Provide global-wide option to prevent serialization of __type info with JsConfig<T>.ExcludeTypeInfo and specific types with JsConfig<T>.ExcludeTypeInfo.

Ignore __type info for incompatible types, and deserialize based on target type instead.

Author: mythz

NuGet/lib/net35/ServiceStack.Text.dll

@@ -38,8 +38,7 @@ public static ParseStringDelegate GetParseMethod(Type type)
 				var emptyCtorFn = ReflectionExtensions.GetConstructorMethodToCache(type);
 				return value => emptyCtorFn();
 			}
-
-
+			
 			var setterMap = new Dictionary<string, SetPropertyDelegate>();
 			var map = new Dictionary<string, ParseStringDelegate>();
 
@@ -136,7 +135,16 @@ private static object StringToType(Type type, string strType,
 					var typeName = Serializer.ParseString(propertyValueString);
 					instance = ReflectionExtensions.CreateInstance(typeName);
 					if (instance == null)
+					{
 						Tracer.Instance.WriteWarning("Could not find type: " + propertyValueString);
+					}
+					else
+					{
+						//If __type info doesn't match, ignore it.
+						if (!type.IsAssignableFrom(instance.GetType()))
+							instance = null;
+					}
+
 					Serializer.EatItemSeperatorOrMapEndChar(strType, ref index);
 					continue;
 				}
@@ -157,14 +165,14 @@ private static object StringToType(Type type, string strType,
 						{
 							setterFn(instance, propertyValue);
 						}
+
+						Serializer.EatItemSeperatorOrMapEndChar(strType, ref index);
+						continue;
 					}
 					catch (Exception)
 					{
 						Tracer.Instance.WriteWarning("WARN: failed to set dynamic property {0} with: {1}", propertyName, propertyValueString);
 					}
-
-					Serializer.EatItemSeperatorOrMapEndChar(strType, ref index);
-					continue;
 				}
 
 				parseStringFnMap.TryGetValue(propertyName, out parseStringFn);

src/ServiceStack.Text/Common/DeserializeType.cs

@@ -39,11 +39,19 @@ static WriteType()
 
 		public static void TypeInfoWriter(TextWriter writer, object obj)
 		{
-			if (obj == null) return;
+			DidWriteTypeInfo(writer, obj);
+		}
+
+		private static bool DidWriteTypeInfo(TextWriter writer, object obj)
+		{
+			if (obj == null
+			    || JsConfig.ExcludeTypeInfo
+			    || JsConfig<T>.ExcludeTypeInfo) return false;
 
 			Serializer.WriteRawString(writer, JsWriter.TypeAttr);
 			writer.Write(JsWriter.MapKeySeperator);
 			Serializer.WriteRawString(writer, obj.GetType().ToTypeString());
+			return true;
 		}
 
 		public static WriteObjectDelegate Write
@@ -113,16 +121,10 @@ public static void WriteProperties(TextWriter writer, object value)
 			writer.Write(JsWriter.MapStartChar);
 
             var i = 0;
-			if (WriteTypeInfo != null)
+			if (WriteTypeInfo != null || JsState.IsWritingDynamic)
 			{
-				WriteTypeInfo(writer, value);
-			    i++;
+				if (DidWriteTypeInfo(writer, value)) i++;
 			}
-			else if (JsState.IsWritingDynamic)
-			{
-				TypeInfoWriter(writer, value);
-                i++;
-            }
 
 			if (PropertyWriters != null)
 			{

src/ServiceStack.Text/Common/WriteType.cs

@@ -23,6 +23,14 @@ static JsConfig()
 		[ThreadStatic]
 		public static bool IncludeNullValues = false;
 
+		[ThreadStatic]
+		public static bool ExcludeTypeInfo = false;
+
+		public static void Reset()
+		{
+			ConvertObjectTypesIntoStringDictionary =  IncludeNullValues = ExcludeTypeInfo = false;
+		}
+
 #if SILVERLIGHT || MONOTOUCH
 		/// <summary>
 		/// Provide hint to MonoTouch AOT compiler to pre-compile generic classes for all your DTOs.
@@ -172,7 +180,9 @@ public static void RegisterElement<T, TElement>()
 #endif
 
 	public class JsConfig<T> //where T : struct
-	{
+	{	
+		public static bool ExcludeTypeInfo = false;
+
 		/// <summary>
 		/// Define custom serialization fn for BCL Structs
 		/// </summary>

src/ServiceStack.Text/JsConfig.cs

@@ -167,5 +167,26 @@ public void Can_Serialize_User_OAuthSession_list()
 			Assert.That(fromDto.ProviderOAuthAccess[0].Items.Count, Is.EqualTo(2));
 			Assert.That(fromDto.ProviderOAuthAccess[1].Items.Count, Is.EqualTo(2));
 		}
+
+		[Test]
+		public void Doesnt_serialize_TypeInfo_when_set()
+		{
+			JsConfig.ExcludeTypeInfo = true;
+			var userSession = new OAuthUserSession {
+				Id = "1",
+				CreatedAt = DateTime.UtcNow,
+				LastModified = DateTime.UtcNow,
+				ReferrerUrl = "http://referrer.com",
+				ProviderOAuthAccess = new List<IOAuthTokens>
+                {
+                    new OAuthTokens { Provider = "twitter", AccessToken = "TAccessToken", Items = { {"a","1"}, {"b","2"}, }},
+                    new OAuthTokens { Provider = "facebook", AccessToken = "FAccessToken", Items = { {"a","1"}, {"b","2"}, }},
+                }
+			};
+
+			Assert.That(userSession.ToJson().IndexOf("__type") == -1, Is.True);
+			Assert.That(userSession.ToJsv().IndexOf("__type") == -1, Is.True);
+		}
+
 	}
 }

tests/ServiceStack.Text.Tests/InterfaceTests.cs

@@ -1,9 +1,20 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using NUnit.Framework;
 using ServiceStack.Text.Common;
 
 namespace ServiceStack.Text.Tests.JsonTests
 {
+	public interface ICat
+	{
+		string Name { get; set; }
+	}
+
+	public interface IDog
+	{
+		string Name { get; set; }
+	}
+
 	//[KnownType(typeof(Dog))]
 	//[KnownType(typeof(Cat))]
 	public abstract class Animal
@@ -15,7 +26,7 @@ public abstract string Name
 		}
 	}
 
-	public class Dog : Animal
+	public class Dog : Animal, IDog
 	{
 		public override string Name
 		{
@@ -24,7 +35,7 @@ public override string Name
 		}
 	}
 
-	public class Cat : Animal
+	public class Cat : Animal, ICat
 	{
 		public override string Name
 		{
@@ -60,6 +71,13 @@ public string Name
 	[TestFixture]
 	public class PolymorphicListTests : TestBase
 	{
+		[SetUp]
+		public void SetUp()
+		{
+			JsConfig.Reset();
+			JsConfig<ICat>.ExcludeTypeInfo = false;
+		}
+
 		[Test]
 		public void Can_serialise_polymorphic_list()
 		{
@@ -76,7 +94,7 @@ public void Can_serialise_polymorphic_list()
 			Assert.That(asText,
 				Is.EqualTo(
 					"[{\"__type\":\""
-					+ typeof(Dog).ToTypeString() 
+					+ typeof(Dog).ToTypeString()
 					+ "\",\"Name\":\"Fido\"},{\"__type\":\""
 					+ typeof(Cat).ToTypeString()
 					+ "\",\"Name\":\"Tigger\"}]"));
@@ -109,9 +127,9 @@ public void Can_deserialise_polymorphic_list()
 			var list =
 				JsonSerializer.DeserializeFromString<List<Animal>>(
 					"[{\"__type\":\""
-					+ typeof(Dog).ToTypeString() 
+					+ typeof(Dog).ToTypeString()
 					+ "\",\"Name\":\"Fido\"},{\"__type\":\""
-					+ typeof(Cat).ToTypeString() 
+					+ typeof(Cat).ToTypeString()
 					+ "\",\"Name\":\"Tigger\"}]");
 
 			Assert.That(list.Count, Is.EqualTo(2));
@@ -129,9 +147,9 @@ public void Can_deserialise_an_entity_containing_a_polymorphic_list()
 			var zoo =
 				JsonSerializer.DeserializeFromString<Zoo>(
 					"{\"Animals\":[{\"__type\":\""
-					+ typeof(Dog).ToTypeString() 
+					+ typeof(Dog).ToTypeString()
 					+ "\",\"Name\":\"Fido\"},{\"__type\":\""
-					+ typeof(Cat).ToTypeString() 
+					+ typeof(Cat).ToTypeString()
 					+ "\",\"Name\":\"Tigger\"}],\"Name\":\"City Zoo\"}");
 
 			Assert.That(zoo.Name, Is.EqualTo(@"City Zoo"));
@@ -144,5 +162,49 @@ public void Can_deserialise_an_entity_containing_a_polymorphic_list()
 			Assert.That(animals[0].Name, Is.EqualTo(@"Fido"));
 			Assert.That(animals[1].Name, Is.EqualTo(@"Tigger"));
 		}
+
+		public class Pets
+		{
+			public ICat Cat { get; set; }
+			public IDog Dog { get; set; }
+		}
+
+		[Test]
+		public void Can_exclude_specific_TypeInfo()
+		{
+			JsConfig<ICat>.ExcludeTypeInfo = true;
+			var pets = new Pets {
+				Cat = new Cat { Name = "Cat" },
+				Dog = new Dog { Name = "Dog" },
+			};
+
+			Assert.That(pets.ToJson(), Is.EqualTo(
+				@"{""Cat"":{""Name"":""Cat""},""Dog"":{""__type"":""ServiceStack.Text.Tests.JsonTests.Dog, ServiceStack.Text.Tests"",""Name"":""Dog""}}"));
+		}
+
+		public class PetDog
+		{
+			public IDog Dog { get; set; }
+		}
+
+		public class WeirdCat
+		{
+			public Cat Dog { get; set; }
+		}
+
+		[Test]
+		public void Can_read_as_Cat_from_Dog_with_typeinfo()
+		{
+			var petDog = new PetDog { Dog = new Dog { Name = "Woof!" } };
+			var json = petDog.ToJson();
+
+			Console.WriteLine(json);
+
+			var weirdCat = json.FromJson<WeirdCat>();
+
+			Assert.That(weirdCat.Dog, Is.Not.Null);
+			Assert.That(weirdCat.Dog.Name, Is.EqualTo(petDog.Dog.Name));
+		}
+
 	}
 }