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:mod:`zipimport` --- Import modules from Zip archives

kbe/src/lib/python/Doc/library/zipimport.rst

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:mod:zipimport --- Import modules from Zip archives

.. module:: zipimport :synopsis: support for importing Python modules from ZIP archives.

.. moduleauthor:: Just van Rossum [email protected]


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

Typically, :data:sys.path is a list of directory names as strings. This module also allows an item of :data: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 :file:example.zip/lib/ would only import from the :file:lib/ subdirectory within the archive.

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

ZIP archives with an archive comment are currently not supported.

.. seealso::

PKZIP Application Note <https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT>_ 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:: ZipImportError

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

.. _zipimporter-objects:

zipimporter Objects

:class:zipimporter is the class for importing ZIP files.

.. class:: 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 :file:foo/bar.zip/lib will look for modules in the :file:lib directory inside the ZIP file :file:foo/bar.zip (provided that it exists).

:exc:ZipImportError is raised if archivepath doesn't point to a valid ZIP archive.

.. method:: 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 :const:`None` if it wasn't. The optional
  *path* argument is ignored---it's there for compatibility with the
  importer protocol.

.. method:: get_code(fullname)

  Return the code object for the specified module. Raise
  :exc:`ZipImportError` if the module couldn't be found.

.. method:: get_data(pathname)

  Return the data associated with *pathname*. Raise :exc:`OSError` if the
  file wasn't found.

  .. versionchanged:: 3.3
     :exc:`IOError` used to be raised instead of :exc:`OSError`.

.. method:: get_filename(fullname)

  Return the value ``__file__`` would be set to if the specified module
  was imported. Raise :exc:`ZipImportError` if the module couldn't be
  found.

  .. versionadded:: 3.1

.. method:: get_source(fullname)

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

.. method:: is_package(fullname)

  Return ``True`` if the module specified by *fullname* is a package. Raise
  :exc:`ZipImportError` if the module couldn't be found.

.. method:: 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
  :exc:`ZipImportError` if it wasn't found.

.. attribute:: archive

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

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

.. _zipimport-examples:

Examples

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

.. code-block:: shell-session

$ 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'