12.4. zipfile — 在 ZIP 归档中工作

1.6 新版功能.

源代码： Lib/zipfile.py

ZIP 文件格式是一个常用的归档与压缩标准。 这个模块提供了创建、读取、写入、添加及列出 ZIP 文件的工具。 任何对此模块的进阶使用都将需要理解此格式，其定义参见 PKZIP 应用程序笔记。

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 GByte 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.

这个模块定义了以下内容：

exception zipfile.BadZipfile

The error raised for bad ZIP files (old name: zipfile.error).

exception zipfile.LargeZipFile

当 ZIP 文件取药 ZIP64 功能但是未启用时抛出此错误。

class zipfile.ZipFile

用于读写 ZIP 文件的类。 欲了解构造函数的描述，参阅段落 ZipFile 对象。

class zipfile.PyZipFile

用于创建包含 Python 库的 ZIP 归档的类。

class zipfile.ZipInfo([filename[, date_time]])

用于表示档案内一个成员信息的类。 此类的实例会由 ZipFile 对象的 getinfo() 和 infolist() 方法返回。 大多数 zipfile 模块的用户都不必创建它们，只需使用此模块所创建的实例。 filename 应当是档案成员的全名，date_time 应当是包含六个字段的描述最近修改时间的元组；这些字段的描述请参阅 ZipInfo Objects。

zipfile.is_zipfile(filename)

根据文件的 Magic Number，如果 filename 是一个有效的 ZIP 文件则返回 True，否则返回 False。 filename 也可能是一个文件或类文件对象。

在 2.7 版更改: 支持文件或类文件对象。

zipfile.ZIP_STORED

未被压缩的归档成员的数字常数。

zipfile.ZIP_DEFLATED

The numeric constant for the usual ZIP compression method. This requires the zlib module. No other compression methods are currently supported.

参见

PKZIP 应用程序笔记
Phil Katz 编写的 ZIP 文件格式文档，此格式和使用的算法的创建者。
Info-ZIP 主页
有关 Info-ZIP 项目的 ZIP 存档程序和开发库的信息。

12.4.1. ZipFile 对象

class zipfile.ZipFile(file[, mode[, compression[, allowZip64]]])

Open a ZIP file, where file can be either a path to a file (a string) or a file-like object. The mode parameter should be 'r' to read an existing file, 'w' to truncate and write a new file, or 'a' to append to an existing file. If mode is 'a' and file refers to an existing ZIP file, then additional files are added to it. If file does not refer to a ZIP file, then a new ZIP archive is appended to the file. This is meant for adding a ZIP archive to another file (such as python.exe).

在 2.6 版更改: If mode is a and the file does not exist at all, it is created.

compression is the ZIP compression method to use when writing the archive, and should be ZIP_STORED or ZIP_DEFLATED; unrecognized values will cause RuntimeError to be raised. If ZIP_DEFLATED is specified but the zlib module is not available, RuntimeError is also raised. The default is ZIP_STORED. If allowZip64 is True zipfile will create ZIP files that use the ZIP64 extensions when the zipfile is larger than 2 GB. If it is false (the default) zipfile will raise an exception when the ZIP file would require ZIP64 extensions. ZIP64 extensions are disabled by default because the default zip and unzip commands on Unix (the InfoZIP utilities) don’t support these extensions.

在 2.7.1 版更改: If the file is created with mode 'a' or 'w' and then closed without adding any files to the archive, the appropriate ZIP structures for an empty archive will be written to the file.

ZipFile is also a context manager and therefore supports the with statement. In the example, myzip is closed after the with statement’s suite is finished—even if an exception occurs:

with ZipFile('spam.zip', 'w') as myzip:
    myzip.write('eggs.txt')

2.7 新版功能: Added the ability to use ZipFile as a context manager.

ZipFile.close()

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

ZipFile.getinfo(name)

Return a ZipInfo object with information about the archive member name. Calling getinfo() for a name not currently contained in the archive will raise a KeyError.

ZipFile.infolist()

Return a list containing a 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.

ZipFile.namelist()

Return a list of archive members by name.

ZipFile.open(name[, mode[, pwd]])

Extract a member from the archive as a file-like object (ZipExtFile). name is the name of the file in the archive, or a ZipInfo object. The mode parameter, if included, must be one of the following: 'r' (the default), 'U', or 'rU'. Choosing 'U' or 'rU' will enable universal newline support in the read-only object. pwd is the password used for encrypted files. Calling open() on a closed ZipFile will raise a RuntimeError.

注解

The file-like object is read-only and provides the following methods: read(), readline(), readlines(), __iter__(), next().

注解

If the ZipFile was created by passing in a file-like object as the first argument to the constructor, then the object returned by open() shares the ZipFile’s file pointer. Under these circumstances, the object returned by open() should not be used after any additional operations are performed on the ZipFile object. If the ZipFile was created by passing in a string (the filename) as the first argument to the constructor, then open() will create a new file object that will be held by the ZipExtFile, allowing it to operate independently of the ZipFile.

注解

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

2.6 新版功能.

ZipFile.extract(member[, path[, pwd]])

Extract a member from the archive to the current working directory; member must be its full name or a 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 ZipInfo object. pwd is the password used for encrypted files.

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

2.6 新版功能.

注解

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 (_).

ZipFile.extractall([path[, members[, pwd]]])

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 namelist(). pwd is the password used for encrypted files.

警告

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 "..".

在 2.7.4 版更改: The zipfile module attempts to prevent that. See extract() note.

2.6 新版功能.

ZipFile.printdir()

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

ZipFile.setpassword(pwd)

Set pwd as default password to extract encrypted files.

2.6 新版功能.

ZipFile.read(name[, pwd])

Return the bytes of the file name in the archive. name is the name of the file in the archive, or a ZipInfo object. The archive must be open for read or append. pwd is the password used for encrypted files and, if specified, it will override the default password set with setpassword(). Calling read() on a closed ZipFile will raise a RuntimeError.

在 2.6 版更改: pwd was added, and name can now be a ZipInfo object.

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. Calling testzip() on a closed ZipFile will raise a RuntimeError.

ZipFile.write(filename[, arcname[, compress_type]])

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. The archive must be open with mode 'w' or 'a' – calling write() on a ZipFile created with mode 'r' will raise a RuntimeError. Calling write() on a closed ZipFile will raise a RuntimeError.

注解

There is no official file name encoding for ZIP files. If you have unicode file names, you must convert them to byte strings in your desired encoding before passing them to write(). WinZip interprets all file names as encoded in CP437, also known as DOS Latin.

注解

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

注解

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.

ZipFile.writestr(zinfo_or_arcname, bytes[, compress_type])

Write the string bytes to the archive; zinfo_or_arcname is either the file name it will be given in the archive, or a 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' or 'a' – calling writestr() on a ZipFile created with mode 'r' will raise a RuntimeError. Calling writestr() on a closed ZipFile will raise a RuntimeError.

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 ZipInfo instance).

注解

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

在 2.7 版更改: The compress_type argument.

The following data attributes are also available:

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.

ZipFile.comment

The comment text associated with the ZIP file. If assigning a comment to a ZipFile instance created with mode ‘a’ or ‘w’, this should be a string no longer than 65535 bytes. Comments longer than this will be truncated in the written archive when close() is called.

12.4.2. PyZipFile Objects

The PyZipFile constructor takes the same parameters as the ZipFile constructor. Instances have one method in addition to those of ZipFile objects.

PyZipFile.writepy(pathname[, basename])

Search for files *.py and add the corresponding file to the archive. The corresponding file is a *.pyo file if available, else a *.pyc file, compiling if necessary. If the pathname is a file, the filename must end with .py, and just the (corresponding *.py[co]) file is added at the top level (no path information). If the pathname is a file that does not end with .py, a RuntimeError will be raised. If it is a directory, and the directory is not a package directory, then all the files *.py[co] are added at the top level. If the directory is a package directory, then all *.py[co] are added under the package name as a file path, and if any subdirectories are package directories, all of these are added recursively. basename is intended for internal use only. The writepy() method makes archives with file names like this:

string.pyc                                # Top level name
test/__init__.pyc                         # Package directory
test/test_support.pyc                          # Module test.test_support
test/bogus/__init__.pyc                   # Subpackage directory
test/bogus/myfile.pyc                     # Submodule test.bogus.myfile

12.4.3. ZipInfo Objects

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

Instances have the following attributes:

ZipInfo.filename

Name of the file in the archive.

ZipInfo.date_time

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

索引 值
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)

注解

The ZIP file format does not support timestamps before 1980.

ZipInfo.compress_type

Type of compression for the archive member.

ZipInfo.comment

Comment for the individual archive member.

ZipInfo.extra

Expansion field data. The PKZIP Application Note contains some comments on the internal structure of the data contained in this string.

ZipInfo.create_system

System which created ZIP archive.

ZipInfo.create_version

PKZIP version which created ZIP archive.

ZipInfo.extract_version

PKZIP version needed to extract archive.

ZipInfo.reserved

必须为零。

ZipInfo.flag_bits

ZIP 标志位。

ZipInfo.volume

Volume number of file header.

ZipInfo.internal_attr

Internal attributes.

ZipInfo.external_attr

External file attributes.

ZipInfo.header_offset

Byte offset to the file header.

ZipInfo.CRC

CRC-32 of the uncompressed file.

ZipInfo.compress_size

Size of the compressed data.

ZipInfo.file_size

Size of the uncompressed file.

12.4.4. 命令行界面

The 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 -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 -e option:

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

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

$ python -m zipfile -l monty.zip

12.4.4.1. Command-line options

-l <zipfile>

List files in a zipfile.

-c <zipfile> <source1> ... <sourceN>

Create zipfile from source files.

-e <zipfile> <output_dir>

Extract zipfile into target directory.

-t <zipfile>

Test whether the zipfile is valid or not.