python - import error: 'No module named' *does* exist

Question

I am getting this stack trace when I start pyramid pserve:

% python $(which pserve) ../etc/development.ini
Traceback (most recent call last):
  File "/home/hughdbrown/.local/bin/pserve", line 9, in <module>
    load_entry_point('pyramid==1.5', 'console_scripts', 'pserve')()
  File "/home/hughdbrown/.virtualenvs/ponder/local/lib/python2.7/site-packages/pyramid-1.5-py2.7.egg/pyramid/scripts/pserve.py", line 51, in main
    return command.run()
  File "/home/hughdbrown/.virtualenvs/ponder/local/lib/python2.7/site-packages/pyramid-1.5-py2.7.egg/pyramid/scripts/pserve.py", line 316, in run
    global_conf=vars)
  File "/home/hughdbrown/.virtualenvs/ponder/local/lib/python2.7/site-packages/pyramid-1.5-py2.7.egg/pyramid/scripts/pserve.py", line 340, in loadapp
    return loadapp(app_spec, name=name, relative_to=relative_to, **kw)
  File "/home/hughdbrown/.virtualenvs/ponder/lib/python2.7/site-packages/PasteDeploy-1.5.2-py2.7.egg/paste/deploy/loadwsgi.py", line 247, in loadapp
    return loadobj(APP, uri, name=name, **kw)
  File "/home/hughdbrown/.virtualenvs/ponder/lib/python2.7/site-packages/PasteDeploy-1.5.2-py2.7.egg/paste/deploy/loadwsgi.py", line 271, in loadobj
    global_conf=global_conf)
  File "/home/hughdbrown/.virtualenvs/ponder/lib/python2.7/site-packages/PasteDeploy-1.5.2-py2.7.egg/paste/deploy/loadwsgi.py", line 296, in loadcontext
    global_conf=global_conf)
  File "/home/hughdbrown/.virtualenvs/ponder/lib/python2.7/site-packages/PasteDeploy-1.5.2-py2.7.egg/paste/deploy/loadwsgi.py", line 320, in _loadconfig
    return loader.get_context(object_type, name, global_conf)
  File "/home/hughdbrown/.virtualenvs/ponder/lib/python2.7/site-packages/PasteDeploy-1.5.2-py2.7.egg/paste/deploy/loadwsgi.py", line 454, in get_context
    section)
  File "/home/hughdbrown/.virtualenvs/ponder/lib/python2.7/site-packages/PasteDeploy-1.5.2-py2.7.egg/paste/deploy/loadwsgi.py", line 476, in _context_from_use
    object_type, name=use, global_conf=global_conf)
  File "/home/hughdbrown/.virtualenvs/ponder/lib/python2.7/site-packages/PasteDeploy-1.5.2-py2.7.egg/paste/deploy/loadwsgi.py", line 406, in get_context
    global_conf=global_conf)
  File "/home/hughdbrown/.virtualenvs/ponder/lib/python2.7/site-packages/PasteDeploy-1.5.2-py2.7.egg/paste/deploy/loadwsgi.py", line 296, in loadcontext
    global_conf=global_conf)
  File "/home/hughdbrown/.virtualenvs/ponder/lib/python2.7/site-packages/PasteDeploy-1.5.2-py2.7.egg/paste/deploy/loadwsgi.py", line 337, in _loadfunc
    return loader.get_context(object_type, name, global_conf)
  File "/home/hughdbrown/.virtualenvs/ponder/lib/python2.7/site-packages/PasteDeploy-1.5.2-py2.7.egg/paste/deploy/loadwsgi.py", line 681, in get_context
    obj = lookup_object(self.spec)
  File "/home/hughdbrown/.virtualenvs/ponder/lib/python2.7/site-packages/PasteDeploy-1.5.2-py2.7.egg/paste/deploy/util.py", line 68, in lookup_object
    module = __import__(parts)
  File "/home/hughdbrown/.virtualenvs/ponder/local/lib/python2.7/site-packages/ponder-0.0.40-py2.7.egg/ponder/server/__init__.py", line 10, in <module>
    from ponder.server.views import Endpoints, route
ImportError: No module named views

This works fine from a python REPL:

% python
Python 2.7.5+ (default, Feb 27 2014, 19:37:08) 
[GCC 4.8.1] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from ponder.server.views import Endpoints, route
>>> 

and from a command line import:

% python -c "from ponder.server.views import Endpoints, route"

An abridged tree output shows what I am working with:

% tree
├── __init__.py
├── ponder
│?? ├── __init__.py
│?? ├── server
│?? │?? ├── __init__.py
│?? │?? └── views
│?? │??     ├── environment_templates.py
│?? │??     ├── groups.py
│?? │??     ├── __init__.py
│?? │??     ├── instances.py
│?? │??     ├── tasks.py
│?? │??     └── users.py

My PYTHONPATH is set to the root of this tree:

% echo $PYTHONPATH
/home/hughdbrown/workspace/ept/ponder/lib

I am running this in a virtualenv that uses python 2.7. I have had this working off and on today but I can't figure out where the problem is. For one thing, the __init__.py seems to be okay with some imports that come just before:

from .database import get_db
from .config import parser
from .views import Endpoints, route

(I changed the last line to an absolute import. No luck.)

Things that I have tried:

1. Rebuilding virtualenv

2. Setting PYTHONPATH

3. Using absolute paths in code

4. Looking for circular imports

I am open to further suggestions in how to debug this error.

---

So the mistake I made was to look only at the source tree. The problem was really in the runtime environment, in my virtualenv. And when I looked there, I found that the desired files were not being installed. The problem, at root, was the setup.py.

Answer 1

I set the PYTHONPATH to '.' and that solved it for me.

export PYTHONPATH='.'

For a one-liner you could as easily do:

PYTHONPATH='.' your_python_script

These commands are expected to be run in a terminal