Question

I have a Windows Server 2008 R2 (64bits) machine on which I wanted to develop a google AppEngine app.

So I installed Python 2.5.4 from python.org (because the Google SDK said I needed 2.5 and 2.5.6 didn’t have any MSI’s)
Then I installed PIL from http://www.pythonware.com/products/pil/ I used version 1.1.7 for python 2.5
I used the 32-bits versions of both of these.

Then I installed the AppEngine SDK.

Hello-World worked fine, but I wanted to manipulate an image, which didn’t work because I get this stacktrace and a HTTP 500 response:

2010-02-18 11:50:27 Running command: "['C:\\Python25\\pythonw.exe', 'C:\\Program Files 

(x86)\\Google\\google_appengine\\dev_appserver.py', '--admin_console_server=', '--port=8080', 'd:\\imgsvc']"
WARNING  2010-02-18 10:50:29,260 datastore_file_stub.py:623] Could not read datastore data from c:\users\admini~1\appdata\local\temp\dev_appserver.datastore
INFO     2010-02-18 10:50:29,627 dev_appserver_main.py:399] Running application imgsvc on port 8080: http://localhost:8080
ERROR    2010-02-18 10:50:40,058 dev_appserver.py:3217] Exception encountered handling request
Traceback (most recent call last):
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\tools\dev_appserver.py", line 3180, in _HandleRequest
    self._Dispatch(dispatcher, self.rfile, outfile, env_dict)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\tools\dev_appserver.py", line 3123, in _Dispatch
    base_env_dict=env_dict)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\tools\dev_appserver.py", line 515, in Dispatch
    base_env_dict=base_env_dict)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\tools\dev_appserver.py", line 2382, in Dispatch
    self._module_dict)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\tools\dev_appserver.py", line 2292, in ExecuteCGI
    reset_modules = exec_script(handler_path, cgi_path, hook)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\tools\dev_appserver.py", line 2188, in ExecuteOrImportScript
    exec module_code in script_module.__dict__
  File "d:\imgsvc\imgsvc.py", line 7, in <module>
    outputimage = images.resize(inputimage.content, 32, 32)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\api\images\__init__.py", line 625, in resize
    return image.execute_transforms(output_encoding=output_encoding)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\api\images\__init__.py", line 513, in execute_transforms
    response)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\api\apiproxy_stub_map.py", line 78, in MakeSyncCall
    return apiproxy.MakeSyncCall(service, call, request, response)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\api\apiproxy_stub_map.py", line 278, in MakeSyncCall
    rpc.CheckSuccess()
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\api\apiproxy_rpc.py", line 149, in _WaitImpl
    self.request, self.response)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\api\apiproxy_stub.py", line 80, in MakeSyncCall
    method(request, response)
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\api\images\images_stub.py", line 171, in _Dynamic_Transform
    response_value = self._EncodeImage(new_image, request.output())
  File "C:\Program Files (x86)\Google\google_appengine\google\appengine\api\images\images_stub.py", line 193, in _EncodeImage
    image.save(image_string, image_encoding)
  File "C:\Python25\lib\site-packages\PIL\Image.py", line 1439, in save
    save_handler(self, fp, filename)
  File "C:\Python25\lib\site-packages\PIL\PngImagePlugin.py", line 564, in _save
    import ICCProfile
SystemError: Parent module 'PIL' not loaded
INFO     2010-02-18 10:50:40,081 dev_appserver.py:3246] "GET / HTTP/1.1" 500 -

The python script I was trying to run:

from google.appengine.api import urlfetch
from google.appengine.api import images

url = "http://www.brokenwire.net/bw/images/113.png"
inputimage = urlfetch.fetch(url)
if inputimage.status_code == 200:
    outputimage = images.resize(inputimage.content, 32, 32)
    self.response.headers['Content-Type'] = "image/png"
        self.response.out.write(outputimage)

Anybody any idea what is going wrong here?

I also tried this standalone python script, which works fine:

import Image
im = Image.open('filename.png')
im2 = im.resize((100,100), Image.ANTIALIAS)
im2.show()

It seems that it makes a difference which image I use:

url = "http://www.r-stone.net/blogs/ishikawa/uploaded_images/google_appengine-779483.png"

Gives the stacktrace of the question, but

url = "http://www.brokenwire.net/bw/images/113.png"

works without a problem.

Answer 1

This happens when Python can’t find ICCProfile module.
Apperently when using trough GAE instead of an ImportError the importer throws a SystemError, and the function fails.
What i did was to change line 567 in …\Python25\Lib\site-packages\PIL\PngImagePlugin.py
from

except ImportError:

to:

except Exception: