Configure IdentityServer4 with OWIN self-hosted WebApi

Question

I am trying to create an Identity Service using IdentityServer4. The service is self-hosted with OWIN (.Net Fx 4.7.x). Here are what I have tried so far.

Attempt#1: Use the examples from the documentation: However, all the examples are based on .Net core. Replicating the codes such as app.UseIdentityServer(); does not work simply because in the example, app is of type IApplicationBuilder, whereas in OWIN self-hosted app, we have IAppBuilder.

// Startup.cs
public void Configuration(IAppBuilder app)
{
    // Configure Web API for self-host. 
    HttpConfiguration config = new HttpConfiguration();
    config.Routes.MapHttpRoute(
        name: "DefaultApi",
        routeTemplate: "api/{controller}/{id}",
        defaults: new { id = RouteParameter.Optional }
    );

    // Configure Unity IOC

    app.UseIdentityServer(); //<--doesn't compile
    app.UseWebApi(config);
}

Attempt#2: Register the IdentityServer middleware manually: I tried to register the needed middlewares manually, by looking at the sources. This looks something like below:

//Startup.cs
public void Configuration(IAppBuilder app)
{
    ...
    // Configure Unity IOC

    app.Use<IdentityServerMiddleware>(
        config.DependencyResolver.GetService(typeof(ILogger<IdentityServerMiddleware>)));
    app.UseWebApi(config);
}

This too does not work, as the Main method throws the following error while staring the WebApp with WebApp.Start<Startup>(baseAddress);

No conversion available between System.Web.Http.Owin.HttpMessageHandlerAdapter and Microsoft.AspNetCore.Http.RequestDelegate. Parameter name: signature

How can I correctly configure this? I know that I can possibly use IdentityServer3 in this case, but I am keen on using IdentityServer4 as IdentityServer3 is not maintained anymore.

You can't, identity server 4 is for dotnet core only. You can create a separate project as dotnet core using net framework or not your choice, then that would be your end point for all your applications for authentication. Otherwise you have to use identity server 3. — penleychan, May 14 '18 at 11:56
Your question is a little unclear. Are you trying to create an Identity server using Identity server 4 for with .net 4.7? Or are you trying to connect to an Identity server using .net 4.7? — Linda Lawton - DaImTo, May 14 '18 at 12:02
@DaImTo Sorry for the confusion. Updated the question. I am trying to create an identity service. — Sayan Pal, May 14 '18 at 12:07

score 2 · Accepted Answer · edited May 15 '18 at 10:15

Directly from the documentation for Identity server 4

IdentityServer4 is an OpenID Connect and OAuth 2.0 framework for ASP.NET Core 2.

Identity server 4 only works with Asp.Net core 2.0. You are not going to be able to use this to create an identity server with old ASP.Net (Owin/KATANA) I recommend you switch to ASP.NET Core 2.0.

As mentioned in comments you could go back to Identity Server 3 but this is no longer supported so there will probably not be any security updates if any issues arise with it. Due to that i would not personally use it in a new production product.

Configure IdentityServer4 with OWIN self-hosted WebApi

1 Answers1