From cfb06c0de39599f0e922311f6795b34cc754d7e2 Mon Sep 17 00:00:00 2001
From: Yishai Galatzer <yigalatz@microsoft.com>
Date: Mon, 17 Mar 2014 23:19:34 -0700
Subject: [PATCH] Areas feature - Phase I 1. Areas defined by the Area
 attribute 2. Areas are a routeconstraint on the actiondescriptor 3. Areas
 find pages through route values

Other changes:
1. Remove Path from ActionDescriptor - It doesn't make sense with this change
2. Add sample Area
---
 .../Areas/Travel/Controllers/Flight.cs        | 13 ++++
 .../Areas/Travel/Views/Flight/Fly.cshtml      | 33 ++++++++++
 samples/MvcSample.Web/Startup.cs              |  3 +
 .../MvcSample.Web/Views/Shared/_Layout.cshtml |  5 +-
 .../ActionDescriptor.cs                       |  3 -
 .../Areas/AreaAttribute.cs                    | 17 +++++
 ...outeConstraintsActionDescriptorProvider.cs | 66 +++++++++++++++++++
 .../DefaultControllerFactory.cs               |  1 +
 .../ReflectedActionDescriptor.cs              | 12 ----
 .../ReflectedActionDescriptorProvider.cs      |  4 +-
 .../RouteConstraintAttribute.cs               | 19 ++++++
 .../Extensions/DictionaryExtensions.cs        | 21 ++++++
 .../ViewEngine/RazorViewEngine.cs             | 10 +--
 src/Microsoft.AspNet.Mvc/MvcServices.cs       |  2 +
 14 files changed, 188 insertions(+), 21 deletions(-)
 create mode 100644 samples/MvcSample.Web/Areas/Travel/Controllers/Flight.cs
 create mode 100644 samples/MvcSample.Web/Areas/Travel/Views/Flight/Fly.cshtml
 create mode 100644 src/Microsoft.AspNet.Mvc.Core/Areas/AreaAttribute.cs
 create mode 100644 src/Microsoft.AspNet.Mvc.Core/Areas/ReflectedRouteConstraintsActionDescriptorProvider.cs
 create mode 100644 src/Microsoft.AspNet.Mvc.Core/RouteConstraintAttribute.cs
 create mode 100644 src/Microsoft.AspNet.Mvc.Razor/Extensions/DictionaryExtensions.cs

diff --git a/samples/MvcSample.Web/Areas/Travel/Controllers/Flight.cs b/samples/MvcSample.Web/Areas/Travel/Controllers/Flight.cs
new file mode 100644
index 0000000000..38e5c7af80
--- /dev/null
+++ b/samples/MvcSample.Web/Areas/Travel/Controllers/Flight.cs
@@ -0,0 +1,13 @@
+using Microsoft.AspNet.Mvc;
+
+namespace MvcSample.Web
+{
+    [Area("Travel")]
+    public class Flight : Controller
+    {
+        public IActionResult Fly()
+        {
+            return View();
+        }
+    }
+}
diff --git a/samples/MvcSample.Web/Areas/Travel/Views/Flight/Fly.cshtml b/samples/MvcSample.Web/Areas/Travel/Views/Flight/Fly.cshtml
new file mode 100644
index 0000000000..ed15ba423b
--- /dev/null
+++ b/samples/MvcSample.Web/Areas/Travel/Views/Flight/Fly.cshtml
@@ -0,0 +1,33 @@
+@using MvcSample.Web.Models
+@model User
+@{
+    Layout = "/Views/Shared/_Layout.cshtml";
+    ViewBag.Title = "This is the FLY action";
+}
+
+<div class="jumbotron">
+    <h1>ASP.NET</h1>
+    <p class="lead">ASP.NET is a free web framework for building great Web sites and Web applications using HTML, CSS and JavaScript.</p>
+    <p><a href="http://asp.net" class="btn btn-primary btn-large">Learn more &raquo;</a></p>
+</div>
+<div class="row">
+    <div class="col-md-4">
+        <h2>Getting started</h2>
+        <p>
+            ASP.NET MVC gives you a powerful, patterns-based way to build dynamic websites that
+            enables a clean separation of concerns and gives you full control over markup
+            for enjoyable, agile development.
+        </p>
+        <p><a class="btn btn-default" href="http://go.microsoft.com/fwlink/?LinkId=301865">Learn more &raquo;</a></p>
+    </div>
+    <div class="col-md-4">
+        <h2>Get more libraries</h2>
+        <p>NuGet is a free Visual Studio extension that makes it easy to add, remove, and update libraries and tools in Visual Studio projects.</p>
+        <p><a class="btn btn-default" href="http://go.microsoft.com/fwlink/?LinkId=301866">Learn more &raquo;</a></p>
+    </div>
+    <div class="col-md-4">
+        <h2>Web Hosting</h2>
+        <p>You can easily find a web hosting company that offers the right mix of features and price for your applications.</p>
+        <p><a class="btn btn-default" href="http://go.microsoft.com/fwlink/?LinkId=301867">Learn more &raquo;</a></p>
+    </div>
+</div>
diff --git a/samples/MvcSample.Web/Startup.cs b/samples/MvcSample.Web/Startup.cs
index 522edda750..7ffbe7b23b 100644
--- a/samples/MvcSample.Web/Startup.cs
+++ b/samples/MvcSample.Web/Startup.cs
@@ -31,6 +31,9 @@ namespace MvcSample.Web
                 DefaultHandler = new MvcApplication(serviceProvider),
             };
 
+            // TODO: Add support for route constraints, so we can potentially constrain by existing routes
+            routes.MapRoute("{area}/{controller}/{action}");
+
             routes.MapRoute(
                 "{controller}/{action}",
                 new { controller = "Home", action = "Index" });
diff --git a/samples/MvcSample.Web/Views/Shared/_Layout.cshtml b/samples/MvcSample.Web/Views/Shared/_Layout.cshtml
index 1f7c228ce3..3377694bed 100644
--- a/samples/MvcSample.Web/Views/Shared/_Layout.cshtml
+++ b/samples/MvcSample.Web/Views/Shared/_Layout.cshtml
@@ -27,7 +27,10 @@
         @RenderBody()
         <hr />
         <address>
-            @Model.Address
+            @if (@Model != null)
+            {
+                @Model.Address
+            }
         </address>
         <footer>
             <p>&copy; @DateTime.Now.Year - My ASP.NET Application</p>
diff --git a/src/Microsoft.AspNet.Mvc.Core/ActionDescriptor.cs b/src/Microsoft.AspNet.Mvc.Core/ActionDescriptor.cs
index f45181f999..3ccb6fe024 100644
--- a/src/Microsoft.AspNet.Mvc.Core/ActionDescriptor.cs
+++ b/src/Microsoft.AspNet.Mvc.Core/ActionDescriptor.cs
@@ -3,11 +3,8 @@ using System.Diagnostics;
 
 namespace Microsoft.AspNet.Mvc
 {
-    [DebuggerDisplay("{Path}:{Name}")]
     public class ActionDescriptor
     {
-        public virtual string Path { get; set; }
-
         public virtual string Name { get; set; }
 
         public List<RouteDataActionConstraint> RouteConstraints { get; set; }
diff --git a/src/Microsoft.AspNet.Mvc.Core/Areas/AreaAttribute.cs b/src/Microsoft.AspNet.Mvc.Core/Areas/AreaAttribute.cs
new file mode 100644
index 0000000000..104160cd5f
--- /dev/null
+++ b/src/Microsoft.AspNet.Mvc.Core/Areas/AreaAttribute.cs
@@ -0,0 +1,17 @@
+using System;
+
+namespace Microsoft.AspNet.Mvc
+{
+    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = false, Inherited = true)]
+    public class AreaAttribute : RouteConstraintAttribute
+    {
+        public AreaAttribute(string areaName)
+            : base("area", areaName, blockNonAttributedActions: true)
+        {
+            if (string.IsNullOrEmpty(areaName))
+            {
+                throw new ArgumentException("Area name must not be empty", "areaName");
+            }
+        }
+    }
+}
diff --git a/src/Microsoft.AspNet.Mvc.Core/Areas/ReflectedRouteConstraintsActionDescriptorProvider.cs b/src/Microsoft.AspNet.Mvc.Core/Areas/ReflectedRouteConstraintsActionDescriptorProvider.cs
new file mode 100644
index 0000000000..425385cc2a
--- /dev/null
+++ b/src/Microsoft.AspNet.Mvc.Core/Areas/ReflectedRouteConstraintsActionDescriptorProvider.cs
@@ -0,0 +1,66 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+
+namespace Microsoft.AspNet.Mvc
+{
+    public class ReflectedRouteConstraintsActionDescriptorProvider : IActionDescriptorProvider
+    {
+        public int Order
+        {
+            get { return ReflectedActionDescriptorProvider.DefaultOrder + 100; }
+        }
+
+        public void Invoke([NotNull]ActionDescriptorProviderContext context, Action callNext)
+        {
+            var removalConstraints = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+
+            // Iterate all the Reflected Action Descriptor providers and add area or other route constraints
+            if (context.Results != null)
+            {
+                foreach (var actionDescriptor in context.Results.OfType<ReflectedActionDescriptor>())
+                {
+                    var routeConstraints = actionDescriptor.
+                                           ControllerDescriptor.
+                                           ControllerTypeInfo.
+                                           GetCustomAttributes<RouteConstraintAttribute>().
+                                           ToArray();
+
+                    foreach (var routeConstraint in routeConstraints)
+                    {
+                        if (routeConstraint.BlockNonAttributedActions)
+                        {
+                            removalConstraints.Add(routeConstraint.RouteKey);
+                        }
+
+                        // Skip on duplicates
+                        if (!ContainsKey(actionDescriptor, routeConstraint.RouteKey))
+                        {
+                            actionDescriptor.RouteConstraints.Add(new RouteDataActionConstraint(
+                                routeConstraint.RouteKey, routeConstraint.RouteValue));
+                        }
+                    }
+                }
+
+                foreach (var actionDescriptor in context.Results.OfType<ReflectedActionDescriptor>())
+                {
+                    foreach (var key in removalConstraints)
+                    {
+                        if (!ContainsKey(actionDescriptor, key))
+                        {
+                            actionDescriptor.RouteConstraints.Add(new RouteDataActionConstraint(key, RouteKeyHandling.DenyKey));
+                        }
+                    }
+                }
+            }
+
+            callNext();
+        }
+
+        private bool ContainsKey(ActionDescriptor actionDescript, string routeKey)
+        {
+            return actionDescript.RouteConstraints.Any(rc => string.Equals(rc.RouteKey, routeKey, StringComparison.OrdinalIgnoreCase));
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/Microsoft.AspNet.Mvc.Core/DefaultControllerFactory.cs b/src/Microsoft.AspNet.Mvc.Core/DefaultControllerFactory.cs
index 56b93404df..ba5fa264a3 100644
--- a/src/Microsoft.AspNet.Mvc.Core/DefaultControllerFactory.cs
+++ b/src/Microsoft.AspNet.Mvc.Core/DefaultControllerFactory.cs
@@ -4,6 +4,7 @@ using System.Reflection;
 using Microsoft.AspNet.Abstractions;
 using Microsoft.AspNet.DependencyInjection;
 using Microsoft.AspNet.Mvc.ModelBinding;
+using Microsoft.AspNet.Routing;
 using Microsoft.AspNet.Mvc.Rendering;
 
 namespace Microsoft.AspNet.Mvc
diff --git a/src/Microsoft.AspNet.Mvc.Core/ReflectedActionDescriptor.cs b/src/Microsoft.AspNet.Mvc.Core/ReflectedActionDescriptor.cs
index e0d328a5d5..7b8227cf37 100644
--- a/src/Microsoft.AspNet.Mvc.Core/ReflectedActionDescriptor.cs
+++ b/src/Microsoft.AspNet.Mvc.Core/ReflectedActionDescriptor.cs
@@ -7,18 +7,6 @@ namespace Microsoft.AspNet.Mvc
     [DebuggerDisplay("CA {Path}:{Name}(RC-{RouteConstraints.Count})")]
     public class ReflectedActionDescriptor : ActionDescriptor
     {
-        public override string Path
-        {
-            get
-            {
-                return ControllerDescriptor.Name;
-            }
-            set
-            {
-                throw new InvalidOperationException("Cannot override path");
-            }
-        }
-
         public string ControllerName
         {
             get
diff --git a/src/Microsoft.AspNet.Mvc.Core/ReflectedActionDescriptorProvider.cs b/src/Microsoft.AspNet.Mvc.Core/ReflectedActionDescriptorProvider.cs
index 1b872fb3b2..aa6729bf35 100644
--- a/src/Microsoft.AspNet.Mvc.Core/ReflectedActionDescriptorProvider.cs
+++ b/src/Microsoft.AspNet.Mvc.Core/ReflectedActionDescriptorProvider.cs
@@ -7,6 +7,8 @@ namespace Microsoft.AspNet.Mvc
 {
     public class ReflectedActionDescriptorProvider : IActionDescriptorProvider
     {
+        public static readonly int DefaultOrder = 0;
+
         private readonly IControllerAssemblyProvider _controllerAssemblyProvider;
         private readonly IActionDiscoveryConventions _conventions;
         private readonly IControllerDescriptorFactory _controllerDescriptorFactory;
@@ -30,7 +32,7 @@ namespace Microsoft.AspNet.Mvc
 
         public int Order
         {
-            get { return 0; }
+            get { return DefaultOrder; }
         }
 
         public void Invoke(ActionDescriptorProviderContext context, Action callNext)
diff --git a/src/Microsoft.AspNet.Mvc.Core/RouteConstraintAttribute.cs b/src/Microsoft.AspNet.Mvc.Core/RouteConstraintAttribute.cs
new file mode 100644
index 0000000000..cf9c4be0f8
--- /dev/null
+++ b/src/Microsoft.AspNet.Mvc.Core/RouteConstraintAttribute.cs
@@ -0,0 +1,19 @@
+using System;
+
+namespace Microsoft.AspNet.Mvc
+{
+    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = true, Inherited = true)]
+    public abstract class RouteConstraintAttribute : Attribute
+    {
+        protected RouteConstraintAttribute([NotNull]string routeKey, [NotNull]string routeValue, bool blockNonAttributedActions)
+        {
+            RouteKey = routeKey;
+            RouteValue = routeValue;
+            BlockNonAttributedActions = blockNonAttributedActions;
+        }
+
+        public string RouteKey { get; private set; }
+        public string RouteValue { get; private set; }
+        public bool BlockNonAttributedActions { get; private set; }
+    }
+}
diff --git a/src/Microsoft.AspNet.Mvc.Razor/Extensions/DictionaryExtensions.cs b/src/Microsoft.AspNet.Mvc.Razor/Extensions/DictionaryExtensions.cs
new file mode 100644
index 0000000000..754996886e
--- /dev/null
+++ b/src/Microsoft.AspNet.Mvc.Razor/Extensions/DictionaryExtensions.cs
@@ -0,0 +1,21 @@
+using Microsoft.AspNet.Mvc;
+
+namespace System.Collections.Generic
+{
+    internal static class DictionaryExtensions
+    {
+        public static T GetValueOrDefault<T>([NotNull] this IDictionary<string, object> dictionary, [NotNull] string key)
+        {
+            object valueAsObject;
+            if (dictionary.TryGetValue(key, out valueAsObject))
+            {
+                if (valueAsObject is T)
+                {
+                    return (T)valueAsObject;
+                }
+            }
+
+            return default(T);
+        }
+    }
+}
diff --git a/src/Microsoft.AspNet.Mvc.Razor/ViewEngine/RazorViewEngine.cs b/src/Microsoft.AspNet.Mvc.Razor/ViewEngine/RazorViewEngine.cs
index 9284a161a5..02ddd056ab 100644
--- a/src/Microsoft.AspNet.Mvc.Razor/ViewEngine/RazorViewEngine.cs
+++ b/src/Microsoft.AspNet.Mvc.Razor/ViewEngine/RazorViewEngine.cs
@@ -10,6 +10,8 @@ namespace Microsoft.AspNet.Mvc.Razor
     {
         private static readonly string[] _viewLocationFormats =
         {
+            "/Areas/{2}/Views/{1}/{0}.cshtml",
+            "/Areas/{2}/Views/Shared/{0}.cshtml",
             "/Views/{1}/{0}.cshtml",
             "/Views/Shared/{0}.cshtml",
         };
@@ -30,8 +32,6 @@ namespace Microsoft.AspNet.Mvc.Razor
         {
             var actionContext = (ActionContext)context;
 
-            // TODO: We plan to change this on the next CR, so we don't have a strong depenedency directly on the specific
-            // type of the action descriptor
             var actionDescriptor = actionContext.ActionDescriptor;
             
             if (actionDescriptor == null)
@@ -59,11 +59,13 @@ namespace Microsoft.AspNet.Mvc.Razor
             }
             else
             {
-                var controllerName = actionDescriptor.Path;
+                var controllerName = actionContext.RouteValues.GetValueOrDefault<string>("controller");
+                var areaName = actionContext.RouteValues.GetValueOrDefault<string>("area");
+
                 var searchedLocations = new List<string>(_viewLocationFormats.Length);
                 for (int i = 0; i < _viewLocationFormats.Length; i++)
                 {
-                    string path = String.Format(CultureInfo.InvariantCulture, _viewLocationFormats[i], viewName, controllerName);
+                    string path = String.Format(CultureInfo.InvariantCulture, _viewLocationFormats[i], viewName, controllerName, areaName);
                     IView view = await _virtualPathFactory.CreateInstance(path);
                     if (view != null)
                     {
diff --git a/src/Microsoft.AspNet.Mvc/MvcServices.cs b/src/Microsoft.AspNet.Mvc/MvcServices.cs
index cac51bdd98..ea23427838 100644
--- a/src/Microsoft.AspNet.Mvc/MvcServices.cs
+++ b/src/Microsoft.AspNet.Mvc/MvcServices.cs
@@ -41,6 +41,8 @@ namespace Microsoft.AspNet.Mvc
 
             yield return describe.Transient<INestedProvider<ActionDescriptorProviderContext>,
                                             ReflectedActionDescriptorProvider>();
+            yield return describe.Transient<INestedProvider<ActionDescriptorProviderContext>,
+                                ReflectedRouteConstraintsActionDescriptorProvider>();
             yield return describe.Transient<INestedProvider<ActionInvokerProviderContext>,
                                             ReflectedActionInvokerProvider>();