12.5. `tarfile` — 读写 tar 存档文件 ¶

2.3 版新增。

The tarfile module makes it possible to read and write tar archives, including those using gzip or bz2 compression. Use the zipfile module to read or write .zip files, or the higher-level functions in shutil .

Some facts and figures:

读写 gzip and bz2 compressed archives if the respective modules are available.
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 the sparse extension.
read/write support for the POSIX.1-2001 (pax) format.

2.6 版新增。
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.

注意

Handling of multi-stream bzip2 files is not supported. Modules such as bz2file let you overcome this.

tarfile. open ( name=None , mode='r' , fileobj=None , bufsize=10240 , **kwargs ) ¶

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.
`'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.

模式	动作
`'r\|*'`	打开 stream of tar blocks for reading with transparent compression.
`'r\|'`	打开 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.
`'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.

class tarfile. TarFile ¶

tarfile. is_tarfile ( 名称 ) ¶

class tarfile. TarFileCompat ( filename , mode='r' , compression=TAR_PLAIN ) ¶

exception tarfile. TarError ¶

exception tarfile. ReadError ¶

exception tarfile. CompressionError ¶

exception tarfile. StreamError ¶

exception tarfile. ExtractError ¶

The following constants are available at the module level:

tarfile. ENCODING ¶

exception tarfile. HeaderError ¶

Each of the following constants defines a tar archive format that the tarfile module is able to create. See section 支持的 tar 格式了解细节。

tarfile. USTAR_FORMAT ¶

tarfile. GNU_FORMAT ¶

tarfile. PAX_FORMAT ¶

tarfile. DEFAULT_FORMAT ¶

另请参阅

模块 zipfile
存档操作: Documentation of the higher-level archiving facilities provided by the standard shutil 模块。
GNU tar manual, Basic Tar Format: Documentation for tar archive files, including GNU tar extensions.

12.5.1. TarFile 对象 ¶

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 对象了解细节。

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 范例 section for a use case.

New in version 2.7: Added support for the context management protocol.

class tarfile. TarFile ( name=None , mode='r' , fileobj=None , format=DEFAULT_FORMAT , tarinfo=TarInfo , dereference=False , ignore_zeros=False , encoding=ENCODING , errors=None , pax_headers=None , debug=0 , errorlevel=0 )

classmethod TarFile. open ( ... ) ¶

TarFile. getmember ( 名称 ) ¶

TarFile. getmembers ( ) ¶

TarFile. getnames ( ) ¶

TarFile. list ( verbose=True ) ¶

TarFile. next ( ) ¶

TarFile. extractall ( path="." , members=None ) ¶

TarFile. extract ( member , path="" ) ¶

TarFile. extractfile ( member ) ¶

Extract a member from the archive as a file object. member may be a filename or a TarInfo 对象。若 member is a regular file, a file-like object is returned. If member is a link, a file-like object is constructed from the link’s target. If member is none of the above, None 被返回。

注意

The file-like object is read-only. It provides the methods read() , readline() , readlines() , seek() , tell() ，和 close() , and also supports iteration over its lines.

TarFile. add ( 名称 , arcname=None , recursive=True , exclude=None , filter=None ) ¶

添加文件 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 。若 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 )。若 filter is specified it must 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 范例范例。

2.6 版改变：添加 exclude 参数。

2.7 版改变：添加 filter 参数。

Deprecated since version 2.7: The exclude parameter is deprecated, please use the filter parameter instead. For maximum portability, filter should be used as a keyword argument rather than as a positional argument so that code won’t be affected when exclude is ultimately removed.

TarFile. addfile ( tarinfo , fileobj=None ) ¶

添加 TarInfo 对象 tarinfo to the archive. If fileobj 有给定， tarinfo.size bytes are read from it and added to the archive. You can create TarInfo objects directly, or by using gettarinfo() .

注意

On Windows platforms, fileobj should always be opened with mode 'rb' to avoid irritation about the file size.

TarFile. gettarinfo ( name=None , arcname=None , fileobj=None ) ¶

创建 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 自变量。

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 。 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. posix ¶

Setting this to True is equivalent to setting the format 属性为 USTAR_FORMAT , False 相当于 GNU_FORMAT .

2.4 版改变： posix 默认为 False .

Deprecated since version 2.6: 使用 format attribute instead.

TarFile. pax_headers ¶

A dictionary containing key-value pairs of pax global headers.

2.6 版新增。

12.5.2. TarInfo 对象 ¶

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() .

class tarfile. TarInfo ( name="" ) ¶: 创建 TarInfo 对象。

TarInfo. frombuf ( buf ) ¶

Create and return a TarInfo object from string buffer buf .

2.6 版新增：引发 HeaderError if the buffer is invalid..

TarInfo. fromtarfile ( tarfile ) ¶

Read the next member from the TarFile 对象 tarfile and return it as a TarInfo 对象。

2.6 版新增。

TarInfo. tobuf ( format=DEFAULT_FORMAT , encoding=ENCODING , errors='strict' ) ¶

Create a string buffer from a TarInfo object. For information on the arguments see the constructor of the TarFile 类。

2.6 版改变： The arguments were added.

A TarInfo object has the following public data attributes:

TarInfo. 名称 ¶: Name of the archive member.

TarInfo. size ¶: Size in bytes.

TarInfo. mtime ¶: Time of last modification.

TarInfo. mode ¶: Permission bits.

TarInfo. type ¶: 文件类型。 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.

2.6 版新增。

A TarInfo object also provides some convenient query methods:

TarInfo. isfile ( ) ¶: 返回 True 若 Tarinfo object is a regular file.

TarInfo. isreg ( ) ¶: 如同 isfile() .

TarInfo. isdir ( ) ¶: 返回 True if it is a directory.

TarInfo. issym ( ) ¶: 返回 True if it is a symbolic link.

TarInfo. islnk ( ) ¶: 返回 True if it is a hard link.

TarInfo. ischr ( ) ¶: 返回 True if it is a character device.

TarInfo. isblk ( ) ¶: 返回 True if it is a block device.

TarInfo. isfifo ( ) ¶: 返回 True if it is a FIFO.

TarInfo. isdev ( ) ¶: 返回 True if it is one of character device, block device or FIFO.

12.5.3. 范例 ¶

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 语句：

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",
    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()

12.5.4. 支持的 tar 格式 ¶

There are three tar formats that can be created with the tarfile 模块：

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 gigabytes. 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 gigabytes 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 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.

12.5.5. Unicode 问题 ¶

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 (that all other formats are merely variants of) 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. Names (i.e. filenames, linknames, user/group names) containing these characters 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 names using the universal character encoding UTF-8 . When a pax archive is read, these UTF-8 names are converted to the encoding of the local file system.

The details of unicode conversion are controlled by the encoding and errors keyword arguments of the TarFile 类。

默认值对于 encoding is the local character encoding. It is deduced from sys.getfilesystemencoding() and sys.getdefaultencoding() . In read mode, encoding is used exclusively to convert unicode names from a pax archive to strings in the local character encoding. In write mode, the use of encoding depends on the chosen archive format. In case of PAX_FORMAT , input names that contain non-ASCII characters need to be decoded before being stored as UTF-8 strings. The other formats do not make use of encoding unless unicode objects are used as input names. These are converted to 8-bit character strings before they are added to the archive.

The errors argument defines how characters are treated that cannot be converted to or from encoding . Possible values are listed in section 编解码器基类 . In read mode, there is an additional scheme 'utf-8' which means that bad characters are replaced by their UTF-8 representation. This is the default scheme. In write mode the default value for errors is 'strict' to ensure that name information is not altered unnoticed.

12.5. tarfile — 读写 tar 存档文件 ¶

12.5.1. TarFile 对象 ¶

12.5.2. TarInfo 对象 ¶

12.5.3. 范例 ¶

12.5.4. 支持的 tar 格式 ¶

12.5.5. Unicode 问题 ¶

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12.5. `tarfile` — 读写 tar 存档文件 ¶