Serialize recursively placing all nested objects in the 'included' array

Saule/Serialization/ResourceSerializer.cs

@@ -49,7 +49,7 @@ public JObject Serialize(JsonSerializer serializer)
 
             var result = new JObject
             {
-                ["data"] = SerializeArrayOrObject(objectJson, SerializeData),
+                ["data"] = SerializeArrayOrObject(_resource, objectJson, SerializeData),
                 ["links"] = new JObject
                 {
                     ["self"] = new JValue(_baseUrl)
@@ -66,21 +66,21 @@ public JObject Serialize(JsonSerializer serializer)
             return result;
         }
 
-        private static JToken SerializeArrayOrObject(JToken token, Func<IDictionary<string, JToken>, JToken> serializeObj)
+        private static JToken SerializeArrayOrObject(ApiResource resource, JToken token, Func<ApiResource, IDictionary<string, JToken>, JToken> serializeObj)
         {
             var dataArray = token as JArray;
 
             // single thing, just serialize it
             if (dataArray == null)
             {
-                return token is JObject ? serializeObj((JObject)token) : null;
+                return token is JObject ? serializeObj(resource, (JObject)token) : null;
             }
 
             // serialize each element separately
             var data = new JArray();
             foreach (var obj in dataArray.OfType<JObject>())
             {
-                data.Add(serializeObj(obj));
+                data.Add(serializeObj(resource, obj));
             }
 
             return data;
@@ -171,12 +171,12 @@ private JToken CreateTopLevelLinks(int count)
             return result;
         }
 
-        private JToken SerializeData(IDictionary<string, JToken> properties)
+        private JToken SerializeData(ApiResource resource, IDictionary<string, JToken> properties)
         {
             var data = SerializeMinimalData(properties);
 
             data["attributes"] = SerializeAttributes(properties);
-            data["relationships"] = SerializeRelationships(properties);
+            data["relationships"] = SerializeRelationships(resource, properties);
 
             if (_isCollection)
             {
@@ -199,11 +199,11 @@ private JToken SerializeAttributes(IDictionary<string, JToken> properties)
             return SerializeAttributes(properties, _resource);
         }
 
-        private JToken SerializeRelationships(IDictionary<string, JToken> properties)
+        private JToken SerializeRelationships(ApiResource resource, IDictionary<string, JToken> properties)
         {
             var relationships = new JObject();
 
-            foreach (var rel in _resource.Relationships)
+            foreach (var rel in resource.Relationships)
             {
                 relationships[rel.Name] = SerializeRelationship(rel, properties);
             }
@@ -240,8 +240,9 @@ private JToken SerializeRelationship(ResourceRelationship relationship, IDiction
         private JToken GetRelationshipData(ResourceRelationship relationship, JToken relationshipValues)
         {
             var data = SerializeArrayOrObject(
+                relationship.RelatedResource,
                 relationshipValues,
-                props =>
+                (resource, props) =>
                 {
                     var values = SerializeMinimalData(props, relationship.RelatedResource);
                     var includedData = values.DeepClone();
@@ -250,6 +251,7 @@ private JToken GetRelationshipData(ResourceRelationship relationship, JToken rel
                         (string)EnsureHasId(props, relationship.RelatedResource));
 
                     includedData["attributes"] = SerializeAttributes(props, relationship.RelatedResource);
+                    includedData["relationships"] = SerializeRelationships(resource, props);
                     includedData["links"] = AddUrl(new JObject(), "self", url);
                     if (!IsResourceIncluded(includedData))
                     {

Tests/Models/Recursion.cs

@@ -4,32 +4,64 @@ namespace Tests.Models
 {
     internal static class Recursion
     {
-        public class Resource : ApiResource
+        public class FirstModelResource : ApiResource
         {
-            public Resource()
+            public FirstModelResource()
             {
-                BelongsTo<Second>("Model");
+                BelongsTo<SecondModelResource>("Child");
             }
+        }
+
+        public class SecondModelResource : ApiResource
+        {
+            public SecondModelResource()
+            {
+                BelongsTo<FirstModelResource>("Parent");
+                BelongsTo<ThirdModelResource>("Child");
+            }
+        }
+
+        public class ThirdModelResource : ApiResource
+        {
+            public ThirdModelResource()
+            {
+                BelongsTo<SecondModelResource>("Parent");
+                BelongsTo<FourthModelResource>("Child");
+            }
+        }
 
-            private class Second : ApiResource
+        public class FourthModelResource : ApiResource
+        {
+            public FourthModelResource()
             {
-                public Second()
-                {
-                    BelongsTo<Resource>("Model");
-                }
+                BelongsTo<ThirdModelResource>("Parent");
             }
         }
 
         public class FirstModel
         {
-            public string Id => "123";
-            public SecondModel Model { get; set; }
+            public string Id = "1";
+            public SecondModel Child { get; set; }
         }
 
         public class SecondModel
         {
-            public string Id => "456";
-            public FirstModel Model { get; set; }
+            public string Id = "2";
+            public FirstModel Parent { get; set; }
+            public ThirdModel Child { get; set; }
+        }
+
+        public class ThirdModel
+        {
+            public string Id = "3";
+            public SecondModel Parent { get; set; }
+            public FourthModel Child { get; set; }
+        }
+
+        public class FourthModel
+        {
+            public string Id = "4";
+            public ThirdModel Parent { get; set; }
         }
     }
 }

Tests/Serialization/ResourceSerializerTests.cs

@@ -31,18 +31,25 @@ public void HandlesRecursiveProperties()
         {
             var firstModel = new Recursion.FirstModel();
             var secondModel = new Recursion.SecondModel();
-            firstModel.Model = secondModel;
-            secondModel.Model = firstModel;
-
-            var target = new ResourceSerializer(firstModel, new Recursion.Resource(), 
-                GetUri(id: "123"), DefaultPathBuilder, null);
+            var thirdModel = new Recursion.ThirdModel();
+            var fourthModel = new Recursion.FourthModel();
+            firstModel.Child = secondModel;
+            secondModel.Parent = firstModel;
+            secondModel.Child = thirdModel;
+            thirdModel.Parent = secondModel;
+            thirdModel.Child = fourthModel;
+            fourthModel.Parent = thirdModel;
+
+            var target = new ResourceSerializer(firstModel, new Recursion.FirstModelResource(), 
+                GetUri(id: firstModel.Id), DefaultPathBuilder, null);
 
             var result = target.Serialize();
             _output.WriteLine(result.ToString());
 
             var id = result["data"].Value<string>("id");
 
             Assert.Equal(firstModel.Id, id);
+            Assert.Equal(3, (result["included"] as JArray).Count);
         }
 
         [Fact(DisplayName = "Uses a property called 'Id' when none is specified for Ids")]