Productize HttpMethodEndpointSelector (#463)

Addresses #452

samples/DispatcherSample/Startup.cs

@@ -7,11 +7,9 @@ using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Dispatcher;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Http;
-using Microsoft.AspNetCore.Routing;
 using Microsoft.AspNetCore.Routing.Dispatcher;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
-using Microsoft.Extensions.Options;
 
 namespace DispatcherSample
 {

src/Microsoft.AspNetCore.Dispatcher/HttpMethodEndpointSelector.cs

@@ -4,9 +4,8 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
-using Microsoft.AspNetCore.Dispatcher;
 
-namespace DispatcherSample
+namespace Microsoft.AspNetCore.Dispatcher
 {
     public class HttpMethodEndpointSelector : EndpointSelector
     {
@@ -19,19 +18,19 @@ namespace DispatcherSample
 
             var snapshot = context.CreateSnapshot();
 
-            var fallback = new List<Endpoint>();
+            var fallbackEndpoints = new List<Endpoint>();
             for (var i = context.Endpoints.Count - 1; i >= 0; i--)
             {
                 var endpoint = context.Endpoints[i] as ITemplateEndpoint;
                 if (endpoint == null || endpoint.HttpMethod == null)
                 {
                     // No metadata.
-                    fallback.Add(context.Endpoints[i]);
+                    fallbackEndpoints.Add(context.Endpoints[i]);
                     context.Endpoints.RemoveAt(i);
                 }
                 else if (string.Equals(endpoint.HttpMethod, context.HttpContext.Request.Method, StringComparison.OrdinalIgnoreCase))
                 {
-                    // This one matches.
+                    // The request method matches the endpoint's HTTP method.
                 }
                 else
                 {
@@ -50,9 +49,9 @@ namespace DispatcherSample
                 context.RestoreSnapshot(snapshot);
                 context.Endpoints.Clear();
 
-                for (var i = 0; i < fallback.Count; i++)
+                for (var i = 0; i < fallbackEndpoints.Count; i++)
                 {
-                    context.Endpoints.Add(fallback[i]);
+                    context.Endpoints.Add(fallbackEndpoints[i]);
                 }
 
                 await context.InvokeNextAsync();

src/Microsoft.AspNetCore.Routing/Dispatcher/TreeDispatcher.cs

@@ -167,7 +167,7 @@ namespace Microsoft.AspNetCore.Routing.Dispatcher
                     trees.Add(new UrlMatchingTree(trees.Count));
                 }
 
-                var tree = trees[i];
+                var tree = trees[entry.Order];
 
                 TreeRouteBuilder.AddEntryToTree(tree, entry);
             }

test/Microsoft.AspNetCore.Dispatcher.FunctionalTest/ApiAppStartup.cs

@@ -62,15 +62,31 @@ namespace Microsoft.AspNetCore.Dispatcher.FunctionalTest
             {
                 Endpoints =
                 {
-                    new TemplateEndpoint("api/products", Products_Get),
+                    new TemplateEndpoint("api/products", Products_Fallback),
+                    new TemplateEndpoint("api/products", new { controller = "Products", action = "Get", }, "GET", Products_Get),
+                    new TemplateEndpoint("api/products/{id}", new { controller = "Products", action = "Get", }, "GET", Products_GetWithId),
+                    new TemplateEndpoint("api/products", new { controller = "Products", action = "Post", }, "POST", Products_Post),
+                    new TemplateEndpoint("api/products/{id}", new { controller = "Products", action = "Put", }, "PUT", Products_Put),
                 },
-            });
 
+                Selectors =
+                {
+                    new HttpMethodEndpointSelector(),
+                }
+            });
             options.HandlerFactories.Add(endpoint => (endpoint as TemplateEndpoint)?.HandlerFactory);
         }
 
+        private Task Products_Fallback(HttpContext httpContext) => httpContext.Response.WriteAsync("Hello, Products_Fallback");
+
         private Task Products_Get(HttpContext httpContext) => httpContext.Response.WriteAsync("Hello, Products_Get");
 
+        private Task Products_GetWithId(HttpContext httpContext) => httpContext.Response.WriteAsync("Hello, Products_GetWithId");
+
+        private Task Products_Post(HttpContext httpContext) => httpContext.Response.WriteAsync("Hello, Products_Post");
+
+        private Task Products_Put(HttpContext httpContext) => httpContext.Response.WriteAsync("Hello, Products_Put");
+
         private class CorsPolicyMetadata
         {
             public string Name { get; set; }

test/Microsoft.AspNetCore.Dispatcher.FunctionalTest/ApiAppTest.cs

@@ -30,5 +30,73 @@ namespace Microsoft.AspNetCore.Dispatcher.FunctionalTest
             Assert.Equal(HttpStatusCode.OK, response.StatusCode);
             Assert.Equal("Hello, Products_Get", await response.Content.ReadAsStringAsync());
         }
+
+        [Fact]
+        public async Task ApiApp_RoutesTo_EndpointWithMatchingHttpMethod()
+        {
+            // Arrange
+            var request = new HttpRequestMessage(HttpMethod.Post, "/api/products");
+
+            // Act
+            var response = await Client.SendAsync(request);
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            Assert.Equal("Hello, Products_Post", await response.Content.ReadAsStringAsync());
+        }
+
+        [Fact]
+        public async Task ApiApp_RoutesTo_EndpointWithMatchingHttpMethod_AndMatchingRoute()
+        {
+            // Arrange
+            var request = new HttpRequestMessage(HttpMethod.Get, "/api/products/3");
+
+            // Act
+            var response = await Client.SendAsync(request);
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            Assert.Equal("Hello, Products_GetWithId", await response.Content.ReadAsStringAsync());
+        }
+
+        [Fact]
+        public async Task ApiApp_RoutesTo_EndpointWithMatchingHttpMethod_DoesNotMatchExpectedRoute()
+        {
+            // Arrange
+            var request = new HttpRequestMessage(HttpMethod.Put, "/api/services/2");
+
+            // Act
+            var response = await Client.SendAsync(request);
+
+            // Assert
+            Assert.Equal(HttpStatusCode.NotFound, response.StatusCode);
+        }
+
+        [Fact]
+        public async Task ApiApp_NoEndpointWithMatchingHttpMethod_FallbackEndpointSelected()
+        {
+            // Arrange
+            var request = new HttpRequestMessage(HttpMethod.Delete, "/api/products");
+
+            // Act
+            var response = await Client.SendAsync(request);
+
+            // Assert
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            Assert.Equal("Hello, Products_Fallback", await response.Content.ReadAsStringAsync());
+        }
+        
+        [Fact]
+        public async Task ApiApp_NoEndpointWithMatchingHttpMethod_NoFallbackEndpointMatched()
+        {
+            // Arrange
+            var request = new HttpRequestMessage(HttpMethod.Delete, "/api/products/4");
+
+            // Act
+            var response = await Client.SendAsync(request);
+
+            // Assert
+            Assert.Equal(HttpStatusCode.NotFound, response.StatusCode);
+        }
     }
 }

test/Microsoft.AspNetCore.Dispatcher.Test/DispatcherTest.cs

@@ -1,16 +0,0 @@
-// 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 Xunit;
-
-namespace Microsoft.AspNetCore.Dispatcher.Abstractions.Test
-{
-    public class DispatcherTest
-    {
-        [Fact]
-        public void Test()
-        {
-
-        }
-    }
-}

test/Microsoft.AspNetCore.Dispatcher.Test/HttpMethodEndpointSelectorTest.cs

@@ -0,0 +1,101 @@
+// 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.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Http;
+using Xunit;
+
+namespace Microsoft.AspNetCore.Dispatcher
+{
+    public class HttpMethodEndpointSelectorTest
+    {
+        [Theory]
+        [InlineData("get")]
+        [InlineData("Get")]
+        [InlineData("GET")]
+        public async Task RequestMethod_MatchesEndpointMethod_IgnoresCase(string httpMethod)
+        {
+            // Arrange
+            var endpoints = new List<Endpoint>()
+            {
+                new TemplateEndpoint("{controller=Home}/{action=Index}/{id?}", new { controller = "Products", action = "Get", }, "GET", Products_Get, "Products:Get()"),
+                new TemplateEndpoint("{controller=Home}/{action=Index}/{id?}", new { controller = "Products", action = "Create", }, "POST", Products_Post, "Products:Post()"),
+            };
+
+            var (context, selector) = CreateContextAndSelector(httpMethod, endpoints);
+
+            // Act
+            await selector.SelectAsync(context);
+            var templateEndpoints = context.Endpoints.Cast<TemplateEndpoint>();
+
+            // Assert
+            Assert.Collection(
+                templateEndpoints,
+                endpoint => Assert.Equal(httpMethod.ToUpperInvariant(), endpoint.HttpMethod));
+        }
+
+        [Fact]
+        public async Task RequestMethod_DoesNotMatch_AnyEndpointMethod()
+        {
+            // Arrange
+            var endpoints = new List<Endpoint>()
+            {
+                new TemplateEndpoint("{controller=Home}/{action=Index}/{id?}", new { controller = "Products", action = "Get", }, "GET", Products_Get, "Products:Get()"),
+                new TemplateEndpoint("{controller=Home}/{action=Index}/{id?}", new { controller = "Products", action = "Create", }, "POST", Products_Post, "Products:Post()"),
+            };
+
+            var (context, selector) = CreateContextAndSelector("PUT", endpoints);
+
+            // Act
+            await selector.SelectAsync(context);
+
+            // Assert
+            Assert.Equal(0, context.Endpoints.Count);
+        }
+
+        [Theory]
+        [InlineData("PUT")]
+        [InlineData(null)]
+        public async Task RequestMethod_NotSpecifiedOrNotFound_ReturnsFallbackEndpointMethod(string httpMethod)
+        {
+            // Arrange
+            var endpoints = new List<Endpoint>()
+            {
+                new TemplateEndpoint("{controller=Home}/{action=Index}/{id?}", new { controller = "Products", action = "Get", }, "GET", Products_Get, "Products:Get()"),
+                new TemplateEndpoint("{controller=Home}/{action=Index}/{id?}", new { controller = "Products", action = "Create", }, "POST", Products_Post, "Products:Post()"),
+                new TemplateEndpoint("{controller=Home}/{action=Index}/{id?}", new { controller = "Products", action = "Get", }, Products_Get),
+            };
+
+            var (context, selector) = CreateContextAndSelector(httpMethod, endpoints);
+
+            // Act
+            await selector.SelectAsync(context);
+            var templateEndpoints = context.Endpoints.Cast<TemplateEndpoint>();
+
+            // Assert
+            Assert.Collection(
+                templateEndpoints,
+                endpoint => Assert.Null(endpoint.HttpMethod));
+        }
+
+        private (EndpointSelectorContext, EndpointSelector) CreateContextAndSelector(string httpMethod, List<Endpoint> endpoints)
+        {
+            var httpContext = new DefaultHttpContext();
+            httpContext.Request.Method = httpMethod;
+            var selector = new HttpMethodEndpointSelector();
+            var selectors = new List<EndpointSelector>()
+            {
+                selector
+            };
+
+            var selectorContext = new EndpointSelectorContext(httpContext, endpoints, selectors);
+            return (selectorContext, selector);
+        }
+
+        private Task Products_Get(HttpContext httpContext) => httpContext.Response.WriteAsync("Hello, Products_Get");
+
+        private Task Products_Post(HttpContext httpContext) => httpContext.Response.WriteAsync("Hello, Products_Post");
+    }
+}

test/Microsoft.AspNetCore.Dispatcher.Test/Microsoft.AspNetCore.Dispatcher.Test.csproj

@@ -9,4 +9,8 @@
     <ProjectReference Include="..\..\src\Microsoft.AspNetCore.Dispatcher\Microsoft.AspNetCore.Dispatcher.csproj" />
   </ItemGroup>
 
+  <ItemGroup>
+    <PackageReference Include="Microsoft.AspNetCore.Http" />
+  </ItemGroup>
+  
 </Project>