Allow custom formatting of Links in JSON.NET

VERSION.txt

@@ -1 +1 @@
-BUILD_VERSION = "0.10.4"
+BUILD_VERSION = "0.11.1"

packaging/nuspec/Simple.Web.AspNet.nuspec

@@ -14,7 +14,7 @@
     <tags>simple.web</tags>
     <dependencies>
       <dependency id="Simple.Web" version="0.0.0.0" />
-      <dependency id="Fix.AspNet" version="0.4" />
+      <dependency id="Fix.AspNet" version="0.6" />
     </dependencies>
   </metadata>
   <files>

src/Simple.Web.JsonNet.Tests/Simple.Web.JsonNet.Tests.csproj

@@ -62,6 +62,7 @@
       <Link>Properties\CommonAssemblyInfo.cs</Link>
     </Compile>
     <Compile Include="HalJsonMediaTypeHandlerTests.cs" />
+    <Compile Include="SimpleLinkFormatterTests.cs" />
   </ItemGroup>
   <ItemGroup>
     <None Include="packages.config" />

src/Simple.Web.JsonNet.Tests/SimpleLinkFormatterTests.cs

@@ -0,0 +1,65 @@
+namespace Simple.Web.JsonNet.Tests
+{
+    using System;
+    using System.Collections.Generic;
+    using MediaTypeHandling;
+    using Newtonsoft.Json.Linq;
+    using TestHelpers;
+    using TestHelpers.Sample;
+    using Xunit;
+
+    public class SimpleLinkFormatterTests
+    {
+        [Fact]
+        public void PicksUpOrdersLinkFromCustomer()
+        {
+            const string idProperty = @"""id"":42";
+            const string ordersLink =
+                @"{""title"":null,""href"":""/customer/42/orders"",""rel"":""customer.orders"",""type"":""application/vnd.list.order+json""}";
+            const string selfLink =
+                @"{""title"":null,""href"":""/customer/42"",""rel"":""self"",""type"":""application/vnd.customer+json""}";
+
+            var content = new Content(new Uri("http://test.com/customer/42"), new CustomerHandler(),
+                new Customer {Id = 42});
+            var target = new JsonMediaTypeHandler
+            {
+                JsonLinksFormatter = new SimpleJsonLinksFormatter()
+            };
+            string json;
+            using (var stream = new StringBuilderStream())
+            {
+                target.Write<Customer>(content, stream).Wait();
+                json = stream.StringValue;
+            }
+            var jobj = JObject.Parse(json);
+            var links = jobj["_links"] as JObject;
+            Assert.NotNull(links);
+            Assert.Equal(links["customer.orders"].ToString(), "/customer/42/orders");
+            Assert.Equal(links["self"].ToString(), "/customer/42");
+        }
+
+        [Fact]
+        public void PicksUpPathFromThing()
+        {
+            const string thingLink =
+                @"{""title"":null,""href"":""/things?path=%2Ffoo%2Fbar"",""rel"":""self"",""type"":""application/json""}";
+
+            var content = new Content(new Uri("http://test.com/foo/bar"), new ThingHandler(),
+                new Thing {Path = "/foo/bar"});
+            var target = new JsonMediaTypeHandler
+            {
+                JsonLinksFormatter = new SimpleJsonLinksFormatter()
+            };
+            string json;
+            using (var stream = new StringBuilderStream())
+            {
+                target.Write<Thing>(content, stream).Wait();
+                json = stream.StringValue;
+            }
+            var jobj = JObject.Parse(json);
+            var links = jobj["_links"] as JObject;
+            Assert.NotNull(links);
+            Assert.Equal(links["self"].ToString(), "/things?path=%2Ffoo%2Fbar");
+        }
+    }
+}

src/Simple.Web.JsonNet/DefaultJsonLinksFormatter.cs

@@ -0,0 +1,28 @@
+namespace Simple.Web.JsonNet
+{
+    using System.Collections.Generic;
+    using Links;
+    using Newtonsoft.Json;
+    using Newtonsoft.Json.Linq;
+
+    public class DefaultJsonLinksFormatter : IJsonLinksFormatter
+    {
+        private string _linksPropertyName = "links";
+
+        public string LinksPropertyName
+        {
+            get { return _linksPropertyName; }
+            set { _linksPropertyName = value; }
+        }
+
+        public void FormatLinks(JContainer container, IEnumerable<Link> links, JsonSerializer serializer)
+        {
+            var jLinks = new JArray();
+            foreach (var link in links)
+            {
+                jLinks.Add(JObject.FromObject(link, serializer));
+            }
+            container[_linksPropertyName] = jLinks;
+        }
+    }
+}

src/Simple.Web.JsonNet/IJsonLinksFormatter.cs

@@ -0,0 +1,26 @@
+namespace Simple.Web.JsonNet
+{
+    using System.Collections.Generic;
+    using Links;
+    using Newtonsoft.Json;
+    using Newtonsoft.Json.Linq;
+
+    /// <summary>
+    /// Interface for types that format <see cref="Link"/> collections for JSON.NET
+    /// </summary>
+    /// <remarks>
+    /// The implementing types do not write the actual JSON text, rather, they create a JSON.NET <see cref="JToken"/>
+    /// allowing them to specify the structure or layout of the object.
+    /// </remarks>
+    public interface IJsonLinksFormatter
+    {
+        /// <summary>
+        /// Formats the links for a JSON item.
+        /// </summary>
+        /// <param name="container">The object to which the links will be added</param>
+        /// <param name="links">The links. Guaranteed to be non-empty.</param>
+        /// <param name="serializer">The serializer.</param>
+        /// <returns></returns>
+        void FormatLinks(JContainer container, IEnumerable<Link> links, JsonSerializer serializer);
+    }
+}

src/Simple.Web.JsonNet/JsonMediaTypeHandler.cs

@@ -11,6 +11,22 @@ namespace Simple.Web.JsonNet
     [MediaTypes(MediaType.Json, "application/*+json")]
     public class JsonMediaTypeHandler : JsonNetMediaTypeHandlerBase
     {
+        private static IJsonLinksFormatter _defaultJsonLinksFormatter = new DefaultJsonLinksFormatter();
+
+        public static IJsonLinksFormatter DefaultJsonLinksFormatter
+        {
+            get { return _defaultJsonLinksFormatter; }
+            set { _defaultJsonLinksFormatter = value; }
+        }
+
+        private IJsonLinksFormatter _jsonLinksFormatter = _defaultJsonLinksFormatter;
+
+        public IJsonLinksFormatter JsonLinksFormatter
+        {
+            get { return _jsonLinksFormatter; }
+            set { _jsonLinksFormatter = value; }
+        }
+
         static JsonMediaTypeHandler()
         {
             SetDefaultSettings(new JsonSerializerSettings
@@ -23,18 +39,12 @@ static JsonMediaTypeHandler()
 
         protected override void AddWireFormattedLinks(JToken wireFormattedItem, IEnumerable<Link> itemLinks)
         {
-            IList<Link> links = itemLinks as IList<Link> ?? itemLinks.ToList();
+            var links = itemLinks as IList<Link> ?? itemLinks.ToList();
             if (links.Count == 0)
             {
                 return;
             }
-            var jLinks = new JArray();
-            foreach (Link link in links)
-            {
-                EnsureLinkTypeIsJson(link);
-                jLinks.Add(JObject.FromObject(link, Serializer));
-            }
-            wireFormattedItem["links"] = jLinks;
+            _jsonLinksFormatter.FormatLinks((JContainer)wireFormattedItem, links.Where(EnsureLinkTypeIsJson), Serializer);
         }
 
         protected override JToken WrapCollection(IList<JToken> collection, IEnumerable<Link> collectionLinks)

src/Simple.Web.JsonNet/JsonNetMediaTypeHandlerBase.cs

@@ -28,7 +28,7 @@ protected JsonSerializer Serializer
             get { return _serializer ?? (_serializer = JsonSerializer.Create(Settings)); }
         }
 
-        protected void EnsureLinkTypeIsJson(Link link)
+        protected bool EnsureLinkTypeIsJson(Link link)
         {
             if (String.IsNullOrWhiteSpace(link.Type))
             {
@@ -37,7 +37,8 @@ protected void EnsureLinkTypeIsJson(Link link)
             if (!link.Type.EndsWith("json"))
             {
                 link.Type += "+json";
-            }
+            }
+            return true;
         }
 
         protected override Task<T> FromWireFormat<T>(JToken wireFormat)

src/Simple.Web.JsonNet/Simple.Web.JsonNet.csproj

@@ -45,6 +45,8 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="DefaultJsonLinksFormatter.cs" />
+    <Compile Include="IJsonLinksFormatter.cs" />
     <Compile Include="JsonMediaTypeHandlerWithDeepLinks.cs" />
     <Compile Include="JsonNetMediaTypeHandlerBase.cs" />
     <Compile Include="LinkConverter.cs" />
@@ -54,6 +56,7 @@
     </Compile>
     <Compile Include="HalJsonMediaTypeHandler.cs" />
     <Compile Include="JsonMediaTypeHandler.cs" />
+    <Compile Include="SimpleJsonLinksFormatter.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\Simple.Web\Simple.Web.csproj">

src/Simple.Web.JsonNet/SimpleJsonLinksFormatter.cs

@@ -0,0 +1,36 @@
+namespace Simple.Web.JsonNet
+{
+    using System.Collections.Generic;
+    using Links;
+    using Newtonsoft.Json;
+    using Newtonsoft.Json.Linq;
+
+    /// <summary>
+    /// Formats links in JSON using a light-weight object format.
+    /// </summary>
+    /// <example>
+    /// A customer object might be formatted like this:
+    /// 
+    /// {"name":"ACME","_links":{"self":"/customers/acme","orders":"customers/acme/orders"}}
+    /// </example>
+    public class SimpleJsonLinksFormatter : IJsonLinksFormatter
+    {
+        private string _linksPropertyName = "_links";
+
+        public string LinksPropertyName
+        {
+            get { return _linksPropertyName; }
+            set { _linksPropertyName = value; }
+        }
+
+        public void FormatLinks(JContainer container, IEnumerable<Link> links, JsonSerializer serializer)
+        {
+            var jLinks = new JObject();
+            foreach (var link in links)
+            {
+                jLinks[link.Rel] = JValue.CreateString(link.Href);
+            }
+            container[_linksPropertyName] = jLinks;
+        }
+    }
+}

src/Simple.Web.Tests/ApplicationTests/ContentTypeTests.cs

@@ -7,82 +7,82 @@ public class ContentTypeTests
         [Fact]
         public void FileWithASingleAcceptTypeReturnsThatType()
         {
-            var type = Application.GetContentType("any", new[] { "test/type" });
+            var type = StaticContent.GetContentType("any", new[] { "test/type" });
 
             Assert.Equal("test/type", type);
         }
 
         [Fact]
         public void FileWithMultipleAcceptTypeReturnsFirstType()
         {
-            var type = Application.GetContentType("any", new[] { "type/one", "type/two", "*/*" });
+            var type = StaticContent.GetContentType("any", new[] { "type/one", "type/two", "*/*" });
 
             Assert.Equal("type/one", type);
         }
 
         [Fact]
         public void FileWithNullAcceptTypesReturnsPlainText()
         {
-            var type = Application.GetContentType("any", null);
+            var type = StaticContent.GetContentType("any", null);
 
             Assert.Equal("text/plain", type);
         }
 
         [Fact]
         public void FileWithEmptyAcceptTypesReturnsPlainText()
         {
-            var type = Application.GetContentType("any", new string[] { });
+            var type = StaticContent.GetContentType("any", new string[] { });
 
             Assert.Equal("text/plain", type);
         }
 
         [Fact]
         public void FileWithWildcardAcceptTypeAndNoKnownExtensionReturnsPlainText()
         {
-            var type = Application.GetContentType("any", new[] { "*/*" });
+            var type = StaticContent.GetContentType("any", new[] { "*/*" });
 
             Assert.Equal("text/plain", type);
         }
 
         [Fact]
         public void FileWithWildcardAcceptType_Jpg_ExtensionReturns_Jpeg()
         {
-            var type = Application.GetContentType("any.jpg", new[] { "*/*" });
+            var type = StaticContent.GetContentType("any.jpg", new[] { "*/*" });
 
             Assert.Equal("image/jpeg", type);
         }
         [Fact]
         public void FileWithWildcardAcceptType_Jpeg_ExtensionReturns_Jpeg()
         {
-            var type = Application.GetContentType("any.jpeg", new[] { "*/*" });
+            var type = StaticContent.GetContentType("any.jpeg", new[] { "*/*" });
 
             Assert.Equal("image/jpeg", type);
         }
         [Fact]
         public void FileWithWildcardAcceptType_Png_ExtensionReturns_Png()
         {
-            var type = Application.GetContentType("any.png", new[] { "*/*" });
+            var type = StaticContent.GetContentType("any.png", new[] { "*/*" });
 
             Assert.Equal("image/png", type);
         }
         [Fact]
         public void FileWithWildcardAcceptType_Gif_ExtensionReturns_gif()
         {
-            var type = Application.GetContentType("any.gif", new[] { "*/*" });
+            var type = StaticContent.GetContentType("any.gif", new[] { "*/*" });
 
             Assert.Equal("image/gif", type);
         }
         [Fact]
         public void FileWithWildcardAcceptType_Js_ExtensionReturns_JavaScript()
         {
-            var type = Application.GetContentType("any.js", new[] { "*/*" });
+            var type = StaticContent.GetContentType("any.js", new[] { "*/*" });
 
             Assert.Equal("text/javascript", type);
         }
         [Fact]
         public void FileWithWildcardAcceptType_Javascript_ExtensionReturns_JavaScript()
         {
-            var type = Application.GetContentType("any.JavaScript", new[] { "*/*" });
+            var type = StaticContent.GetContentType("any.JavaScript", new[] { "*/*" });
 
             Assert.Equal("text/javascript", type);
         }