/// <summary>
/// Builds a <see cref="TypeToRegisterForBson"/> for a type using the most sensible settings,
/// with a specified <see cref="IStringSerializeAndDeserialize"/> to use everywhere the type appears.
/// </summary>
/// <param name="type">The type to register.</param>
/// <param name="stringSerializer">The string serializer to use for <paramref name="type"/>.</param>
/// <returns>
/// The type to register for BSON serialization.
/// </returns>
public static TypeToRegisterForBson ToTypeToRegisterForBsonUsingStringSerializer(
this Type type,
IStringSerializeAndDeserialize stringSerializer)
{
if (type == null)
{
throw new ArgumentNullException(nameof(type));
}
if (stringSerializer == null)
{
throw new ArgumentNullException(nameof(stringSerializer));
}
var serializer = StringSerializerBackedBsonSerializer.Build(type, stringSerializer);
IBsonSerializer BsonSerializerBuilderFunc() => serializer;
var bsonSerializerBuilder = new BsonSerializerBuilder(BsonSerializerBuilderFunc, BsonSerializerOutputKind.String);
var result = new TypeToRegisterForBson(type, MemberTypesToInclude.None, RelatedTypesToInclude.Default, bsonSerializerBuilder, null);
return(result);
}
/// <summary>
/// Gets the serializer to use for a given type.
/// </summary>
/// <param name="type">The type to serialize.</param>
/// <param name="defaultToObjectSerializer">If true, then returns <see cref="ObjectSerializer"/> when the serializer cannot be determined. Otherwise, returns null.</param>
/// <returns>
/// The serializer to use for the specified type.
/// </returns>
public static IBsonSerializer GetAppropriateSerializer(
this Type type,
bool defaultToObjectSerializer)
{
if (type == null)
{
throw new ArgumentNullException(nameof(type));
}
IBsonSerializer result;
if (type == typeof(string))
{
result = new StringSerializer();
}
else if (type == typeof(Guid))
{
result = new GuidSerializer();
}
else if (type.IsEnum)
{
result = typeof(EnumStringBsonSerializer <>).MakeGenericType(type).Construct <IBsonSerializer>();
}
else if (type.IsClosedNullableType())
{
result = typeof(NullableBsonSerializer <>).MakeGenericType(Nullable.GetUnderlyingType(type)).Construct <IBsonSerializer>();
}
else if (type == typeof(DateTime))
{
result = new StringSerializerBackedBsonSerializer <DateTime>(DateTimeStringSerializer);
}
else if (type.IsClosedSystemDictionaryType())
{
var keyType = type.GetClosedSystemDictionaryKeyType();
var valueType = type.GetClosedSystemDictionaryValueType();
// It very much seems like defaultToObjectSerializer should be false, consistent with
// what we do for array and collection elements. However, unit tests fail when we change to false.
// We are not sure why and need to dig-in in the future. We do know that using ObjectSerializer
// still allows for dictionary keys and values to use a custom/registered serializer.
var keySerializer = GetAppropriateSerializer(keyType, defaultToObjectSerializer: true);
var valueSerializer = GetAppropriateSerializer(valueType, defaultToObjectSerializer: true);
result = typeof(DictionaryBsonSerializer <, ,>).MakeGenericType(type, keyType, valueType).Construct <IBsonSerializer>(DictionaryRepresentation.ArrayOfDocuments, keySerializer, valueSerializer);
}
else if (type.IsArray)
{
var elementType = type.GetElementType();
// Don't default to ObjectSerializer because if there is no element serializer we want BSON to find
// an existing registered serializer or fallback to the registered class map for the type.
var elementSerializer = GetAppropriateSerializer(elementType, defaultToObjectSerializer: false);
result = elementSerializer == null
? typeof(ArraySerializer <>).MakeGenericType(elementType).Construct <IBsonSerializer>()
: typeof(ArraySerializer <>).MakeGenericType(elementType).Construct <IBsonSerializer>(elementSerializer);
}
else if (type.IsClosedSystemCollectionType())
{
var elementType = type.GetClosedSystemCollectionElementType();
// Don't default to ObjectSerializer because if there is no element serializer we want BSON to find
// an existing registered serializer or fallback to the registered class map for the type.
var elementSerializer = GetAppropriateSerializer(elementType, defaultToObjectSerializer: false);
result = typeof(CollectionBsonSerializer <,>).MakeGenericType(type, elementType).Construct <IBsonSerializer>(elementSerializer);
}
else
{
result = defaultToObjectSerializer ? new ObjectSerializer() : null;
}
return(result);
}
