# `zipfile` --- 使用ZIP存档

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。

此模块目前不能处理分卷 ZIP 文件。它可以处理使用 ZIP64 扩展（超过 4 GB 的 ZIP 文件）的 ZIP 文件。它支持解密 ZIP 归档中的加密文件，但是目前不能创建一个加密的文件。解密非常慢，因为它是使用原生 Python 而不是 C 实现的。

这个模块定义了以下内容：

exception `zipfile.``BadZipFile`

  为损坏的 ZIP 文件抛出的错误。

  3.2 版新加入.

exception `zipfile.``BadZipfile`

  `BadZipFile` 的别名，与旧版本 Python 保持兼容性。

  3.2 版後已棄用.

exception `zipfile.``LargeZipFile`

  当 ZIP 文件需要 ZIP64 功能但是未启用时会抛出此错误。

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.``Path`

  用于 zip 文件的兼容 pathlib 的包装器。 详情参见 Path Objects。

  3.8 版新加入.

class `zipfile.``PyZipFile`

  用于创建包含 Python 库的 ZIP 归档的类。

class `zipfile.``ZipInfo`(filename='NoName', date_time=(1980, 1, 1, 0, 0, 0))

  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。

  3.1 版更變: 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`

  常用的 ZIP 压缩方法的数字常数。需要 `zlib` 模块。

`zipfile.``ZIP_BZIP2`

  BZIP2 压缩方法的数字常数。需要 `bz2` 模块。

  3.3 版新加入.

`zipfile.``ZIP_LZMA`

  LZMA 压缩方法的数字常数。需要 `lzma` 模块。

  3.3 版新加入.

  備註

  ZIP 文件格式规范包括自 2001 年以来对 bzip2 压缩的支持，以及自 2006 年以来对 LZMA 压缩的支持。但是，一些工具（包括较旧的 Python 版本）不支持这些压缩方法，并且可能拒绝完全处理 ZIP 文件，或者无法提取单个文件。

也參考

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。

## ZipFile 对象

class `zipfile.``ZipFile`(file, mode='r', compression=ZIP_STORED, allowZip64=True, compresslevel=None, *, strict_timestamps=True)

  打开一个 ZIP 文件，file 为一个指向文件的路径（字符串），一个类文件对象或者一个 path-like object。

  形参 mode 应当为 `'r'` 来读取一个存在的文件，`'w'` 来截断并写入新的文件， `'a'` 来添加到一个存在的文件，或者 `'x'` 来仅新建并写入新的文件。如果 mode 为 `'x'` 并且 file 指向已经存在的文件，则抛出 `FileExistsError`。如果 mode 为 `'a'` 且 file 为已存在的文件，则格外的文件将被加入。如果 file 不指向 ZIP 文件，之后一个新的 ZIP 归档将被追加为此文件。这是为了将 ZIP 归档添加到另一个文件（例如 `python.exe`）。如果 mode 为 `'a'` 并且文件不存在， 则会新建。如果 mode 为 `'r'` 或 `'a'`， 则文件应当可定位。

  compression 是在写入归档时要使用的 ZIP 压缩方法，应为 `ZIP_STORED`, `ZIP_DEFLATED`, `ZIP_BZIP2` 或 `ZIP_LZMA`；不可识别的值将导致引发 `NotImplementedError`。 如果指定了 `ZIP_DEFLATED`, `ZIP_BZIP2` 或 `ZIP_LZMA` 但相应的模块 (`zlib`, `bz2` 或 `lzma`) 不可用，则会引发 `RuntimeError`。 默认值为 `ZIP_STORED`。

  如果 allowZip64 为 `True` (默认值) 则当 zipfile 大于 4 GiB 时 zipfile 将创建使用 ZIP64 扩展的 ZIP 文件。 如果该参数为 `false` 则当 ZIP 文件需要 ZIP64 扩展时 `zipfile` 将引发异常。

  compresslevel 形参控制在将文件写入归档时要使用的压缩等级。 当使用 `ZIP_STORED` 或 `ZIP_LZMA` 时无压缩效果。 当使用 `ZIP_DEFLATED` 时接受整数 `0` 至 `9` (更多信息参见 `zlib`)。 当使用 `ZIP_BZIP2` 时接受整数 `1` 至 `9` (更多信息参见 `bz2`)。

  strict_timestamps 参数在设为 `False` 时允许压缩早于 1980-01-01 的文件，代价时会将时间戳设为 1980-01-01。 类似的行为也会对晚于 2107-12-31 的文件发生，时间戳也会被设为该上限值。

  如果创建文件时使用 `'w'`, `'x'` 或 `'a'` 模式并且未向归档添加任何文件就执行了 `closed`，则会将适当的空归档 ZIP 结构写入文件。

  ZipFile 也是一个上下文管理器，因此支持 `with` 语句。 在这个示例中，myzip 将在 `with` 语句块执行完成之后被关闭 --- 即使是发生了异常:

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

  3.2 版新加入: 添加了将 `ZipFile` 用作上下文管理员的功能。

  3.3 版更變: 添加了对 `bzip2` 和 `lzma` 压缩的支持。

  3.4 版更變: 默认启用 ZIP64 扩展。

  3.5 版更變: 添加了对不可查找数据流的支持。 并添加了对 `'x'` 模式的支持。

  3.6 版更變: 在此之前，对于不可识别的压缩值将引发普通的 `RuntimeError`。

  3.6.2 版更變: file 形参接受一个 path-like object。

  3.7 版更變: 添加了 compresslevel 形参。

  3.8 版新加入: strict_timestamps 仅限关键字参数

`ZipFile.``close`()

  关闭归档文件。 你必须在退出程序之前调用 `close()` 否则将不会写入关键记录数据。

`ZipFile.``getinfo`(name)

  返回一个 `ZipInfo` 对象，其中包含有关归档成员 name 的信息。 针对一个目前并不包含于归档中的名称调用 `getinfo()` 将会引发 `KeyError`。

`ZipFile.``infolist`()

  返回一个列表，其中包含每个归档成员的 `ZipInfo` 对象。 如果是打开一个现有归档则这些对象的排列顺序与它们对应条目在磁盘上的实际 ZIP 文件中的顺序一致。

`ZipFile.``namelist`()

  返回按名称排序的归档成员列表。

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

  以二进制文件类对象的形式访问一个归档成员。 name 可以是归档内某个文件的名称也可以是某个 `ZipInfo` 对象。 如果包含了 mode 形参，则它必须为 `'r'` (默认值) 或 `'w'`。 pwd 为用于解密已加密 ZIP 文件的密码。

  `open()` 也是一个上下文管理器，因此支持 `with` 语句:

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

  如果 mode 为 `'r'` 则文件类对象 (`ZipExtFile`) 将为只读并且提供下列方法: `read()`, `readline()`, `readlines()`, `seek()`, `tell()`, `__iter__()`, `__next__()`。 这些对象可独立于 ZipFile 进行操作。

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

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

  備註

  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.

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

  3.6 版更變: `open()` can now be used to write files into the archive with the `mode='w'` option.

  3.6 版更變: Calling `open()` on a closed ZipFile will raise a `ValueError`. Previously, a `RuntimeError` was raised.

`ZipFile.``extract`(member, path=None, pwd=None)

  Extract a member from the archive to the current working directory; member must be its full name or a `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).

  備註

  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 (`_`).

  3.6 版更變: Calling `extract()` on a closed ZipFile will raise a `ValueError`. Previously, a `RuntimeError` was raised.

  3.6.2 版更變: The path parameter accepts a path-like object.

`ZipFile.``extractall`(path=None, members=None, pwd=None)

  Extract all members from the archive to the current working directory. path specifies a different directory to extract to. members is optional and must be a subset of the list returned by `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 `".."`. This module attempts to prevent that. See `extract()` note.

  3.6 版更變: Calling `extractall()` on a closed ZipFile will raise a `ValueError`. Previously, a `RuntimeError` was raised.

  3.6.2 版更變: The path parameter accepts a path-like object.

`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.

`ZipFile.``read`(name, pwd=None)

  Return the bytes of the file name in the archive. name is the name of the file in the archive, or a `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 ZipFile that uses a compression method other than `ZIP_STORED`, `ZIP_DEFLATED`, `ZIP_BZIP2` or `ZIP_LZMA` will raise a `NotImplementedError`. An error will also be raised if the corresponding compression module is not available.

  3.6 版更變: Calling `read()` on a closed ZipFile will raise a `ValueError`. Previously, a `RuntimeError` was raised.

`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`.

  3.6 版更變: Calling `testzip()` on a closed ZipFile will raise a `ValueError`. Previously, a `RuntimeError` was raised.

`ZipFile.``write`(filename, arcname=None, compress_type=None, compresslevel=None)

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

  備註

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

  備註

  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.

  3.6 版更變: Calling `write()` on a ZipFile created with mode `'r'` or a closed ZipFile will raise a `ValueError`. Previously, a `RuntimeError` was raised.

`ZipFile.``writestr`(zinfo_or_arcname, data, compress_type=None, compresslevel=None)

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

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

  備註

  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`.

  3.2 版更變: The compress_type argument.

  3.6 版更變: Calling `writestr()` on a ZipFile created with mode `'r'` or a closed ZipFile will raise a `ValueError`. Previously, a `RuntimeError` was raised.

The following data attributes are also available:

`ZipFile.``filename`

  Name of the ZIP file.

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

## Path Objects

class `zipfile.``Path`(root, at='')

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

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

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

Path objects are traversable using the `/` operator.

`Path.``name`

  The final path component.

`Path.``open`(*, **)

  Invoke `ZipFile.open()` on the current path. Accepts the same arguments as `ZipFile.open()`.

`Path.``iterdir`()

  Enumerate the children of the current directory.

`Path.``is_dir`()

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

`Path.``is_file`()

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

`Path.``exists`()

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

`Path.``read_text`(*, **)

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

`Path.``read_bytes`()

  Read the current file as bytes.

## PyZipFile Objects

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

class `zipfile.``PyZipFile`(file, mode='r', compression=ZIP_STORED, allowZip64=True, optimize=-1)

  3.2 版新加入: The optimize parameter.

  3.4 版更變: 默认启用 ZIP64 扩展。

  Instances have one method in addition to those of `ZipFile` objects:

  `writepy`(pathname, basename='', filterfunc=None)

    Search for files `*.py` and add the corresponding file to the archive.

    If the optimize parameter to `PyZipFile` was not given or `-1`, the corresponding file is a `*.pyc` file, compiling if necessary.

    If the optimize parameter to `PyZipFile` was `0`, `1` or `2`, only files with that optimization level (see `compile()`) are added to the archive, compiling if necessary.

    If pathname is a file, the filename must end with `.py`, and just the (corresponding `*.pyc`) file is added at the top level (no path information). If 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 `*.pyc` are added at the top level. If the directory is a package directory, then all `*.pyc` are added under the package name as a file path, and if any subdirectories are package directories, all of these are added recursively in sorted order.

    basename is intended for internal use only.

    filterfunc, if given, must be a function taking a single string argument. It will be passed each path (including each individual full file path) before it is added to the archive. If filterfunc returns a false value, the path will not be added, and if it is a directory its contents will be ignored. For example, if our test files are all either in `test` directories or start with the string `test_`, we can use a filterfunc to exclude them:

        >>> zf = PyZipFile('myprog.zip')
        >>> def notests(s):
        ...     fn = os.path.basename(s)
        ...     return (not (fn == 'test' or fn.startswith('test_')))
        >>> zf.writepy('myprog', filterfunc=notests)

    The `writepy()` method makes archives with file names like this:

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

    3.4 版新加入: The filterfunc parameter.

    3.6.2 版更變: The pathname parameter accepts a path-like object.

    3.7 版更變: Recursion sorts directory entries.

## 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.

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

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

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

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

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

  strict_timestamps 参数在设为 `False` 时允许压缩早于 1980-01-01 的文件，代价时会将时间戳设为 1980-01-01。 类似的行为也会对晚于 2107-12-31 的文件发生，时间戳也会被设为该上限值。

  3.6 版新加入.

  3.6.2 版更變: The filename parameter accepts a path-like object.

  3.8 版新加入: strict_timestamps 仅限关键字参数

Instances have the following methods and attributes:

`ZipInfo.``is_dir`()

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

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

  3.6 版新加入.

`ZipInfo.``filename`

  Name of the file in the archive.

`ZipInfo.``date_time`

  上次修改存档成员的时间和日期。这是六个值的元组：

  索引 | 值
  --- | ---
  `0` | Year (>= 1980)
  `1` | 月（1为基数）
  `2` | 月份中的日期（1为基数）
  `3` | 小时（0为基数）
  `4` | 分钟（0为基数）
  `5` | 秒（0为基数）

  備註

  ZIP文件格式不支持1980年以前的时间戳。

`ZipInfo.``compress_type`

  Type of compression for the archive member.

`ZipInfo.``comment`

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

`ZipInfo.``extra`

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

`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.

## 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

### 命令行选项

`-l``<zipfile>`
`--list``<zipfile>`

  List files in a zipfile.

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

  Create zipfile from source files.

`-e``<zipfile> <output_dir>`
`--extract``<zipfile> <output_dir>`

  Extract zipfile into target directory.

`-t``<zipfile>`
`--test``<zipfile>`

  Test whether the zipfile is valid or not.

## Decompression pitfalls

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

### From file itself

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

### File System limitations

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

### Resources limitations

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

### Interruption

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

### Default behaviors of extraction

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