eShopOnContainers/src/Services/Location/Locations.API/Startup.cs

using Autofac;
using Autofac.Extensions.DependencyInjection;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Azure.ServiceBus;
using Microsoft.eShopOnContainers.BuildingBlocks.EventBus;
using Microsoft.eShopOnContainers.BuildingBlocks.EventBus.Abstractions;
using Microsoft.eShopOnContainers.BuildingBlocks.EventBusRabbitMQ;
using Microsoft.eShopOnContainers.BuildingBlocks.EventBusServiceBus;
using Microsoft.eShopOnContainers.Services.Locations.API.Infrastructure;
using Microsoft.eShopOnContainers.Services.Locations.API.Infrastructure.Filters;
using Microsoft.eShopOnContainers.Services.Locations.API.Infrastructure.Repositories;
using Microsoft.eShopOnContainers.Services.Locations.API.Infrastructure.Services;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.HealthChecks;
using Microsoft.Extensions.Logging;
using RabbitMQ.Client;
using Swashbuckle.AspNetCore.Swagger;
using System;
using System.Collections.Generic;
using System.Threading.Tasks;

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

        public IConfiguration Configuration { get; }

        public IServiceProvider ConfigureServices(IServiceCollection services)
        {
            services.AddMvc(options =>
            {
                options.Filters.Add(typeof(HttpGlobalExceptionFilter));
            }).AddControllersAsServices();

            services.AddAuthentication()
                .AddJwtBearer(options =>
                {
                    options.Authority = Configuration.GetValue<string>("IdentityUrl");
                    options.Audience = "locations";
                    options.RequireHttpsMetadata = false;
                });

            services.Configure<LocationSettings>(Configuration);

            if (Configuration.GetValue<bool>("AzureServiceBusEnabled"))
            {
                services.AddSingleton<IServiceBusPersisterConnection>(sp =>
                {
                    var logger = sp.GetRequiredService<ILogger<DefaultServiceBusPersisterConnection>>();

                    var serviceBusConnectionString = Configuration["EventBusConnection"];
                    var serviceBusConnection = new ServiceBusConnectionStringBuilder(serviceBusConnectionString);

                    return new DefaultServiceBusPersisterConnection(serviceBusConnection, logger);
                });
            }
            else
            {
                services.AddSingleton<IRabbitMQPersistentConnection>(sp =>
                {
                    var logger = sp.GetRequiredService<ILogger<DefaultRabbitMQPersistentConnection>>();
          
                    var factory = new ConnectionFactory
                    {
                        HostName = Configuration["EventBusConnection"]
                    };

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

            services.AddHealthChecks(checks =>
            {
                checks.AddValueTaskCheck("HTTP Endpoint", () => new ValueTask<IHealthCheckResult>(HealthCheckResult.Healthy("Ok")));
            });

            RegisterEventBus(services);

            // Add framework services.
            services.AddSwaggerGen(options =>
            {
                options.DescribeAllEnumsAsStrings();
                options.SwaggerDoc("v1", new Swashbuckle.AspNetCore.Swagger.Info
                {
                    Title = "eShopOnContainers - Location HTTP API",
                    Version = "v1",
                    Description = "The Location Microservice HTTP API. This is a Data-Driven/CRUD microservice sample",
                    TermsOfService = "Terms Of Service"
                });

                options.AddSecurityDefinition("oauth2", new OAuth2Scheme
                {
                    Type = "oauth2",
                    Flow = "implicit",
                    AuthorizationUrl = $"{Configuration.GetValue<string>("IdentityUrlExternal")}/connect/authorize",
                    TokenUrl = $"{Configuration.GetValue<string>("IdentityUrlExternal")}/connect/token",
                    Scopes = new Dictionary<string, string>()
                    {
                        { "locations", "Locations API" }
                    }
                });

                options.OperationFilter<AuthorizeCheckOperationFilter>();

            });

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

            services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
            services.AddTransient<IIdentityService, IdentityService>();
            services.AddTransient<ILocationsService, LocationsService>();
            services.AddTransient<ILocationsRepository, LocationsRepository>();

            //configure autofac
            var container = new ContainerBuilder();
            container.Populate(services);

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

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
        {
            app.UseCors("CorsPolicy");

            ConfigureAuth(app);

            app.UseMvcWithDefaultRoute();

            app.UseSwagger()
              .UseSwaggerUI(c =>
              {
                  c.SwaggerEndpoint("/swagger/v1/swagger.json", "My API V1");
                  c.ConfigureOAuth2("locationsswaggerui", "", "", "Locations Swagger UI");
              });

            LocationsContextSeed.SeedAsync(app, loggerFactory)
                .Wait();
        }

        private void RegisterEventBus(IServiceCollection services)
        {
            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>();
                    var subscriptionClientName = Configuration["SubscriptionClientName"];

                    return new EventBusServiceBus(serviceBusPersisterConnection, logger,
                        eventBusSubcriptionsManager, subscriptionClientName, iLifetimeScope);
                });
            }
            else
            {
                services.AddSingleton<IEventBus, EventBusRabbitMQ>();
            }

            services.AddSingleton<IEventBusSubscriptionsManager, InMemoryEventBusSubscriptionsManager>();
        }

        protected virtual void ConfigureAuth(IApplicationBuilder app)
        {
            app.UseAuthentication();
        }
    }
}