Window authentication with Identity Server 4 - Part 1 (hybrid client)

Before reading this post, you must be aware of basics of identity server and oauth terms. We will not delve into the basics of identity server here.

Setting up identity server 4

Setup a .Net Core 3.x project and add the nuget package reference for Identity server 4.

Important point here is to have a project with a flexibility to add new views/pages.

Once we add the nuget reference of Identity server 4, we will add a few lines of code in ConfigureServices method of our Startup.cs file

Here is a look at our Config.cs class

This way we have added a client with a custom grant type "iwa" representing integrated window authentication. This will be used in part 2 when we will protect our API resources for a SPA.

Window authentication with hybrid flow i.e. MVC client

Next we will create a MVC project (you can create any web project). We need to ensure that the client parameters used in this project should be same as registered in Identity Server setup.
Here is the view of our startup.cs file

Now we need to add a view our identity server project where this MVC application will redirect and authenticate itself and returns back. This redirection will be very spontaneous.
Let's add an account controller in our identity server project and add below methods
Now we are ready to rock, once you run the identity server and mvc application then you will see that mvc application will redirect automatically to identity server, identity server will authenticate the window user and we are then again redirected back to mvc application url. This whole process is automated and quick to execute.