Telling ASP.NET Core to map the controllers to actual endpoints

TIL that to add controllers to an ASP.NET Core application, it’s not as straight forward as simply creating a controller which inherits from Controller or even adding the Route attribute to it. It’s also necessary to explicitely tell the framework to map the controllers to endpoints!

In the Startup.cs class, you’ll need to add the following:

public void ConfigureServices(IServiceCollection services)
{
    // ...

    services.AddControllers();
}

As well as:

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
    // ...

    app.UseRouting();
    app.UseEndpoints(endpoints =>
    {
        endpoints.MapControllers();
    });
}

Of course, don’t forget to mark the Controller:

[Route("tsunami")]
public class TsunamiController : Controller
{
    // ...
}