31.4. zipimport — Import modules from Zip archives

2.3 版新加入.

This module adds the ability to import Python modules (*.py, *.py[co]) and packages from ZIP-format archives. It is usually not needed to use the zipimport module explicitly; it is automatically used by the built-in import mechanism for sys.path items that are paths to ZIP archives.

Typically, sys.path is a list of directory names as strings. This module also allows an item of sys.path to be a string naming a ZIP file archive. The ZIP archive can contain a subdirectory structure to support package imports, and a path within the archive can be specified to only import from a subdirectory. For example, the path example.zip/lib/ would only import from the lib/ subdirectory within the archive.

Any files may be present in the ZIP archive, but only files .py and .py[co] are available for import. ZIP import of dynamic modules (.pyd, .so) is disallowed. Note that if an archive only contains .py files, Python will not attempt to modify the archive by adding the corresponding .pyc or .pyo file, meaning that if a ZIP archive doesn’t contain .pyc files, importing may be rather slow.

Using the built-in reload() function will fail if called on a module loaded from a ZIP archive; it is unlikely that reload() would be needed, since this would imply that the ZIP has been altered during runtime.

ZIP archives with an archive comment are currently not supported.

也參考

PKZIP Application Note

Documentation on the ZIP file format by Phil Katz, the creator of the format and algorithms used.

PEP 273 - Import Modules from Zip Archives

Written by James C. Ahlstrom, who also provided an implementation. Python 2.3 follows the specification in PEP 273, but uses an implementation written by Just van Rossum that uses the import hooks described in PEP 302.

PEP 302 - New Import Hooks

The PEP to add the import hooks that help this module work.

This module defines an exception:

exception zipimport.ZipImportError

Exception raised by zipimporter objects. It’s a subclass of ImportError, so it can be caught as ImportError, too.

31.4.1. zipimporter Objects

zipimporter is the class for importing ZIP files.

class zipimport.zipimporter(archivepath)

Create a new zipimporter instance. archivepath must be a path to a ZIP file, or to a specific path within a ZIP file. For example, an archivepath of foo/bar.zip/lib will look for modules in the lib directory inside the ZIP file foo/bar.zip (provided that it exists).

ZipImportError is raised if archivepath doesn’t point to a valid ZIP archive.

find_module(fullname[, path])

Search for a module specified by fullname. fullname must be the fully qualified (dotted) module name. It returns the zipimporter instance itself if the module was found, or None if it wasn’t. The optional path argument is ignored—it’s there for compatibility with the importer protocol.

get_code(fullname)

Return the code object for the specified module. Raise ZipImportError if the module couldn’t be found.

get_data(pathname)

Return the data associated with pathname. Raise IOError if the file wasn’t found.

get_filename(fullname)

Return the value __file__ would be set to if the specified module was imported. Raise ZipImportError if the module couldn’t be found.

2.7 版新加入.

get_source(fullname)

Return the source code for the specified module. Raise ZipImportError if the module couldn’t be found, return None if the archive does contain the module, but has no source for it.

is_package(fullname)

Return True if the module specified by fullname is a package. Raise ZipImportError if the module couldn’t be found.

load_module(fullname)

Load the module specified by fullname. fullname must be the fully qualified (dotted) module name. It returns the imported module, or raises ZipImportError if it wasn’t found.

archive

The file name of the importer’s associated ZIP file, without a possible subpath.

prefix

The subpath within the ZIP file where modules are searched. This is the empty string for zipimporter objects which point to the root of the ZIP file.

The archive and prefix attributes, when combined with a slash, equal the original archivepath argument given to the zipimporter constructor.

31.4.2. Examples

Here is an example that imports a module from a ZIP archive - note that the zipimport module is not explicitly used.

$ unzip -l example.zip
Archive:  example.zip
  Length     Date   Time    Name
 --------    ----   ----    ----
     8467  11-26-02 22:30   jwzthreading.py
 --------                   -------
     8467                   1 file
$ ./python
Python 2.3 (#1, Aug 1 2003, 19:54:32)
>>> import sys
>>> sys.path.insert(0, 'example.zip')  # Add .zip file to front of path
>>> import jwzthreading
>>> jwzthreading.__file__
'example.zip/jwzthreading.py'