eShopOnContainers/src/Web/WebSPA/Startup.cs

namespace eShopConContainers.WebSPA;

public class Startup
{
    public Startup(IConfiguration configuration)
    {
        Configuration = configuration;
    }

    public IConfiguration Configuration { get; }

    public Startup()
    {
        var localPath = new Uri(Configuration["ASPNETCORE_URLS"])?.LocalPath ?? "/";
        Configuration["BaseUrl"] = localPath;
    }

    // This method gets called by the runtime. Use this method to add services to the container.
    // For more information on how to configure your application, visit http://go.microsoft.com/fwlink/?LinkID=398940
    public void ConfigureServices(IServiceCollection services)
    {
        RegisterAppInsights(services);

        services.AddHealthChecks()
            .AddCheck("self", () => HealthCheckResult.Healthy())
            .AddUrlGroup(new Uri(Configuration["IdentityUrlHC"]), name: "identityapi-check", tags: new string[] { "identityapi" });

        services.Configure<AppSettings>(Configuration);

        if (Configuration.GetValue<string>("IsClusterEnv") == bool.TrueString)
        {
            services.AddDataProtection(opts =>
            {
                opts.ApplicationDiscriminator = "eshop.webspa";
            })
            .PersistKeysToStackExchangeRedis(ConnectionMultiplexer.Connect(Configuration["DPConnectionString"]), "DataProtection-Keys");
        }

        // Add Antiforgery services and configure the header name that angular will use by default.
        services.AddAntiforgery(options => options.HeaderName = "X-XSRF-TOKEN");

        // Add controllers support and add a global AutoValidateAntiforgeryTokenFilter that will make the application check for an Antiforgery token on all "mutating" requests (POST, PUT, DELETE).
        // The AutoValidateAntiforgeryTokenFilter is an internal class registered when we register views, so we need to register controllers and views also.
        services.AddControllersWithViews(options => options.Filters.Add(new AutoValidateAntiforgeryTokenAttribute()))
            .AddJsonOptions(options =>
            {
                options.JsonSerializerOptions.PropertyNameCaseInsensitive = true;
            });

        // Setup where the compiled version of our spa application will be, when in production. 
        services.AddSpaStaticFiles(configuration =>
        {
            configuration.RootPath = "wwwroot";
        });
    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILoggerFactory loggerFactory, IAntiforgery antiforgery)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }

        // Here we add Angular default Antiforgery cookie name on first load. https://angular.io/guide/http#security-xsrf-protection
        // This cookie will be read by Angular app and its value will be sent back to the application as the header configured in .AddAntiforgery()
        app.Use(next => context =>
        {
            string path = context.Request.Path.Value;

            if (
                string.Equals(path, "/", StringComparison.OrdinalIgnoreCase) ||
                string.Equals(path, "/index.html", StringComparison.OrdinalIgnoreCase))
            {
                // The request token has to be sent as a JavaScript-readable cookie, 
                // and Angular uses it by default.
                var tokens = antiforgery.GetAndStoreTokens(context);
                context.Response.Cookies.Append("XSRF-TOKEN", tokens.RequestToken,
                    new CookieOptions() { HttpOnly = false });
            }

            return next(context);
        });

        //Seed Data
        WebContextSeed.Seed(app, env, loggerFactory);

        var pathBase = Configuration["PATH_BASE"];

        if (!string.IsNullOrEmpty(pathBase))
        {
            loggerFactory.CreateLogger<Startup>().LogDebug("Using PATH BASE '{pathBase}'", pathBase);
            app.UsePathBase(pathBase);
        }

        app.UseDefaultFiles();
        app.UseStaticFiles();

        // this will make the application to respond with the index.html and the rest of the assets present on the configured folder (at AddSpaStaticFiles() (wwwroot))
        if (!env.IsDevelopment())
        {
            app.UseSpaStaticFiles();
        }
        app.UseRouting();
        app.UseEndpoints(endpoints =>
        {
            endpoints.MapDefaultControllerRoute();
            endpoints.MapControllers();
            endpoints.MapHealthChecks("/liveness", new HealthCheckOptions
            {
                Predicate = r => r.Name.Contains("self")
            });
            endpoints.MapHealthChecks("/hc", new HealthCheckOptions()
            {
                Predicate = _ => true,
                ResponseWriter = UIResponseWriter.WriteHealthCheckUIResponse
            });
        });

        // Handles all still unnatended (by any other middleware) requests by returning the default page of the SPA (wwwroot/index.html).
        app.UseSpa(spa =>
        {
            // To learn more about options for serving an Angular SPA from ASP.NET Core,
            // see https://go.microsoft.com/fwlink/?linkid=864501

            // the root of the angular app. (Where the package.json lives)
            spa.Options.SourcePath = "Client";

            if (env.IsDevelopment())
            { 

                // use the SpaServices extension method for angular, that will make the application to run "ng serve" for us, when in development.
                spa.UseAngularCliServer(npmScript: "start");
            }
        });
    }

    private void RegisterAppInsights(IServiceCollection services)
    {
        services.AddApplicationInsightsTelemetry(Configuration);
        services.AddApplicationInsightsKubernetesEnricher();
    }
}