Unable to run appengine-admin on dev_server

Question

I decided to try this project:

http://code.google.com/p/appengine-admin/wiki/QuickStart

For the sake of experiment, I took the demo guestbook that came with the App Engine. The import park is as follows:

import cgi import datetime import wsgiref.handlers from google.appengine.ext import db from google.appengine.api import users from google.appengine.ext import webapp from google.appengine.ext.webapp.util import run_wsgi_app from google import appengine_admin 

The database model and administrator look like this:

 class Greeting(db.Model): author = db.UserProperty() content = db.StringProperty(multiline=True) date = db.DateTimeProperty(auto_now_add=True) class AdminGreeting(appengine_admin.ModelAdmin): model = Greeting listFields = ('author','content','date') editFields = ('author','content','date') appengine_admin.register(AdminGreeting) 

However, I get this exception when trying to start the site:

 File "/home/<username>/python/google_appengine/google/appengine/tools/ dev_appserver.py", line 2875, in _HandleRequest base_env_dict=env_dict) File "/home/<username>/python/google_appengine/google/appengine/tools/dev_appserver.py", line 387, in Dispatch base_env_dict=base_env_dict) File "/home/<username>/python/google_appengine/google/appengine/tools/dev_appserver.py", line 2162, in Dispatch self._module_dict) File "/home/<username>/python/google_appengine/google/appengine/tools/dev_appserver.py", line 2080, in ExecuteCGI reset_modules = exec_script(handler_path, cgi_path, hook) File "/home/<username>/python/google_appengine/google/appengine/tools/dev_appserver.py", line 1976, in ExecuteOrImportScript exec module_code in script_module.__dict__ File "/home/<username>/python/google_appengine/demos/guestbook/guestbook.py", line 37, in <module> appengine_admin.register(AdminGreeting) File "/home/<username>/python/google_appengine/google/appengine_admin/model_register.py", line 120, in register modelAdminInstance = modelAdminClass() File "/home/<username>/python/google_appengine/google/appengine_admin/model_register.py", line 64, in __init__ self._extractProperties(self.listFields, self._listProperties) File "/home/<username>/python/google_appengine/google/appengine_admin/model_register.py", line 76, in _extractProperties storage.append(PropertyWrapper(getattr(self.model, propertyName), propertyName)) File "/home/<username>/python/google_appengine/google/appengine_admin/model_register.py", line 17, in __init__ logging.info("Caching info about property '%s'" % name) File "/usr/lib/python2.6/logging/__init__.py", line 1451, in info root.info(*((msg,)+args), **kwargs) File "/usr/lib/python2.6/logging/__init__.py", line 1030, in info self._log(INFO, msg, args, **kwargs) File "/usr/lib/python2.6/logging/__init__.py", line 1142, in _log record = self.makeRecord(self.name, level, fn, lno, msg, args, exc_info, func, extra) File "/usr/lib/python2.6/logging/__init__.py", line 1117, in makeRecord rv = LogRecord(name, level, fn, lno, msg, args, exc_info, func) File "/usr/lib/python2.6/logging/__init__.py", line 272, in __init__ from multiprocessing import current_process File "/home/<username>/python/google_appengine/google/appengine/tools/dev_appserver.py", line 1089, in decorate return func(self, *args, **kwargs) File "/home/<username>/python/google_appengine/google/appengine/tools/dev_appserver.py", line 1736, in load_module return self.FindAndLoadModule(submodule, fullname, search_path) File "/home/<username>/python/google_appengine/google/appengine/tools/dev_appserver.py", line 1089, in decorate return func(self, *args, **kwargs) File "/home/<username>/python/google_appengine/google/appengine/tools/dev_appserver.py", line 1638, in FindAndLoadModule description) File "/home/<username>/python/google_appengine/google/appengine/tools/dev_appserver.py", line 1089, in decorate return func(self, *args, **kwargs) File "/home/<username>/python/google_appengine/google/appengine/tools/dev_appserver.py", line 1589, in LoadModuleRestricted description) File "/usr/lib/python2.6/multiprocessing/__init__.py", line 83, in <module> import _multiprocessing ImportError: No module named _multiprocessing INFO 2009-04-25 23:34:27,628 dev_appserver.py:2934] "GET / HTTP/1.1" 500 - 

Any idea what could go wrong?

Answer 1

It looks like you're using Python 2.6 (given that some of the messages come from files in / usr / lib / python 2.6 ...!), But the Google App Engine needs Python 2.5 (any 2.5.x will do for any version of x) so you must install and use this to run the App Engine SDK.

Answer 2

The Google App Engine only supports Python 2.5, and you are using a newer version.

From the looks of your directories, you can be on Linux (or is it a Mac?). On, say, Ubuntu, you can "sudo apt-get install python2.5" (it will not affect your Python 2.6 at all), and then instead:

 <path-to-gae>/dev_appserver.py ... 

make

 python2.5 <path-to-gae>/dev_appserver.py ... 

This is better than just blithely developing at 2.6 and deploying at 2.5, which will undoubtedly ask for troubles later.

Answer 3

As others have said, this problem occurs in Python 2.6. I used the fix suggested in this comment in the problem tracker in App Engine :

 A quickfix is to create a file in your app root named `_multiprocessing.py' with the contents: import multiprocessing This way it possible to import the _multiprocessing module. It worked for me using Python 2.6.2 Cheers, Kaji 

Answer 4

To make this work on my local machine (since 2.6) and in GAE, I used:

 import sys, logging if sys.version[:3] == "2.6": logging.logMultiprocessing = 0 

Answer 5

just do the following at the top of your something.py

import registration logging.logMultiprocessing = 0

Answer 6

 import logging logging.logMultiprocessing = 0 

Worked for me

Answer 7

It connected to the fact that I used GAE with python2.6 (maybe 2.6.1), and everything worked just fine.

But now I get the same _multiprocess import error. (python2.6.2).

Answer 8

 import logging logging.logMultiprocessing = 0 

He worked for me. Before uploading to GAE, comment on these lines.