ISAPIWSGIHelper and generally isapi + wsgi

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Joel B. Mohler

Jan 26, 2015, 10:18:20 AM1/26/15
I'm in the early learning stages for putting a Python web service in a windows environment.  I assume that I want to serve it behind IIS, but there are lots of untested assumptions around this.  I've found and it seems like a good fit -- allows me to stay in IIS-land for the benefit of an organization already familiar with IIS and use Python best practices for the web app.

However, I'm very baffled by the status of isapi-wsgi.  It seems like an abandoned project, but a genuinely useful & used project.  I'm trying to use it in Python 3.4 and I seem very close to success, but had to fix some trivial Python 3 conversions in  Does no one use this in Python 3?  Why not?  Or does everyone just do what I did and fix it themselves?

Why doesn't someone just fork this, fix it for Py2.6-3.4 and get it on PyPI?  Why don't *I* do that?

That was my stream-of-consciousness rambling about my learning process.  This google group appears as likely as anything I've seen to generate useful responses because of .  I'm hoping for a response that clarifies any of the above.

Specific questions:
1)  Is abandoned?
2)  How would I further diagnose "An Error occured while processing your request -- HttpExtensionProc function failed!" when browsing to http://localhost/isapi-wsgi-test/ after running "c:\Python34\Lib\site-packages\ install".

Thanks, Joel

Randy Syring

Jan 26, 2015, 11:17:40 AM1/26/15
Short answer to most of your questions: I just don't think many people are using isapi-wsgi.  It has it's own mailing list here:!forum/isapi_wsgi-dev

And you will note there are only six posts since 2012.  We are using it in a production environment but only on Python 2.7. 

So, specific answers to your questions:

1) Given the minimal traffic on the dev list and few recent commits ( its likely that the project is stagnant.
2) The cryptic hard-to-troubleshoot error messages always plagued me.  There are some docs somewhere about using pywin32 and "trace" to enable debugging of isapi-wsgi.  I don't remember ever getting that to work well.  That is why I created ISAPIWSGIHelper, so that the error messages were caught and handled properly.

Hope it helps...If I as you I would not be trying to get it to work with Python 3.4 unless I could get someone else to confirm it should work there.  If I had to work with IIS I would either A) stick with Python 2.7 or B) setup an HTTP proxy to something else serving the WSGI app.


Randy Syring
Husband | Father | Redeemed Sinner

"For what does it profit a man to gain the whole world
and forfeit his soul?" (Mark 8:36 ESV)

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