public void Configure(IApplicationBuilder app, IBooksRepository repository) { if (_environment.IsDevelopment()) { app.UseDeveloperExceptionPage(); } app.UseMiddleware <ErrorHandlingMiddleware>(); app.UseCors(builder => { builder.AllowAnyOrigin(); builder.AllowAnyHeader(); builder.AllowAnyMethod(); }); app.UseStaticFiles(); app.UseMvc(); app.UseSpa(spa => { spa.Options.SourcePath = "ClientApp"; if (_environment.IsDevelopment()) { spa.UseAngularCliServer(npmScript: "start"); } }); SampleDataInitializer.LoadDataFromJson(repository); }