What kind of route would I need to provide vanity urls? - asp.net-mvc-3

Question

I'd like to provide my users a vanity url, something like:
www.foo.com/sergio
What kind of route would I need to create?
Imagine I have the following controller and action, how can I map a vanity URL to that controller?
public ActionResult Profile(string username)
{
var model = LoadProfile(username);
return View(model);
}
Here is what I've tried and what happens:
Option A:
Every url is caught in this route, meaning every URL I type directs me towards the Account controller, instead of only foo.com/[USERNAME]. No good.
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
"Profile",
"{username}",
new { controller = "Account", action = "Profile", username = UrlParameter.Optional }
);
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults
);
}
Option B:
Default routes work well, but when trying to visit a profile foo.com/[USERNAME] I get an HTTP 404 error.
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults
);
routes.MapRoute(
"DentistProfile",
"{username}",
new { controller = "Account", action = "Profile", username = UrlParameter.Optional }
);
}

Answer 1

one solution could be using custom route constraint as,
public class VanityUrlContraint : IRouteConstraint
{
private static readonly string[] Controllers =
Assembly.GetExecutingAssembly().GetTypes().Where(x => typeof(IController).IsAssignableFrom(x))
.Select(x => x.Name.ToLower().Replace("controller", "")).ToArray();
public bool Match(HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values,
RouteDirection routeDirection)
{
return !Controllers.Contains(values[parameterName].ToString().ToLower());
}
}
and use it as
routes.MapRoute(
name: "Profile",
url: "{username}",
defaults: new {controller = "Account", action = "Profile"},
constraints: new { username = new VanityUrlContraint() }
);
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
downside of this approach, profile view for usernames same as existing controller name will not work, like if there are usernames like "asset", "location", and "AssetController", "LocationController" exists in project, profile view for "asset", "location" will not work.
hope this helps.

Answer 2

Have you tried:
routes.MapRoute(
"YourRouteName",
"{username}",
new {controller="YourController", action="Profile", username=UrlParameter.Optional}
);
This should trap www.foo.com/{username}. Remember that routes are checked in the order you add them, so you can add
routes.MapRoute(
"default",
"{controller}/{action}/{input}",
new {controller="controller", action="action", input=UrlParameter.Optional}
);
first to maintain the "default" behavior.