Pyramid On App Engine Gets "invalidresponseerror: Header Values Must Be Str, Got 'unicode'

I am using Pyramid 1.3 with the AppEngine 1.6.4 SDK on OS X 10.7.3. I am using Python 2.7 and have threadsafe true in app.yaml. @view_config(route_name='manager_swms', permission='

Solution 1:

so it looks like you are overriding appengine's supported webob which is 1.1.1 on the 2.7 runtime. And pyramid 1.3 depends on webob>=1.2. This is most likely the problem because it was the Blobstore handler stuff that was keeping the sdk held back at webob==0.9 until SDK 1.6.4 was released.

FWIW, this problem is expected to be resolved by SDK 1.6.5 (late April). The only reason I know this is because I was trying to get all this crap resolved when the 2.7 runtime was deemed ready for general use, yet the SDK didn't support it. see this issue for more details.

If possible, I would suggest running it with pyramid 1.2, I know that works fine on appengine. And Just hold off on moving to 1.3 for a few weeks. :)

Solution 2:

Yet another answer... adding a str() fixes the problem, but not the root cause. I spent hours trying to figure out why one particular redirect raised this error while others didn't, before noticing that the URL for the bad redirect was missing the initial "/".

I have no idea why this is the case - possibly an incomplete path is processed differently from a complete one. But if you hit this error try changing:

self.redirect('home.view')

to:

self.redirect('/home.view')