Add JsConfig.OnDeserializationError for better introspection of deseriailization errors

Author: mythz

src/ServiceStack.Text/Common/DeserializeTypeRefJson.cs

@@ -160,6 +160,7 @@ internal static object StringToType(
                     }
                     catch (Exception e)
                     {
+                        if (JsConfig.OnDeserializationError != null) JsConfig.OnDeserializationError(instance, propType, propertyName, propertyValueStr, e);
                         if (JsConfig.ThrowOnDeserializationError) throw DeserializeTypeRef.GetSerializationException(propertyName, propertyValueStr, propType, e);
                         else Tracer.Instance.WriteWarning("WARN: failed to set dynamic property {0} with: {1}", propertyName, propertyValueStr);
                     }
@@ -176,6 +177,7 @@ internal static object StringToType(
                     }
                     catch (Exception e)
                     {
+                        if (JsConfig.OnDeserializationError != null) JsConfig.OnDeserializationError(instance, propType, propertyName, propertyValueStr, e);
                         if (JsConfig.ThrowOnDeserializationError) throw DeserializeTypeRef.GetSerializationException(propertyName, propertyValueStr, typeAccessor.PropertyType, e);
                         else Tracer.Instance.WriteWarning("WARN: failed to set property {0} with: {1}", propertyName, propertyValueStr);
                     }

src/ServiceStack.Text/Common/DeserializeTypeRefJsv.cs

@@ -113,6 +113,7 @@ internal static object StringToType(
                     }
                     catch (Exception e)
                     {
+                        if (JsConfig.OnDeserializationError != null) JsConfig.OnDeserializationError(instance, propType, propertyName, propertyValueStr, e);
                         if (JsConfig.ThrowOnDeserializationError) throw DeserializeTypeRef.GetSerializationException(propertyName, propertyValueStr, propType, e);
                         else Tracer.Instance.WriteWarning("WARN: failed to set dynamic property {0} with: {1}", propertyName, propertyValueStr);
                     }
@@ -129,6 +130,7 @@ internal static object StringToType(
                     }
                     catch (Exception e)
                     {
+                        if (JsConfig.OnDeserializationError != null) JsConfig.OnDeserializationError(instance, propType, propertyName, propertyValueStr, e);
                         if (JsConfig.ThrowOnDeserializationError) throw DeserializeTypeRef.GetSerializationException(propertyName, propertyValueStr, propType, e);
                         else Tracer.Instance.WriteWarning("WARN: failed to set property {0} with: {1}", propertyName, propertyValueStr);
                     }

src/ServiceStack.Text/Common/JsDelegates.cs

@@ -33,4 +33,6 @@ namespace ServiceStack.Text.Common
     public delegate object ConvertObjectDelegate(object fromObject);
 
     public delegate object ConvertInstanceDelegate(object obj, Type type);
+
+    public delegate void DeserializationErrorDelegate(object instance, Type propertyType, string propertyName, string propertyValueStr, Exception ex);
 }

src/ServiceStack.Text/JsConfig.cs

@@ -516,6 +516,22 @@ public static bool EscapeUnicode
             }
         }
 
+        /// <summary>
+        /// Gets or sets a value indicating if the framework should call an error handler when
+        /// an exception happens during the deserialization.
+        /// </summary>
+        /// <remarks>Parameters have following meaning in order: deserialized entity, property name, parsed value, property type, caught exception.</remarks>
+        private static DeserializationErrorDelegate sOnDeserializationError;
+        public static DeserializationErrorDelegate OnDeserializationError
+        {
+            get
+            {
+                return (JsConfigScope.Current != null ? JsConfigScope.Current.OnDeserializationError : null)
+                    ?? sOnDeserializationError;
+            }
+            set { sOnDeserializationError = value; }
+        }
+
         internal static HashSet<Type> HasSerializeFn = new HashSet<Type>();
 
         internal static HashSet<Type> HasIncludeDefaultValue = new HashSet<Type>();
@@ -691,6 +707,7 @@ public static void Reset()
             sAssumeUtc = null;
             sAppendUtcOffset = null;
             sEscapeUnicode = null;
+            sOnDeserializationError = null;
             sIncludePublicFields = null;
             sReuseStringBuffer = null;
             HasSerializeFn = new HashSet<Type>();

src/ServiceStack.Text/JsConfigScope.cs

@@ -4,6 +4,7 @@
 using System.Text;
 using System.Threading;
 using System.Diagnostics;
+using ServiceStack.Text.Common;
 
 namespace ServiceStack.Text
 {
@@ -81,6 +82,7 @@ public void Dispose()
         public bool? IncludePublicFields { get; set; }
         public bool? ReuseStringBuffer { get; set; }
         public int? MaxDepth { get; set; }
+        public DeserializationErrorDelegate OnDeserializationError { get; set; }
         public EmptyCtorFactoryDelegate ModelFactory { get; set; }
         public string[] ExcludePropertyReferences { get; set; }
         public HashSet<Type> ExcludeTypes { get; set; }