Add UseServices overload that takes a Func returning IServiceProvider

- This should be useful for third-party IoC containers

src/Microsoft.AspNet.RequestContainer/ContainerExtensions.cs

@@ -63,12 +63,20 @@ namespace Microsoft.AspNet.Builder
         }
 
         public static IBuilder UseServices(this IBuilder builder, Action<ServiceCollection> configureServices)
+        {
+            return builder.UseServices(serviceCollection =>
+            {
+                configureServices(serviceCollection);
+                return serviceCollection.BuildServiceProvider(builder.ApplicationServices);
+            });
+        }
+
+        public static IBuilder UseServices(this IBuilder builder, Func<ServiceCollection, IServiceProvider> configureServices)
         {
             var serviceCollection = new ServiceCollection();
 
             serviceCollection.Add(OptionsServices.GetDefaultServices());
-            configureServices(serviceCollection);
-            builder.ApplicationServices = serviceCollection.BuildServiceProvider(builder.ApplicationServices);
+            builder.ApplicationServices = configureServices(serviceCollection);
 
             return builder.UseMiddleware(typeof(ContainerMiddleware));
         }

test/Microsoft.AspNet.Hosting.Tests/Microsoft.AspNet.Hosting.Tests.kproj

@@ -26,6 +26,7 @@
     <Compile Include="Fakes\StartupWithServices.cs" />
     <Compile Include="HostingEngineTests.cs" />
     <Compile Include="StartupManagerTests.cs" />
+    <Compile Include="UseServicesFacts.cs" />
   </ItemGroup>
   <Import Project="$(VSToolsPath)\AspNet\Microsoft.Web.AspNet.targets" Condition="'$(VSToolsPath)' != ''" />
 </Project>

test/Microsoft.AspNet.Hosting.Tests/UseServicesFacts.cs

@@ -0,0 +1,43 @@
+using System;
+using Microsoft.AspNet.Builder;
+using Microsoft.Framework.DependencyInjection;
+using Microsoft.Framework.DependencyInjection.Fallback;
+using Microsoft.Framework.OptionsModel;
+using Xunit;
+
+namespace Microsoft.AspNet.Hosting.Tests
+{
+    public class UseServicesFacts
+    {
+        [Fact]
+        public void OptionsAccessorCanBeResolvedAfterCallingUseServicesWithAction()
+        {
+            var baseServiceProvider = new ServiceCollection().BuildServiceProvider();
+            var builder = new Microsoft.AspNet.Builder.Builder(baseServiceProvider);
+
+            builder.UseServices(serviceCollection => { });
+
+            var optionsAccessor = builder.ApplicationServices.GetService<IOptionsAccessor<object>>();
+            Assert.NotNull(optionsAccessor);
+        }
+
+
+        [Fact]
+        public void OptionsAccessorCanBeResolvedAfterCallingUseServicesWithFunc()
+        {
+            var baseServiceProvider = new ServiceCollection().BuildServiceProvider();
+            var builder = new Microsoft.AspNet.Builder.Builder(baseServiceProvider);
+            IServiceProvider serviceProvider = null;
+
+            builder.UseServices(serviceCollection =>
+            {
+                serviceProvider = serviceCollection.BuildServiceProvider(builder.ApplicationServices);
+                return serviceProvider;
+            });
+
+            Assert.Same(serviceProvider, builder.ApplicationServices);
+            var optionsAccessor = builder.ApplicationServices.GetService<IOptionsAccessor<object>>();
+            Assert.NotNull(optionsAccessor);
+        }
+    }
+}

test/Microsoft.AspNet.Hosting.Tests/project.json

@@ -2,6 +2,7 @@
   "version": "0.1-alpha-*",
   "dependencies": {
     "Microsoft.AspNet.Hosting": "",
+    "Microsoft.AspNet.RequestContainer": "",
     "xunit.abstractions": "2.0.0-aspnet-*",
     "xunit.assert": "2.0.0-aspnet-*",
     "xunit.core": "2.0.0-aspnet-*",