Handling Server side routing errors with built in client side routing

Question

Hello, I have a question regarding the cleanest/easiest way to fix a routing issue. To start off, I'm using the .NET 5 framework, and have the following setup in my Startup.cs:

public void ConfigureServices(IServiceCollection services) {
    ...
    services.AddSpaStaticFiles(configuration => { configuration.RootPath = "UI"; });
  .....
}



public void Configure(IApplicationBuilder app, IWebHostEnvironment env) {
            ....
            app.UseRouting();
            app.UseSpaStaticFiles();
            app.UseAuthorization();

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

            app.UseSpa(spa =>
            {
                if (!env.IsDevelopment()) return;
                spa.Options.SourcePath = "UI/";
                spa.UseVueCli();
            });


}

Now, my problem seems to be an issue with the server side routing behavior, however I will let you diagnose. Basically, I am returning a Redirect method that redirects to a CLIENT SIDE route, (the route does NOT exist on the server side), and so when my client receives the response, it always receives the response as a 404 error message. However, if I click the request in the network tab in my browser debugger, it ends up redirecting to the client endpoint properly. I was wondering how I could resolve this 404 error and smoothly redirect to that client endpoint.

Thanks!