Thursday, March 13, 2003

HttpHandlers And The IIS Metabase

Our team has recently consolidated a bunch of intranet sites housed on various team members' machines into subwebs on a larger server. I had been hosting one of the sites from my office, and needed a way to redirect all hyperlinks to that particular subweb to a new subweb without affecting the rest of the sites on the machine. ASP.NET provides a rather simple way of doing this:

using System.Web;

namespace Forward {
public class Forwarder : IHttpHandler
{

public Forwarder(){}

public void ProcessRequest(HttpContext context)
{

string subWeb = "http://mymachine/subweb";
string oldWeb = "http://newmachine/newsubweb";

      HttpRequest request = context.Request;
      HttpResponse response = context.Response;

      string newUrl = request.Url.AbsoluteUri.Replace(subWeb,newWeb);
      response.Redirect(newUrl);
      }

    public bool IsReusable
      {
      get { return false; }
      }
    }
}

compiled as forward.dll and placed in the subweb's bin/ directory, with the following added to the Web.config:

Funny enough, this only worked for paths like http://mymachine/subweb/foo.aspx, since paths like http://mymachine/subweb/foo.htm were routed directly to the filesystem by IIS and bypassed ASP.NET. I remembered having this problem before, when .NET was still in development, and the trick was to associate the "*" file extension with ASP.NET in the script map. Too bad IIS no longer stores the script map in the registry where it's easy to mess with.

A bit of searching and I found:

http://support.microsoft.com/default.aspx?scid=KB;en-us;q232068#3

I just had to use MetaEdit to find LM/W3SVC/1/ROOT/ScriptMaps and add:

*,C:\WINDOWS\Microsoft.NET\Framework\v1.2.x86dbg\aspnet_isapi.dll,1

and everything is working great now. [Better Living Through Software]

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