tarfile — Read and write tar archive files¶Source code: Lib/tarfile.py
The tarfile module makes it possible to read and write tar
archives, including those using gzip, bz2 and lzma compression.
Use the zipfile module to read or write .zip files, or the
higher-level functions in shutil.
Some facts and figures:
gzip, bz2 and lzma compressed archives
if the respective modules are available.Changed in version 3.3: Added support for lzma compression.
tarfile.open(name=None, mode='r', fileobj=None, bufsize=10240, **kwargs)¶Return a TarFile object for the pathname name. For detailed
information on TarFile objects and the keyword arguments that are
allowed, see 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 'r:*' |
Open for reading with transparent 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. |
'x' or
'x:' |
Create a tarfile exclusively without
compression.
Raise an FileExistsError exception
if it already exists. |
'x:gz' |
Create a tarfile with gzip compression.
Raise an FileExistsError exception
if it already exists. |
'x:bz2' |
Create a tarfile with bzip2 compression.
Raise an FileExistsError exception
if it already exists. |
'x:xz' |
Create a tarfile with lzma compression.
Raise an 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' or 'w:' |
Open for uncompressed writing. |
'w:gz' |
Open for gzip compressed writing. |
'w:bz2' |
Open for bzip2 compressed writing. |
'w:xz' |
Open for lzma 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,
ReadError is raised. Use mode 'r' to avoid this. If a
compression method is not supported, CompressionError is raised.
If fileobj is specified, it is used as an alternative to a file object opened in binary mode for name. It is supposed to be at position 0.
For modes 'w:gz', 'r:gz', 'w:bz2', 'r:bz2', 'x:gz',
'x:bz2', tarfile.open() accepts the keyword argument
compresslevel (default 9) to specify the compression level of the file.
For special purposes, there is a second format for mode:
'filemode|[compression]'. tarfile.open() will return a 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
read() or write() method (depending on the mode). bufsize
specifies the blocksize and defaults to 20 * 512 bytes. Use this variant
in combination with e.g. sys.stdin, a socket file object or a tape
device. However, such a TarFile object is limited in that it does
not allow random access, see 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. |
'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. |
Changed in version 3.5: The 'x' (exclusive creation) mode was added.
tarfile.TarFile¶Class for reading and writing tar archives. Do not use this class directly:
use tarfile.open() instead. See TarFile Objects.
tarfile.is_tarfile(name)¶Return True if name is a tar archive file, that the tarfile
module can read.
The tarfile module defines the following exceptions:
tarfile.ReadError¶Is raised when a tar archive is opened, that either cannot be handled by the
tarfile module or is somehow invalid.
tarfile.CompressionError¶Is raised when a compression method is not supported or when the data cannot be decoded properly.
tarfile.StreamError¶Is raised for the limitations that are typical for stream-like TarFile
objects.
tarfile.ExtractError¶Is raised for non-fatal errors when using TarFile.extract(), but only if
TarFile.errorlevel== 2.
tarfile.HeaderError¶Is raised by TarInfo.frombuf() if the buffer it gets is invalid.
The following constants are available at the module level:
tarfile.ENCODING¶The default character encoding: 'utf-8' on Windows, the value returned by
sys.getfilesystemencoding() otherwise.
Each of the following constants defines a tar archive format that the
tarfile module is able to create. See section Supported tar formats for
details.
tarfile.USTAR_FORMAT¶POSIX.1-1988 (ustar) format.
tarfile.GNU_FORMAT¶GNU tar format.
tarfile.PAX_FORMAT¶POSIX.1-2001 (pax) format.
tarfile.DEFAULT_FORMAT¶The default format for creating archives. This is currently GNU_FORMAT.
See also
zipfilezipfile standard module.shutil module.The 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 TarInfo
object, see TarInfo Objects for details.
A TarFile object can be used as a context manager in a 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
Examples section for a use case.
New in version 3.2: Added support for the context management protocol.
tarfile.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=0)All following arguments are optional and can be accessed as instance attributes as well.
name is the pathname of the archive. It can be omitted if fileobj is given.
In this case, the file object’s 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 TarFile is closed.
format controls the archive format. It must be one of the constants
USTAR_FORMAT, GNU_FORMAT or PAX_FORMAT that are
defined at module level.
The tarinfo argument can be used to replace the default TarInfo class
with a different one.
If dereference is False, add symbolic and hard links to the archive. If it
is 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 False, treat an empty block as the end of the archive.
If it is 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.
If errorlevel is 0, all errors are ignored when using TarFile.extract().
Nevertheless, they appear as error messages in the debug output, when debugging
is enabled. If 1, all fatal errors are raised as OSError
exceptions. If 2, all non-fatal errors are raised as TarError
exceptions as well.
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 Unicode issues 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 PAX_FORMAT.
Changed in version 3.2: Use 'surrogateescape' as the default for the errors argument.
Changed in version 3.5: The 'x' (exclusive creation) mode was added.
TarFile.open(...)¶Alternative constructor. The tarfile.open() function is actually a
shortcut to this classmethod.
TarFile.getmember(name)¶Return a TarInfo object for member name. If name can not be found
in the archive, 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.
TarFile.getmembers()¶Return the members of the archive as a list of TarInfo objects. The
list has the same order as the members in the archive.
TarFile.getnames()¶Return the members as a list of their names. It has the same order as the list
returned by getmembers().
TarFile.list(verbose=True, *, members=None)¶Print a table of contents to sys.stdout. If verbose is False,
only the names of the members are printed. If it is True, output
similar to that of ls -l is produced. If optional members is
given, it must be a subset of the list returned by getmembers().
Changed in version 3.5: Added the members parameter.
TarFile.next()¶Return the next member of the archive as a TarInfo object, when
TarFile is opened for reading. Return None if there is no more
available.
TarFile.extractall(path=".", members=None, *, numeric_owner=False)¶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 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 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.
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 "..".
Changed in version 3.5: Added the numeric_owner parameter.
TarFile.extract(member, path="", set_attrs=True, *, numeric_owner=False)¶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 TarInfo object. You can specify a different
directory using path. File attributes (owner, mtime, mode) are set unless
set_attrs is false.
If numeric_owner is 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.
Note
The extract() method does not take care of several extraction issues.
In most cases you should consider using the extractall() method.
Warning
See the warning for extractall().
Changed in version 3.2: Added the set_attrs parameter.
Changed in version 3.5: Added the numeric_owner parameter.
TarFile.extractfile(member)¶Extract a member from the archive as a file object. member may be a filename
or a TarInfo object. If member is a regular file or a link, an
io.BufferedReader object is returned. Otherwise, None is
returned.
Changed in version 3.3: Return an io.BufferedReader object.
TarFile.add(name, arcname=None, recursive=True, exclude=None, *, 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
False. If exclude is given, it must be a function that takes one
filename argument and returns a boolean value. Depending on this value the
respective file is either excluded (True) or added
(False). If filter is specified it must be a keyword argument. It
should be a function that takes a TarInfo object argument and
returns the changed TarInfo object. If it instead returns
None the TarInfo object will be excluded from the
archive. See Examples for an example.
Changed in version 3.2: Added the filter parameter.
Deprecated since version 3.2: The exclude parameter is deprecated, please use the filter parameter instead.
TarFile.addfile(tarinfo, fileobj=None)¶Add the TarInfo object tarinfo to the archive. If fileobj is given,
it should be a binary file, and
tarinfo.size bytes are read from it and added to the archive. You can
create TarInfo objects directly, or by using gettarinfo().
TarFile.gettarinfo(name=None, arcname=None, fileobj=None)¶Create a TarInfo object from the result of os.stat() or
equivalent on an existing file. The file is either named by name, or
specified as a file object fileobj with a file descriptor. If
given, arcname specifies an alternative name for the file in the
archive, otherwise, the name is taken from fileobj’s
name attribute, or the name argument. The name
should be a text string.
You can modify
some of the TarInfo’s attributes before you add it using addfile().
If the file object is not an ordinary file object positioned at the
beginning of the file, attributes such as size may need
modifying. This is the case for objects such as GzipFile.
The name may also be modified, in which case arcname
could be a dummy string.
TarFile.close()¶Close the TarFile. In write mode, two finishing zero blocks are
appended to the archive.
TarFile.pax_headers¶A dictionary containing key-value pairs of pax global headers.
A TarInfo object represents one member in a 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.
TarInfo objects are returned by TarFile‘s methods
getmember(), getmembers() and gettarinfo().
TarInfo.frombuf(buf, encoding, errors)¶Create and return a TarInfo object from string buffer buf.
Raises HeaderError if the buffer is invalid.
TarInfo.fromtarfile(tarfile)¶Read the next member from the TarFile object tarfile and return it as
a TarInfo object.
TarInfo.tobuf(format=DEFAULT_FORMAT, encoding=ENCODING, errors='surrogateescape')¶Create a string buffer from a TarInfo object. For information on the
arguments see the constructor of the TarFile class.
Changed in version 3.2: Use 'surrogateescape' as the default for the errors argument.
A TarInfo object has the following public data attributes:
TarInfo.name¶Name of the archive member.
TarInfo.size¶Size in bytes.
TarInfo.mtime¶Time of last modification.
TarInfo.mode¶Permission bits.
TarInfo.type¶File type. type is usually one of these constants: REGTYPE,
AREGTYPE, LNKTYPE, SYMTYPE, DIRTYPE,
FIFOTYPE, CONTTYPE, CHRTYPE, BLKTYPE,
GNUTYPE_SPARSE. To determine the type of a TarInfo object
more conveniently, use the is*() methods below.
TarInfo.linkname¶Name of the target file name, which is only present in TarInfo objects
of type LNKTYPE and SYMTYPE.
TarInfo.uid¶User ID of the user who originally stored this member.
TarInfo.gid¶Group ID of the user who originally stored this member.
TarInfo.uname¶User name.
TarInfo.gname¶Group name.
TarInfo.pax_headers¶A dictionary containing key-value pairs of an associated pax extended header.
A TarInfo object also provides some convenient query methods:
New in version 3.4.
The 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 -c
option and then list the filename(s) that should be included:
$ python -m tarfile -c monty.tar spam.txt eggs.txt
Passing a directory is also acceptable:
$ python -m tarfile -c monty.tar life-of-brian_1979/
If you want to extract a tar archive into the current directory, use
the -e option:
$ python -m tarfile -e monty.tar
You can also extract a tar archive into a different directory by passing the directory’s name:
$ python -m tarfile -e monty.tar other-dir/
For a list of the files in a tar archive, use the -l option:
$ python -m tarfile -l monty.tar
-c <tarfile> <source1> ... <sourceN>¶--create <tarfile> <source1> ... <sourceN>¶Create tarfile from source files.
-e <tarfile> [<output_dir>]¶--extract <tarfile> [<output_dir>]¶Extract tarfile into the current directory if output_dir is not specified.
-v, --verboseVerbose output.
How to extract an entire tar archive to the current working directory:
import tarfile
tar = tarfile.open("sample.tar.gz")
tar.extractall()
tar.close()
How to extract a subset of a tar archive with 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 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 with statement:
import tarfile
with tarfile.open("sample.tar", "w") as tar:
for name in ["foo", "bar", "quux"]:
tar.add(name)
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()
How to create an archive and reset the user information using the filter
parameter in 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()
There are three tar formats that can be created with the tarfile module:
The POSIX.1-1988 ustar format (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 (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. tarfile fully supports the GNU tar
extensions for long names, sparse file support is read-only.
The POSIX.1-2001 pax format (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. However, not all tar
implementations today are able to handle pax archives properly.
The pax format is an extension to the existing ustar format. It uses 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 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 tarfile are controlled by the
encoding and errors keyword arguments of the TarFile class.
encoding defines the character encoding to use for the metadata in the
archive. The default value is 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 Error Handlers.
The default scheme is 'surrogateescape' which Python also uses for its
file system calls, see File Names, Command Line Arguments, and Environment Variables.
In case of PAX_FORMAT archives, 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.