private void DeserializeMember(BsonReader bsonReader, object obj, BsonMemberMap memberMap)
{
try
{
var nominalType = memberMap.MemberType;
Type actualType;
if (bsonReader.CurrentBsonType == BsonType.Null)
{
actualType = nominalType;
}
else
{
var discriminatorConvention = BsonDefaultSerializer.LookupDiscriminatorConvention(nominalType);
actualType = discriminatorConvention.GetActualType(bsonReader, nominalType); // returns nominalType if no discriminator found
}
var serializer = memberMap.GetSerializer(actualType);
var value = serializer.Deserialize(bsonReader, nominalType, actualType, memberMap.SerializationOptions);
memberMap.Setter(obj, value);
}
catch (Exception ex)
{
var message = string.Format(
"An error occurred while deserializing the {0} {1} of class {2}: {3}", // terminating period provided by nested message
memberMap.MemberName, (memberMap.MemberInfo.MemberType == MemberTypes.Field) ? "field" : "property", obj.GetType().FullName, ex.Message);
throw new FileFormatException(message, ex);
}
}
/// <summary>
/// Deserializes an object from a BsonReader.
/// </summary>
/// <param name="bsonReader">The BsonReader.</param>
/// <param name="nominalType">The nominal type of the object.</param>
/// <param name="options">The serialization options.</param>
/// <returns>An object.</returns>
public object Deserialize(
BsonReader bsonReader,
Type nominalType,
IBsonSerializationOptions options
)
{
VerifyNominalType(nominalType);
if (bsonReader.CurrentBsonType == Bson.BsonType.Null)
{
bsonReader.ReadNull();
return(null);
}
else
{
var discriminatorConvention = BsonDefaultSerializer.LookupDiscriminatorConvention(nominalType);
var actualType = discriminatorConvention.GetActualType(bsonReader, nominalType);
if (actualType != nominalType)
{
var serializer = BsonSerializer.LookupSerializer(actualType);
if (serializer != this)
{
// in rare cases a concrete actualType might have a more specialized serializer
return(serializer.Deserialize(bsonReader, nominalType, actualType, options));
}
}
return(Deserialize(bsonReader, nominalType, actualType, options));
}
}
/// <summary>
/// Deserializes an object from a BsonReader.
/// </summary>
/// <param name="bsonReader">The BsonReader.</param>
/// <param name="nominalType">The nominal type of the object.</param>
/// <param name="options">The serialization options.</param>
/// <returns>An object.</returns>
public static object Deserialize(BsonReader bsonReader, Type nominalType, IBsonSerializationOptions options)
{
if (nominalType == typeof(BsonDocument))
{
var bsonDocument = new BsonDocument();
return(bsonDocument.Deserialize(bsonReader, nominalType, options));
}
// if nominalType is an interface find out the actualType and use it instead
if (nominalType.IsInterface)
{
var discriminatorConvention = BsonDefaultSerializer.LookupDiscriminatorConvention(nominalType);
var actualType = discriminatorConvention.GetActualType(bsonReader, nominalType);
if (actualType == nominalType)
{
var message = string.Format("Unable to determine actual type of object to deserialize. NominalType is the interface {0}.", nominalType);
throw new FileFormatException(message);
}
var serializer = LookupSerializer(actualType);
return(serializer.Deserialize(bsonReader, actualType, options));
}
else
{
var serializer = LookupSerializer(nominalType);
return(serializer.Deserialize(bsonReader, nominalType, options));
}
}
/// <summary>
/// Looks up the discriminator convention for a type.
/// </summary>
/// <param name="type">The type.</param>
/// <returns>A discriminator convention.</returns>
public static IDiscriminatorConvention LookupDiscriminatorConvention(
Type type
)
{
lock (BsonSerializer.ConfigLock) {
IDiscriminatorConvention convention;
if (!discriminatorConventions.TryGetValue(type, out convention))
{
// if there is no convention registered for object register the default one
if (!discriminatorConventions.ContainsKey(typeof(object)))
{
var defaultDiscriminatorConvention = StandardDiscriminatorConvention.Hierarchical;
discriminatorConventions.Add(typeof(object), defaultDiscriminatorConvention);
if (type == typeof(object))
{
return(defaultDiscriminatorConvention);
}
}
if (type.IsInterface)
{
// TODO: should convention for interfaces be inherited from parent interfaces?
convention = discriminatorConventions[typeof(object)];
discriminatorConventions[type] = convention;
}
else
{
// inherit the discriminator convention from the closest parent that has one
Type parentType = type.BaseType;
while (convention == null)
{
if (parentType == null)
{
var message = string.Format("No discriminator convention found for type {0}.", type.FullName);
throw new BsonSerializationException(message);
}
if (discriminatorConventions.TryGetValue(parentType, out convention))
{
break;
}
parentType = parentType.BaseType;
}
// register this convention for all types between this and the parent type where we found the convention
var unregisteredType = type;
while (unregisteredType != parentType)
{
BsonDefaultSerializer.RegisterDiscriminatorConvention(unregisteredType, convention);
unregisteredType = unregisteredType.BaseType;
}
}
}
return(convention);
}
}
// internal methods
/// <summary>
/// Gets the discriminator convention for the member type.
/// </summary>
/// <returns>The discriminator convention for the member type.</returns>
internal IDiscriminatorConvention GetDiscriminatorConvention()
{
// return a cached discriminator convention when possible
var discriminatorConvention = _cachedDiscriminatorConvention;
if (discriminatorConvention == null)
{
// it's possible but harmless for multiple threads to do the initial lookup at the same time
discriminatorConvention = BsonDefaultSerializer.LookupDiscriminatorConvention(_memberType);
_cachedDiscriminatorConvention = discriminatorConvention;
}
return(discriminatorConvention);
}
private void DeserializeMember(
BsonReader bsonReader,
object obj,
BsonMemberMap memberMap
)
{
var nominalType = memberMap.MemberType;
Type actualType;
if (bsonReader.CurrentBsonType == BsonType.Null)
{
actualType = nominalType;
}
else
{
var discriminatorConvention = BsonDefaultSerializer.LookupDiscriminatorConvention(nominalType);
actualType = discriminatorConvention.GetActualType(bsonReader, nominalType); // returns nominalType if no discriminator found
}
var serializer = memberMap.GetSerializer(actualType);
var value = serializer.Deserialize(bsonReader, nominalType, actualType, memberMap.SerializationOptions);
memberMap.Setter(obj, value);
}
/// <summary>
/// Serializes an object to a BsonWriter.
/// </summary>
/// <param name="bsonWriter">The BsonWriter.</param>
/// <param name="nominalType">The nominal type.</param>
/// <param name="value">The object.</param>
/// <param name="options">The serialization options.</param>
public void Serialize(
BsonWriter bsonWriter,
Type nominalType,
object value,
IBsonSerializationOptions options
)
{
if (value == null)
{
bsonWriter.WriteNull();
}
else
{
// Nullable types are weird because they get boxed as their underlying value type
// we can best handle that by switching the nominalType to the underlying value type
// (so VerifyNominalType doesn't fail and we don't get an unnecessary discriminator)
if (nominalType.IsGenericType && nominalType.GetGenericTypeDefinition() == typeof(Nullable <>))
{
nominalType = nominalType.GetGenericArguments()[0];
}
VerifyNominalType(nominalType);
var actualType = (value == null) ? nominalType : value.GetType();
var classMap = BsonClassMap.LookupClassMap(actualType);
bsonWriter.WriteStartDocument();
var documentOptions = (options == null) ? DocumentSerializationOptions.Defaults : (DocumentSerializationOptions)options;
BsonMemberMap idMemberMap = null;
if (documentOptions.SerializeIdFirst)
{
idMemberMap = classMap.IdMemberMap;
if (idMemberMap != null)
{
SerializeMember(bsonWriter, value, idMemberMap);
}
}
if (actualType != nominalType || classMap.DiscriminatorIsRequired || classMap.HasRootClass)
{
// never write out a discriminator for an anonymous class
if (!classMap.IsAnonymous)
{
var discriminatorConvention = BsonDefaultSerializer.LookupDiscriminatorConvention(nominalType);
var discriminator = discriminatorConvention.GetDiscriminator(nominalType, actualType);
if (discriminator != null)
{
bsonWriter.WriteName(discriminatorConvention.ElementName);
discriminator.WriteTo(bsonWriter);
}
}
}
foreach (var memberMap in classMap.MemberMaps)
{
// note: if serializeIdFirst is false then idMemberMap will be null (so no property will be skipped)
if (memberMap != idMemberMap)
{
if (memberMap == classMap.ExtraElementsMemberMap)
{
SerializeExtraElements(bsonWriter, value, memberMap);
}
else
{
SerializeMember(bsonWriter, value, memberMap);
}
}
}
bsonWriter.WriteEndDocument();
}
}
/// <summary>
/// Deserializes an object from a BsonReader.
/// </summary>
/// <param name="bsonReader">The BsonReader.</param>
/// <param name="nominalType">The nominal type of the object.</param>
/// <param name="actualType">The actual type of the object.</param>
/// <param name="options">The serialization options.</param>
/// <returns>An object.</returns>
public object Deserialize(
BsonReader bsonReader,
Type nominalType,
Type actualType,
IBsonSerializationOptions options
)
{
VerifyNominalType(nominalType);
if (bsonReader.CurrentBsonType == Bson.BsonType.Null)
{
bsonReader.ReadNull();
return(null);
}
else
{
if (actualType.IsValueType)
{
var message = string.Format("Value class {0} cannot be deserialized.", actualType.FullName);
throw new BsonSerializationException(message);
}
var classMap = BsonClassMap.LookupClassMap(actualType);
if (classMap.IsAnonymous)
{
throw new InvalidOperationException("An anonymous class cannot be deserialized.");
}
var obj = classMap.CreateInstance();
bsonReader.ReadStartDocument();
var missingElementMemberMaps = new HashSet <BsonMemberMap>(classMap.MemberMaps); // make a copy!
var discriminatorConvention = BsonDefaultSerializer.LookupDiscriminatorConvention(nominalType);
while (bsonReader.ReadBsonType() != BsonType.EndOfDocument)
{
var elementName = bsonReader.ReadName();
if (elementName == discriminatorConvention.ElementName)
{
bsonReader.SkipValue(); // skip over discriminator
continue;
}
var memberMap = classMap.GetMemberMapForElement(elementName);
if (memberMap != null && memberMap != classMap.ExtraElementsMemberMap)
{
DeserializeMember(bsonReader, obj, memberMap);
missingElementMemberMaps.Remove(memberMap);
}
else
{
if (classMap.ExtraElementsMemberMap != null)
{
DeserializeExtraElement(bsonReader, obj, elementName, classMap.ExtraElementsMemberMap);
}
else if (classMap.IgnoreExtraElements)
{
bsonReader.SkipValue();
}
else
{
var message = string.Format("Element '{0}' does not match any field or property of class {1}.", elementName, classMap.ClassType.FullName);
throw new FileFormatException(message);
}
}
}
bsonReader.ReadEndDocument();
foreach (var memberMap in missingElementMemberMaps)
{
if (memberMap.IsRequired)
{
var fieldOrProperty = (memberMap.MemberInfo.MemberType == MemberTypes.Field) ? "field" : "property";
var message = string.Format("Required element '{0}' for {1} '{2}' of class {3} is missing.", memberMap.ElementName, fieldOrProperty, memberMap.MemberName, classMap.ClassType.FullName);
throw new FileFormatException(message);
}
if (memberMap.HasDefaultValue)
{
memberMap.ApplyDefaultValue(obj);
}
}
return(obj);
}
}
/// <summary>
/// Deserializes an object from a BsonReader.
/// </summary>
/// <param name="bsonReader">The BsonReader.</param>
/// <param name="nominalType">The nominal type of the object.</param>
/// <param name="actualType">The actual type of the object.</param>
/// <param name="options">The serialization options.</param>
/// <returns>An object.</returns>
public object Deserialize(
BsonReader bsonReader,
Type nominalType,
Type actualType,
IBsonSerializationOptions options
)
{
VerifyNominalType(nominalType);
if (bsonReader.CurrentBsonType == Bson.BsonType.Null)
{
bsonReader.ReadNull();
return(null);
}
else
{
var classMap = BsonClassMap.LookupClassMap(actualType);
if (classMap.IsAnonymous)
{
throw new InvalidOperationException("Anonymous classes cannot be deserialized");
}
var obj = classMap.CreateInstance();
bsonReader.ReadStartDocument();
var missingElementMemberMaps = new HashSet <BsonMemberMap>(classMap.MemberMaps); // make a copy!
var discriminatorConvention = BsonDefaultSerializer.LookupDiscriminatorConvention(nominalType);
while (bsonReader.ReadBsonType() != BsonType.EndOfDocument)
{
var elementName = bsonReader.ReadName();
if (elementName == discriminatorConvention.ElementName)
{
bsonReader.SkipValue(); // skip over discriminator
continue;
}
var memberMap = classMap.GetMemberMapForElement(elementName);
if (memberMap != null && memberMap != classMap.ExtraElementsMemberMap)
{
DeserializeMember(bsonReader, obj, memberMap);
missingElementMemberMaps.Remove(memberMap);
}
else
{
if (classMap.ExtraElementsMemberMap != null)
{
DeserializeExtraElement(bsonReader, obj, elementName, classMap.ExtraElementsMemberMap);
}
else if (classMap.IgnoreExtraElements)
{
bsonReader.SkipValue();
}
else
{
string message = string.Format("Unexpected element: {0}", elementName);
throw new FileFormatException(message);
}
}
}
bsonReader.ReadEndDocument();
foreach (var memberMap in missingElementMemberMaps)
{
if (memberMap.IsRequired)
{
var message = string.Format("Required element is missing: {0}", memberMap.ElementName);
throw new FileFormatException(message);
}
if (memberMap.HasDefaultValue)
{
memberMap.ApplyDefaultValue(obj);
}
}
return(obj);
}
}
