Python/Django import error os.path

Question

I'm currently working on a Django-Project that amongst others has to read different file-formats. Each format got its own reading-script. The formats to be used depend on a choice, that is why the corresponding scripts are imported at run-time by my admin_view.py. That's done via imp:

module = imp.load_source('lidardaten.datatypes.' + datatype, PATH + datatype + '.py')

Now, my problem is, that i get an ImportError while trying to import the os-module within these scripts saying 'No module named path'.

Environment:

Request Method: POST
Request URL: http://lidardaten/django/lidardata/admin/upload/measurement/add/
Django Version: 1.2.5
Python Version: 2.4.3
Installed Applications:
['django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.sites',
 'django.contrib.messages',
 'django.contrib.admin',
 'lidardata.upload']
Installed Middleware:
('django.middleware.common.CommonMiddleware',
 'django.contrib.sessions.middleware.SessionMiddleware',
 'django.middleware.csrf.CsrfViewMiddleware',
 'django.middleware.csrf.CsrfResponseMiddleware',
 'django.contrib.auth.middleware.AuthenticationMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware')


Traceback:
File "/usr/lib/python2.4/site-packages/django/core/handlers/base.py" in get_response
  100.                     response = callback(request, *callback_args, **callback_kwargs)
File "/s1lidar/u1/mathias/www/lidardata/upload/admin_views.py" in add_measurement
  127.             module = imp.load_source('lidardaten.datatypes.' + datatype, PATH + datatype + '.py')
File "/s1lidar/u1/mathias/www/lidardata/datatypes/polly.py" in ?
  1. import os
File "/usr/lib64/python2.4/os.py" in ?
  133. from os.path import (curdir, pardir, sep, pathsep, defpath, extsep, altsep,

Exception Type: ImportError at /admin/upload/measurement/add/
Exception Value: No module named path

I don't have a problem importing the os-module neither whitin the admin_view.py nor via interpreter. Also importing other modules within the reading-scripts works fine - as long as those modules don't try to import os.

Is it because of importing the scripts with imp.load_source ? Other possibilities? Any suggestion would be skyscraper-highly appreciated!

Answer 1

Rather than using imp , have a look at the magic method __import__ , which can import modules without using filenames. Your code will end up something like:

module_name = 'polly'
module = getattr(__import__('lidardaten.datatypes', globals(), locals(), [module_name]), module_name)