azure routing

I spent this morning trying to get routing working in an azure asp.net web role (these are basically just asp.net web applications).  I thought I'd be able to use some combination of HttpHandlers and <location> to get the routing happening but alas it wasn't to be.

I remembered that I did some research into asp.net mvc apps a bit ago and remembered that they used routing so I thought I'd be able to rip it directly off that (or use the mvc libraries).  After a little digging around, routing is available to asp.net 3.5 sp1 (which is azure's current platform) just by using the standard libraries.  Actually Michael Kennedy has already posted about azure & routing perfectly - http://www.michaelckennedy.net/blog/2009/05/27/ASPNETRoutingInWindowsAzureUsingWebForms.aspx.

The crux:

• Reference System.Web.Routing and System.Web.Abstractions


• Create a Global.asax in your web role


• Modify your Global.asax like so

protected void Application_Start(object sender, EventArgs e)

{

RegisterRoutes(RouteTable.Routes);

}

public static void RegisterRoutes(RouteCollection routes)

{

var routeHandler = new WebFormRouteHandler<Page>("~/Test.aspx");

routes.Add(new Route("evidence/{environment}", routeHandler));

}

protected void Application_Start(object sender, EventArgs e)
{
RegisterRoutes(RouteTable.Routes);
}

public static void RegisterRoutes(RouteCollection routes)
{
var routeHandler = new WebFormRouteHandler<Page>("~/Test.aspx");routes.Add(new Route("evidence/{environment}", routeHandler));
}

• Create the WebFormRouteHandler

using System.Web;

using System.Web.Compilation;

using System.Web.Routing;

namespace SuperTravio

{

public class WebFormRouteHandler<T> : IRouteHandler where T : IHttpHandler, new()

{

public string VirtualPath { get; set; }

public WebFormRouteHandler(string virtualPath)

{

this.VirtualPath = virtualPath;

}

#region IRouteHandler Members

public IHttpHandler GetHttpHandler(RequestContext requestContext)

{

foreach (var aux in requestContext.RouteData.Values)

{

HttpContext.Current.Items[aux.Key] = aux.Value;

}

return (VirtualPath != null)

? (IHttpHandler)BuildManager.CreateInstanceFromVirtualPath(VirtualPath, typeof(T))

: new T();

}

#endregion

}

}

• Create a Url routing handler that overrides IIS7's default action

using System.Web;

using System.Web.Routing;

namespace Supertravio

{

public class RoutingHandler : UrlRoutingHandler

{

protected override void VerifyAndProcessRequest(IHttpHandler httpHandler, HttpContextBase httpContext)

{

}

}

}

• Update your web.config to use the handler (from Michael's post)

<system.webserver>

<modules runallmanagedmodulesforallrequests="true">

...

<add name="UrlRoutingModule" type="System.Web.Routing.UrlRoutingModule,

System.Web.Routing, Version=3.5.0.0,

Culture=neutral,

PublicKeyToken=31BF3856AD364E35">

</add>

<handlers>

<add name="UrlRoutingHandler" precondition="integratedMode" verb="*" path="UrlRouting.axd" type="Supertravio.RoutingHandler, Supertravio">

</add>

</handlers>

</modules></system.webserver>

You're done!

The only thing now is accessing the routed parts.  So in my example (new Route("evidence/{environment}") I would get the parts from my page using (string)HttpContext.Current.Items["environment"].