Q:

What is equivalent to `MapSpaFallbackRoute` for ASP.NET Core 3.0 endpoints?

In ASP.NET Core 2.x I used standard routes registation Configure method of Startup class to register fallback route for SPA application using MapSpaFallbackRoute extension method from Microsoft.AspNetCore.SpaServices.Extensions Nuget package:
public void Configure(IApplicationBuilder app)
{
    // ...
    app.UseMvc(routes =>
    {
        routes.MapRoute(
            name: "default",
            template: "{controller=Home}/{action=Index}/{id?}");
        routes.MapSpaFallbackRoute(
            name: "spa-fallback",
            defaults: new { controller = "Home", action = "Index" });
    });
}

I cannot find similar extension method when using ASP.NET Core 3.0 recommended UseEndpoints extension method for endpoints registration.

A:

In ASP.NET Core 3.0 extension method MapFallbackToController has same functionality to MapSpaFallbackRoute extension method.
public void Configure(IApplicationBuilder app)
{
    app.UseRouting();
    app.UseEndpoints(endpoints =>
    {
        endpoints.MapControllerRoute(
            name: "default",
            pattern: "{controller=Home}/{action=Index}/{id?}");

        endpoints.MapFallbackToController("Index", "Home");
    });
}

