VS2010 development web server does not use integrated-mode HTTP handlers/modules

Question

I am developing an ASP.NET MVC 2 web site, targeted for .NET Framework 4.0, using Visual Studio 2010.

My web.config contains the following code:

<system.webServer>
    <modules runAllManagedModulesForAllRequests="true">
        <add name="XhtmlModule" type="DomenicDenicola.Website.XhtmlModule" />
    </modules>
    <handlers>
        <add name="DotLess" type="dotless.Core.LessCssHttpHandler,dotless.Core" path="*.less" verb="*" />
    </handlers>
</system.webServer>

When I use Build > Publish to put the web site on my local IIS7 instance, it works great.

However, when I use Debug > Start Debugging, neither the HTTP handler nor module are executed on any requests.

Strangely enough, when I put the handler and module <add /> tags back into <system.web /> under <httpHandlers /> and <httpModules />, they work. This seems to imply that the development web server is running in classic mode.

How do I fix this?

Answer 1

You don't. WebDev.WebServer.exe does not and cannot support integrated pipeline.

So, if you have code that cannot be written to perform in both environments you will need to use a local IIS for development.

Basically, system.web is the place to configure webdev server and IIS5-6 handlers and modules. system.webServer is for IIS7 handlers and modules, as you know.

Reference:

Each request in WebDev.WebHost40 (and previous versions) is processed by HttpRuntime.ProcessRequest (which does not support integrated pipeline mode). This is the method used in all three versions of WebHost.WebServer.dll (the core of WebDev.WebServer.exe)

And the word of some dude who is fairly familiar with the inner workings of Cassini/WebDev by virtue of managing this project. ;-)