eShopOnContainers/src/Services/Catalog/Catalog.API/Startup.cs

using Autofac;
using Autofac.Extensions.DependencyInjection;
using Catalog.API.Grpc;
using global::Catalog.API.Infrastructure.Filters;
using global::Catalog.API.IntegrationEvents;
using HealthChecks.UI.Client;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Diagnostics.HealthChecks;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Azure.ServiceBus;
using Microsoft.EntityFrameworkCore;
using Microsoft.eShopOnContainers.BuildingBlocks.EventBus;
using Microsoft.eShopOnContainers.BuildingBlocks.EventBus.Abstractions;
using Microsoft.eShopOnContainers.BuildingBlocks.EventBusRabbitMQ;
using Microsoft.eShopOnContainers.BuildingBlocks.EventBusServiceBus;
using Microsoft.eShopOnContainers.BuildingBlocks.IntegrationEventLogEF;
using Microsoft.eShopOnContainers.BuildingBlocks.IntegrationEventLogEF.Services;
using Microsoft.eShopOnContainers.Services.Catalog.API.Infrastructure;
using Microsoft.eShopOnContainers.Services.Catalog.API.IntegrationEvents.EventHandling;
using Microsoft.eShopOnContainers.Services.Catalog.API.IntegrationEvents.Events;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Diagnostics.HealthChecks;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using Microsoft.OpenApi.Models;
using OpenTelemetry.Customization;
using OpenTelemetry.Customization.Extensions;
using RabbitMQ.Client;
using System;
using System.Data.Common;
using System.IO;
using System.Reflection;

namespace Microsoft.eShopOnContainers.Services.Catalog.API
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        public IServiceProvider ConfigureServices(IServiceCollection services)
        {
            services.AddAppInsight(Configuration)
                .AddGrpc().Services
                .AddCustomMVC(Configuration)
                .AddCustomDbContext(Configuration)
                .AddCustomOptions(Configuration)
                .AddIntegrationServices(Configuration)
                .AddEventBus(Configuration)
                .AddSwagger(Configuration)
                .AddCustomHealthCheck(Configuration)
                .AddOpenTelemetry(new OpenTelemetryConfig() {  ServiceName= "Catalog.API", 
                    ExportType= Configuration.GetValue<string>("OTEL_USE_EXPORTER"), 
                    ExportToolEndpoint = Configuration.GetValue<string>("OTEL_EXPORTER_TOOL_ENDPOINT")
                });

            var container = new ContainerBuilder();
            container.Populate(services);

            return new AutofacServiceProvider(container.Build());
        }

        public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILoggerFactory loggerFactory)
        {
            //Configure logs

            //loggerFactory.AddAzureWebAppDiagnostics();
            //loggerFactory.AddApplicationInsights(app.ApplicationServices, LogLevel.Trace);

            var pathBase = Configuration["PATH_BASE"];

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

            app.UseSwagger()
             .UseSwaggerUI(c =>
             {
                 c.SwaggerEndpoint($"{ (!string.IsNullOrEmpty(pathBase) ? pathBase : string.Empty) }/swagger/v1/swagger.json", "Catalog.API V1");
             });

            app.UseRouting();
            app.UseCors("CorsPolicy");
            app.UseEndpoints(endpoints =>
            {
                endpoints.MapDefaultControllerRoute();
                endpoints.MapControllers();
                endpoints.MapGet("/_proto/", async ctx =>
                {
                    ctx.Response.ContentType = "text/plain";
                    using var fs = new FileStream(Path.Combine(env.ContentRootPath, "Proto", "catalog.proto"), FileMode.Open, FileAccess.Read);
                    using var sr = new StreamReader(fs);
                    while (!sr.EndOfStream)
                    {
                        var line = await sr.ReadLineAsync();
                        if (line != "/* >>" || line != "<< */")
                        {
                            await ctx.Response.WriteAsync(line);
                        }
                    }
                });
                endpoints.MapGrpcService<CatalogService>();
                endpoints.MapHealthChecks("/hc", new HealthCheckOptions()
                {
                    Predicate = _ => true,
                    ResponseWriter = UIResponseWriter.WriteHealthCheckUIResponse
                });
                endpoints.MapHealthChecks("/liveness", new HealthCheckOptions
                {
                    Predicate = r => r.Name.Contains("self")
                });
            });

            ConfigureEventBus(app);
        }

        protected virtual void ConfigureEventBus(IApplicationBuilder app)
        {
            var eventBus = app.ApplicationServices.GetRequiredService<IEventBus>();
            eventBus.Subscribe<OrderStatusChangedToAwaitingValidationIntegrationEvent, OrderStatusChangedToAwaitingValidationIntegrationEventHandler>();
            eventBus.Subscribe<OrderStatusChangedToPaidIntegrationEvent, OrderStatusChangedToPaidIntegrationEventHandler>();
        }
    }

    public static class CustomExtensionMethods
    {
        public static IServiceCollection AddAppInsight(this IServiceCollection services, IConfiguration configuration)
        {
            services.AddApplicationInsightsTelemetry(configuration);
            services.AddApplicationInsightsKubernetesEnricher();

            return services;
        }

        public static IServiceCollection AddCustomMVC(this IServiceCollection services, IConfiguration configuration)
        {
            services.AddControllers(options =>
            {
                options.Filters.Add(typeof(HttpGlobalExceptionFilter));
            })
            .AddJsonOptions(options => options.JsonSerializerOptions.WriteIndented = true);

            services.AddCors(options =>
            {
                options.AddPolicy("CorsPolicy",
                    builder => builder
                    .SetIsOriginAllowed((host) => true)
                    .AllowAnyMethod()
                    .AllowAnyHeader()
                    .AllowCredentials());
            });

            return services;
        }

        public static IServiceCollection AddCustomHealthCheck(this IServiceCollection services, IConfiguration configuration)
        {
            var accountName = configuration.GetValue<string>("AzureStorageAccountName");
            var accountKey = configuration.GetValue<string>("AzureStorageAccountKey");

            var hcBuilder = services.AddHealthChecks();

            hcBuilder
                .AddCheck("self", () => HealthCheckResult.Healthy())
                .AddSqlServer(
                    configuration["ConnectionString"],
                    name: "CatalogDB-check",
                    tags: new string[] { "catalogdb" });

            if (!string.IsNullOrEmpty(accountName) && !string.IsNullOrEmpty(accountKey))
            {
                hcBuilder
                    .AddAzureBlobStorage(
                        $"DefaultEndpointsProtocol=https;AccountName={accountName};AccountKey={accountKey};EndpointSuffix=core.windows.net",
                        name: "catalog-storage-check",
                        tags: new string[] { "catalogstorage" });
            }

            if (configuration.GetValue<bool>("AzureServiceBusEnabled"))
            {
                hcBuilder
                    .AddAzureServiceBusTopic(
                        configuration["EventBusConnection"],
                        topicName: "eshop_event_bus",
                        name: "catalog-servicebus-check",
                        tags: new string[] { "servicebus" });
            }
            else
            {
                hcBuilder
                    .AddRabbitMQ(
                        $"amqp://{configuration["EventBusConnection"]}",
                        name: "catalog-rabbitmqbus-check",
                        tags: new string[] { "rabbitmqbus" });
            }

            return services;
        }

        public static IServiceCollection AddCustomDbContext(this IServiceCollection services, IConfiguration configuration)
        {
            services.AddEntityFrameworkSqlServer()
                .AddDbContext<CatalogContext>(options =>
            {
                options.UseSqlServer(configuration["ConnectionString"],
                                     sqlServerOptionsAction: sqlOptions =>
                                     {
                                         sqlOptions.MigrationsAssembly(typeof(Startup).GetTypeInfo().Assembly.GetName().Name);
                                         //Configuring Connection Resiliency: https://docs.microsoft.com/en-us/ef/core/miscellaneous/connection-resiliency 
                                         sqlOptions.EnableRetryOnFailure(maxRetryCount: 15, maxRetryDelay: TimeSpan.FromSeconds(30), errorNumbersToAdd: null);
                                     });
            });

            services.AddDbContext<IntegrationEventLogContext>(options =>
            {
                options.UseSqlServer(configuration["ConnectionString"],
                                     sqlServerOptionsAction: sqlOptions =>
                                     {
                                         sqlOptions.MigrationsAssembly(typeof(Startup).GetTypeInfo().Assembly.GetName().Name);
                                         //Configuring Connection Resiliency: https://docs.microsoft.com/en-us/ef/core/miscellaneous/connection-resiliency 
                                         sqlOptions.EnableRetryOnFailure(maxRetryCount: 15, maxRetryDelay: TimeSpan.FromSeconds(30), errorNumbersToAdd: null);
                                     });
            });

            return services;
        }

        public static IServiceCollection AddCustomOptions(this IServiceCollection services, IConfiguration configuration)
        {
            services.Configure<CatalogSettings>(configuration);
            services.Configure<ApiBehaviorOptions>(options =>
            {
                options.InvalidModelStateResponseFactory = context =>
                {
                    var problemDetails = new ValidationProblemDetails(context.ModelState)
                    {
                        Instance = context.HttpContext.Request.Path,
                        Status = StatusCodes.Status400BadRequest,
                        Detail = "Please refer to the errors property for additional details."
                    };

                    return new BadRequestObjectResult(problemDetails)
                    {
                        ContentTypes = { "application/problem+json", "application/problem+xml" }
                    };
                };
            });

            return services;
        }

        public static IServiceCollection AddSwagger(this IServiceCollection services, IConfiguration configuration)
        {
            services.AddSwaggerGen(options =>
            {
                options.DescribeAllEnumsAsStrings();
                options.SwaggerDoc("v1", new OpenApiInfo
                {
                    Title = "eShopOnContainers - Catalog HTTP API",
                    Version = "v1",
                    Description = "The Catalog Microservice HTTP API. This is a Data-Driven/CRUD microservice sample"
                });
            });

            return services;

        }

        public static IServiceCollection AddIntegrationServices(this IServiceCollection services, IConfiguration configuration)
        {
            services.AddTransient<Func<DbConnection, IIntegrationEventLogService>>(
                sp => (DbConnection c) => new IntegrationEventLogService(c));

            services.AddTransient<ICatalogIntegrationEventService, CatalogIntegrationEventService>();

            if (configuration.GetValue<bool>("AzureServiceBusEnabled"))
            {
                services.AddSingleton<IServiceBusPersisterConnection>(sp =>
                {
                    var settings = sp.GetRequiredService<IOptions<CatalogSettings>>().Value;
                    var serviceBusConnection = new ServiceBusConnectionStringBuilder(settings.EventBusConnection);
                    var subscriptionClientName = configuration["SubscriptionClientName"];

                    return new DefaultServiceBusPersisterConnection(serviceBusConnection, subscriptionClientName);
                });
            }
            else
            {
                services.AddSingleton<IRabbitMQPersistentConnection>(sp =>
                {
                    var settings = sp.GetRequiredService<IOptions<CatalogSettings>>().Value;
                    var logger = sp.GetRequiredService<ILogger<DefaultRabbitMQPersistentConnection>>();

                    var factory = new ConnectionFactory()
                    {
                        HostName = configuration["EventBusConnection"],
                        DispatchConsumersAsync = true
                    };

                    if (!string.IsNullOrEmpty(configuration["EventBusUserName"]))
                    {
                        factory.UserName = configuration["EventBusUserName"];
                    }

                    if (!string.IsNullOrEmpty(configuration["EventBusPassword"]))
                    {
                        factory.Password = configuration["EventBusPassword"];
                    }

                    var retryCount = 5;
                    if (!string.IsNullOrEmpty(configuration["EventBusRetryCount"]))
                    {
                        retryCount = int.Parse(configuration["EventBusRetryCount"]);
                    }

                    return new DefaultRabbitMQPersistentConnection(factory, logger, retryCount);
                });
            }

            return services;
        }

        public static IServiceCollection AddEventBus(this IServiceCollection services, IConfiguration configuration)
        {
            if (configuration.GetValue<bool>("AzureServiceBusEnabled"))
            {
                services.AddSingleton<IEventBus, EventBusServiceBus>(sp =>
                {
                    var serviceBusPersisterConnection = sp.GetRequiredService<IServiceBusPersisterConnection>();
                    var iLifetimeScope = sp.GetRequiredService<ILifetimeScope>();
                    var logger = sp.GetRequiredService<ILogger<EventBusServiceBus>>();
                    var eventBusSubcriptionsManager = sp.GetRequiredService<IEventBusSubscriptionsManager>();

                    return new EventBusServiceBus(serviceBusPersisterConnection, logger,
                        eventBusSubcriptionsManager, iLifetimeScope);
                });

            }
            else
            {
                services.AddSingleton<IEventBus, EventBusRabbitMQ>(sp =>
                {
                    var subscriptionClientName = configuration["SubscriptionClientName"];
                    var rabbitMQPersistentConnection = sp.GetRequiredService<IRabbitMQPersistentConnection>();
                    var iLifetimeScope = sp.GetRequiredService<ILifetimeScope>();
                    var logger = sp.GetRequiredService<ILogger<EventBusRabbitMQ>>();
                    var eventBusSubcriptionsManager = sp.GetRequiredService<IEventBusSubscriptionsManager>();

                    var retryCount = 5;
                    if (!string.IsNullOrEmpty(configuration["EventBusRetryCount"]))
                    {
                        retryCount = int.Parse(configuration["EventBusRetryCount"]);
                    }

                    return new EventBusRabbitMQ(rabbitMQPersistentConnection, logger, iLifetimeScope, eventBusSubcriptionsManager, subscriptionClientName, retryCount);
                });
            }

            services.AddSingleton<IEventBusSubscriptionsManager, InMemoryEventBusSubscriptionsManager>();
            services.AddTransient<OrderStatusChangedToAwaitingValidationIntegrationEventHandler>();
            services.AddTransient<OrderStatusChangedToPaidIntegrationEventHandler>();

            return services;
        }
    }
}