Refactor aggregators to use AddHttpClient like on WebMVC

src/ApiGateways/Mobile.Bff.Shopping/aggregator/Infrastructure/HttpClientAuthorizationDelegatingHandler.cs

@@ -0,0 +1,49 @@
+using Microsoft.AspNetCore.Authentication;
+using Microsoft.AspNetCore.Http;
+using System.Collections.Generic;
+using System.Net.Http;
+using System.Net.Http.Headers;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Infrastructure
+{
+    public class HttpClientAuthorizationDelegatingHandler
+        : DelegatingHandler
+    {
+        private readonly IHttpContextAccessor _httpContextAccesor;
+
+        public HttpClientAuthorizationDelegatingHandler(IHttpContextAccessor httpContextAccesor)
+        {
+            _httpContextAccesor = httpContextAccesor;
+        }
+
+        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+        {
+            var authorizationHeader = _httpContextAccesor.HttpContext
+                .Request.Headers["Authorization"];
+
+            if (!string.IsNullOrEmpty(authorizationHeader))
+            {
+                request.Headers.Add("Authorization", new List<string>() { authorizationHeader });
+            }
+
+            var token = await GetToken();
+
+            if (token != null)
+            {
+                request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
+            }
+
+            return await base.SendAsync(request, cancellationToken);
+        }
+
+        async Task<string> GetToken()
+        {
+            const string ACCESS_TOKEN = "access_token";
+
+            return await _httpContextAccesor.HttpContext
+                .GetTokenAsync(ACCESS_TOKEN);
+        }
+    }
+}

src/ApiGateways/Mobile.Bff.Shopping/aggregator/Mobile.Shopping.HttpAggregator.csproj

@@ -14,6 +14,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.App" />
     <PackageReference Include="Swashbuckle.AspNetCore" Version="1.1.0" />
+    <PackageReference Include="Microsoft.Extensions.Http.Polly" Version="2.1.0-rc1-final" />
   </ItemGroup>
 
   <ItemGroup>

src/ApiGateways/Mobile.Bff.Shopping/aggregator/Services/BasketService.cs

@@ -1,53 +1,41 @@
-using System;
+using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Config;
-using System.Collections.Generic;
+using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Models;
-using System.Linq;
-using System.Threading.Tasks;
-using Microsoft.AspNetCore.Authentication;
-using Microsoft.AspNetCore.Http;
-using Microsoft.eShopOnContainers.BuildingBlocks.Resilience.Http;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using Newtonsoft.Json;
-using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Config;
+using System.Net.Http;
-using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Models;
+using System.Threading.Tasks;
 
 namespace Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Services
 {
     public class BasketService : IBasketService
     {
 
-        private readonly IHttpClient _apiClient;
+        private readonly HttpClient _httpClient;
         private readonly ILogger<BasketService> _logger;
         private readonly UrlsConfig _urls;
-        private readonly IHttpContextAccessor _httpContextAccessor;
 
-        public BasketService(IHttpClient httpClient, IHttpContextAccessor httpContextAccessor, ILogger<BasketService> logger, IOptionsSnapshot<UrlsConfig> config)
+        public BasketService(HttpClient httpClient, ILogger<BasketService> logger, IOptions<UrlsConfig> config)
         {
-            _apiClient = httpClient;
+            _httpClient = httpClient;
             _logger = logger;
             _urls = config.Value;
-            _httpContextAccessor = httpContextAccessor;
         }
 
         public async Task<BasketData> GetById(string id)
         {
-            var token = await GetUserTokenAsync();
+            var data = await _httpClient.GetStringAsync(_urls.Basket + UrlsConfig.BasketOperations.GetItemById(id));
-            var data = await _apiClient.GetStringAsync(_urls.Basket +  UrlsConfig.BasketOperations.GetItemById(id), token);
+
             var basket = !string.IsNullOrEmpty(data) ? JsonConvert.DeserializeObject<BasketData>(data) : null;
+
             return basket;
         }
 
         public async Task Update(BasketData currentBasket)
         {
-            var token = await GetUserTokenAsync();
+            var basketContent = new StringContent(JsonConvert.SerializeObject(currentBasket), System.Text.Encoding.UTF8, "application/json");
-            var data = await _apiClient.PostAsync<BasketData>(_urls.Basket + UrlsConfig.BasketOperations.UpdateBasket(), currentBasket, token);
-            int i = 0;
-        }
 
-        async Task<string> GetUserTokenAsync()
+            var data = await _httpClient.PostAsync(_urls.Basket + UrlsConfig.BasketOperations.UpdateBasket(), basketContent);
-        {
-            var context = _httpContextAccessor.HttpContext;
-            return await context.GetTokenAsync("access_token");
         }
     }
 }

src/ApiGateways/Mobile.Bff.Shopping/aggregator/Services/CatalogService.cs

@@ -1,43 +1,41 @@
-using System;
+using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Config;
-using System.Collections.Generic;
+using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Models;
-using System.Linq;
-using System.Threading.Tasks;
-using Microsoft.eShopOnContainers.BuildingBlocks.Resilience.Http;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using Newtonsoft.Json;
-using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Config;
+using System.Collections.Generic;
-using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Models;
+using System.Net.Http;
+using System.Threading.Tasks;
 
 namespace Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Services
 {
     public class CatalogService : ICatalogService
     {
-
+        private readonly HttpClient _httpClient;
-        private readonly IHttpClient _apiClient;
         private readonly ILogger<CatalogService> _logger;
         private readonly UrlsConfig _urls;
 
-        public CatalogService(IHttpClient httpClient, ILogger<CatalogService> logger, IOptionsSnapshot<UrlsConfig> config)
+        public CatalogService(HttpClient httpClient, ILogger<CatalogService> logger, IOptions<UrlsConfig> config)
         {
-            _apiClient = httpClient;
+            _httpClient = httpClient;
             _logger = logger;
             _urls = config.Value;
         }
 
         public async Task<CatalogItem> GetCatalogItem(int id)
         {
-            var data = await _apiClient.GetStringAsync(_urls.Catalog + UrlsConfig.CatalogOperations.GetItemById(id));
+            var stringContent = await _httpClient.GetStringAsync(_urls.Catalog + UrlsConfig.CatalogOperations.GetItemById(id));
-            var item = JsonConvert.DeserializeObject<CatalogItem>(data);
+            var catalogItem = JsonConvert.DeserializeObject<CatalogItem>(stringContent);
-            return item;
+
+            return catalogItem;
         }
 
         public async Task<IEnumerable<CatalogItem>> GetCatalogItems(IEnumerable<int> ids)
         {
-            var data = await _apiClient.GetStringAsync(_urls.Catalog + UrlsConfig.CatalogOperations.GetItemsById(ids));
+            var stringContent = await _httpClient.GetStringAsync(_urls.Catalog + UrlsConfig.CatalogOperations.GetItemsById(ids));
-            var item = JsonConvert.DeserializeObject<CatalogItem[]>(data);
+            var catalogItems = JsonConvert.DeserializeObject<CatalogItem[]>(stringContent);
-            return item;
 
+            return catalogItems;
         }
     }
 }

src/ApiGateways/Mobile.Bff.Shopping/aggregator/Services/OrderApiClient.cs

@@ -1,24 +1,20 @@
-using System;
+using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Config;
-using System.Collections.Generic;
+using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Models;
-using System.Linq;
-using System.Threading.Tasks;
-using Microsoft.eShopOnContainers.BuildingBlocks.Resilience.Http;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using Newtonsoft.Json;
-using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Config;
+using System.Net.Http;
-using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Models;
+using System.Threading.Tasks;
 
 namespace Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Services
 {
     public class OrderApiClient : IOrderApiClient
     {
-
+        private readonly HttpClient _apiClient;
-        private readonly IHttpClient _apiClient;
         private readonly ILogger<OrderApiClient> _logger;
         private readonly UrlsConfig _urls;
 
-        public OrderApiClient(IHttpClient httpClient, ILogger<OrderApiClient> logger, IOptionsSnapshot<UrlsConfig> config)
+        public OrderApiClient(HttpClient httpClient, ILogger<OrderApiClient> logger, IOptions<UrlsConfig> config)
         {
             _apiClient = httpClient;
             _logger = logger;
@@ -27,11 +23,15 @@ namespace Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Services
 
         public async Task<OrderData> GetOrderDraftFromBasket(BasketData basket)
         {
-            var url = _urls.Orders + UrlsConfig.OrdersOperations.GetOrderDraft();
+            var uri = _urls.Orders + UrlsConfig.OrdersOperations.GetOrderDraft();
-            var response = await _apiClient.PostAsync<BasketData>(url, basket);
+            var content = new StringContent(JsonConvert.SerializeObject(basket), System.Text.Encoding.UTF8, "application/json");
+            var response = await _apiClient.PostAsync(uri, content);
+
             response.EnsureSuccessStatusCode();
-            var jsonResponse = await response.Content.ReadAsStringAsync();
+
-            return JsonConvert.DeserializeObject<OrderData>(jsonResponse);
+            var ordersDraftResponse = await response.Content.ReadAsStringAsync();
+
+            return JsonConvert.DeserializeObject<OrderData>(ordersDraftResponse);
         }
     }
 }

src/ApiGateways/Mobile.Bff.Shopping/aggregator/Startup.cs

@@ -16,6 +16,9 @@ using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Config;
 using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Filters.Basket.API.Infrastructure.Filters;
 using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Services;
 using Swashbuckle.AspNetCore.Swagger;
+using Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator.Infrastructure;
+using Polly.Extensions.Http;
+using Polly;
 
 namespace Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator
 {
@@ -31,84 +34,16 @@ namespace Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator
         // This method gets called by the runtime. Use this method to add services to the container.
         public void ConfigureServices(IServiceCollection services)
         {
-            services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
+            services.AddCustomMvc(Configuration)
-            services.AddSingleton<IHttpClient, StandardHttpClient>();
+                 .AddCustomAuthentication(Configuration)
-            services.AddTransient<ICatalogService, CatalogService>();
+                 .AddHttpServices();
-            services.AddTransient<IBasketService, BasketService>();
-            services.AddTransient<IOrderApiClient, OrderApiClient>();
-
-            services.AddOptions();
-            services.Configure<UrlsConfig>(Configuration.GetSection("urls"));
-
-            services.AddMvc();
-
-            services.AddSwaggerGen(options =>
-            {
-                options.DescribeAllEnumsAsStrings();
-                options.SwaggerDoc("v1", new Swashbuckle.AspNetCore.Swagger.Info
-                {
-                    Title = "Shopping Aggregator for Mobile Clients",
-                    Version = "v1",
-                    Description = "Shopping Aggregator for Mobile Clients",
-                    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>()
-                    {
-                        { "mobileshoppingagg", "Shopping Aggregator for Mobile Clients" }
-                    }
-                });
-
-                options.OperationFilter<AuthorizeCheckOperationFilter>();
-            });
-
-            services.AddCors(options =>
-            {
-                options.AddPolicy("CorsPolicy",
-                    builder => builder.AllowAnyOrigin()
-                    .AllowAnyMethod()
-                    .AllowAnyHeader()
-                    .AllowCredentials());
-            });
-
-
-            JwtSecurityTokenHandler.DefaultInboundClaimTypeMap.Clear();
-            var identityUrl = Configuration.GetValue<string>("urls:identity");
-            services.AddAuthentication(options =>
-            {
-                options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
-                options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
-
-            }).AddJwtBearer(options =>
-            {
-                options.Authority = identityUrl;
-                options.RequireHttpsMetadata = false;
-                options.Audience = "mobileshoppingagg";
-                options.Events = new JwtBearerEvents()
-                {
-                    OnAuthenticationFailed = async ctx =>
-                    {
-                        int i = 0;
-                    },
-                    OnTokenValidated = async ctx =>
-                    {
-                        int i = 0;
-                    }
-                };
-            });
         }
 
         // 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)
         {
-
             var pathBase = Configuration["PATH_BASE"];
+
             if (!string.IsNullOrEmpty(pathBase))
             {
                 loggerFactory.CreateLogger("init").LogDebug($"Using PATH BASE '{pathBase}'");
@@ -131,8 +66,115 @@ namespace Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregator
                c.SwaggerEndpoint($"{ (!string.IsNullOrEmpty(pathBase) ? pathBase : string.Empty) }/swagger/v1/swagger.json", "Purchase BFF V1");
                c.ConfigureOAuth2("Microsoft.eShopOnContainers.Mobile.Shopping.HttpAggregatorwaggerui", "", "", "Purchase BFF Swagger UI");
            });
+        }
+    }
+
+    public static class ServiceCollectionExtensions
+    {
+        public static IServiceCollection AddCustomMvc(this IServiceCollection services, IConfiguration configuration)
+        {
+            services.AddOptions();
+            services.Configure<UrlsConfig>(configuration.GetSection("urls"));
+
+            services.AddMvc();
+
+            services.AddSwaggerGen(options =>
+            {
+                options.DescribeAllEnumsAsStrings();
+                options.SwaggerDoc("v1", new Swashbuckle.AspNetCore.Swagger.Info
+                {
+                    Title = "Shopping Aggregator for Mobile Clients",
+                    Version = "v1",
+                    Description = "Shopping Aggregator for Mobile Clients",
+                    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>()
+                    {
+                        { "mobileshoppingagg", "Shopping Aggregator for Mobile Clients" }
+                    }
+                });
+
+                options.OperationFilter<AuthorizeCheckOperationFilter>();
+            });
+
+            services.AddCors(options =>
+            {
+                options.AddPolicy("CorsPolicy",
+                    builder => builder.AllowAnyOrigin()
+                    .AllowAnyMethod()
+                    .AllowAnyHeader()
+                    .AllowCredentials());
+            });
+
+            return services;
+        }
+        public static IServiceCollection AddCustomAuthentication(this IServiceCollection services, IConfiguration configuration)
+        {
+            JwtSecurityTokenHandler.DefaultInboundClaimTypeMap.Clear();
+            var identityUrl = configuration.GetValue<string>("urls:identity");
+            services.AddAuthentication(options =>
+            {
+                options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
+                options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
+
+            }).AddJwtBearer(options =>
+            {
+                options.Authority = identityUrl;
+                options.RequireHttpsMetadata = false;
+                options.Audience = "mobileshoppingagg";
+                options.Events = new JwtBearerEvents()
+                {
+                    OnAuthenticationFailed = async ctx =>
+                    {
+                        int i = 0;
+                    },
+                    OnTokenValidated = async ctx =>
+                    {
+                        int i = 0;
+                    }
+                };
+            });
+
+            return services;
+        }
+        public static IServiceCollection AddHttpServices(this IServiceCollection services)
+        {
+            //register delegating handlers
+            services.AddTransient<HttpClientAuthorizationDelegatingHandler>();
+            services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
+
+            //register http services
+            var retriesWithExponentialBackoff = HttpPolicyExtensions
+               .HandleTransientHttpError()
+               .WaitAndRetryAsync(7, retryAttempt => TimeSpan.FromSeconds(Math.Pow(2, retryAttempt)));
+
+            var circuitBreaker = HttpPolicyExtensions
+                .HandleTransientHttpError()
+                .CircuitBreakerAsync(6, TimeSpan.FromSeconds(30));
+
+            services.AddHttpClient<IBasketService, BasketService>()
+                .AddHttpMessageHandler<HttpClientAuthorizationDelegatingHandler>()
+                .AddPolicyHandler(retriesWithExponentialBackoff)
+                .AddPolicyHandler(circuitBreaker);
+
+            services.AddHttpClient<ICatalogService, CatalogService>()
+                   .AddPolicyHandler(retriesWithExponentialBackoff)
+                   .AddPolicyHandler(circuitBreaker);
+
+            services.AddHttpClient<IOrderApiClient, OrderApiClient>()
+                   .AddPolicyHandler(retriesWithExponentialBackoff)
+                   .AddPolicyHandler(circuitBreaker);
 
 
+
+            return services;
         }
     }
 }

src/ApiGateways/Web.Bff.Shopping/aggregator/Infrastructure/HttpClientAuthorizationDelegatingHandler.cs

@@ -0,0 +1,49 @@
+using Microsoft.AspNetCore.Authentication;
+using Microsoft.AspNetCore.Http;
+using System.Collections.Generic;
+using System.Net.Http;
+using System.Net.Http.Headers;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Infrastructure
+{
+    public class HttpClientAuthorizationDelegatingHandler
+         : DelegatingHandler
+    {
+        private readonly IHttpContextAccessor _httpContextAccesor;
+
+        public HttpClientAuthorizationDelegatingHandler(IHttpContextAccessor httpContextAccesor)
+        {
+            _httpContextAccesor = httpContextAccesor;
+        }
+
+        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+        {
+            var authorizationHeader = _httpContextAccesor.HttpContext
+                .Request.Headers["Authorization"];
+
+            if (!string.IsNullOrEmpty(authorizationHeader))
+            {
+                request.Headers.Add("Authorization", new List<string>() { authorizationHeader });
+            }
+
+            var token = await GetToken();
+
+            if (token != null)
+            {
+                request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
+            }
+
+            return await base.SendAsync(request, cancellationToken);
+        }
+
+        async Task<string> GetToken()
+        {
+            const string ACCESS_TOKEN = "access_token";
+
+            return await _httpContextAccesor.HttpContext
+                .GetTokenAsync(ACCESS_TOKEN);
+        }
+    }
+}

src/ApiGateways/Web.Bff.Shopping/aggregator/Services/BasketService.cs

@@ -1,53 +1,39 @@
-using System;
+using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Config;
-using System.Collections.Generic;
+using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Models;
-using System.Linq;
-using System.Threading.Tasks;
-using Microsoft.AspNetCore.Authentication;
-using Microsoft.AspNetCore.Http;
-using Microsoft.eShopOnContainers.BuildingBlocks.Resilience.Http;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using Newtonsoft.Json;
-using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Config;
+using System.Net.Http;
-using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Models;
+using System.Threading.Tasks;
 
 namespace Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Services
 {
     public class BasketService : IBasketService
     {
 
-        private readonly IHttpClient _apiClient;
+        private readonly HttpClient _apiClient;
         private readonly ILogger<BasketService> _logger;
         private readonly UrlsConfig _urls;
-        private readonly IHttpContextAccessor _httpContextAccessor;
 
-        public BasketService(IHttpClient httpClient, IHttpContextAccessor httpContextAccessor, ILogger<BasketService> logger, IOptionsSnapshot<UrlsConfig> config)
+        public BasketService(HttpClient httpClient,ILogger<BasketService> logger, IOptions<UrlsConfig> config)
         {
             _apiClient = httpClient;
             _logger = logger;
             _urls = config.Value;
-            _httpContextAccessor = httpContextAccessor;
         }
 
         public async Task<BasketData> GetById(string id)
         {
-            var token = await GetUserTokenAsync();
+            var data = await _apiClient.GetStringAsync(_urls.Basket +  UrlsConfig.BasketOperations.GetItemById(id));
-            var data = await _apiClient.GetStringAsync(_urls.Basket +  UrlsConfig.BasketOperations.GetItemById(id), token);
             var basket = !string.IsNullOrEmpty(data) ? JsonConvert.DeserializeObject<BasketData>(data) : null;
             return basket;
         }
 
         public async Task Update(BasketData currentBasket)
         {
-            var token = await GetUserTokenAsync();
+            var basketContent = new StringContent(JsonConvert.SerializeObject(currentBasket), System.Text.Encoding.UTF8, "application/json");
-            var data = await _apiClient.PostAsync<BasketData>(_urls.Basket + UrlsConfig.BasketOperations.UpdateBasket(), currentBasket, token);
-            int i = 0;
-        }
 
-        async Task<string> GetUserTokenAsync()
+            var data = await _apiClient.PostAsync(_urls.Basket + UrlsConfig.BasketOperations.UpdateBasket(), basketContent);
-        {
-            var context = _httpContextAccessor.HttpContext;
-            return await context.GetTokenAsync("access_token");
         }
     }
 }

src/ApiGateways/Web.Bff.Shopping/aggregator/Services/CatalogService.cs

@@ -1,43 +1,42 @@
-using System;
+using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Config;
-using System.Collections.Generic;
+using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Models;
-using System.Linq;
-using System.Threading.Tasks;
-using Microsoft.eShopOnContainers.BuildingBlocks.Resilience.Http;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using Newtonsoft.Json;
-using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Config;
+using System.Collections.Generic;
-using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Models;
+using System.Net.Http;
+using System.Threading.Tasks;
 
 namespace Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Services
 {
     public class CatalogService : ICatalogService
     {
 
-        private readonly IHttpClient _apiClient;
+        private readonly HttpClient _httpClient;
         private readonly ILogger<CatalogService> _logger;
         private readonly UrlsConfig _urls;
 
-        public CatalogService(IHttpClient httpClient, ILogger<CatalogService> logger, IOptionsSnapshot<UrlsConfig> config)
+        public CatalogService(HttpClient httpClient, ILogger<CatalogService> logger, IOptions<UrlsConfig> config)
         {
-            _apiClient = httpClient;
+            _httpClient = httpClient;
             _logger = logger;
             _urls = config.Value;
         }
 
         public async Task<CatalogItem> GetCatalogItem(int id)
         {
-            var data = await _apiClient.GetStringAsync(_urls.Catalog + UrlsConfig.CatalogOperations.GetItemById(id));
+            var stringContent = await _httpClient.GetStringAsync(_urls.Catalog + UrlsConfig.CatalogOperations.GetItemById(id));
-            var item = JsonConvert.DeserializeObject<CatalogItem>(data);
+            var catalogItem = JsonConvert.DeserializeObject<CatalogItem>(stringContent);
-            return item;
+
+            return catalogItem;
         }
 
         public async Task<IEnumerable<CatalogItem>> GetCatalogItems(IEnumerable<int> ids)
         {
-            var data = await _apiClient.GetStringAsync(_urls.Catalog + UrlsConfig.CatalogOperations.GetItemsById(ids));
+            var stringContent = await _httpClient.GetStringAsync(_urls.Catalog + UrlsConfig.CatalogOperations.GetItemsById(ids));
-            var item = JsonConvert.DeserializeObject<CatalogItem[]>(data);
+            var catalogItems = JsonConvert.DeserializeObject<CatalogItem[]>(stringContent);
-            return item;
 
+            return catalogItems;
         }
     }
 }

src/ApiGateways/Web.Bff.Shopping/aggregator/Services/OrderApiClient.cs

@@ -1,24 +1,21 @@
-using System;
+using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Config;
-using System.Collections.Generic;
+using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Models;
-using System.Linq;
-using System.Threading.Tasks;
-using Microsoft.eShopOnContainers.BuildingBlocks.Resilience.Http;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using Newtonsoft.Json;
-using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Config;
+using System.Net.Http;
-using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Models;
+using System.Threading.Tasks;
 
 namespace Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Services
 {
     public class OrderApiClient : IOrderApiClient
     {
 
-        private readonly IHttpClient _apiClient;
+        private readonly HttpClient _apiClient;
         private readonly ILogger<OrderApiClient> _logger;
         private readonly UrlsConfig _urls;
 
-        public OrderApiClient(IHttpClient httpClient, ILogger<OrderApiClient> logger, IOptionsSnapshot<UrlsConfig> config)
+        public OrderApiClient(HttpClient httpClient, ILogger<OrderApiClient> logger, IOptions<UrlsConfig> config)
         {
             _apiClient = httpClient;
             _logger = logger;
@@ -28,10 +25,14 @@ namespace Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Services
         public async Task<OrderData> GetOrderDraftFromBasket(BasketData basket)
         {
             var url = _urls.Orders + UrlsConfig.OrdersOperations.GetOrderDraft();
-            var response = await _apiClient.PostAsync<BasketData>(url, basket);
+            var content = new StringContent(JsonConvert.SerializeObject(basket), System.Text.Encoding.UTF8, "application/json");
+            var response = await _apiClient.PostAsync(url, content);
+
             response.EnsureSuccessStatusCode();
-            var jsonResponse = await response.Content.ReadAsStringAsync();
+
-            return JsonConvert.DeserializeObject<OrderData>(jsonResponse);
+            var ordersDraftResponse = await response.Content.ReadAsStringAsync();
+
+            return JsonConvert.DeserializeObject<OrderData>(ordersDraftResponse);
         }
     }
 }

src/ApiGateways/Web.Bff.Shopping/aggregator/Startup.cs

@@ -1,21 +1,20 @@
-using System;
+using Microsoft.AspNetCore.Authentication.JwtBearer;
-using System.Collections.Generic;
-using System.IdentityModel.Tokens.Jwt;
-using System.Linq;
-using System.Threading.Tasks;
-using Microsoft.AspNetCore.Authentication.JwtBearer;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Http;
-using Microsoft.eShopOnContainers.BuildingBlocks.Resilience.Http;
+using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Config;
+using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Filters.Basket.API.Infrastructure.Filters;
+using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Infrastructure;
+using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Services;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
-using Microsoft.Extensions.Options;
+using Polly;
-using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Config;
+using Polly.Extensions.Http;
-using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Filters.Basket.API.Infrastructure.Filters;
-using Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator.Services;
 using Swashbuckle.AspNetCore.Swagger;
+using System;
+using System.Collections.Generic;
+using System.IdentityModel.Tokens.Jwt;
 
 namespace Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator
 {
@@ -31,83 +30,14 @@ namespace Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator
         // This method gets called by the runtime. Use this method to add services to the container.
         public void ConfigureServices(IServiceCollection services)
         {
-            services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
+            services.AddCustomMvc(Configuration)
-            services.AddSingleton<IHttpClient, StandardHttpClient>();
+                .AddCustomAuthentication(Configuration)
-            services.AddTransient<ICatalogService, CatalogService>();
+                .AddApplicationServices();
-            services.AddTransient<IBasketService, BasketService>();
-            services.AddTransient<IOrderApiClient, OrderApiClient>();
-
-            services.AddOptions();
-            services.Configure<UrlsConfig>(Configuration.GetSection("urls"));
-
-            services.AddMvc();
-
-            services.AddSwaggerGen(options =>
-            {
-                options.DescribeAllEnumsAsStrings();
-                options.SwaggerDoc("v1", new Swashbuckle.AspNetCore.Swagger.Info
-                {
-                    Title = "Shopping Aggregator for Web Clients",
-                    Version = "v1",
-                    Description = "Shopping Aggregator for Web Clients",
-                    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>()
-                    {
-                        { "webshoppingagg", "Shopping Aggregator for Web Clients" }
-                    }
-                });
-
-                options.OperationFilter<AuthorizeCheckOperationFilter>();
-            });
-
-            services.AddCors(options =>
-            {
-                options.AddPolicy("CorsPolicy",
-                    builder => builder.AllowAnyOrigin()
-                    .AllowAnyMethod()
-                    .AllowAnyHeader()
-                    .AllowCredentials());
-            });
-
-
-            JwtSecurityTokenHandler.DefaultInboundClaimTypeMap.Clear();
-            var identityUrl = Configuration.GetValue<string>("urls:identity");
-            services.AddAuthentication(options =>
-            {
-                options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
-                options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
-
-            }).AddJwtBearer(options =>
-            {
-                options.Authority = identityUrl;
-                options.RequireHttpsMetadata = false;
-                options.Audience = "webshoppingagg";
-                options.Events = new JwtBearerEvents()
-                {
-                    OnAuthenticationFailed = async ctx =>
-                    {
-                        int i = 0;
-                    },
-                    OnTokenValidated = async ctx =>
-                    {
-                        int i = 0;
-                    }
-                };
-            });
         }
 
         // 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)
         {
-
             var pathBase = Configuration["PATH_BASE"];
             if (!string.IsNullOrEmpty(pathBase))
             {
@@ -135,4 +65,113 @@ namespace Microsoft.eShopOnContainers.Web.Shopping.HttpAggregator
 
         }
     }
+
+    public static class ServiceCollectionExtensions
+    {
+        public static IServiceCollection AddCustomAuthentication(this IServiceCollection services, IConfiguration configuration)
+        {
+            JwtSecurityTokenHandler.DefaultInboundClaimTypeMap.Clear();
+            var identityUrl = configuration.GetValue<string>("urls:identity");
+            services.AddAuthentication(options =>
+            {
+                options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
+                options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
+
+            }).AddJwtBearer(options =>
+            {
+                options.Authority = identityUrl;
+                options.RequireHttpsMetadata = false;
+                options.Audience = "webshoppingagg";
+                options.Events = new JwtBearerEvents()
+                {
+                    OnAuthenticationFailed = async ctx =>
+                    {
+                        int i = 0;
+                    },
+                    OnTokenValidated = async ctx =>
+                    {
+                        int i = 0;
+                    }
+                };
+            });
+
+            return services;
+        }
+        public static IServiceCollection AddCustomMvc(this IServiceCollection services, IConfiguration configuration)
+        {
+            services.AddOptions();
+            services.Configure<UrlsConfig>(configuration.GetSection("urls"));
+
+            services.AddMvc();
+
+            services.AddSwaggerGen(options =>
+            {
+                options.DescribeAllEnumsAsStrings();
+                options.SwaggerDoc("v1", new Swashbuckle.AspNetCore.Swagger.Info
+                {
+                    Title = "Shopping Aggregator for Web Clients",
+                    Version = "v1",
+                    Description = "Shopping Aggregator for Web Clients",
+                    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>()
+                    {
+                        { "webshoppingagg", "Shopping Aggregator for Web Clients" }
+                    }
+                });
+
+                options.OperationFilter<AuthorizeCheckOperationFilter>();
+            });
+
+            services.AddCors(options =>
+            {
+                options.AddPolicy("CorsPolicy",
+                    builder => builder.AllowAnyOrigin()
+                    .AllowAnyMethod()
+                    .AllowAnyHeader()
+                    .AllowCredentials());
+            });
+
+            return services;
+        }
+        public static IServiceCollection AddApplicationServices(this IServiceCollection services)
+        {
+            //register delegating handlers
+            services.AddTransient<HttpClientAuthorizationDelegatingHandler>();
+            services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
+
+            //register http services
+            var retriesWithExponentialBackoff = HttpPolicyExtensions
+               .HandleTransientHttpError()
+               .WaitAndRetryAsync(7, retryAttempt => TimeSpan.FromSeconds(Math.Pow(2, retryAttempt)));
+
+            var circuitBreaker = HttpPolicyExtensions
+                .HandleTransientHttpError()
+                .CircuitBreakerAsync(6, TimeSpan.FromSeconds(30));
+
+            services.AddHttpClient<IBasketService, BasketService>()
+                .AddHttpMessageHandler<HttpClientAuthorizationDelegatingHandler>()
+                .AddPolicyHandler(retriesWithExponentialBackoff)
+                .AddPolicyHandler(circuitBreaker);
+
+            services.AddHttpClient<ICatalogService, CatalogService>()
+                .AddPolicyHandler(retriesWithExponentialBackoff)
+                .AddPolicyHandler(circuitBreaker);
+
+            services.AddHttpClient<IOrderApiClient, OrderApiClient>()
+                .AddHttpMessageHandler<HttpClientAuthorizationDelegatingHandler>()
+                .AddPolicyHandler(retriesWithExponentialBackoff)
+                .AddPolicyHandler(circuitBreaker);
+
+
+            return services;
+        }
+    }
 }

src/ApiGateways/Web.Bff.Shopping/aggregator/Web.Shopping.HttpAggregator.csproj

@@ -15,6 +15,7 @@
     <PackageReference Include="Microsoft.AspNetCore.App" version="2.1.0-rc1-final" />
     <PackageReference Include="Swashbuckle.AspNetCore" Version="2.4.0" />
     <PackageReference Include="Swashbuckle.AspNetCore.SwaggerUi" Version="2.4.0" />
+    <PackageReference Include="Microsoft.Extensions.Http.Polly" Version="2.1.0-rc1-final" />
   </ItemGroup>
 
   <ItemGroup>