Run ASP.NET Development Server "virtual path" as an application

Question

I want to run my new web application with forms authentication under the ASP.NET Development WebServer (Cassini), but not at site root "/" (rather, at the path it will reside in production; "/New").

However, the build process gives the error:

"It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level. This error can be caused by a virtual directory not being configured as an application in IIS. New.MvcWeb\obj\debug\csautoparameterize\original\web.config"

Now, I understand what it is saying. I have forms authentication enabled in my web.config in a virtual directory. The error goes away when I remove the web.config, or remove the "virtual path: /New" debugger configuration, or move debugging from Cassini to IIS and manually create an application at "/New".

But it is only a 'virtual' directory in the mind of the Build System. The path IS application-enabled in a production IIS setting. Also, if I remove the web.config, Cassini will happily publish "http://localhost/New" as an application (for example, Server.MapPath("~") returns my project directory without the "/New" suffix); however I need forms authentication (an application-level web.config parameter) enabled in it.

How I can avoid this build error while retaining my desired features?

More Details

The project is currently configured for "file-system" site development. This and Cassini are supposed to make it easier for my content creators to participate in development and testing with their local copy of VS2010, without having to install IIS on their Windows PCs. I will also one-click publish to my local IIS for testing, then package/publish/deploy to public test, then finally publish to production. In my mind I imagine Cassini being a very helpful part of this whole process.

VS2010, MVC application, file-system site project

Project Settings:
 * ASP.NET 4.0
 * Use Visual Studio Development Server  
 * Virtual Path: /New

web.config snippet:
 <authentication mode="Forms">
   <forms loginUrl="~/../login.html" timeout="30"/>
 </authentication>

Answer 1

I'd generally argue apps should never care if they are running as the root or in a sub-uri. I'd also say that, in 2010, with IIS Express coming, it makes no sense investing any time nor heartache in fighting cassini. That should support your requirements much better.

EDIT FOR MORE DETAILS

Interesting updates about IIS express. We do some of the same things for our design types -- we'd rather they implement the designs rather than the programmers lose hours of their life pursuing individual pixels. We found it easiest to basically treat the designers' machines as essentially continuous integration build agent. They run IIS and build using the same command line build script the CI boxes do. Works surprisingly well. In both cases you have a machine that can't care for itself, so everything needs to be scripted. The IIS bit gets setup once generally as we keep it pretty simple and it rarely needs tweakage with modern versions of .NET. Hope this helps.

Answer 2

So, having learned that Cassini actually does run paths as applications [i.e. Server.MapPath("~") returns the project root folder, and Server.MapPath("/") may not exist], it really becomes strictly a build error.

With a better problem definition, I now see other people also have this error in MVC projects with MvcBuildViews and One-Click-Publish. Here are some articles on how to avoid it:

http://stackoverflow.com/questions/2566215/allowdefinitionmachinetoapplication-error-when-publishing-from-vs2010-but-onl

http://connect.microsoft.com/VisualStudio/feedback/details/556312/mvcbuildviews-does-not-play-well-with-one-click-publish