further-verification.
.. seealso::
:pep:706
Contains further motivation and rationale behind the design.
The filter argument to :meth:TarFile.extract or :meth:~TarFile.extractall
can be:
the string 'fully_trusted': Honor all metadata as specified in the
archive.
Should be used if the user trusts the archive completely, or implements
their own complex verification.
the string 'tar': Honor most tar-specific features (i.e. features of
UNIX-like filesystems), but block features that are very likely to be
surprising or malicious. See :func:tar_filter for details.
the string 'data': Ignore or block most features specific to UNIX-like
filesystems. Intended for extracting cross-platform data archives.
See :func:data_filter for details.
None (default): Use :attr:TarFile.extraction_filter.
If that is also None (the default), the 'data' filter will be used.
.. versionchanged:: 3.14
The default filter is set to :func:`data <data_filter>`.
Previously, the default was equivalent to
:func:`fully_trusted <fully_trusted_filter>`.
A callable which will be called for each extracted member with a
:ref:TarInfo <tarinfo-objects> describing the member and the destination
path to where the archive is extracted (i.e. the same path is used for all
members)::
filter(member: TarInfo, path: str, /) -> TarInfo | None
The callable is called just before each member is extracted, so it can take the current state of the disk into account. It can:
TarInfo object which will be used instead of the metadata
in the archive, orNone, in which case the member will be skipped, or~TarFile.errorlevel.
Note that when extraction is aborted, :meth:~TarFile.extractall may leave
the archive partially extracted. It does not attempt to clean up.Default named filters
The pre-defined, named filters are available as functions, so they can be
reused in custom filters:
.. function:: fully_trusted_filter(member, path)
Return *member* unchanged.
This implements the ``'fully_trusted'`` filter.
.. function:: tar_filter(member, path)
Implements the ``'tar'`` filter.
- Strip leading slashes (``/`` and :data:`os.sep`) from filenames.
- :ref:`Refuse <tarfile-extraction-refuse>` to extract files with absolute
paths (in case the name is absolute
even after stripping slashes, e.g. ``C:/foo`` on Windows).
This raises :class:`~tarfile.AbsolutePathError`.
- :ref:`Refuse <tarfile-extraction-refuse>` to extract files whose absolute
path (after following symlinks) would end up outside the destination.
This raises :class:`~tarfile.OutsideDestinationError`.
- Clear high mode bits (setuid, setgid, sticky) and group/other write bits
(:const:`~stat.S_IWGRP` | :const:`~stat.S_IWOTH`).
Return the modified ``TarInfo`` member.
.. function:: data_filter(member, path)
Implements the ``'data'`` filter.
In addition to what ``tar_filter`` does:
- Normalize link targets (:attr:`TarInfo.linkname`) using
:func:`os.path.normpath`.
Note that this removes internal ``..`` components, which may change the
meaning of the link if the path in :attr:`!TarInfo.linkname` traverses
symbolic links.
- :ref:`Refuse <tarfile-extraction-refuse>` to extract links (hard or soft)
that link to absolute paths, or ones that link outside the destination.
This raises :class:`~tarfile.AbsoluteLinkError` or
:class:`~tarfile.LinkOutsideDestinationError`.
Note that such files are refused even on platforms that do not support
symbolic links.
- :ref:`Refuse <tarfile-extraction-refuse>` to extract device files
(including pipes).
This raises :class:`~tarfile.SpecialFileError`.
- For regular files, including hard links:
- Set the owner read and write permissions
(:const:`~stat.S_IRUSR` | :const:`~stat.S_IWUSR`).
- Remove the group & other executable permission
(:const:`~stat.S_IXGRP` | :const:`~stat.S_IXOTH`)
if the owner doesn’t have it (:const:`~stat.S_IXUSR`).
- For other files (directories), set ``mode`` to ``None``, so
that extraction methods skip applying permission bits.
- Set user and group info (``uid``, ``gid``, ``uname``, ``gname``)
to ``None``, so that extraction methods skip setting it.
Return the modified ``TarInfo`` member.
Note that this filter does not block *all* dangerous archive features.
See :ref:`tarfile-further-verification` for details.
.. versionchanged:: 3.15
Link targets are now normalized.
.. _tarfile-extraction-refuse:
Filter errors
~~~~~~~~~~~~~
When a filter refuses to extract a file, it will raise an appropriate exception,
a subclass of :class:`~tarfile.FilterError`.
This will abort the extraction if :attr:`TarFile.errorlevel` is 1 or more.
With ``errorlevel=0`` the error will be logged and the member will be skipped,
but extraction will continue.
.. _tarfile-further-verification:
Hints for further verification
Even with filter='data', tarfile is not suited for extracting untrusted
files without prior inspection.
Among other issues, the pre-defined filters do not prevent denial-of-service
attacks. Users should do additional checks.
Here is an incomplete list of things to consider:
new temporary directory <tempfile.mkdtemp>
to prevent e.g. exploiting pre-existing links, and to make it easier to
clean up after a failed extraction.Also note that:
Supporting older Python versions
Extraction filters were added to Python 3.12, but may be backported to older
versions as security updates.
To check whether the feature is available, use e.g.
``hasattr(tarfile, 'data_filter')`` rather than checking the Python version.
The following examples show how to support Python versions with and without
the feature.
Note that setting ``extraction_filter`` will affect any subsequent operations.
* Fully trusted archive::
my_tarfile.extraction_filter = (lambda member, path: member)
my_tarfile.extractall()
* Use the ``'data'`` filter if available, but revert to Python 3.11 behavior
(``'fully_trusted'``) if this feature is not available::
my_tarfile.extraction_filter = getattr(tarfile, 'data_filter',
(lambda member, path: member))
my_tarfile.extractall()
* Use the ``'data'`` filter; *fail* if it is not available::
my_tarfile.extractall(filter=tarfile.data_filter)
or::
my_tarfile.extraction_filter = tarfile.data_filter
my_tarfile.extractall()
* Use the ``'data'`` filter; *warn* if it is not available::
if hasattr(tarfile, 'data_filter'):
my_tarfile.extractall(filter='data')
else:
# remove this when no longer needed
warn_the_user('Extracting may be unsafe; consider updating Python')
my_tarfile.extractall()
Stateful extraction filter example
While tarfile's extraction methods take a simple filter callable, custom filters may be more complex objects with an internal state. It may be useful to write these as context managers, to be used like this::
with StatefulFilter() as filter_func:
tar.extractall(path, filter=filter_func)
Such a filter can be written as, for example::
class StatefulFilter:
def __init__(self):
self.file_count = 0
def __enter__(self):
return self
def __call__(self, member, path):
self.file_count += 1
return member
def __exit__(self, *exc_info):
print(f'{self.file_count} files extracted')
.. _tarfile-commandline: .. program:: tarfile
.. versionadded:: 3.4
The :mod:!tarfile module provides a simple command-line interface to interact
with tar archives.
If you want to create a new tar archive, specify its name after the :option:-c
option and then list the filename(s) that should be included:
.. code-block:: shell-session
$ python -m tarfile -c monty.tar spam.txt eggs.txt
Passing a directory is also acceptable:
.. code-block:: shell-session
$ python -m tarfile -c monty.tar life-of-brian_1979/
If you want to extract a tar archive into the current directory, use
the :option:-e option:
.. code-block:: shell-session
$ python -m tarfile -e monty.tar
You can also extract a tar archive into a different directory by passing the directory's name:
.. code-block:: shell-session
$ python -m tarfile -e monty.tar other-dir/
For a list of the files in a tar archive, use the :option:-l option:
.. code-block:: shell-session
$ python -m tarfile -l monty.tar
Command-line options
.. option:: -l <tarfile>
--list <tarfile>
List files in a tarfile.
.. option:: -c <tarfile> <source1> ... <sourceN>
--create <tarfile> <source1> ... <sourceN>
Create tarfile from source files.
.. option:: -e <tarfile> [<output_dir>]
--extract <tarfile> [<output_dir>]
Extract tarfile into the current directory if *output_dir* is not specified.
.. option:: -t <tarfile>
--test <tarfile>
Test whether the tarfile is valid or not.
.. option:: -v, --verbose
Verbose output.
.. option:: --filter <filtername>
Specifies the *filter* for ``--extract``.
See :ref:`tarfile-extraction-filter` for details.
Only string names are accepted (that is, ``fully_trusted``, ``tar``,
and ``data``).
.. _tar-examples:
Examples
--------
Reading examples
~~~~~~~~~~~~~~~~~~~
How to extract an entire tar archive to the current working directory::
import tarfile
tar = tarfile.open("sample.tar.gz")
tar.extractall(filter='data')
tar.close()
How to extract a subset of a tar archive with :meth:`TarFile.extractall` using
a generator function instead of a list::
import os
import tarfile
def py_files(members):
for tarinfo in members:
if os.path.splitext(tarinfo.name)[1] == ".py":
yield tarinfo
tar = tarfile.open("sample.tar.gz")
tar.extractall(members=py_files(tar))
tar.close()
How to read a gzip compressed tar archive and display some member information::
import tarfile
tar = tarfile.open("sample.tar.gz", "r:gz")
for tarinfo in tar:
print(tarinfo.name, "is", tarinfo.size, "bytes in size and is ", end="")
if tarinfo.isreg():
print("a regular file.")
elif tarinfo.isdir():
print("a directory.")
else:
print("something else.")
tar.close()
Writing examples
~~~~~~~~~~~~~~~~
How to create an uncompressed tar archive from a list of filenames::
import tarfile
tar = tarfile.open("sample.tar", "w")
for name in ["foo", "bar", "quux"]:
tar.add(name)
tar.close()
The same example using the :keyword:`with` statement::
import tarfile
with tarfile.open("sample.tar", "w") as tar:
for name in ["foo", "bar", "quux"]:
tar.add(name)
How to create and write an archive to stdout using
:data:`sys.stdout.buffer <sys.stdout>` in the *fileobj* parameter
in :meth:`TarFile.add`::
import sys
import tarfile
with tarfile.open("sample.tar.gz", "w|gz", fileobj=sys.stdout.buffer) as tar:
for name in ["foo", "bar", "quux"]:
tar.add(name)
How to create an archive and reset the user information using the *filter*
parameter in :meth:`TarFile.add`::
import tarfile
def reset(tarinfo):
tarinfo.uid = tarinfo.gid = 0
tarinfo.uname = tarinfo.gname = "root"
return tarinfo
tar = tarfile.open("sample.tar.gz", "w:gz")
tar.add("foo", filter=reset)
tar.close()
.. _tar-formats:
Supported tar formats
---------------------
There are three tar formats that can be created with the :mod:`!tarfile` module:
* The POSIX.1-1988 ustar format (:const:`USTAR_FORMAT`). It supports filenames
up to a length of at best 256 characters and linknames up to 100 characters.
The maximum file size is 8 GiB. This is an old and limited but widely
supported format.
* The GNU tar format (:const:`GNU_FORMAT`). It supports long filenames and
linknames, files bigger than 8 GiB and sparse files. It is the de facto
standard on GNU/Linux systems. :mod:`!tarfile` fully supports the GNU tar
extensions for long names, sparse file support is read-only.
* The POSIX.1-2001 pax format (:const:`PAX_FORMAT`). It is the most flexible
format with virtually no limits. It supports long filenames and linknames, large
files and stores pathnames in a portable way. Modern tar implementations,
including GNU tar, bsdtar/libarchive and star, fully support extended *pax*
features; some old or unmaintained libraries may not, but should treat
*pax* archives as if they were in the universally supported *ustar* format.
It is the current default format for new archives.
It extends the existing *ustar* format with extra headers for information
that cannot be stored otherwise. There are two flavours of pax headers:
Extended headers only affect the subsequent file header, global
headers are valid for the complete archive and affect all following files.
All the data in a pax header is encoded in *UTF-8* for portability reasons.
There are some more variants of the tar format which can be read, but not
created:
* The ancient V7 format. This is the first tar format from Unix Seventh Edition,
storing only regular files and directories. Names must not be longer than 100
characters, there is no user/group name information. Some archives have
miscalculated header checksums in case of fields with non-ASCII characters.
* The SunOS tar extended format. This format is a variant of the POSIX.1-2001
pax format, but is not compatible.
.. _tar-unicode:
Unicode issues
--------------
The tar format was originally conceived to make backups on tape drives with the
main focus on preserving file system information. Nowadays tar archives are
commonly used for file distribution and exchanging archives over networks. One
problem of the original format (which is the basis of all other formats) is
that there is no concept of supporting different character encodings. For
example, an ordinary tar archive created on a *UTF-8* system cannot be read
correctly on a *Latin-1* system if it contains non-*ASCII* characters. Textual
metadata (like filenames, linknames, user/group names) will appear damaged.
Unfortunately, there is no way to autodetect the encoding of an archive. The
pax format was designed to solve this problem. It stores non-ASCII metadata
using the universal character encoding *UTF-8*.
The details of character conversion in :mod:`!tarfile` are controlled by the
*encoding* and *errors* keyword arguments of the :class:`TarFile` class.
*encoding* defines the character encoding to use for the metadata in the
archive. The default value is :func:`sys.getfilesystemencoding` or ``'ascii'``
as a fallback. Depending on whether the archive is read or written, the
metadata must be either decoded or encoded. If *encoding* is not set
appropriately, this conversion may fail.
The *errors* argument defines how characters are treated that cannot be
converted. Possible values are listed in section :ref:`error-handlers`.
The default scheme is ``'surrogateescape'`` which Python also uses for its
file system calls, see :ref:`os-filenames`.
For :const:`PAX_FORMAT` archives (the default), *encoding* is generally not needed
because all the metadata is stored using *UTF-8*. *encoding* is only used in
the rare cases when binary pax headers are decoded or when strings with
surrogate characters are stored.