Override namespace in python

Question

Hi all,

Say there is a folder '/home/user/temp/a40bd22344'. The name is completely random and changes in every iteration.

I need to be able to import this folder in python using fixed name, say 'project'.

I know I can add this folder to sys.path to enable import lookup, but is there a way to replace 'a40bd22344' with 'project'?

May be some clever hacks in init.py?

Added:

It needs to be global - i.e. other scripts loading 'project' via standard

import project

Have to work properly, loading a40bd22344 instead.

Thanks!

Answer 1

Sure, project = __import__('a40bd22344') after sys.path is set properly will just work.

Suppose you want to do it in a function taking the full path as an argument and setting the global import of project properly (as well as magically making import project work afterwards in other modules). Piece of cake:

def weirdimport(fullpath):
  global project

  import os
  import sys
  sys.path.append(os.path.dirname(fullpath))
  try:
      project = __import__(os.path.basename(fullpath))
      sys.modules['project'] = project
  finally:
      del sys.path[-1]

this also leaves sys.path as it found it.

Answer 2

Here's one way to do it, without touching sys.path, using the imp module in python:

import imp

f, filename, desc = imp.find_module('a40bd22344', ['/home/user/temp/'])
project = imp.load_module('a40bd22344', f, filename, desc)

project.some_func()

Here are links to some good documentation on the imp module:

http://docs.python.org/library/imp.html

http://blog.doughellmann.com/2008/02/pymotw-imp.html

Answer 3

You first import it with import:

>>> __import__('temp/a40bd22344')
<module 'temp/a40bd22344' from 'temp/a40bd22344/__init__.py'>

Then you make sure that this module gets known to Python as project:

>>> import sys
>>> sys.modules['project'] = sys.modules.pop('temp/a40bd22344')

After this, anything importing project in the current Python session will get the original module

>>> import project
>>> project
<module 'temp/a40bd22344' from 'temp/a40bd22344/__init__.py'>

This will work also for sub-modules: if you have a foobar.py in the same location you'll get

>>> import project.foobar
>>> project.foobar
<module 'project.foobar' from 'temp/a40bd22344/foobar.py'>

Addendum. Here's what I'm running:

>>> print sys.version
2.5.2 (r252:60911, Jul 31 2008, 17:28:52) 
[GCC 4.2.3 (Ubuntu 4.2.3-2ubuntu7)]