Update MVC Enumerable service registrations

Updates MVC service registration code to use the new TryAddEnumerable
overload (idempotence++).

Some other misc cleanup to improve idempotence.

src/Microsoft.AspNet.Mvc.Core/MvcCoreServiceCollectionExtensions.cs

@@ -2,8 +2,6 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
-using System.Diagnostics;
-using System.Linq;
 using Microsoft.AspNet.Mvc;
 using Microsoft.AspNet.Mvc.ActionConstraints;
 using Microsoft.AspNet.Mvc.ApplicationModels;
@@ -48,8 +46,7 @@ namespace Microsoft.Framework.DependencyInjection
         {
             // Options
             //
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IConfigureOptions<MvcOptions>, CoreMvcOptionsSetup>());
 
             // Action Discovery
@@ -57,11 +54,9 @@ namespace Microsoft.Framework.DependencyInjection
             // These are consumed only when creating action descriptors, then they can be de-allocated
             services.TryAdd(ServiceDescriptor.Transient<IAssemblyProvider, DefaultAssemblyProvider>());
             services.TryAdd(ServiceDescriptor.Transient<IControllerTypeProvider, DefaultControllerTypeProvider>()); ;
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IApplicationModelProvider, DefaultApplicationModelProvider>());
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IActionDescriptorProvider, ControllerActionDescriptorProvider>());
             services.TryAdd(ServiceDescriptor
                 .Singleton<IActionDescriptorsCollectionProvider, DefaultActionDescriptorsCollectionProvider>());
@@ -74,8 +69,7 @@ namespace Microsoft.Framework.DependencyInjection
                 .Singleton<IActionSelectorDecisionTreeProvider, ActionSelectorDecisionTreeProvider>());
             // This provider needs access to the per-request services, but might be used many times for a given
             // request.
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IActionConstraintProvider, DefaultActionConstraintProvider>());
 
             // Action Invoker
@@ -87,14 +81,11 @@ namespace Microsoft.Framework.DependencyInjection
             services.TryAdd(ServiceDescriptor.Transient<IActionInvokerFactory, ActionInvokerFactory>());
             services.TryAdd(ServiceDescriptor
                 .Transient<IControllerActionArgumentBinder, DefaultControllerActionArgumentBinder>());
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IActionInvokerProvider, ControllerActionInvokerProvider>());
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IFilterProvider, DefaultFilterProvider>());
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IControllerPropertyActivator, DefaultControllerPropertyActivator>());
 
             // ModelBinding, Validation and Formatting
@@ -127,34 +118,14 @@ namespace Microsoft.Framework.DependencyInjection
             services.TryAdd(ServiceDescriptor.Scoped<IUrlHelper, UrlHelper>());
         }
 
-        // Adds a service if the service type and implementation type hasn't been added yet. This is needed for
-        // services like IConfigureOptions<MvcOptions> or IApplicationModelProvider where you need the ability
-        // to register multiple implementation types for the same service type.
-        private static bool TryAddMultiRegistrationService(IServiceCollection services, ServiceDescriptor descriptor)
-        {
-            // This can't work when registering a factory or instance, you have to register a type.
-            // Additionally, if any existing registrations use a factory or instance, we can't check those, but we don't
-            // assert that because it might be added by user-code.
-            Debug.Assert(descriptor.ImplementationType != null);
-
-            if (services.Any(d =>
-                d.ServiceType == descriptor.ServiceType &&
-                d.ImplementationType == descriptor.ImplementationType))
-            {
-                return false;
-            }
-
-            services.Add(descriptor);
-            return true;
-        }
-
         private static void ConfigureDefaultServices(IServiceCollection services)
         {
             services.AddOptions();
             services.AddRouting();
             services.AddNotifier();
-            services.Configure<RouteOptions>(
-                routeOptions => routeOptions.ConstraintMap.Add("exists", typeof(KnownRouteValueConstraint)));
+
+            services.TryAddEnumerable(
+                ServiceDescriptor.Transient<IConfigureOptions<RouteOptions>, MvcRouteOptionsSetup>());
         }
     }
 }

src/Microsoft.AspNet.Mvc.Core/MvcRouteOptionsSetup.cs

@@ -0,0 +1,29 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using Microsoft.AspNet.Routing;
+using Microsoft.Framework.OptionsModel;
+
+namespace Microsoft.AspNet.Mvc
+{
+    /// <summary>
+    /// Sets up MVC default options for <see cref="RouteOptions"/>.
+    /// </summary>
+    public class MvcRouteOptionsSetup : ConfigureOptions<RouteOptions>
+    {
+        public MvcRouteOptionsSetup()
+            : base(ConfigureRouting)
+        {
+            Order = DefaultOrder.DefaultFrameworkSortOrder;
+        }
+
+        /// <summary>
+        /// Configures the <see cref="RouteOptions"/>.
+        /// </summary>
+        /// <param name="options">The <see cref="RouteOptions"/>.</param>
+        public static void ConfigureRouting(RouteOptions options)
+        {
+            options.ConstraintMap.Add("exists", typeof(KnownRouteValueConstraint));
+        }
+    }
+}

src/Microsoft.AspNet.Mvc.WebApiCompatShim/WebApiCompatShimOptionsSetup.cs

@@ -1,6 +1,7 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System.Net.Http;
 using System.Net.Http.Formatting;
 using Microsoft.Framework.OptionsModel;
 
@@ -35,6 +36,8 @@ namespace Microsoft.AspNet.Mvc.WebApiCompatShim
 
             // Add a formatter to write out an HttpResponseMessage to the response
             options.OutputFormatters.Insert(0, new HttpResponseMessageOutputFormatter());
+
+            options.ValidationExcludeFilters.Add(typeof(HttpResponseMessage));
         }
 
         public void Configure(WebApiCompatShimOptions options, string name = "")

src/Microsoft.AspNet.Mvc.WebApiCompatShim/WebApiCompatShimServiceCollectionExtensions.cs

@@ -1,10 +1,10 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using System.Net.Http;
 using System.Net.Http.Formatting;
 using Microsoft.AspNet.Mvc;
 using Microsoft.AspNet.Mvc.WebApiCompatShim;
+using Microsoft.Framework.OptionsModel;
 
 namespace Microsoft.Framework.DependencyInjection
 {
@@ -12,15 +12,14 @@ namespace Microsoft.Framework.DependencyInjection
     {
         public static IServiceCollection AddWebApiConventions(this IServiceCollection services)
         {
-            services.ConfigureOptions<WebApiCompatShimOptionsSetup>();
+            services.TryAddEnumerable(
+                ServiceDescriptor.Transient<IConfigureOptions<MvcOptions>, WebApiCompatShimOptionsSetup>());
+            services.TryAddEnumerable(
+                ServiceDescriptor.Transient<IConfigureOptions<WebApiCompatShimOptions>, WebApiCompatShimOptionsSetup>());
 
             // The constructors on DefaultContentNegotiator aren't DI friendly, so just
             // new it up.
-            services.AddInstance<IContentNegotiator>(new DefaultContentNegotiator());
-            services.Configure<MvcOptions>(options =>
-            {
-                options.ValidationExcludeFilters.Add(typeof(HttpRequestMessage));
-            });
+            services.TryAdd(ServiceDescriptor.Instance<IContentNegotiator>(new DefaultContentNegotiator()));
 
             return services;
         }

src/Microsoft.AspNet.Mvc/MvcServiceCollectionExtensions.cs

@@ -145,38 +145,30 @@ namespace Microsoft.Framework.DependencyInjection
         internal static void AddMvcServices(IServiceCollection services)
         {
             // Options - all of these are multi-registration
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IConfigureOptions<MvcOptions>, MvcOptionsSetup>());
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IConfigureOptions<MvcOptions>, JsonMvcOptionsSetup>());
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor
                 .Transient<IConfigureOptions<MvcFormatterMappingOptions>, JsonMvcFormatterMappingOptionsSetup>());
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IConfigureOptions<MvcViewOptions>, MvcViewOptionsSetup>());
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor
                 .Transient<IConfigureOptions<RazorViewEngineOptions>, RazorViewEngineOptionsSetup>());
 
             // Cors
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IApplicationModelProvider, CorsApplicationModelProvider>());
             services.TryAdd(ServiceDescriptor.Transient<CorsAuthorizationFilter, CorsAuthorizationFilter>());
 
             // Auth
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IApplicationModelProvider, AuthorizationApplicationModelProvider>());
 
             // Support for activating ViewDataDictionary
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor
                     .Transient<IControllerPropertyActivator, ViewDataDictionaryControllerPropertyActivator>());
 
@@ -264,8 +256,7 @@ namespace Microsoft.Framework.DependencyInjection
             // Api Description
             services.TryAdd(ServiceDescriptor
                 .Singleton<IApiDescriptionGroupCollectionProvider, ApiDescriptionGroupCollectionProvider>());
-            TryAddMultiRegistrationService(
-                services,
+            services.TryAddEnumerable(
                 ServiceDescriptor.Transient<IApiDescriptionProvider, DefaultApiDescriptionProvider>());
         }
 
@@ -297,27 +288,6 @@ namespace Microsoft.Framework.DependencyInjection
             return services;
         }
 
-        // Adds a service if the service type and implementation type hasn't been added yet. This is needed for
-        // services like IConfigureOptions<MvcOptions> or IApplicationModelProvider where you need the ability
-        // to register multiple implementation types for the same service type.
-        private static bool TryAddMultiRegistrationService(IServiceCollection services, ServiceDescriptor descriptor)
-        {
-            // This can't work when registering a factory or instance, you have to register a type.
-            // Additionally, if any existing registrations use a factory or instance, we can't check those, but we don't
-            // assert that because it might be added by user-code.
-            Debug.Assert(descriptor.ImplementationType != null);
-
-            if (services.Any(d =>
-                d.ServiceType == descriptor.ServiceType &&
-                d.ImplementationType == descriptor.ImplementationType))
-            {
-                return false;
-            }
-
-            services.Add(descriptor);
-            return true;
-        }
-
         private static void ConfigureDefaultServices(IServiceCollection services)
         {
             services.AddDataProtection();