Merge pull request #155 from martincostello/Refactor-Initialization

Refactor initialization

src/LondonTravel.Skill/AlexaFunction.cs

@@ -6,7 +6,13 @@
 using Alexa.NET.Request;
 using Alexa.NET.Response;
 using Amazon.Lambda.Core;
+using MartinCostello.LondonTravel.Skill.Extensions;
+using MartinCostello.LondonTravel.Skill.Intents;
+using Microsoft.ApplicationInsights;
+using Microsoft.ApplicationInsights.Extensibility;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.DependencyInjection.Extensions;
+using Microsoft.Extensions.Logging;
 
 namespace MartinCostello.LondonTravel.Skill
 {
@@ -15,6 +21,18 @@ namespace MartinCostello.LondonTravel.Skill
     /// </summary>
     public class AlexaFunction
     {
+        /// <summary>
+        /// The <see cref="IServiceProvider"/> to use.
+        /// </summary>
+        private IServiceProvider _serviceProvider;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AlexaFunction"/> class.
+        /// </summary>
+        public AlexaFunction()
+        {
+        }
+
         /// <summary>
         /// Handles a request to the skill as an asynchronous operation.
         /// </summary>
@@ -27,20 +45,99 @@ public async Task<SkillResponse> HandlerAsync(SkillRequest request, ILambdaConte
         {
             context.Logger.LogLine($"Invoking skill request of type {request.Request.GetType().Name}.");
 
-            IServiceProvider serviceProvider = CreateServiceProvider();
-
-            var handler = serviceProvider.GetRequiredService<FunctionHandler>();
+            var handler = _serviceProvider.GetRequiredService<FunctionHandler>();
 
             return await handler.HandleAsync(request);
         }
 
+        /// <summary>
+        /// Initializes the skill as an asynchronous operation.
+        /// </summary>
+        /// <returns>
+        /// A <see cref="Task{TResult}"/> representing the asynchronous operation to initialize the skill.
+        /// </returns>
+        public Task<bool> InitializeAsync()
+        {
+            if (_serviceProvider == null)
+            {
+                _serviceProvider = CreateServiceProvider();
+            }
+
+            return Task.FromResult(true);
+        }
+
         /// <summary>
         /// Configures the <see cref="IServiceCollection"/> to use.
         /// </summary>
         /// <param name="services">The service collection to configure.</param>
         protected virtual void ConfigureServices(IServiceCollection services)
         {
-            // No-op
+            services.AddLogging((builder) =>
+            {
+                var options = new LambdaLoggerOptions()
+                {
+                    Filter = FilterLogs,
+                };
+
+                builder.AddLambdaLogger(options);
+            });
+
+            services.AddHttpClients();
+            services.AddPolly();
+
+            services.TryAddSingleton((_) => SkillConfiguration.CreateDefaultConfiguration());
+
+            services.AddSingleton<AlexaSkill>();
+            services.AddSingleton<FunctionHandler>();
+            services.AddSingleton<IntentFactory>();
+            services.AddSingleton((_) => TelemetryConfiguration.CreateDefault());
+            services.AddSingleton(CreateTelemetryClient);
+
+            services.AddSingleton<EmptyIntent>();
+            services.AddSingleton<HelpIntent>();
+            services.AddSingleton<UnknownIntent>();
+
+            services.AddTransient<CommuteIntent>();
+            services.AddTransient<DisruptionIntent>();
+            services.AddTransient<StatusIntent>();
+        }
+
+        /// <summary>
+        /// Creates an <see cref="TelemetryClient"/>.
+        /// </summary>
+        /// <param name="serviceProvider">The <see cref="IServiceProvider"/> to use.</param>
+        /// <returns>
+        /// The created instance of <see cref="TelemetryClient"/>.
+        /// </returns>
+        private static TelemetryClient CreateTelemetryClient(IServiceProvider serviceProvider)
+        {
+            var config = serviceProvider.GetRequiredService<SkillConfiguration>();
+            var configuration = serviceProvider.GetRequiredService<TelemetryConfiguration>();
+
+            return new TelemetryClient(configuration)
+            {
+                InstrumentationKey = config.ApplicationInsightsKey,
+            };
+        }
+
+        /// <summary>
+        /// Filters the Lambda logs.
+        /// </summary>
+        /// <param name="name">The name of the log.</param>
+        /// <param name="level">The log level.</param>
+        /// <returns>
+        /// <see langword="true"/> to log the message; otherwise <see langword="false"/>.
+        /// </returns>
+        private static bool FilterLogs(string name, LogLevel level)
+        {
+            if (level < LogLevel.Warning &&
+                (name.StartsWith("System.", StringComparison.Ordinal) ||
+                 name.StartsWith("Microsoft.", StringComparison.Ordinal)))
+            {
+                return false;
+            }
+
+            return true;
         }
 
         /// <summary>
@@ -51,7 +148,11 @@ protected virtual void ConfigureServices(IServiceCollection services)
         /// </returns>
         private IServiceProvider CreateServiceProvider()
         {
-            return ServiceResolver.GetServiceCollection(ConfigureServices).BuildServiceProvider();
+            var services = new ServiceCollection();
+
+            ConfigureServices(services);
+
+            return services.BuildServiceProvider();
         }
     }
 }

src/LondonTravel.Skill/Function.cs → src/LondonTravel.Skill/FunctionEntrypoint.cs

@@ -17,7 +17,7 @@ namespace MartinCostello.LondonTravel.Skill
     /// <remarks>
     /// See https://aws.amazon.com/blogs/developer/announcing-amazon-lambda-runtimesupport/.
     /// </remarks>
-    internal static class Function
+    public static class FunctionEntrypoint
     {
         /// <summary>
         /// Runs the function using a custom runtime as an asynchronous operation.
@@ -27,15 +27,15 @@ internal static class Function
         /// <returns>
         /// A <see cref="Task"/> representing the asynchronous operation to run the function.
         /// </returns>
-        internal static async Task RunAsync(
+        public static async Task RunAsync(
             HttpClient httpClient = null,
             CancellationToken cancellationToken = default)
         {
             var serializer = new JsonSerializer();
             var function = new AlexaFunction();
 
             using var handlerWrapper = HandlerWrapper.GetHandlerWrapper<SkillRequest, SkillResponse>(function.HandlerAsync, serializer);
-            using var bootstrap = new LambdaBootstrap(httpClient ?? new HttpClient(), handlerWrapper);
+            using var bootstrap = new LambdaBootstrap(httpClient ?? new HttpClient(), handlerWrapper, function.InitializeAsync);
 
             await bootstrap.RunAsync(cancellationToken);
         }

test/LondonTravel.Skill.Tests/AlexaFunctionTests.cs

@@ -24,7 +24,7 @@ public AlexaFunctionTests(ITestOutputHelper outputHelper)
         public async Task Cannot_Invoke_Function_If_Application_Id_Incorrect()
         {
             // Arrange
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
 
             SkillRequest request = CreateIntentRequest("AMAZON.HelpIntent");
             request.Session.Application.ApplicationId = "not-my-skill-id";
@@ -48,7 +48,7 @@ public async Task Cannot_Invoke_Function_If_Application_Id_Incorrect()
         public async Task Can_Invoke_Function_If_Locale_Is_Invalid(string locale)
         {
             // Arrange
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
 
             SkillRequest request = CreateIntentRequest("AMAZON.HelpIntent");
             request.Request.Locale = locale;
@@ -69,7 +69,7 @@ public async Task Can_Invoke_Function_If_Locale_Is_Invalid(string locale)
         public async Task Cannot_Invoke_Function_With_System_Failure()
         {
             // Arrange
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
             ILambdaContext context = CreateContext();
 
             var error = new SystemExceptionRequest()

test/LondonTravel.Skill.Tests/CancelTests.cs

@@ -22,7 +22,7 @@ public CancelTests(ITestOutputHelper outputHelper)
         public async Task Can_Invoke_Function()
         {
             // Arrange
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
 
             SkillRequest request = CreateIntentRequest("AMAZON.CancelIntent");
             ILambdaContext context = CreateContext();

test/LondonTravel.Skill.Tests/CommuteTests.cs

@@ -25,7 +25,7 @@ public CommuteTests(ITestOutputHelper outputHelper)
         public async Task Can_Invoke_Function_When_The_Skill_Is_Not_Linked()
         {
             // Arrange
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
             SkillRequest request = CreateIntentRequestWithToken(accessToken: null);
             ILambdaContext context = CreateContext();
 
@@ -53,7 +53,7 @@ public async Task Can_Invoke_Function_When_The_Skill_Token_Is_Invalid()
             // Arrange
             Interceptor.RegisterBundle(Path.Combine("Bundles", "skill-api-invalid-token.json"));
 
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
             SkillRequest request = CreateIntentRequestWithToken(accessToken: "invalid-access-token");
             ILambdaContext context = CreateContext();
 
@@ -79,7 +79,7 @@ public async Task Can_Invoke_Function_When_The_Skill_Token_Is_Invalid()
         public async Task Can_Invoke_Function_When_The_Skill_Api_Fails()
         {
             // Arrange
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
             SkillRequest request = CreateIntentRequestWithToken(accessToken: "random-access-token");
             ILambdaContext context = CreateContext();
 
@@ -106,7 +106,7 @@ public async Task Can_Invoke_Function_When_The_Skill_Is_Linked_And_Has_No_Favori
             Interceptor.RegisterBundle(Path.Combine("Bundles", "skill-api-no-favorites.json"));
             Interceptor.RegisterBundle(Path.Combine("Bundles", "tfl-line-statuses.json"));
 
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
             SkillRequest request = CreateIntentRequestWithToken(accessToken: "token-for-no-favorites");
             ILambdaContext context = CreateContext();
 
@@ -127,7 +127,7 @@ public async Task Can_Invoke_Function_When_The_Skill_Is_Linked_And_Only_The_Eliz
             Interceptor.RegisterBundle(Path.Combine("Bundles", "skill-api-elizabeth.json"));
             Interceptor.RegisterBundle(Path.Combine("Bundles", "tfl-line-statuses.json"));
 
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
             SkillRequest request = CreateIntentRequestWithToken(accessToken: "token-for-only-elizabeth-line");
             ILambdaContext context = CreateContext();
 
@@ -148,7 +148,7 @@ public async Task Can_Invoke_Function_When_The_Skill_Is_Linked_And_Has_One_Favor
             Interceptor.RegisterBundle(Path.Combine("Bundles", "skill-api-one-favorite.json"));
             Interceptor.RegisterBundle(Path.Combine("Bundles", "tfl-line-statuses.json"));
 
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
             SkillRequest request = CreateIntentRequestWithToken(accessToken: "token-for-one-favorite");
             ILambdaContext context = CreateContext();
 
@@ -169,7 +169,7 @@ public async Task Can_Invoke_Function_When_The_Skill_Is_Linked_And_Has_Two_Favor
             Interceptor.RegisterBundle(Path.Combine("Bundles", "skill-api-two-favorites.json"));
             Interceptor.RegisterBundle(Path.Combine("Bundles", "tfl-line-statuses.json"));
 
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
             SkillRequest request = CreateIntentRequestWithToken(accessToken: "token-for-two-favorites");
             ILambdaContext context = CreateContext();
 

test/LondonTravel.Skill.Tests/DisruptionTests.cs

@@ -26,7 +26,7 @@ public async Task Can_Invoke_Function_When_There_Are_No_Disruptions()
             // Arrange
             Interceptor.RegisterBundle(Path.Combine("Bundles", "tfl-no-disruptions.json"));
 
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
             SkillRequest request = CreateIntentRequest();
             ILambdaContext context = CreateContext();
 
@@ -46,7 +46,7 @@ public async Task Can_Invoke_Function_When_There_Is_One_Disruption()
             // Arrange
             Interceptor.RegisterBundle(Path.Combine("Bundles", "tfl-one-disruption.json"));
 
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
             SkillRequest request = CreateIntentRequest();
             ILambdaContext context = CreateContext();
 
@@ -66,7 +66,7 @@ public async Task Can_Invoke_Function_When_There_Are_Multiple_Disruptions()
             // Arrange
             Interceptor.RegisterBundle(Path.Combine("Bundles", "tfl-multiple-disruptions.json"));
 
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
             SkillRequest request = CreateIntentRequest();
             ILambdaContext context = CreateContext();
 
@@ -84,7 +84,7 @@ public async Task Can_Invoke_Function_When_There_Are_Multiple_Disruptions()
         public async Task Can_Invoke_Function_When_The_Api_Fails()
         {
             // Arrange
-            AlexaFunction function = CreateFunction();
+            AlexaFunction function = await CreateFunctionAsync();
             SkillRequest request = CreateIntentRequest();
             ILambdaContext context = CreateContext();