Web Api dynamic url

Question

I'd like to have one more parameter in my api, but it's not fixed. In this case {config} can be anything like config1, config2, config1433....

        config.Routes.MapHttpRoute(
            name: "DefaultApi",
            routeTemplate: "api/{config}/{controller}/{id}",
            defaults: new { id = RouteParameter.Optional }
        );

I already tried to get the parameter and remove it from the request uri using a delegate handler, but it doesn't work because the url has been already analyzed.

You don't need to do anything elaborate, it would be pretty limiting if you could only have one parameter named "id". I like to use attribute routing, it is easier to make your routes anything you want. https://docs.microsoft.com/en-us/aspnet/web-api/overview/web-api-routing-and-actions/attribute-routing-in-web-api-2 — Crowcoder, Jan 17 '18 at 20:48
I think it's a different case. This parameter that I want to pass is independent of any controller or action. I don't want to pass it to all controllers or all actions. — Cassio Tavares, Jan 17 '18 at 21:09
With attribute parameters I'll have decorate and read it in all my actions. And all my actions will have to receive this attribute. I want something more generic and earlier in web api stack. That's why I'm trying to use routeTemplate for that. Or, another option could be use it like a sub domain. Something like {config}.myhost.com/api/{controller}/{id} — Cassio Tavares, Jan 17 '18 at 21:33
You know you can map more than one route template? You can map as many as you want. — Crowcoder, Jan 17 '18 at 21:35
Yes, by I need to know the route before. In this case it is dynamic. The configuration comes from another api. And I don't know how many will exist. — Cassio Tavares, Jan 17 '18 at 21:38

score 0 · Answer 1 · answered Jan 18 '18 at 02:08

I found a solution.

First I had to inherit from DefaultHttpControllerSelector. Deriving this class allow you to customize the controller selection. In my case, it was that simple.

public class CustomControllerSelector : DefaultHttpControllerSelector
{
    private HttpConfiguration _config;

    public IHttpControllerSelector PreviousSelector { get; set; }

    public CustomControllerSelector(HttpConfiguration configuration):base(configuration)
    {
        _config = configuration;
    }

    public override HttpControllerDescriptor SelectController(HttpRequestMessage request)
    {
        var uriSegments = request.RequestUri.Segments;
        var system = uriSegments[2];

        request.RequestUri = new System.Uri(request.RequestUri.AbsoluteUri.Replace(system, ""));

        var controllerDescriptor = PreviousSelector.SelectController(request);

        return controllerDescriptor;
    }
}

Than I had to replace the default one with my customization. But I saved the previous one because I used it after the url manipulation.

var previousSelector = config.Services.GetService(typeof(IHttpControllerSelector)) as IHttpControllerSelector;
config.Services.Replace(typeof(IHttpControllerSelector), new CustomControllerSelector(config) { PreviousSelector = previousSelector});

This was my reference.

ASP.NET Web API custom IHttpControllerSelector for a single route

Web Api dynamic url

1 Answers1