private Expression BuildProjector(Expression selector, ProjectionBindingContext context)
{
var selectorNode = selector;
if (!(selectorNode is ISerializationExpression))
{
var serializer = SerializerBuilder.Build(selector, context.SerializerRegistry);
BsonSerializationInfo info;
switch (selector.NodeType)
{
case ExpressionType.MemberInit:
case ExpressionType.New:
info = new BsonSerializationInfo(null, serializer, serializer.ValueType);
break;
default:
// this occurs when a computed field is used. This is a magic string
// that shouldn't ever be reference anywhere else...
info = new BsonSerializationInfo("__fld0", serializer, serializer.ValueType);
break;
}
selectorNode = new SerializationExpression(selector, info);
}
return selectorNode;
}
public override Expression Bind(ProjectionExpression projection, ProjectionBindingContext context, MethodCallExpression node, IEnumerable<Expression> arguments)
{
LambdaExpression aggregator;
if (node.Method.Name.EndsWith("Async"))
{
aggregator = CreateAsyncAggregator();
}
else
{
aggregator = CreateSyncAggregator();
}
var source = projection.Source;
var argument = arguments.FirstOrDefault();
if (argument != null && ExtensionExpressionVisitor.IsLambda(argument))
{
source = BindPredicate(projection, context, source, argument);
}
source = new TakeExpression(source, 1);
var serializer = context.SerializerRegistry.GetSerializer(typeof(int));
var accumulator = new AccumulatorExpression(typeof(int), AccumulatorType.Count, null);
var serializationAccumulator = new SerializationExpression(
accumulator,
new BsonSerializationInfo("__agg0", serializer, serializer.ValueType));
var rootAccumulator = new RootAccumulatorExpression(source, serializationAccumulator);
return new ProjectionExpression(
rootAccumulator,
serializationAccumulator,
aggregator);
}
public override Expression Bind(ProjectionExpression projection, ProjectionBindingContext context, MethodCallExpression node, IEnumerable<Expression> arguments)
{
// OfType is two operations in one. First we create WhereExpression
// for the test. Second, we want to issue a conversion projection
// using the selector parameter of a ProjectionExpression such that
// the conversion will be propogated to all future expressions.
var newType = node.Method.GetGenericArguments()[0];
var parameter = Expression.Parameter(projection.Projector.Type);
var predicate = Expression.Lambda(
Expression.TypeIs(parameter, newType),
parameter);
var source = BindPredicate(projection, context, projection.Source, predicate);
var serializer = context.SerializerRegistry.GetSerializer(newType);
var info = new BsonSerializationInfo(null, serializer, newType);
var projector = new SerializationExpression(
Expression.Convert(projection.Projector, newType),
info);
return new ProjectionExpression(
source,
projector);
}
protected override Expression VisitSerialization(SerializationExpression node)
{
if (node.SerializationInfo.ElementName != null)
{
_serializationExpressions.Add(node);
}
return(node);
}
public PipelineExpression(Expression source, SerializationExpression projector, ResultOperator resultOperator)
{
_source = Ensure.IsNotNull(source, nameof(source));
_projector = Ensure.IsNotNull(projector, nameof(projector));
_resultOperator = resultOperator;
_type = _resultOperator == null ?
typeof(IEnumerable<>).MakeGenericType(_projector.Type) :
_resultOperator.Type;
}
public PipelineExpression Update(Expression source, SerializationExpression projector, ResultOperator resultOperator)
{
if (source != _source ||
projector != _projector ||
resultOperator != _resultOperator)
{
return new PipelineExpression(source, projector, resultOperator);
}
return this;
}
public PipelineExpression Update(Expression source, SerializationExpression projector, ResultOperator resultOperator)
{
if (source != _source ||
projector != _projector ||
resultOperator != _resultOperator)
{
return(new PipelineExpression(source, projector, resultOperator));
}
return(this);
}
public Expression Bind(ProjectionExpression projection, ProjectionBindingContext context, MethodCallExpression node, IEnumerable<Expression> arguments)
{
var distinct = new DistinctExpression(projection.Source, projection.Projector);
var serializer = SerializerBuilder.Build(projection.Projector, context.SerializerRegistry);
var info = new BsonSerializationInfo("_id", serializer, serializer.ValueType);
var projector = new SerializationExpression(projection.Projector, info);
return new ProjectionExpression(
distinct,
projector);
}
public Expression Bind(ProjectionExpression projection, ProjectionBindingContext context, MethodCallExpression node, IEnumerable<Expression> arguments)
{
var collectionLambda = ExtensionExpressionVisitor.GetLambda(arguments.First());
var binder = new AccumulatorBinder(context.GroupMap, context.SerializerRegistry);
binder.RegisterParameterReplacement(collectionLambda.Parameters[0], projection.Projector);
var collectionSelector = binder.Bind(collectionLambda.Body) as SerializationExpression;
if (collectionSelector == null)
{
var message = string.Format("Unable to determine the collection selector in the tree: {0}", node.ToString());
throw new NotSupportedException(message);
}
var collectionArraySerializer = collectionSelector.SerializationInfo.Serializer as IBsonArraySerializer;
BsonSerializationInfo collectionItemSerializationInfo;
if (collectionArraySerializer == null || !collectionArraySerializer.TryGetItemSerializationInfo(out collectionItemSerializationInfo))
{
var message = string.Format("The collection selector's serializer must implement IBsonArraySerializer: {0}", node.ToString());
throw new NotSupportedException(message);
}
Expression resultSelector;
if (arguments.Count() == 2)
{
var resultLambda = ExtensionExpressionVisitor.GetLambda(arguments.Last());
binder.RegisterParameterReplacement(resultLambda.Parameters[0], projection.Projector);
binder.RegisterParameterReplacement(
resultLambda.Parameters[1],
new SerializationExpression(
resultLambda.Parameters[1],
collectionItemSerializationInfo.WithNewName(collectionSelector.SerializationInfo.ElementName)));
resultSelector = binder.Bind(resultLambda.Body);
}
else
{
resultSelector = new SerializationExpression(
collectionSelector,
collectionItemSerializationInfo.WithNewName(collectionSelector.SerializationInfo.ElementName));
}
var projector = BuildProjector(resultSelector, context);
return new ProjectionExpression(
new SelectManyExpression(
projection.Source,
collectionSelector,
resultSelector),
projector);
}
public PipelineExpression(Expression source, SerializationExpression projector, ResultOperator resultOperator)
{
_source = Ensure.IsNotNull(source, nameof(source));
_projector = Ensure.IsNotNull(projector, nameof(projector));
_resultOperator = resultOperator;
if (_resultOperator == null)
{
_serializer = SerializerHelper.CreateEnumerableSerializer(_projector.Serializer);
_type = typeof(IEnumerable<>).MakeGenericType(_projector.Type);
}
else
{
_serializer = _resultOperator.Serializer;
_type = _resultOperator.Type;
}
}
public PipelineExpression(Expression source, SerializationExpression projector, ResultOperator resultOperator)
{
_source = Ensure.IsNotNull(source, nameof(source));
_projector = Ensure.IsNotNull(projector, nameof(projector));
_resultOperator = resultOperator;
if (_resultOperator == null)
{
_serializer = SerializerHelper.CreateEnumerableSerializer(_projector.Serializer);
_type = typeof(IEnumerable <>).MakeGenericType(_projector.Type);
}
else
{
_serializer = _resultOperator.Serializer;
_type = _resultOperator.Type;
}
}
private GroupIdExpression BindId(ProjectionExpression projection, ProjectionBindingContext context, Expression node)
{
var lambda = ExtensionExpressionVisitor.GetLambda(node);
var binder = new AccumulatorBinder(context.GroupMap, context.SerializerRegistry);
binder.RegisterParameterReplacement(lambda.Parameters[0], projection.Projector);
var selector = binder.Bind(lambda.Body);
if (!(selector is ISerializationExpression))
{
var serializer = SerializerBuilder.Build(selector, context.SerializerRegistry);
selector = new SerializationExpression(
selector,
new BsonSerializationInfo(null, serializer, serializer.ValueType));
}
return new GroupIdExpression(selector, ((ISerializationExpression)selector).SerializationInfo);
}
public override Expression Bind(Expressions.ProjectionExpression projection, ProjectionBindingContext context, System.Linq.Expressions.MethodCallExpression node, IEnumerable<System.Linq.Expressions.Expression> arguments)
{
var aggregatorName = "Single";
var returnType = node.Method.ReturnType;
if (node.Method.Name.EndsWith("Async"))
{
aggregatorName += "Async";
returnType = returnType.GetGenericArguments()[0];
}
var aggregator = CreateAggregator(aggregatorName, returnType);
var source = projection.Source;
var argument = arguments.FirstOrDefault();
if (argument != null && ExtensionExpressionVisitor.IsLambda(argument))
{
var lambda = ExtensionExpressionVisitor.GetLambda(argument);
var binder = new AccumulatorBinder(context.GroupMap, context.SerializerRegistry);
binder.RegisterParameterReplacement(lambda.Parameters[0], projection.Projector);
argument = binder.Bind(lambda.Body);
}
else
{
argument = projection.Projector;
var select = source as SelectExpression;
if (select != null)
{
source = select.Source;
}
}
var serializer = context.SerializerRegistry.GetSerializer(returnType);
var accumulator = new AccumulatorExpression(returnType, AccumulatorType, argument);
var serializationAccumulator = new SerializationExpression(
accumulator,
new BsonSerializationInfo("__agg0", serializer, serializer.ValueType));
var rootAccumulator = new RootAccumulatorExpression(source, serializationAccumulator);
return new ProjectionExpression(
rootAccumulator,
serializationAccumulator,
aggregator);
}
protected internal override Expression VisitCorrelatedGroupBy(CorrelatedGroupByExpression node)
{
if (_lookup != null && _lookup.Contains(node.CorrelationId))
{
var source = Visit(node.Source);
var accumulators = new List<SerializationExpression>();
var comparer = new ExpressionComparer();
foreach (var correlatedAccumulator in _lookup[node.CorrelationId])
{
var index = accumulators.FindIndex(x => comparer.Compare(x.Expression, correlatedAccumulator.Accumulator));
if (index == -1)
{
var serializer = _serializerRegistry.GetSerializer(correlatedAccumulator.Type);
var info = new BsonSerializationInfo(
"__agg" + accumulators.Count,
serializer,
serializer.ValueType);
var serializationExpression = new SerializationExpression(correlatedAccumulator.Accumulator, info);
accumulators.Add(serializationExpression);
_map[correlatedAccumulator] = serializationExpression;
}
else
{
_map[correlatedAccumulator] = accumulators[index];
}
}
node = node.Update(
source,
node.Id,
accumulators.OfType<Expression>());
}
return base.VisitCorrelatedGroupBy(node);
}
private Expression BindSelector(ProjectionExpression projection, ProjectionBindingContext context, Expression id, Expression node)
{
var lambda = ExtensionExpressionVisitor.GetLambda(node);
var binder = new AccumulatorBinder(context.GroupMap, context.SerializerRegistry);
var serializer = SerializerBuilder.Build(projection.Projector, context.SerializerRegistry);
var sequenceSerializer = (IBsonSerializer)Activator.CreateInstance(
typeof(ArraySerializer<>).MakeGenericType(projection.Projector.Type),
new object[] { serializer });
var sequenceInfo = new BsonSerializationInfo(
null,
sequenceSerializer,
sequenceSerializer.ValueType);
var sequenceExpression = new SerializationExpression(
lambda.Parameters[1],
sequenceInfo);
binder.RegisterParameterReplacement(lambda.Parameters[0], id);
binder.RegisterParameterReplacement(lambda.Parameters[1], sequenceExpression);
var correlationId = Guid.NewGuid();
context.GroupMap.Add(sequenceExpression, correlationId);
var bound = binder.Bind(lambda.Body);
return CorrelatedAccumulatorRemover.Remove(bound, correlationId);
}
protected internal override Expression VisitSerialization(SerializationExpression node)
{
if (node.SerializationInfo.ElementName != null && node.SerializationInfo.ElementName.StartsWith(_oldName))
{
return new SerializationExpression(
node.Expression,
node.SerializationInfo.WithNewName(GetReplacementName(node.SerializationInfo.ElementName)));
}
return base.VisitSerialization(node);
}
public PipelineExpression(Expression source, SerializationExpression projector)
: this(source, projector, null)
{
}
protected internal override Expression VisitSerialization(SerializationExpression node)
{
if (node.SerializationInfo.Serializer.ValueType == _valueType)
{
_serializer = node.SerializationInfo.Serializer;
return node;
}
return base.VisitSerialization(node);
}
private BsonClassMap BuildClassMap(Type type, ProjectionMapping mapping)
{
if (type == null || type == typeof(object))
{
return null;
}
var baseClassMap = BuildClassMap(type.BaseType, mapping);
if (baseClassMap != null)
{
baseClassMap.Freeze();
}
var classMap = new BsonClassMap(type, baseClassMap);
foreach (var memberMapping in mapping.Members.Where(x => x.Member.DeclaringType == type))
{
var serializationExpression = memberMapping.Expression as ISerializationExpression;
if (serializationExpression == null)
{
var serializer = Build(memberMapping.Expression);
var serializationInfo = new BsonSerializationInfo(
memberMapping.Member.Name,
serializer,
GetMemberType(memberMapping.Member));
serializationExpression = new SerializationExpression(
memberMapping.Expression,
serializationInfo);
}
var memberMap = classMap.MapMember(memberMapping.Member)
.SetSerializer(serializationExpression.SerializationInfo.Serializer)
.SetElementName(memberMapping.Member.Name);
if (classMap.IdMemberMap == null && serializationExpression is GroupIdExpression)
{
classMap.SetIdMember(memberMap);
}
}
return classMap;
}
protected internal virtual Expression VisitSerialization(SerializationExpression node)
{
return(node.Update(Visit(node.Expression)));
}
protected virtual Expression VisitSerialization(SerializationExpression node)
{
return(node);
}
public PipelineExpression(Expression source, SerializationExpression projector)
: this(source, projector, null)
{
}
private bool CompareSerialization(SerializationExpression a, SerializationExpression b)
{
return(Compare(a.Expression, b.Expression));
}
protected internal virtual Expression VisitSerialization(SerializationExpression node)
{
return node.Update(Visit(node.Expression));
}
private BsonValue BuildSerialization(SerializationExpression node)
{
if (string.IsNullOrWhiteSpace(node.SerializationInfo.ElementName))
{
return BuildValue(node.Expression);
}
return "$" + node.SerializationInfo.ElementName;
}
