Fix stack overflow error when serializing complex object graph

src/ServiceStack.Text/Common/SerializationVisitorTracker.cs

@@ -0,0 +1,47 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+
+namespace ServiceStack.Text.Common
+{
+    internal static class SerializationVisitorTracker
+    {
+        static Dictionary<TextWriter, List<object>> VisitedCache = new Dictionary<TextWriter, List<object>>();
+
+        internal static void TrackSerialization(TextWriter writer)
+        {
+            lock (VisitedCache)
+            {
+                VisitedCache.Add(writer, new List<object>());
+            }
+        }
+
+        internal static void UnTrackSerialization(TextWriter writer)
+        {
+            lock (VisitedCache)
+            {
+                VisitedCache.Remove(writer);
+            }
+        }
+
+        internal static bool HasVisited(TextWriter writer, object o)
+        {
+            lock (VisitedCache)
+            {
+                return VisitedCache[writer].Exists(x => Object.ReferenceEquals(x, o));
+            }
+        }
+
+        internal static void Track(TextWriter writer, object o)
+        {
+            lock (VisitedCache)
+            {
+                VisitedCache[writer].Add(o);
+            }
+        }
+    }
+
+
+}

src/ServiceStack.Text/Common/WriteType.cs

@@ -16,6 +16,7 @@
 using System.Reflection;
 using ServiceStack.Text.Json;
 using ServiceStack.Text.Reflection;
+using System.Collections.Generic;
 
 namespace ServiceStack.Text.Common
 {
@@ -281,9 +282,11 @@ public static void WriteProperties(TextWriter writer, object value)
                         ? propertyWriter.GetterFn((T)value)
                         : null;
 
-                    if ((propertyValue == null
-                         || (propertyWriter.DefaultValue != null && propertyWriter.DefaultValue.Equals(propertyValue)))
-                        && !Serializer.IncludeNullValues) continue;
+                    if ( ((propertyValue == null
+                          || (propertyWriter.DefaultValue != null && propertyWriter.DefaultValue.Equals(propertyValue)))
+                          && !Serializer.IncludeNullValues)
+                         || (propertyValue != null && SerializationVisitorTracker.HasVisited(writer,propertyValue)) )
+                        continue;
 
                     if (i++ > 0)
                         writer.Write(JsWriter.ItemSeperator);
@@ -298,6 +301,7 @@ public static void WriteProperties(TextWriter writer, object value)
                     }
                     else
                     {
+                        SerializationVisitorTracker.Track(writer, propertyValue);
                         propertyWriter.WriteFn(writer, propertyValue);
                     }
                     if (typeof(TSerializer) == typeof(JsonTypeSerializer)) JsState.IsWritingValue = false;

src/ServiceStack.Text/ServiceStack.Text.csproj

@@ -139,6 +139,7 @@
     <Compile Include="Common\StaticParseMethod.cs">
       <SubType>Code</SubType>
     </Compile>
+    <Compile Include="Common\SerializationVisitorTracker.cs" />
     <Compile Include="Common\WriteDictionary.cs">
       <SubType>Code</SubType>
     </Compile>

src/ServiceStack.Text/TypeSerializer.cs

@@ -91,7 +91,15 @@ public static string SerializeToString<T>(T value)
 			var sb = new StringBuilder();
 			using (var writer = new StringWriter(sb, CultureInfo.InvariantCulture))
 			{
-				JsvWriter<T>.WriteObject(writer, value);
+                try
+                {
+                    SerializationVisitorTracker.TrackSerialization(writer);
+                    JsvWriter<T>.WriteObject(writer, value);
+                }
+                finally
+                {
+                    SerializationVisitorTracker.UnTrackSerialization(writer);
+                }
 			}
 			return sb.ToString();
 		}
@@ -104,7 +112,15 @@ public static string SerializeToString(object value, Type type)
 			var sb = new StringBuilder();
 			using (var writer = new StringWriter(sb, CultureInfo.InvariantCulture))
 			{
-				JsvWriter.GetWriteFn(type)(writer, value);
+                try
+                {
+                    SerializationVisitorTracker.TrackSerialization(writer);
+                    JsvWriter.GetWriteFn(type)(writer, value);
+                }
+                finally
+                {
+                    SerializationVisitorTracker.UnTrackSerialization(writer);
+                }
 			}
 			return sb.ToString();
 		}
@@ -125,8 +141,16 @@ public static void SerializeToWriter<T>(T value, TextWriter writer)
                 return;
 			}
 
-			JsvWriter<T>.WriteObject(writer, value);
-		}
+            try
+            {
+                SerializationVisitorTracker.TrackSerialization(writer);
+                JsvWriter<T>.WriteObject(writer, value);
+            }
+            finally
+            {
+                SerializationVisitorTracker.UnTrackSerialization(writer);
+            }
+        }
 
 		public static void SerializeToWriter(object value, Type type, TextWriter writer)
 		{
@@ -137,7 +161,15 @@ public static void SerializeToWriter(object value, Type type, TextWriter writer)
 				return;
 			}
 
-			JsvWriter.GetWriteFn(type)(writer, value);
+            try
+            {
+                SerializationVisitorTracker.TrackSerialization(writer);
+                JsvWriter.GetWriteFn(type)(writer, value);
+            }
+            finally
+            {
+                SerializationVisitorTracker.UnTrackSerialization(writer);
+            }
 		}
 
 		public static void SerializeToStream<T>(T value, Stream stream)
@@ -152,15 +184,31 @@ public static void SerializeToStream<T>(T value, Stream stream)
 			}
 
 			var writer = new StreamWriter(stream, UTF8EncodingWithoutBom);
-			JsvWriter<T>.WriteObject(writer, value);
-			writer.Flush();
+            try
+            {
+                SerializationVisitorTracker.TrackSerialization(writer);
+                JsvWriter<T>.WriteObject(writer, value);
+            }
+            finally
+            {
+                SerializationVisitorTracker.UnTrackSerialization(writer);
+            }
+            writer.Flush();
 		}
 
 		public static void SerializeToStream(object value, Type type, Stream stream)
 		{
 			var writer = new StreamWriter(stream, UTF8EncodingWithoutBom);
-			JsvWriter.GetWriteFn(type)(writer, value);
-			writer.Flush();
+            try
+            {
+                SerializationVisitorTracker.TrackSerialization(writer);
+    			JsvWriter.GetWriteFn(type)(writer, value);
+            }
+            finally
+            {
+                SerializationVisitorTracker.UnTrackSerialization(writer);
+            }
+            writer.Flush();
 		}
 
 		public static T Clone<T>(T value)