Modifying RazorViewEngine to create IRazorView instances from service

container

src/Microsoft.AspNet.Mvc.Razor/IRazorView.cs

@@ -0,0 +1,22 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using Microsoft.AspNet.Mvc.Rendering;
+
+namespace Microsoft.AspNet.Mvc.Razor
+{
+    /// <summary>
+    /// Represents the contract for an <see cref="IView"/> that executes <see cref="IRazorPage"/> as part of its
+    /// execution.
+    /// </summary>
+    public interface IRazorView : IView
+    {
+        /// <summary>
+        /// Contextualizes the current instance of the <see cref="IRazorView"/> providing it with the 
+        /// <see cref="IRazorPage"/> to execute.
+        /// </summary>
+        /// <param name="razorPage">The <see cref="IRazorPage"/> instance to execute.</param>
+        /// <param name="isPartial">Determines if the view is to be executed as a partial.</param>
+        void Contextualize(IRazorPage razorPage, bool isPartial);
+    }
+}

src/Microsoft.AspNet.Mvc.Razor/Properties/Resources.Designer.cs

@@ -234,6 +234,22 @@ namespace Microsoft.AspNet.Mvc.Razor
             return string.Format(CultureInfo.CurrentCulture, GetString("ViewContextMustBeSet"), p0, p1);
         }
 
+        /// <summary>
+        /// The '{0}' method must be called before '{1}' can be invoked.
+        /// </summary>
+        internal static string ViewMustBeContextualized
+        {
+            get { return GetString("ViewMustBeContextualized"); }
+        }
+
+        /// <summary>
+        /// The '{0}' method must be called before '{1}' can be invoked.
+        /// </summary>
+        internal static string FormatViewMustBeContextualized(object p0, object p1)
+        {
+            return string.Format(CultureInfo.CurrentCulture, GetString("ViewMustBeContextualized"), p0, p1);
+        }
+
         /// <summary>
         /// The method '{0}' cannot be invoked by this view.
         /// </summary>

src/Microsoft.AspNet.Mvc.Razor/RazorView.cs

@@ -3,56 +3,61 @@
 
 using System;
 using System.Threading.Tasks;
-using Microsoft.AspNet.Mvc.Rendering;
 
 namespace Microsoft.AspNet.Mvc.Razor
 {
     /// <summary>
-    /// Represents a <see cref="IView"/> that executes one or more <see cref="RazorPage"/> instances as part of
+    /// Default implementation for <see cref="IRazorView"/> that executes one or more <see cref="RazorPage"/> 
-    /// view rendering.
+    /// instances as part of view rendering.
     /// </summary>
-    public class RazorView : IView
+    public class RazorView : IRazorView
     {
         private readonly IRazorPageFactory _pageFactory;
         private readonly IRazorPageActivator _pageActivator;
         private readonly IViewStartProvider _viewStartProvider;
-        private readonly IRazorPage _page;
+        private IRazorPage _razorPage;
+        private bool _isPartial;
 
         /// <summary>
         /// Initializes a new instance of RazorView
         /// </summary>
-        /// <param name="page">The page to execute</param>
         /// <param name="pageFactory">The view factory used to instantiate layout and _ViewStart pages.</param>
         /// <param name="pageActivator">The <see cref="IRazorPageActivator"/> used to activate pages.</param>
-        public RazorView([NotNull] IRazorPageFactory pageFactory,
+        /// <param name="viewStartProvider">The <see cref="IViewStartProvider"/> used for discovery of _ViewStart
-                         [NotNull] IRazorPageActivator pageActivator,
+        /// pages</param>
-                         [NotNull] IViewStartProvider viewStartProvider,
+        public RazorView(IRazorPageFactory pageFactory,
-                         [NotNull] IRazorPage page)
+                         IRazorPageActivator pageActivator,
+                         IViewStartProvider viewStartProvider)
         {
             _pageFactory = pageFactory;
             _pageActivator = pageActivator;
             _viewStartProvider = viewStartProvider;
-            _page = page;
         }
 
-        /// <summary>
+        /// <inheritdoc />
-        /// Gets or sets a value that determines if the view hierarchy is executed as part of
+        public virtual void Contextualize(IRazorPage razorPage, bool isPartial)
-        /// executing the <see cref="IRazorPage"/> instance. The view hierarchy involves _ViewStart 
+        {
-        /// and Layout pages.
+            _razorPage = razorPage;
-        /// </summary>
+            _isPartial = isPartial;
-        public bool ExecuteViewHierarchy { get; set; }
+        }
 
         /// <inheritdoc />
         public virtual async Task RenderAsync([NotNull] ViewContext context)
         {
-            if (ExecuteViewHierarchy)
+            if (_razorPage == null)
             {
-                var bodyWriter = await RenderPageAsync(_page, context, executeViewStart: true);
+                var message = Resources.FormatViewMustBeContextualized(nameof(Contextualize), nameof(RenderAsync));
+                throw new InvalidOperationException(message);
+            }
+
+            if (!_isPartial)
+            {
+                var bodyWriter = await RenderPageAsync(_razorPage, context, executeViewStart: true);
                 await RenderLayoutAsync(context, bodyWriter);
             }
             else
             {
-                await RenderPageCoreAsync(_page, context);
+                await RenderPageCoreAsync(_razorPage, context);
             }
         }
 
@@ -93,14 +98,14 @@ namespace Microsoft.AspNet.Mvc.Razor
 
         private async Task RenderViewStartAsync(ViewContext context)
         {
-            var viewStarts = _viewStartProvider.GetViewStartPages(_page.Path);
+            var viewStarts = _viewStartProvider.GetViewStartPages(_razorPage.Path);
 
             foreach (var viewStart in viewStarts)
             {
                 await RenderPageCoreAsync(viewStart, context);
 
                 // Copy over interesting properties from the ViewStart page to the entry page.
-                _page.Layout = viewStart.Layout;
+                _razorPage.Layout = viewStart.Layout;
             }
         }
 
@@ -109,7 +114,7 @@ namespace Microsoft.AspNet.Mvc.Razor
         {
             // A layout page can specify another layout page. We'll need to continue
             // looking for layout pages until they're no longer specified.
-            var previousPage = _page;
+            var previousPage = _razorPage;
             while (!string.IsNullOrEmpty(previousPage.Layout))
             {
                 var layoutPage = _pageFactory.CreateInstance(previousPage.Layout);

src/Microsoft.AspNet.Mvc.Razor/RazorViewEngine.cs

@@ -31,23 +31,14 @@ namespace Microsoft.AspNet.Mvc.Razor
         };
 
         private readonly IRazorPageFactory _pageFactory;
-        private readonly ITypeActivator _typeActivator;
-        private readonly IServiceProvider _serviceProvider;
 
         /// <summary>
-        /// Initializes a new instance of the RazorViewEngine class.
+        /// Initializes a new instance of the <see cref="RazorViewEngine" /> class.
         /// </summary>
-        /// <param name="pageFactory">The page factory used for creating <see cref="IRazorPage"/>.</param>
+        /// <param name="pageFactory">The page factory used for creating <see cref="IRazorPage"/> instances.</param>
-        /// <param name="pageActivator">Activator for activated instances of <see cref="IRazorPage"/>.</param>
+        public RazorViewEngine(IRazorPageFactory pageFactory)
-        /// <param name="viewStartProvider">The provider used to provide instances of ViewStarts applicable to the 
-        /// page being rendered.</param>
-        public RazorViewEngine(IRazorPageFactory pageFactory,
-                               ITypeActivator typeActivator,
-                               IServiceProvider serviceProvider)
         {
             _pageFactory = pageFactory;
-            _typeActivator = typeActivator;
-            _serviceProvider = serviceProvider;
         }
 
         public IEnumerable<string> ViewLocationFormats
@@ -83,7 +74,7 @@ namespace Microsoft.AspNet.Mvc.Razor
                     var page = _pageFactory.CreateInstance(viewName);
                     if (page != null)
                     {
-                        return CreateFoundResult(page, viewName, partial);
+                        return CreateFoundResult(context, page, viewName, partial);
                     }
                 }
                 return ViewEngineResult.NotFound(viewName, new[] { viewName });
@@ -100,7 +91,7 @@ namespace Microsoft.AspNet.Mvc.Razor
                     var page = _pageFactory.CreateInstance(path);
                     if (page != null)
                     {
-                        return CreateFoundResult(page, path, partial);
+                        return CreateFoundResult(context, page, path, partial);
                     }
                 }
 
@@ -108,10 +99,17 @@ namespace Microsoft.AspNet.Mvc.Razor
             }
         }
 
-        private ViewEngineResult CreateFoundResult(IRazorPage page, string viewName, bool partial)
+        private ViewEngineResult CreateFoundResult(ActionContext actionContext,
+                                                   IRazorPage page,
+                                                   string viewName,
+                                                   bool partial)
         {
-            var view = _typeActivator.CreateInstance<RazorView>(_serviceProvider, page);
+            // A single request could result in creating multiple IRazorView instances (for partials, view components)
-            view.ExecuteViewHierarchy = !partial;
+            // and might store state. We'll use the service container to create new instances as we require.
+
+            var services = actionContext.HttpContext.RequestServices;
+            var view = services.GetService<IRazorView>();
+            view.Contextualize(page, partial);
             return ViewEngineResult.Found(viewName, view);
         }
 

src/Microsoft.AspNet.Mvc.Razor/Resources.resx

@@ -159,6 +159,9 @@
   <data name="ViewContextMustBeSet" xml:space="preserve">
     <value>'{0} must be set to access '{1}'.</value>
   </data>
+  <data name="ViewMustBeContextualized" xml:space="preserve">
+    <value>The '{0}' method must be called before '{1}' can be invoked.</value>
+  </data>
   <data name="View_MethodCannotBeCalled" xml:space="preserve">
     <value>The method '{0}' cannot be invoked by this view.</value>
   </data>

src/Microsoft.AspNet.Mvc/MvcServices.cs

@@ -50,6 +50,7 @@ namespace Microsoft.AspNet.Mvc
             yield return describe.Singleton<IViewEngineProvider, DefaultViewEngineProvider>();
             yield return describe.Scoped<ICompositeViewEngine, CompositeViewEngine>();
             yield return describe.Singleton<IViewStartProvider, ViewStartProvider>();
+            yield return describe.Transient<IRazorView, RazorView>();
 
             yield return describe.Singleton<IRazorPageActivator, RazorPageActivator>();
             // Virtual path view factory needs to stay scoped so views can get get scoped services.

test/Microsoft.AspNet.Mvc.Razor.Test/RazorViewEngineTest.cs

@@ -3,10 +3,9 @@
 
 using System;
 using System.Collections.Generic;
-using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Mvc.Rendering;
+using Microsoft.AspNet.PipelineCore;
 using Microsoft.AspNet.Routing;
-using Microsoft.Framework.DependencyInjection;
 using Moq;
 using Xunit;
 
@@ -183,17 +182,7 @@ namespace Microsoft.AspNet.Mvc.Razor.Test
             var page = Mock.Of<IRazorPage>();
             pageFactory.Setup(p => p.CreateInstance(It.IsAny<string>()))
                        .Returns(Mock.Of<IRazorPage>());
-
+            var viewEngine = new RazorViewEngine(pageFactory.Object);
-            var serviceProvider = new Mock<IServiceProvider>();
-            serviceProvider.Setup(p => p.GetService(typeof(IRazorPageFactory)))
-                           .Returns(pageFactory.Object);
-            serviceProvider.Setup(p => p.GetService(typeof(IRazorPageActivator)))
-                           .Returns(Mock.Of<IRazorPageActivator>());
-            serviceProvider.Setup(p => p.GetService(typeof(IViewStartProvider)))
-                           .Returns(Mock.Of<IViewStartProvider>());
-            var viewEngine = new RazorViewEngine(pageFactory.Object,
-                                                 new TypeActivator(),
-                                                 serviceProvider.Object);
             var context = GetActionContext(_controllerTestContext);
 
             // Act
@@ -201,7 +190,7 @@ namespace Microsoft.AspNet.Mvc.Razor.Test
 
             // Assert
             Assert.True(result.Success);
-            Assert.IsType<RazorView>(result.View);
+            Assert.IsAssignableFrom<IRazorView>(result.View);
             Assert.Equal("/Views/bar/test-view.cshtml", result.ViewName);
         }
 
@@ -211,16 +200,20 @@ namespace Microsoft.AspNet.Mvc.Razor.Test
             pageFactory.Setup(vpf => vpf.CreateInstance(It.IsAny<string>()))
                        .Returns<RazorPage>(null);
 
-            var viewEngine = new RazorViewEngine(pageFactory.Object,
+            var viewEngine = new RazorViewEngine(pageFactory.Object);
-                                                 Mock.Of<ITypeActivator>(),
-                                                 Mock.Of<IServiceProvider>());
 
             return viewEngine;
         }
 
-        private static ActionContext GetActionContext(IDictionary<string, object> routeValues)
+        private static ActionContext GetActionContext(IDictionary<string, object> routeValues,
+                                                      IRazorView razorView = null)
         {
-            var httpContext = Mock.Of<HttpContext>();
+            var httpContext = new DefaultHttpContext();
+            var serviceProvider = new Mock<IServiceProvider>();
+            serviceProvider.Setup(p => p.GetService(typeof(IRazorView)))
+                           .Returns(razorView ?? Mock.Of<IRazorView>());
+
+            httpContext.RequestServices = serviceProvider.Object;
             var routeData = new RouteData { Values = routeValues };
             return new ActionContext(httpContext, routeData, new ActionDescriptor());
         }

test/Microsoft.AspNet.Mvc.Razor.Test/RazorViewTest.cs

@@ -16,7 +16,24 @@ namespace Microsoft.AspNet.Mvc.Razor
         private const string LayoutPath = "~/Shared/_Layout.cshtml";
 
         [Fact]
-        public async Task RenderAsync_WithoutHierarchy_DoesNotCreateOutputBuffer()
+        public async Task RenderAsync_ThrowsIfContextualizeHasNotBeenInvoked()
+        {
+            // Arrange
+            var page = new TestableRazorPage(v => { });
+            var view = new RazorView(Mock.Of<IRazorPageFactory>(),
+                                     Mock.Of<IRazorPageActivator>(),
+                                     CreateViewStartProvider());
+            var viewContext = CreateViewContext(view);
+            var expected = viewContext.Writer;
+
+            // Act and Assert
+            var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => view.RenderAsync(viewContext));
+            Assert.Equal("The 'Contextualize' method must be called before 'RenderAsync' can be invoked.",
+                         ex.Message);
+        }
+
+        [Fact]
+        public async Task RenderAsync_AsPartial_DoesNotCreateOutputBuffer()
         {
             // Arrange
             TextWriter actual = null;
@@ -27,8 +44,8 @@ namespace Microsoft.AspNet.Mvc.Razor
             });
             var view = new RazorView(Mock.Of<IRazorPageFactory>(),
                                      Mock.Of<IRazorPageActivator>(),
-                                     CreateViewStartProvider(),
+                                     CreateViewStartProvider());
-                                     page);
+            view.Contextualize(page, isPartial: true);
             var viewContext = CreateViewContext(view);
             var expected = viewContext.Writer;
 
@@ -41,7 +58,7 @@ namespace Microsoft.AspNet.Mvc.Razor
         }
 
         [Fact]
-        public async Task RenderAsync_WithoutHierarchy_ActivatesViews_WithThePassedInViewContext()
+        public async Task RenderAsync_AsPartial_ActivatesViews_WithThePassedInViewContext()
         {
             // Arrange
             var viewData = new ViewDataDictionary(Mock.Of<IModelMetadataProvider>());
@@ -54,8 +71,8 @@ namespace Microsoft.AspNet.Mvc.Razor
 
             var view = new RazorView(Mock.Of<IRazorPageFactory>(),
                                      activator.Object,
-                                     CreateViewStartProvider(),
+                                     CreateViewStartProvider());
-                                     page);
+            view.Contextualize(page, isPartial: true);
             var viewContext = CreateViewContext(view);
             var expectedWriter = viewContext.Writer;
             activator.Setup(a => a.Activate(page, It.IsAny<ViewContext>()))
@@ -75,7 +92,7 @@ namespace Microsoft.AspNet.Mvc.Razor
         }
 
         [Fact]
-        public async Task RenderAsync_WithoutHierarchy_ActivatesViews()
+        public async Task RenderAsync_AsPartial_ActivatesViews()
         {
             // Arrange
             var page = new TestableRazorPage(v => { });
@@ -84,8 +101,8 @@ namespace Microsoft.AspNet.Mvc.Razor
                      .Verifiable();
             var view = new RazorView(Mock.Of<IRazorPageFactory>(),
                                      activator.Object,
-                                     CreateViewStartProvider(),
+                                     CreateViewStartProvider());
-                                     page);
+            view.Contextualize(page, isPartial: true);
             var viewContext = CreateViewContext(view);
 
             // Act
@@ -96,7 +113,7 @@ namespace Microsoft.AspNet.Mvc.Razor
         }
 
         [Fact]
-        public async Task RenderAsync_WithoutHierarchy_DoesNotExecuteLayoutOrViewStartPages()
+        public async Task RenderAsync_AsPartial_DoesNotExecuteLayoutOrViewStartPages()
         {
             var page = new TestableRazorPage(v =>
             {
@@ -106,8 +123,8 @@ namespace Microsoft.AspNet.Mvc.Razor
             var viewStartProvider = CreateViewStartProvider();
             var view = new RazorView(pageFactory.Object,
                                      Mock.Of<IRazorPageActivator>(),
-                                     viewStartProvider,
+                                     viewStartProvider);
-                                     page);
+            view.Contextualize(page, isPartial: true);
             var viewContext = CreateViewContext(view);
 
             // Act
@@ -119,7 +136,7 @@ namespace Microsoft.AspNet.Mvc.Razor
         }
 
         [Fact]
-        public async Task RenderAsync_WithHierarchy_CreatesOutputBuffer()
+        public async Task RenderAsync_CreatesOutputBuffer()
         {
             // Arrange
             TextWriter actual = null;
@@ -129,11 +146,8 @@ namespace Microsoft.AspNet.Mvc.Razor
             });
             var view = new RazorView(Mock.Of<IRazorPageFactory>(),
                                      Mock.Of<IRazorPageActivator>(),
-                                     CreateViewStartProvider(),
+                                     CreateViewStartProvider());
-                                     page)
+            view.Contextualize(page, isPartial: false);
-                                     {
-                                         ExecuteViewHierarchy = true
-                                     };
             var viewContext = CreateViewContext(view);
             var original = viewContext.Writer;
 
@@ -146,7 +160,7 @@ namespace Microsoft.AspNet.Mvc.Razor
         }
 
         [Fact]
-        public async Task RenderAsync_WithHierarchy_CopiesBufferedContentToOutput()
+        public async Task RenderAsync_CopiesBufferedContentToOutput()
         {
             // Arrange
             var page = new TestableRazorPage(v =>
@@ -155,11 +169,8 @@ namespace Microsoft.AspNet.Mvc.Razor
             });
             var view = new RazorView(Mock.Of<IRazorPageFactory>(),
                                      Mock.Of<IRazorPageActivator>(),
-                                     CreateViewStartProvider(),
+                                     CreateViewStartProvider());
-                                     page)
+            view.Contextualize(page, isPartial: false);
-                                     {
-                                         ExecuteViewHierarchy = true
-                                     };
             var viewContext = CreateViewContext(view);
             var original = viewContext.Writer;
 
@@ -171,7 +182,7 @@ namespace Microsoft.AspNet.Mvc.Razor
         }
 
         [Fact]
-        public async Task RenderAsync_WithHierarchy_ActivatesPages()
+        public async Task RenderAsync_ActivatesPages()
         {
             // Arrange
             var page = new TestableRazorPage(v =>
@@ -183,12 +194,9 @@ namespace Microsoft.AspNet.Mvc.Razor
                      .Verifiable();
             var view = new RazorView(Mock.Of<IRazorPageFactory>(),
                                      activator.Object,
-                                     CreateViewStartProvider(),
+                                     CreateViewStartProvider());
-                                     page)
+            view.Contextualize(page, isPartial: false);
-                                     {
+
-                                         ExecuteViewHierarchy = true
-                                     };
-                                     
             var viewContext = CreateViewContext(view);
 
             // Act
@@ -199,7 +207,7 @@ namespace Microsoft.AspNet.Mvc.Razor
         }
 
         [Fact]
-        public async Task RenderAsync_WithHierarchy_ExecutesViewStart()
+        public async Task RenderAsync_ExecutesViewStart()
         {
             // Arrange
             var actualLayoutPath = "";
@@ -228,11 +236,8 @@ namespace Microsoft.AspNet.Mvc.Razor
                      .Verifiable();
             var view = new RazorView(Mock.Of<IRazorPageFactory>(),
                                      activator.Object,
-                                     CreateViewStartProvider(viewStart1, viewStart2),
+                                     CreateViewStartProvider(viewStart1, viewStart2));
-                                     page)
+            view.Contextualize(page, isPartial: false);
-                                     {
-                                         ExecuteViewHierarchy = true
-                                     };
             var viewContext = CreateViewContext(view);
 
             // Act
@@ -243,7 +248,7 @@ namespace Microsoft.AspNet.Mvc.Razor
         }
 
         [Fact]
-        public async Task RenderAsync_WithHierarchy_ExecutesLayoutPages()
+        public async Task RenderAsync_ExecutesLayoutPages()
         {
             // Arrange
             var expected =
@@ -285,11 +290,8 @@ foot-content";
 
             var view = new RazorView(pageFactory.Object,
                                      activator.Object,
-                                     CreateViewStartProvider(),
+                                     CreateViewStartProvider());
-                                     page)
+            view.Contextualize(page, isPartial: false);
-                                     {
-                                         ExecuteViewHierarchy = true
-                                     };
             var viewContext = CreateViewContext(view);
 
             // Act
@@ -302,7 +304,7 @@ foot-content";
         }
 
         [Fact]
-        public async Task RenderAsync_WithHierarchy_ThrowsIfSectionsWereDefinedButNotRendered()
+        public async Task RenderAsync_ThrowsIfSectionsWereDefinedButNotRendered()
         {
             // Arrange
             var page = new TestableRazorPage(v =>
@@ -321,11 +323,8 @@ foot-content";
 
             var view = new RazorView(pageFactory.Object,
                                      Mock.Of<IRazorPageActivator>(),
-                                     CreateViewStartProvider(),
+                                     CreateViewStartProvider());
-                                     page)
+            view.Contextualize(page, isPartial: false);
-                                     {
-                                         ExecuteViewHierarchy = true
-                                     };
             var viewContext = CreateViewContext(view);
 
             // Act and Assert
@@ -334,7 +333,7 @@ foot-content";
         }
 
         [Fact]
-        public async Task RenderAsync_WithHierarchy_ThrowsIfBodyWasNotRendered()
+        public async Task RenderAsync_ThrowsIfBodyWasNotRendered()
         {
             // Arrange
             var page = new TestableRazorPage(v =>
@@ -350,11 +349,8 @@ foot-content";
 
             var view = new RazorView(pageFactory.Object,
                                      Mock.Of<IRazorPageActivator>(),
-                                     CreateViewStartProvider(),
+                                     CreateViewStartProvider());
-                                     page)
+            view.Contextualize(page, isPartial: false);
-                                     {
-                                         ExecuteViewHierarchy = true
-                                     };
             var viewContext = CreateViewContext(view);
 
             // Act and Assert
@@ -363,7 +359,7 @@ foot-content";
         }
 
         [Fact]
-        public async Task RenderAsync_WithHierarchy_ExecutesNestedLayoutPages()
+        public async Task RenderAsync_ExecutesNestedLayoutPages()
         {
             // Arrange
             var expected =
@@ -407,11 +403,8 @@ body-content";
 
             var view = new RazorView(pageFactory.Object,
                                      Mock.Of<IRazorPageActivator>(),
-                                     CreateViewStartProvider(),
+                                     CreateViewStartProvider());
-                                     page)
+            view.Contextualize(page, isPartial: false);
-                                     {
-                                        ExecuteViewHierarchy = true
-                                     };
             var viewContext = CreateViewContext(view);
 
             // Act