protected virtual Expression GetExpression(IEnumerable Items, Type ItemType, JsonPath CurrentPath, ISerializerHandler serializer)
{
int index = 0;
ArrayExpression expression = new ArrayExpression();
foreach (object value in Items)
{
Expression itemExpr = serializer.Serialize(value, CurrentPath.Append(index));
if (value != null && !ReflectionUtils.AreEquivalentTypes(value.GetType(), ItemType))
{
itemExpr = new CastExpression(value.GetType(), itemExpr);
}
expression.Add(itemExpr);
index++;
}
return expression;
}
public Expression HandleReference(object value, JsonPath CurrentPath)
{
if (!IsReferenceable(value))
return null;
ReferenceInfo refInfo = null;
if (_refs.ContainsKey(value))
{
/*
* This object has already been seen by the serializer so
* determine what to do with it. If its part of the current path
* then its a circular reference and an error needs to be thrown or it should
* be ignored depending on the option. Otherwise write a reference to it
*/
refInfo = _refs[value];
JsonPath refPath = refInfo.Path;
switch (_context.ReferenceWritingType)
{
case SerializationContext.ReferenceOption.WriteIdentifier:
if (!refInfo.CanReference)
throw new InvalidOperationException("Can't reference object: " + refPath + " from " + CurrentPath + ", either it is a collection, or it has not been converted yet");
return new ReferenceExpression(refPath);
case SerializationContext.ReferenceOption.IgnoreCircularReferences:
if (CurrentPath.StartsWith(refPath))
{
return new NullExpression();
}
break;
case SerializationContext.ReferenceOption.ErrorCircularReferences:
if (CurrentPath.StartsWith(refPath))
{
throw new InvalidOperationException("Circular reference detected. Current path: " + CurrentPath + ", reference to: " + refPath);
}
break;
}
}
else
{
refInfo = new ReferenceInfo(CurrentPath);
_refs[value] = refInfo;
}
return null;
}
public void VisitComplexBase(ComplexExpressionBase expression)
{
if (_refID.Top == JsonPath.Root)
{
if (expression.Parent != null)
{
throw new ArgumentException("Reference for this passed to object that is not at the root", "refID");
}
}
else
{
// have to assume that the parent checked that we were the right reference
// should only get here if we have a parent, if no parent we're not valid
if (expression.Parent == null)
throw new ArgumentException("Invalid reference", "refID");
}
// it is this object, check if we need to go further
_refID = _refID.ChildReference();
if (_refID.IsEmpty) {
_expr = expression;
}
}
/// <summary>
/// Gets an expression for a value by first converting it with its registered type converter and then calling Serialize
/// </summary>
/// <param name="value">the value to generate an expression for</param>
/// <param name="currentPath">the current path to the value</param>
/// <param name="serializer">serializer instance</param>
/// <returns>an expression for the value</returns>
public override Expression GetExpression(object value, JsonPath currentPath, ISerializerHandler serializer)
{
TypeData handler = Context.TypeHandlerFactory[value.GetType()];
IJsonTypeConverter converter = (handler.HasConverter ? handler.TypeConverter : (IJsonTypeConverter)value);
return GetExpression(value, converter, currentPath, serializer);
}
/// <summary>
/// Serializes the data into a json array expression.
/// </summary>
/// <param name="data">the data to serialize</param>
/// <param name="currentPath">the current path to the data</param>
/// <param name="serializer">serializer instance to use to serialize list items</param>
/// <returns>a json array expression representation</returns>
public override Expression GetExpression(object data, JsonPath currentPath, ISerializerHandler serializer)
{
TypeData handler = Context.GetTypeHandler(data.GetType());
CollectionHandler collectionHandler = handler.GetCollectionHandler();
Type elemType = collectionHandler.GetItemType(handler.ForType);
int index = 0;
ArrayExpression expression = new ArrayExpression();
foreach (object value in collectionHandler.GetEnumerable(data))
{
Expression itemExpr = serializer.Serialize(value, currentPath.Append(index));
if (value != null && !ReflectionUtils.AreEquivalentTypes(value.GetType(), elemType))
{
itemExpr = new CastExpression(value.GetType(), itemExpr);
}
expression.Add(itemExpr);
index++;
}
return expression;
}
public bool StartsWith(JsonPath value)
{
return(this.ToString().StartsWith(value.ToString()));
}
/// <summary>
/// Parses a reference to an object
/// </summary>
/// <returns></returns>
private Expression ParseReference()
{
JsonPath refID = new JsonPath();
Token tok = ReadToken();
if (tok != ReferenceStartToken && tok != OldReferenceStartToken)
throw new ParseException(string.Format("Invalid starting token for ParseReference, Expected: {0} or {1}, got: {2}", ReferenceStartToken, OldReferenceStartToken,tok));
while (PeekToken() == PeriodToken || PeekToken() == LSquareToken)
{
tok = ReadToken(); // separator "."
if (tok == PeriodToken)
tok = ReadToken(); // type part
if (tok == LSquareToken)
{
refID = refID.Append(ReadToken().value); // index
ReadToken(); // ]
}
else if (tok.type == TokenType.Identifier)
{
refID = refID.Append(tok.value);
}
else
{
throw new ParseException("Invalid Reference, must be an identifier or array value: " + tok);
}
}
return new ReferenceExpression(refID);
}
public override Expression GetExpression(object data, JsonPath CurrentPath, ISerializerHandler serializer)
{
return GetExpression((IEnumerable)data, GetItemType(data.GetType()), CurrentPath, serializer);
}
public ReferenceVisitor(JsonPath RefID)
{
_refID = RefID;
}
public bool StartsWith(JsonPath value)
{
return this.ToString().StartsWith(value.ToString());
}
/// <summary>
/// Serialize the given object at the current indent level. The path to the object is represented by
/// currentPath such as "this.name", etc. This is an internal method that can be called recursively.
/// </summary>
/// <param name="value">the object to serialize</param>
/// <param name="currentPath">the current path for reference writing</param>
public Expression Serialize(object value, JsonPath currentPath, IJsonTypeConverter converter)
{
if (value == null)
{
return new NullExpression();
}
else
{
Expression expr = HandleReference(value, currentPath);
if (expr != null)
return expr;
ISerializationCallback callback = value as ISerializationCallback;
if (callback != null)
callback.OnBeforeSerialization();
try
{
//TODO: this is too early for converters
SetCanReference(value); // regular object, can reference at any time
IExpressionHandler objHandler;
if (converter != null)
{
TypeConverterExpressionHandler converterHandler = (TypeConverterExpressionHandler)_context.ExpressionHandlers.Find(typeof(TypeConverterExpressionHandler));
//TODO: make sure it exists
return converterHandler.GetExpression(value, converter, currentPath, this);
}
objHandler = _context.ExpressionHandlers.GetHandler(value);
return objHandler.GetExpression(value, currentPath, this);
}
finally
{
if (callback != null)
callback.OnAfterSerialization();
}
}
}
public override Expression GetExpression(object data, JsonPath currentPath, ISerializerHandler serializer)
{
string value = ((DateTime)data).ToString(dateFormat, Culture);
return new ValueExpression(value);
}
/// <summary>
/// Serialize an object implementing IDictionary. The serialized data is similar to a regular
/// object, except that the keys of the dictionary are used instead of properties.
/// </summary>
/// <param name="data">the dictionary object</param>
/// <param name="currentPath">object's path</param>
/// <param name="serializer">the serializer instance, used to serialize keys and values</param>
public override Expression GetExpression(object data, JsonPath currentPath, ISerializerHandler serializer)
{
IDictionary dictionary = (IDictionary)data;
Type itemType = typeof(object);
Type genericDictionary = null;
if ((genericDictionary = dictionary.GetType().GetInterface(typeof(IDictionary<,>).Name)) != null)
{
itemType = genericDictionary.GetGenericArguments()[1];
}
ObjectExpression expression = new ObjectExpression();
foreach (DictionaryEntry pair in dictionary)
{
//may not work in all cases
object value = pair.Value;
Expression valueExpr = serializer.Serialize(value, currentPath.Append(pair.Key.ToString()));
if (value != null && !ReflectionUtils.AreEquivalentTypes(value.GetType(), itemType))
{
valueExpr = new CastExpression(value.GetType(), valueExpr);
}
expression.Add(pair.Key.ToString(), valueExpr);
}
return expression;
}
public Expression Serialize(object value, JsonPath currentPath)
{
return Serialize(value, currentPath, null);
}
public ReferenceExpression(JsonPath ReferencePath)
{
this._path = ReferencePath;
}
public ReferenceExpression(string ReferencePath)
{
this._path = new JsonPath(ReferencePath);
}
/// <summary>
/// Returns a reference expression to the current data
/// </summary>
/// <param name="data">the object data</param>
/// <param name="currentPath">current path to this object</param>
/// <param name="serializer">serializer instance</param>
/// <returns>reference expression</returns>
public override Expression GetExpression(object data, JsonPath currentPath, ISerializerHandler serializer)
{
return serializer.HandleReference(data, currentPath);
}
/// <summary>
/// Gets an expression for a value by first converting it with a specific type converter and then calling Serialize. This
/// method can be called directly when using a Property Converter
/// </summary>
/// <param name="value">the value to generate an expression for</param>
/// <param name="converter">the type converter to use for conversion</param>
/// <param name="currentPath">the current path to the value</param>
/// <param name="serializer">serializer instance</param>
/// <returns>an expression for the value</returns>
public Expression GetExpression(object value, IJsonTypeConverter converter, JsonPath currentPath, ISerializerHandler serializer)
{
object convertedObject = converter.ConvertFrom(value, Context);
// call serialize again in case the new type has a converter
Expression expr = serializer.Serialize(convertedObject, currentPath, null);
serializer.SetCanReference(value); // can't reference inside the object
return expr;
}
public ReferenceExpression(JsonPath ReferencePath)
{
this._path = ReferencePath;
}
/// <summary>
/// Creates a null expression
/// </summary>
/// <param name="data">the data</param>
/// <param name="currentPath">current path</param>
/// <param name="serializer">serializer instance</param>
/// <returns>NullExpression</returns>
public override Expression GetExpression(object data, JsonPath currentPath, ISerializerHandler serializer)
{
return new NullExpression();
}
/// <summary>
/// Creates an json object expression from object data.
/// </summary>
/// <param name="data">the data to serialize</param>
/// <param name="currentPath">current path to the object</param>
/// <param name="serializer">serializer instance used to serialize key values</param>
/// <returns>json object expression</returns>
public override Expression GetExpression(object data, JsonPath currentPath, ISerializerHandler serializer)
{
TypeData handler = Context.GetTypeHandler(data.GetType());
ObjectExpression expression = new ObjectExpression();
foreach (IPropertyData prop in handler.Properties)
{
object value = prop.GetValue(data);
Expression valueExpr;
if (prop.HasConverter)
{
valueExpr = serializer.Serialize(value, currentPath.Append(prop.Name), prop.TypeConverter);
}
else
{
valueExpr = serializer.Serialize(value, currentPath.Append(prop.Name));
}
if (value != null && !ReflectionUtils.AreEquivalentTypes(value.GetType(), prop.PropertyType))
{
valueExpr = new CastExpression(value.GetType(), valueExpr);
}
expression.Add(prop.Name, valueExpr);
}
return expression;
}
public ReferenceInfo(JsonPath Path)
{
this.Path = Path;
}
/// <summary>
/// GetExpression is not valid for a CastExpression. CastExpressions should be created directly
/// during serialization whenever type information is needed.
/// </summary>
/// <param name="data">data to serialize</param>
/// <param name="currentPath">the current path to the object</param>
/// <param name="serializer">serializer instance</param>
/// <returns>expression</returns>
/// <exception cref="InvalidOperationException">This will throw an exception if called</exception>
public override Expression GetExpression(object data, JsonPath currentPath, ISerializerHandler serializer)
{
throw new InvalidOperationException("CastObjectHandler should not be called during Serialization");
}
/// <summary> /// Take an object and convert it to an expression to be serialized. Child names/indexes should be appended to the /// currentPath before serializing child objects. /// </summary> /// <param name="data">the object to convert</param> /// <param name="CurrentPath">the current path to this object from the root, used for tracking references</param> /// <param name="serializer">serializer instance for serializing child objects</param> /// <returns>an expression which represents a json structure</returns> public abstract Expression GetExpression(object data, JsonPath currentPath, ISerializerHandler serializer);
private Expression _reference; // the expression that is referenced
#endregion Fields
#region Constructors
public ReferenceExpression(string ReferencePath)
{
this._path = new JsonPath(ReferencePath);
}
