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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 <just@letterror.com>

Source code: :source:`Lib/zipimport.py`

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.

.. versionchanged:: 3.8
   Previously, ZIP archives with an archive comment were 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

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

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.

Examples

Here is an example that imports a module from a ZIP archive - note that the :mod:`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'