Add sample to "select" an address and generate a URL (#434)

Addresses #428

samples/DispatcherSample/DispatcherSample.csproj

@@ -8,6 +8,8 @@
   <ItemGroup>
     <ProjectReference Include="..\..\src\Microsoft.AspNetCore.Dispatcher\Microsoft.AspNetCore.Dispatcher.csproj" />
     <ProjectReference Include="..\..\src\Microsoft.AspNetCore.Dispatcher.Abstractions\Microsoft.AspNetCore.Dispatcher.Abstractions.csproj" />
+    <ProjectReference Include="..\..\src\Microsoft.AspNetCore.Routing.Abstractions\Microsoft.AspNetCore.Routing.Abstractions.csproj" />
+    <ProjectReference Include="..\..\src\Microsoft.AspNetCore.Routing\Microsoft.AspNetCore.Routing.csproj" />
   </ItemGroup>
 
 

samples/DispatcherSample/RouteValueAddress.cs

@@ -0,0 +1,22 @@
+using System;
+// 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.AspNetCore.Dispatcher;
+using Microsoft.AspNetCore.Routing;
+
+namespace DispatcherSample
+{
+    public class RouteValueAddress : Address
+    {
+        public RouteValueAddress(string displayName, RouteValueDictionary dictionary)
+        {
+            DisplayName = displayName;
+            RouteValueDictionary = dictionary;
+        }
+
+        public override string DisplayName { get; }
+
+        public RouteValueDictionary RouteValueDictionary { get; set; }
+    }
+}

samples/DispatcherSample/RouteValueAddressTable.cs

@@ -0,0 +1,28 @@
+// 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 Microsoft.AspNetCore.Routing;
+
+namespace DispatcherSample
+{
+    public class RouteValueAddressTable
+    {
+        public IList<RouteValueAddress> Addresses
+        {
+            get
+            {
+                var addresses = new List<RouteValueAddress>
+                {
+                    new RouteValueAddress("Mickey", new RouteValueDictionary (new { Character = "Mickey" })),
+                    new RouteValueAddress("Hakuna Matata", new RouteValueDictionary (new { Movie = "The Lion King"})),
+                    new RouteValueAddress("Simba", new RouteValueDictionary (new { Movie = "The Lion King", Character = "Simba" })),
+                    new RouteValueAddress("Mufasa", new RouteValueDictionary (new { Movie = "The Lion King", Character = "Mufasa" })),
+                    new RouteValueAddress("Aladdin", new RouteValueDictionary (new { Movie = "Aladdin", Character = "Genie" })),
+                };
+
+                return addresses;
+            }
+        }
+    }
+}

samples/DispatcherSample/Startup.cs

@@ -1,12 +1,12 @@
 // 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;
 using System.Collections.Generic;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Dispatcher;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Routing;
 using Microsoft.Extensions.DependencyInjection;
 
 namespace DispatcherSample
@@ -15,6 +15,8 @@ namespace DispatcherSample
     {
         public void ConfigureServices(IServiceCollection services)
         {
+            services.AddSingleton<UrlGenerator>();
+            services.AddSingleton<RouteValueAddressTable>();
         }
 
         public void Configure(IApplicationBuilder app, IHostingEnvironment env)
@@ -55,9 +57,12 @@ namespace DispatcherSample
             {
                 if (dictionary.TryGetValue(context.Request.Path, out var value))
                 {
-                    var dispatcherFeature = new DispatcherFeature();
-                    dispatcherFeature.Endpoint = value.Endpoint;
-                    dispatcherFeature.RequestDelegate = value.RequestDelegate;
+                    var dispatcherFeature = new DispatcherFeature
+                    {
+                        Endpoint = value.Endpoint,
+                        RequestDelegate = value.RequestDelegate
+                    };
+
                     context.Features.Set<IDispatcherFeature>(dispatcherFeature);
                     await context.Response.WriteAsync("<p>Dispatch</p>");
                     await next.Invoke();
@@ -70,10 +75,18 @@ namespace DispatcherSample
                 await next.Invoke();
             });
 
-            app.Run(async (context) =>
+            app.Use(async (context, next) =>
             {
                 var feature = context.Features.Get<IDispatcherFeature>();
                 await feature.RequestDelegate(context);
+                await next.Invoke();
+            });
+
+            app.Run(async (context) =>
+            {
+                var urlGenerator = app.ApplicationServices.GetService<UrlGenerator>();
+                var url = urlGenerator.GenerateURL(new RouteValueDictionary(new { Movie = "The Lion King", Character = "Mufasa" }), context);
+                await context.Response.WriteAsync($"<p>Generated url: {url}</p>");
             });
         }
     }

samples/DispatcherSample/UrlGenerator.cs

@@ -0,0 +1,58 @@
+// 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.AspNetCore.Http;
+using Microsoft.AspNetCore.Routing;
+
+namespace DispatcherSample
+{
+    public class UrlGenerator
+    {
+        private readonly RouteValueAddressTable _addressTable;
+
+        public UrlGenerator(RouteValueAddressTable addressTable)
+        {
+            _addressTable = addressTable;
+        }
+
+        //Find match from values to a template
+        public string GenerateURL(RouteValueDictionary routeValues, HttpContext context)
+        {
+            var address = FindAddress(_addressTable, routeValues);
+            return $"RouteName: {address.DisplayName} URL: /{address.RouteValueDictionary["Character"]}/{address.RouteValueDictionary["Movie"]}";
+        }
+
+        //Look up the Addresses table
+        private RouteValueAddress FindAddress(RouteValueAddressTable addressTable, RouteValueDictionary routeValues)
+        {
+            var addressMatch = new RouteValueAddress(null, new RouteValueDictionary());
+            foreach (var address in addressTable.Addresses)
+            {
+                foreach (var key in address.RouteValueDictionary.Keys)
+                {
+                    if (!routeValues.Keys.Contains(key))
+                    {
+                        addressMatch.RouteValueDictionary.Clear();
+                        break;
+                    }
+
+                    if (routeValues.Values.Contains(address.RouteValueDictionary[key]))
+                    {
+                        addressMatch.RouteValueDictionary[key] = routeValues[key];
+                    }
+                }
+
+                if (addressMatch.RouteValueDictionary.Count == routeValues.Count)
+                {
+                    return new RouteValueAddress(address.DisplayName, address.RouteValueDictionary);
+                }
+                else
+                {
+                    addressMatch.RouteValueDictionary.Clear();
+                }
+            }
+
+            return addressMatch;
+        }
+    }
+}