Startup.cs

using System;
using DevExpress.AspNetCore;
using DevExpress.AspNetCore.Reporting;
using DevExpress.XtraReports.Services;
using DevExpress.XtraReports.Web.Extensions;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using ReportingAppAsyncServices.Services;

namespace ReportingAppAsyncServices
{
    public class Startup {
        public Startup(IConfiguration configuration, IWebHostEnvironment hostingEnvironment) {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services) {
            services.AddDevExpressControls();
            services.AddSession();
            services.AddScoped<ReportStorageWebExtension, CustomReportStorageWebExtension>();
            services.AddScoped<IReportProviderAsync, CustomReportProviderAsync>();

            services
                .AddControllersWithViews()
                .AddNewtonsoftJson();
            services.ConfigureReportingServices(configurator => {
                configurator.ConfigureReportDesigner(designerConfigurator => {
                    designerConfigurator.RegisterDataSourceWizardConfigFileConnectionStringsProvider();
                });
                configurator.ConfigureWebDocumentViewer(viewerConfigurator => {
                    viewerConfigurator.UseCachedReportSourceBuilder();
                });
                configurator.UseAsyncEngine();
            });
        }

        // 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) {
            var reportingLogger = loggerFactory.CreateLogger("DXReporting");
            DevExpress.XtraReports.Web.ClientControls.LoggerService.Initialize((exception, message) => {
                var logMessage = $"[{DateTime.Now}]: Exception occurred. Message: '{message}'. Exception Details:\r\n{exception}";
                reportingLogger.LogError(logMessage);
            });
            DevExpress.XtraReports.Configuration.Settings.Default.UserDesignerOptions.DataBindingMode = DevExpress.XtraReports.UI.DataBindingMode.Expressions;
            app.UseSession();
            app.UseDevExpressControls();
            System.Net.ServicePointManager.SecurityProtocol |= System.Net.SecurityProtocolType.Tls12;
            if(env.IsDevelopment()) {
                app.UseDeveloperExceptionPage();
            } else {
                app.UseExceptionHandler("/Home/Error");
                // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
                app.UseHsts();
            }
            app.UseHttpsRedirection();
            app.UseStaticFiles();
            
            app.UseRouting();

            app.UseAuthorization();
            app.UseEndpoints(endpoints => {
                endpoints.MapControllerRoute(
                    name: "default",
                    pattern: "{controller=Home}/{action=Index}/{id?}");
            });
        }
    }
}