Azure Python website not URL-decoding spaces in URL

Question

I'm deploying a Django website on an Azure website, following the Django Azure tutorial. Everything works fine, except for one URL: my only URL that accepts spaces.

When I request https://mysite.azurewebsites.net/root/path/this%20is%20a%20parameter (and I've checked that the query is sent with %20 - not a space or a double encoding), the PATH_INFO inside Django is actually /root/path/this%20is%20a%20parameter. While in my understanding it should be decoded with spaces instead of %20 - IIS (actually, http.sys) being responsible for the decoding.

It works perfectly with the debug server. But in Azure IIS, since the value is botched, my application crashes.

When using a query parameter (?key=value) there are no problems either (which is logical since IIS does not touch that part).

Inside the access logs, oddly I find plus signs (+) instead of %20 or spaces: GET /root/path/this+is+a+parameter (very odd since + are not legal in that part of the URL, perhaps it's only a logging artifact?)

Finally, I'm not using any form of rewrite - I have directly mapped the FastCGI handler to this URL to avoid any confusion.

<?xml version="1.0"?>
<configuration>
    <appSettings>
        <add key="WSGI_ALT_VIRTUALENV_HANDLER" value="django.core.wsgi.get_wsgi_application()" />
        <add key="WSGI_ALT_VIRTUALENV_ACTIVATE_THIS" value="D:\home\site\wwwroot\env\Scripts\activate_this.py" />
        <add key="WSGI_HANDLER" value="ptvs_virtualenv_proxy.get_virtualenv_handler()" />
        <add key="PYTHONPATH" value="D:\home\site\wwwroot" />
        <add key="DJANGO_SETTINGS_MODULE" value="MYAPP.settings" />   
    </appSettings>
    <system.web>
        <compilation debug="true" targetFramework="4.0" />
        <customErrors mode="Off"/>
    </system.web>
    <system.webServer>
        <handlers>
            <add name="Python FastCGI" path="*" verb="*" modules="FastCgiModule" scriptProcessor="D:\Python27\python.exe|D:\Python27\Scripts\wfastcgi.py" resourceType="Unspecified" requireAccess="Script" />
        </handlers>
    </system.webServer>
</configuration>

Would anyone have encoutered this and be able to retrieve the decoded value? Thanks!

Answer 1

In the end it was a bug in the Azure provided IIS handler for WSGI (a WSGI/FCGI bridge). I've opened a bug in their GitHub