Installing a Module on Heroku - django

Question

I'm deploying something that has been running on my local and realized when I deployed that the module I was using wasn't installed on Heroku, thus I was getting an error like this:
...
from PIL import Image
ImportError: No module named PIL
I've tried:
heroku run pip install PIL
but I'm getting this:
ImportError: No module named setuptools.command
edit
So, I went to the heroku setup and mimicked the steps to install django and postgres. Essentially, I activated the environment and then ran
pip install PIL
This seemed to be doing the trick, I got a lot of readout and then it ended with a confirmation that PIL had been installed. But then again, it said it couldn't find PIL when I ran the new file.

Answer 1

Every command you run on Heroku is run in an isolated and ephemeral environment — any changes you make during heroku run are thrown away immediately when the processes completes.
To make PIL available to your application, you need to add it to requirements.txt instead.

Answer 2

Sometimes PIL package is added in your path but it's somewhere else than in site-packages. In this case you will be able to just import Image.
To make sure try something like this:
>>> import sys
>>> sys.path
[(...), '/usr/lib/python2.7/dist-packages/PIL', (...)]
>>> from PIL import Image
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: No module named PIL
>>> import Image
>>> Image
<module 'Image' from '/usr/lib/python2.7/dist-packages/PIL/Image.pyc'>
In my applications I use code like this:
try:
import Image, ImageDraw, ImageFont
except:
from PIL import Image, ImageDraw, ImageFont

Answer 3

Are you sure you have followed http://devcenter.heroku.com/articles/django#prerequisites and your virtualenv is loaded?
BTW, I recommend using Pillow instead of PIL.
Introduction
The fork author's goal is to foster packaging improvements via:
Publicized development and solicitation of community support.
Exploration of packaging problems within the fork, most noticably via
adding setuptools support but also via clean up & refactoring of
packaging code. Why a fork?
PIL is currently not setuptools compatible. Please see
http://mail.python.org/pipermail/image-sig/2010-August/006480.html for
a more detailed explanation. Also, PIL's current release/maintenance
schedule is not compatible with the various & frequent packaging
issues that have occured.

Answer 4

Even i was facing the same issue, I spent quite a lot of time.
I tried this
heroku run pip install PIL --app=your-app
error:
Running `pip install PIL` attached to terminal... up, run.1983
Downloading/unpacking PIL
Could not find any downloads that satisfy the requirement PIL
Some externally hosted files were ignored (use --allow-external PIL to allow).
Cleaning up...
No distributions at all found for PIL
Storing debug log for failure in /app/.pip/pip.log
But this helps like a charm :)
heroku run pip install Pillow --app=your-app