//...
fsResult Internal_Deserialize(fsData data, Type storageType, ref object result, Type overrideConverterType)
{
//$ref encountered. Do before inheritance.
if (IsObjectReference(data))
{
int refId = int.Parse(data.AsDictionary[KEY_OBJECT_REFERENCE].AsString);
result = _references.GetReferenceObject(refId);
return(fsResult.Success);
}
var deserializeResult = fsResult.Success;
var objectType = result != null?result.GetType() : storageType;
Type forwardMigrationPreviousType = null;
// Gather processors and call OnBeforeDeserialize before anything
var processors = GetProcessors(objectType);
Invoke_OnBeforeDeserialize(processors, objectType, ref data);
// If the serialized state contains type information, then we need to make sure to update our
// objectType and data to the proper values so that when we construct an object instance later
// and run deserialization we run it on the proper type.
// $type
if (IsTypeSpecified(data))
{
var typeNameData = data.AsDictionary[KEY_INSTANCE_TYPE];
do
{
if (!typeNameData.IsString)
{
deserializeResult.AddMessage(string.Format("{0} value must be a string", KEY_INSTANCE_TYPE));
break;
}
var typeName = typeNameData.AsString;
var type = ReflectionTools.GetType(typeName, storageType);
if (type == null)
{
deserializeResult.AddMessage(string.Format("{0} type can not be resolved", typeName));
break;
}
var migrateAtt = type.RTGetAttribute <fsMigrateToAttribute>(true);
if (migrateAtt != null)
{
// if migrating from another type, save the original type and mutate the current type
if (!typeof(IMigratable).IsAssignableFrom(migrateAtt.targetType))
{
throw new Exception("TargetType of [fsMigrateToAttribute] must implement IMigratable<T> with T being the target type");
}
forwardMigrationPreviousType = type;
if (type.IsGenericType && migrateAtt.targetType.IsGenericTypeDefinition)
{
type = migrateAtt.targetType.MakeGenericType(type.GetGenericArguments());
}
else
{
type = migrateAtt.targetType;
}
}
if (!storageType.IsAssignableFrom(type))
{
deserializeResult.AddMessage(string.Format("Ignoring type specifier. Field or type {0} can't hold and instance of type {1}", storageType, type));
break;
}
objectType = type;
} while (false);
}
var converter = GetConverter(objectType, overrideConverterType);
if (converter == null)
{
return(fsResult.Warn(string.Format("No Converter available for {0}", objectType)));
}
// Construct an object instance if we don't have one already using actual objectType
if (ReferenceEquals(result, null) || result.GetType() != objectType)
{
result = converter.CreateInstance(data, objectType);
}
// if migrating from another type, do migration now.
if (forwardMigrationPreviousType != null)
{
//we deserialize versioning first on the old model type and then do migration
var previousInstance = GetConverter(forwardMigrationPreviousType, null).CreateInstance(data, forwardMigrationPreviousType);
TryDeserializeVersioning(ref previousInstance, ref data);
TryDeserializeMigration(ref result, ref data, forwardMigrationPreviousType, previousInstance);
}
else
{
// if not a forward migration, try deserialize versioning as normal
TryDeserializeVersioning(ref result, ref data);
}
// invoke callback with objectType
Invoke_OnBeforeDeserializeAfterInstanceCreation(processors, objectType, result, ref data);
// $id
if (IsObjectDefinition(data))
{
var sourceId = int.Parse(data.AsDictionary[KEY_OBJECT_DEFINITION].AsString);
_references.AddReferenceWithId(sourceId, result);
}
// $content
if (IsWrappedData(data))
{
data = data.AsDictionary[KEY_CONTENT];
}
// push collector
TryPush(result);
// must pass actual objectType
deserializeResult += converter.TryDeserialize(data, ref result, objectType);
if (deserializeResult.Succeeded)
{
Invoke_OnAfterDeserialize(processors, objectType, result);
}
// pop collector
TryPop(result);
return(deserializeResult);
}
private fsResult TryParseObject(out fsData obj)
{
if (Character() != '{')
{
obj = null;
return(MakeFailure("Expected initial { when parsing an object"));
}
// skip '{'
if (TryMoveNext() == false)
{
obj = null;
return(MakeFailure("Unexpected end of input when parsing an object"));
}
SkipSpace();
var result = new Dictionary <string, fsData>(
fsGlobalConfig.IsCaseSensitive ? StringComparer.Ordinal : StringComparer.OrdinalIgnoreCase);
while (HasValue() && Character() != '}')
{
fsResult failure;
// parse the key
SkipSpace();
string key;
failure = TryParseString(out key);
if (failure.Failed)
{
obj = null;
return(failure);
}
SkipSpace();
// parse the ':' after the key
if (HasValue() == false || Character() != ':' || TryMoveNext() == false)
{
obj = null;
return(MakeFailure("Expected : after key \"" + key + "\""));
}
SkipSpace();
// parse the value
fsData value;
failure = RunParse(out value);
if (failure.Failed)
{
obj = null;
return(failure);
}
result.Add(key, value);
// parse the comma
SkipSpace();
if (HasValue() && Character() == ',')
{
if (TryMoveNext() == false)
{
break;
}
SkipSpace();
}
}
// skip the final }
if (HasValue() == false || Character() != '}' || TryMoveNext() == false)
{
obj = null;
return(MakeFailure("No closing } for object"));
}
obj = new fsData(result);
return(fsResult.Success);
}
///----------------------------------------------------------------------------------------------
/// Serialize the given value.
public fsResult TrySerialize(Type storageType, object instance, out fsData data)
{
return(TrySerialize(storageType, instance, out data, null));
}
///----------------------------------------------------------------------------------------------
/// Attempts to deserialize a value from a serialized state.
public fsResult TryDeserialize(fsData data, Type storageType, ref object result)
{
return(TryDeserialize(data, storageType, ref result, null));
}
/// <summary>
/// Serialize the given value.
/// </summary>
/// <param name="storageType">The type of field/property that stores the object instance. This is
/// important particularly for inheritance, as a field storing an IInterface instance
/// should have type information included.</param>
/// <param name="overrideConverterType">An fsBaseConverter derived type that will be used to serialize
/// the object instead of the converter found via the normal discovery mechanisms.</param>
/// <param name="instance">The actual object instance to serialize.</param>
/// <param name="data">The serialized state of the object.</param>
/// <returns>If serialization was successful.</returns>
public fsResult TrySerialize(Type storageType, Type overrideConverterType, object instance, out fsData data)
{
var processors = GetProcessors(instance == null ? storageType : instance.GetType());
// 主要是是条用processors的OnBeforeSerialize和ISerializationCallbackReceiver.OnBeforeSerialize方法
Invoke_OnBeforeSerialize(processors, storageType, instance);
// 如果是null值的情况
// We always serialize null directly as null
if (ReferenceEquals(instance, null))
{
data = new fsData();
// // 调用fsObjectProcessor的OnAfterSerialize
Invoke_OnAfterSerialize(processors, storageType, instance, ref data);
return(fsResult.Success);
}
var result = InternalSerialize_1_ProcessCycles(storageType, overrideConverterType, instance, out data);
Invoke_OnAfterSerialize(processors, storageType, instance, ref data);
return(result);
}
private static void Invoke_OnBeforeDeserializeAfterInstanceCreation(List <fsObjectProcessor> processors, Type storageType, object instance, ref fsData data)
{
for (int i = 0; i < processors.Count; ++i)
{
processors[i].OnBeforeDeserializeAfterInstanceCreation(storageType, instance, ref data);
}
}
/// <summary>
/// Determines whether the specified object is equal to the current object.
/// </summary>
public bool Equals(fsData other)
{
if (other == null || Type != other.Type)
{
return(false);
}
switch (Type)
{
case fsDataType.Null:
return(true);
case fsDataType.Double:
return(AsDouble == other.AsDouble || Math.Abs(AsDouble - other.AsDouble) < double.Epsilon);
case fsDataType.Int64:
return(AsInt64 == other.AsInt64);
case fsDataType.Boolean:
return(AsBool == other.AsBool);
case fsDataType.String:
return(AsString == other.AsString);
case fsDataType.Array:
var thisList = AsList;
var otherList = other.AsList;
if (thisList.Count != otherList.Count)
{
return(false);
}
for (int i = 0; i < thisList.Count; ++i)
{
if (thisList[i].Equals(otherList[i]) == false)
{
return(false);
}
}
return(true);
case fsDataType.Object:
var thisDict = AsDictionary;
var otherDict = other.AsDictionary;
if (thisDict.Count != otherDict.Count)
{
return(false);
}
foreach (string key in thisDict.Keys)
{
if (otherDict.ContainsKey(key) == false)
{
return(false);
}
if (thisDict[key].Equals(otherDict[key]) == false)
{
return(false);
}
}
return(true);
}
throw new Exception("Unknown data type");
}
protected fsResult FailExpectedType(fsData data, params fsDataType[] types)
{
return(fsResult.Fail(GetType().Name + " expected one of " +
string.Join(", ", types.Select(t => t.ToString()).ToArray()) +
" but got " + data.Type + " in " + data));
}
private fsResult InternalDeserialize_1_CycleReference(Type overrideConverterType, fsData data, Type storageType, ref object result, out List <fsObjectProcessor> processors)
{
// We handle object references first because we could be deserializing a cyclic type that is
// inherited. If that is the case, then if we handle references after inheritances we will try
// to create an object instance for an abstract/interface type.
// While object construction should technically be two-pass, we can do it in
// one pass because of how serialization happens. We traverse the serialization
// graph in the same order during serialization and deserialization, so the first
// time we encounter an object it'll always be the definition. Any times after that
// it will be a reference. Because of this, if we encounter a reference then we
// will have *always* already encountered the definition for it.
// 判断data是否是Dict，并且是否有$ref字段
if (IsObjectReference(data))
{
int refId = int.Parse(data.AsDictionary[Key_ObjectReference].AsString);
result = _references.GetReferenceObject(refId);
processors = GetProcessors(result.GetType());
return(fsResult.Success);
}
return(InternalDeserialize_3_Inheritance(overrideConverterType, data, storageType, ref result, out processors));
//return InternalDeserialize_2_Version(overrideConverterType, data, storageType, ref result, out processors);
}
/* //PARADOXNOTION ADDITION
* private fsResult InternalDeserialize_2_Version(Type overrideConverterType, fsData data, Type storageType, ref object result, out List<fsObjectProcessor> processors) {
* if (IsVersioned(data)) {
* // data is versioned, but we might not need to do a migration
* string version = data.AsDictionary[Key_Version].AsString;
*
* fsOption<fsVersionedType> versionedType = fsVersionManager.GetVersionedType(storageType);
* if (versionedType.HasValue &&
* versionedType.Value.VersionString != version) {
*
* // we have to do a migration
* var deserializeResult = fsResult.Success;
*
* List<fsVersionedType> path;
* deserializeResult += fsVersionManager.GetVersionImportPath(version, versionedType.Value, out path);
* if (deserializeResult.Failed) {
* processors = GetProcessors(storageType);
* return deserializeResult;
* }
*
* // deserialize as the original type
* deserializeResult += InternalDeserialize_3_Inheritance(overrideConverterType, data, path[0].ModelType, ref result, out processors);
* if (deserializeResult.Failed) return deserializeResult;
*
* // TODO: we probably should be invoking object processors all along this pipeline
* for (int i = 1; i < path.Count; ++i) {
* result = path[i].Migrate(result);
* }
*
* // Our data contained an object definition ($id) that was added to _references in step 4.
* // However, in case we are doing versioning, it will contain the old version.
* // To make sure future references to this object end up referencing the migrated version,
* // we must update the reference.
* if (IsObjectDefinition(data)) {
* int sourceId = int.Parse(data.AsDictionary[Key_ObjectDefinition].AsString);
* _references.AddReferenceWithId(sourceId, result);
* }
*
* processors = GetProcessors(deserializeResult.GetType());
* return deserializeResult;
* }
* }
*
* return InternalDeserialize_3_Inheritance(overrideConverterType, data, storageType, ref result, out processors);
* }
*/
private fsResult InternalDeserialize_3_Inheritance(Type overrideConverterType, fsData data, Type storageType, ref object result, out List <fsObjectProcessor> processors)
{
var deserializeResult = fsResult.Success;
// We wait until here to actually Invoke_OnBeforeDeserialize because we do not
// have the correct set of processors to invoke until *after* we have resolved
// the proper type to use for deserialization.
processors = GetProcessors(storageType);
// 调用processors的OnBeforeDeserialize函数
Invoke_OnBeforeDeserialize(processors, storageType, ref data);
Type objectType = storageType;
// If the serialized state contains type information, then we need to make sure to update our
// objectType and data to the proper values so that when we construct an object instance later
// and run deserialization we run it on the proper type.
// data是否是dict，并且是否包含有 $type 字段
if (IsTypeSpecified(data))
{
fsData typeNameData = data.AsDictionary[Key_InstanceType];
// we wrap everything in a do while false loop so we can break out it
do
{
if (typeNameData.IsString == false)
{
deserializeResult.AddMessage(Key_InstanceType + " value must be a string (in " + data + ")");
break;
}
// 取出$type字段的值
string typeName = typeNameData.AsString;
//PARADOXNOTION ADDITION
// Type type = fsTypeCache.GetType(typeName);
//Provide storageType for when last resorting to no Namespace match
// 根据typeName，返回类型，(这里处理了泛型和其他类型)
Type type = fsTypeCache.GetType(typeName, storageType);
if (type == null)
{
deserializeResult.AddMessage("Unable to locate specified type \"" + typeName + "\"");
break;
}
if (storageType.IsAssignableFrom(type) == false)
{
deserializeResult.AddMessage("Ignoring type specifier; a field/property of type " + storageType + " cannot hold an instance of " + type);
break;
}
objectType = type;
} while (false);
}
// Construct an object instance if we don't have one already. We also need to construct
// an instance if the result type is of the wrong type, which may be the case when we
// have a versioned import graph.
// 实例化一个实例出来
if (ReferenceEquals(result, null) || result.GetType() != objectType)
{
result = GetConverter(objectType, overrideConverterType).CreateInstance(data, objectType);
}
// We call OnBeforeDeserializeAfterInstanceCreation here because we still want to invoke the
// method even if the user passed in an existing instance.
// 调用processors.OnBeforeDeserializeAfterInstanceCreation
Invoke_OnBeforeDeserializeAfterInstanceCreation(processors, storageType, result, ref data);
// NOTE: It is critically important that we pass the actual objectType down instead of
// using result.GetType() because it is not guaranteed that result.GetType()
// will equal objectType, especially because some converters are known to
// return dummy values for CreateInstance() (for example, the default behavior
// for structs is to just return the type of the struct).
return(deserializeResult += InternalDeserialize_4_Cycles(overrideConverterType, data, objectType, ref result));
}
/* //PARADOXNOTION ADDITION
* private fsResult InternalSerialize_3_ProcessVersioning(Type overrideConverterType, object instance, out fsData data) {
* // note: We do not have to take a Type parameter here, since at this point in the serialization
* // algorithm inheritance has *always* been handled. If we took a type parameter, it will
* // *always* be equal to instance.GetType(), so why bother taking the parameter?
*
* // Check to see if there is versioning information for this type. If so, then we need to serialize it.
* fsOption<fsVersionedType> optionalVersionedType = fsVersionManager.GetVersionedType(instance.GetType());
* if (optionalVersionedType.HasValue) {
* fsVersionedType versionedType = optionalVersionedType.Value;
*
* // Serialize the actual object content; we'll just wrap it with versioning metadata here.
* var result = InternalSerialize_4_Converter(overrideConverterType, instance, out data);
* if (result.Failed) return result;
*
* // Add the versioning information
* EnsureDictionary(data);
* data.AsDictionary[Key_Version] = new fsData(versionedType.VersionString);
*
* return result;
* }
*
* // This type has no versioning information -- directly serialize it using the selected converter.
* return InternalSerialize_4_Converter(overrideConverterType, instance, out data);
* }
*/
private fsResult InternalSerialize_4_Converter(Type overrideConverterType, object instance, out fsData data)
{
var instanceType = instance.GetType();
// 这里，就会进入不同的converter的TrySerialize中
return(GetConverter(instanceType, overrideConverterType).TrySerialize(instance, out data, instanceType));
}
private fsResult InternalSerialize_2_Inheritance(Type storageType, Type overrideConverterType, object instance, out fsData data)
{
// Serialize the actual object with the field type being the same as the object
// type so that we won't go into an infinite loop.
//var serializeResult = InternalSerialize_3_ProcessVersioning(overrideConverterType, instance, out data);
var serializeResult = InternalSerialize_4_Converter(overrideConverterType, instance, out data);
if (serializeResult.Failed)
{
return(serializeResult);
}
// Do we need to add type information? If the field type and the instance type are different
// then we will not be able to recover the correct instance type from the field type when
// we deserialize the object.
//
// Note: We allow converters to request that we do *not* add type information.
// 假如storageType != instance.GetType()的话，就需要存储[$type]
if (storageType != instance.GetType() &&
GetConverter(storageType, overrideConverterType).RequestInheritanceSupport(storageType))
{
// Add the inheritance metadata,继承的数据
EnsureDictionary(data);
data.AsDictionary[Key_InstanceType] = new fsData(instance.GetType().FullName);
}
return(serializeResult);
}
private fsResult InternalSerialize_1_ProcessCycles(Type storageType, Type overrideConverterType, object instance, out fsData data)
{
// We have an object definition to serialize.
try {
// Note that we enter the reference group at the beginning of serialization so that we support
// references that are at equal serialization levels, not just nested serialization levels, within
// the given subobject. A prime example is serialization a list of references.
_references.Enter();
// This type does not need cycle support.
// 获得instance.GetType()对应的converter
var converter = GetConverter(instance.GetType(), overrideConverterType);
// 判断是否需要循环，这里是不循环的情况
if (converter.RequestCycleSupport(instance.GetType()) == false)
{
return(InternalSerialize_2_Inheritance(storageType, overrideConverterType, instance, out data));
}
// 当instance IsClass || IsInterface; 才会执行下面的
// We've already serialized this object instance (or it is pending higher up on the call stack).
// Just serialize a reference to it to escape the cycle.
//
// note: We serialize the int as a string to so that we don't lose any information
// in a conversion to/from double.
// 使用了引用实例的情况,直接返回fsResult.Success
if (_references.IsReference(instance))
{
// 用Dict创建一个fsData，
data = fsData.CreateDictionary();
_lazyReferenceWriter.WriteReference(_references.GetReferenceId(instance), data.AsDictionary);
return(fsResult.Success);
}
// 简单理解为记录instance到_references中
// Mark inside the object graph that we've serialized the instance. We do this *before*
// serialization so that if we get back into this function recursively, it'll already
// be marked and we can handle the cycle properly without going into an infinite loop.
_references.MarkSerialized(instance);
// We've created the cycle metadata, so we can now serialize the actual object.
// InternalSerialize will handle inheritance correctly for us.
var result = InternalSerialize_2_Inheritance(storageType, overrideConverterType, instance, out data);
if (result.Failed)
{
return(result);
}
_lazyReferenceWriter.WriteDefinition(_references.GetReferenceId(instance), data);
return(result);
}
finally {
if (_references.Exit())
{
_lazyReferenceWriter.Clear();
}
}
}
/// <summary> /// Serialize the actual object into the given data storage. /// </summary> /// <param name="instance">The object instance to serialize. This will never be null.</param> /// <param name="serialized">The serialized state.</param> /// <param name="storageType">The field/property type that is storing this instance.</param> /// <returns>If serialization was successful.</returns> public abstract fsResult TrySerialize(object instance, out fsData serialized, Type storageType);
private static void Invoke_OnAfterSerialize(List <fsObjectProcessor> processors, Type storageType, object instance, ref fsData data)
{
// We run the after calls in reverse order; this significantly reduces the interaction burden between
// multiple processors - it makes each one much more independent and ignorant of the other ones.
for (int i = processors.Count - 1; i >= 0; --i)
{
processors[i].OnAfterSerialize(storageType, instance, ref data);
}
}
/// <summary> /// Deserialize data into the object instance. /// </summary> /// <param name="data">Serialization data to deserialize from.</param> /// <param name="instance">The object instance to deserialize into.</param> /// <param name="storageType">The field/property type that is storing the instance.</param> /// <returns>True if serialization was successful, false otherwise.</returns> public abstract fsResult TryDeserialize(fsData data, ref object instance, Type storageType);
private static void Invoke_OnBeforeDeserialize(List <fsObjectProcessor> processors, Type storageType, ref fsData data)
{
for (int i = 0; i < processors.Count; ++i)
{
processors[i].OnBeforeDeserialize(storageType, ref data);
}
}
protected fsResult CheckKey(fsData data, string key, out fsData subitem)
{
return(CheckKey(data.AsDictionary, key, out subitem));
}
/// <summary>
/// Helper method that simply forwards the call to TrySerialize(typeof(T), instance, out data);
/// </summary>
public fsResult TrySerialize <T>(T instance, out fsData data)
{
return(TrySerialize(typeof(T), instance, out data));
}