public SerializationExpression BindProjector(ref Expression selector)
{
var projector = selector as SerializationExpression;
if (selector.NodeType == ExpressionType.MemberInit || selector.NodeType == ExpressionType.New)
{
var serializer = SerializerBuilder.Build(selector, _serializerRegistry);
projector = new DocumentExpression(serializer);
}
else if (projector == null || projector is PipelineExpression || projector is IFieldExpression || projector is ArrayIndexExpression)
{
var newFieldName = "__fld0";
if (projector is IFieldExpression)
{
// We don't have to do this, but it makes the output a little nicer.
newFieldName = ((IFieldExpression)projector).FieldName;
}
// the output of a $project stage must be a document, so
// if this isn't already a serialization expression and it's not
// a new expression or member init, then we need to create an
// artificial field to project the computation into.
var serializer = GetSerializer(selector.Type, selector);
selector = new FieldAsDocumentExpression(selector, newFieldName, serializer);
projector = new FieldExpression(newFieldName, serializer);
}
return(projector);
}
public IBsonSerializer GetSerializer(Type type, Expression node)
{
Ensure.IsNotNull(type, nameof(type));
IBsonSerializer serializer;
if (node != null && PreviouslyUsedSerializerFinder.TryFindSerializer(node, type, out serializer))
{
return(serializer);
}
else if (node == null || type != node.Type)
{
serializer = _serializerRegistry.GetSerializer(type);
if (node != null)
{
var childConfigurableSerializer = serializer as IChildSerializerConfigurable;
if (childConfigurableSerializer != null)
{
var nodeSerializer = GetSerializer(node.Type, node);
var deepestChildSerializer = SerializerHelper.GetDeepestChildSerializer(childConfigurableSerializer);
if (nodeSerializer.ValueType == deepestChildSerializer.ValueType)
{
serializer = SerializerHelper.RecursiveConfigureChildSerializer(childConfigurableSerializer, nodeSerializer);
}
}
}
}
else
{
serializer = SerializerBuilder.Build(node, _serializerRegistry);
}
return(serializer);
}
public static IBsonSerializer Build(Expression node, IBsonSerializerRegistry serializerRegistry)
{
var builder = new SerializerBuilder(serializerRegistry);
return(builder.Build(node));
}