wfastcgi 2.2 + IIS 8 + Flask 0.10.1 + Python 3.5.1 = error

I am running a flask webapp of which standalone script runs fine. When it is integrated into IIS 8 with wfastcgi we get this error:

Error occurred while reading WSGI handler:

Traceback (most recent call last):
  File "c:\python\python34\lib\site-packages\wfastcgi.py", line 779, in main
    env, handler = read_wsgi_handler(response.physical_path)
  File "c:\python\python34\lib\site-packages\wfastcgi.py", line 621, in read_wsgi_handler
    handler = get_wsgi_handler(os.getenv('WSGI_HANDLER'))
  File "c:\python\python34\lib\site-packages\wfastcgi.py", line 594, in get_wsgi_handler
    handler = handler()
TypeError: __call__() missing 2 required positional arguments: 'environ' and 'start_response'


StdOut: 

StdErr: 

web.config file:

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
  <appSettings>
    <add key="WSGI_HANDLER" value="app.app()" />
    <add key="PYTHONPATH" value="C:\Flaskapp" />
  </appSettings>
  <system.webServer>
    <!--<handlers accessPolicy="Read, Execute, Script" />-->
    <modules runAllManagedModulesForAllRequests="true" />
    <handlers>
            <add name="Python FastCGI" 
            path="*" verb="*" 
            modules="FastCgiModule" 
            scriptProcessor="C:\python\python34\python.exe|c:\python\python34\lib\site-packages\wfastcgi.py" 
            resourceType="Unspecified" requireAccess="Script" />
    </handlers>
  </system.webServer>
</configuration>

How can this be fixed? Thanks.

[chuckmo8]

The major document I read was wfastcgi on pypi: https://pypi.python.org/pypi/wfastcgi

I also googled with these key words “python flask iis”

https://azure.microsoft.com/en-us/documentation/articles/virtual-machines-windows-classic-python-django-web-app/

http://netdot.co/2015/03/09/flask-on-iis/

https://heejune.me/2015/04/22/running-python-flask-on-a-local-iis-not-azure-with-wfastcgi-py/

Most of the examples I have gone through were with blankets in WSGI_HANDLER value. We followed that and failed.

[zooba]

At a guess, your WSGI_HANDLER app setting should be app.app (without the trailing ()). That way, wfastcgi will do:

handler = __import__("app")
handler = getattr(handler, "app")
handler(environ, start_response)

Currently, it’s doing this:

handler = __import__("app")
handler = getattr(handler, "app")
handler = handler()  # Call here is missing arguments
#handler(environ, start_response)  never reached