internal override Expression VisitMemberAccess(MemberExpression m)
{
Debug.Assert(m != null, "m != null");
this.leafExpressionIsMemberAccess = true;
// Only allowed to project entities
if (!ClientTypeUtil.TypeOrElementTypeIsEntity(m.Expression.Type) ||
IsCollectionProducingExpression(m.Expression))
{
throw new NotSupportedException(Strings.ALinq_ExpressionNotSupportedInProjectionToEntity(this.type, m.ToString()));
}
PropertyInfo pi;
Expression boundTarget;
if (ResourceBinder.PatternRules.MatchNonPrivateReadableProperty(m, out pi, out boundTarget))
{
Expression e = base.VisitMemberAccess(m);
Type convertedType;
ResourceBinder.StripTo <Expression>(m.Expression, out convertedType);
this.builder.AppendPropertyToPath(pi, convertedType, this.context);
this.leafExpressionIsMemberAccess = false;
return(e);
}
throw new NotSupportedException(Strings.ALinq_ExpressionNotSupportedInProjectionToEntity(this.type, m.ToString()));
}
internal override Expression VisitConditional(ConditionalExpression conditional)
{
Expression expressionBeforeNormalization = this.GetExpressionBeforeNormalization(conditional);
if (expressionBeforeNormalization != conditional)
{
return(this.Visit(expressionBeforeNormalization));
}
ResourceBinder.PatternRules.MatchNullCheckResult nullCheck = ResourceBinder.PatternRules.MatchNullCheck(this.pathBuilder.LambdaParameterInScope, conditional);
if (!nullCheck.Match || !ClientTypeUtil.TypeOrElementTypeIsEntity(ResourceBinder.StripConvertToAssignable(nullCheck.TestToNullExpression).Type))
{
Expression test = null;
if (nullCheck.Match)
{
Expression left = this.Visit(nullCheck.TestToNullExpression);
if (left.NodeType == ExpressionType.Convert)
{
left = ((UnaryExpression)left).Operand;
}
test = Expression.MakeBinary(ExpressionType.Equal, left, Expression.Constant(null));
}
if (test == null)
{
test = this.Visit(conditional.Test);
}
Expression ifTrue = this.Visit(conditional.IfTrue);
Expression ifFalse = this.Visit(conditional.IfFalse);
if (((test != conditional.Test) || (ifTrue != conditional.IfTrue)) || (ifFalse != conditional.IfFalse))
{
return(Expression.Condition(test, ifTrue, ifFalse, ifTrue.Type.IsAssignableFrom(ifFalse.Type) ? ifTrue.Type : ifFalse.Type));
}
}
return(this.RebindConditionalNullCheck(conditional, nullCheck));
}
/// <summary>Builds the Uri for the expression passed in.</summary>
/// <param name="e">The expression to translate into a Uri</param>
/// <returns>Query components</returns>
internal QueryComponents Translate(Expression e)
{
Uri uri;
Version version;
bool addTrailingParens = false;
Dictionary <Expression, Expression> normalizerRewrites = null;
// short cut analysis if just a resource set or singleton resource.
// note - to be backwards compatible with V1, will only append trailing () for queries
// that include more then just a resource set.
if (!(e is QueryableResourceExpression))
{
normalizerRewrites = new Dictionary <Expression, Expression>(ReferenceEqualityComparer <Expression> .Instance);
e = Evaluator.PartialEval(e);
e = ExpressionNormalizer.Normalize(e, normalizerRewrites);
e = ResourceBinder.Bind(e, this.Context);
addTrailingParens = true;
}
UriWriter.Translate(this.Context, addTrailingParens, e, out uri, out version);
ResourceExpression re = e as ResourceExpression;
Type lastSegmentType = re.Projection == null ? re.ResourceType : re.Projection.Selector.Parameters[0].Type;
LambdaExpression selector = re.Projection == null ? null : re.Projection.Selector;
return(new QueryComponents(uri, version, lastSegmentType, selector, normalizerRewrites));
}
internal override Expression VisitMemberAccess(MemberExpression m)
{
PropertyInfo info;
Expression expression;
Type type = m.Expression.Type;
this.leafExpressionIsMemberAccess = true;
if (PrimitiveType.IsKnownNullableType(type))
{
this.leafExpressionIsMemberAccess = false;
return(base.VisitMemberAccess(m));
}
if (ProjectionAnalyzer.IsCollectionProducingExpression(m.Expression))
{
throw new NotSupportedException(System.Data.Services.Client.Strings.ALinq_ExpressionNotSupportedInProjection(this.type, m.ToString()));
}
if (!ResourceBinder.PatternRules.MatchNonPrivateReadableProperty(m, out info, out expression))
{
throw new NotSupportedException(System.Data.Services.Client.Strings.ALinq_ExpressionNotSupportedInProjection(this.type, m.ToString()));
}
Expression expression2 = base.VisitMemberAccess(m);
if (ClientTypeUtil.TypeOrElementTypeIsEntity(type))
{
Type type2;
ResourceBinder.StripTo <Expression>(m.Expression, out type2);
this.box.AppendPropertyToPath(info, type2, this.context);
this.leafExpressionIsMemberAccess = false;
}
return(expression2);
}
/// <summary>
/// QueryableResourceExpression visit method.
/// </summary>
/// <param name="rse">QueryableResourceExpression expression to visit</param>
/// <returns>Visited QueryableResourceExpression expression</returns>
internal override Expression VisitQueryableResourceExpression(QueryableResourceExpression rse)
{
if ((ResourceExpressionType)rse.NodeType == ResourceExpressionType.ResourceNavigationProperty)
{
if (rse.IsOperationInvocation && !(rse.Source is QueryableResourceExpression))
{
var normalizerRewrites = new Dictionary <Expression, Expression>(ReferenceEqualityComparer <Expression> .Instance);
var e = Evaluator.PartialEval(rse.Source);
e = ExpressionNormalizer.Normalize(e, normalizerRewrites);
e = ResourceBinder.Bind(e, this.context);
this.Visit(e);
}
else
{
this.Visit(rse.Source);
}
this.uriBuilder.Append(UriHelper.FORWARDSLASH).Append(this.ExpressionToString(rse.MemberExpression, /*inPath*/ true));
}
else if (rse.MemberExpression != null)
{
// this is a resource set expression
// we should be at the very beginning of
// the URI
Debug.Assert(this.uriBuilder.Length == 0, "The builder is not empty while we are adding a resourceset");
string entitySetName = (String)((ConstantExpression)rse.MemberExpression).Value;
this.uriBuilder.Append(this.context.BaseUriResolver.GetEntitySetUri(entitySetName));
}
else
{
this.uriBuilder.Append(this.context.BaseUriResolver.BaseUriOrNull);
}
WebUtil.RaiseVersion(ref this.uriVersion, rse.UriVersion);
if (rse.ResourceTypeAs != null)
{
this.uriBuilder.Append(UriHelper.FORWARDSLASH);
UriHelper.AppendTypeSegment(this.uriBuilder, rse.ResourceTypeAs, this.context, /*inPath*/ true, ref this.uriVersion);
}
if (rse.KeyPredicateConjuncts.Count > 0)
{
this.context.UrlKeyDelimiter.AppendKeyExpression(rse.GetKeyProperties(), kvp => ClientTypeUtil.GetServerDefinedName(kvp.Key), kvp => kvp.Value.Value, this.uriBuilder);
}
if (rse.IsOperationInvocation)
{
this.VisitOperationInvocation(rse);
}
if (rse.CountOption == CountOption.CountSegment)
{
// append $count segment: /$count
this.uriBuilder.Append(UriHelper.FORWARDSLASH).Append(UriHelper.DOLLARSIGN).Append(UriHelper.COUNT);
}
this.VisitQueryOptions(rse);
return(rse);
}
internal ProjectionPathSegment(ProjectionPath startPath, MemberExpression memberExpression)
{
this.StartPath = startPath;
Expression expression = ResourceBinder.StripTo <Expression>(memberExpression.Expression);
this.Member = memberExpression.Member.Name;
this.ProjectionType = memberExpression.Type;
this.SourceTypeAs = (expression.NodeType == ExpressionType.TypeAs) ? expression.Type : null;
}
/// <summary>Gets a rewrite for the specified expression; null if none is found.</summary>
/// <param name="expression">Expression to match.</param>
/// <returns>A rewrite for the expression; possibly null.</returns>
internal Expression GetRewrite(Expression expression)
{
Debug.Assert(expression != null, "expression != null");
List <string> names = new List <string>();
// This could be a MemberAccess wrapped in a type conversion, so strip off unnecessary conversions for each loop iteration.
// E.g. (p.BestFriend As Person) instead of just p.BestFriend
expression = ResourceBinder.StripTo <Expression>(expression);
while (expression.NodeType == ExpressionType.MemberAccess || expression.NodeType == ExpressionType.TypeAs)
{
if (expression.NodeType == ExpressionType.MemberAccess)
{
MemberExpression member = (MemberExpression)expression;
names.Add(member.Member.Name);
expression = ResourceBinder.StripTo <Expression>(member.Expression);
}
else
{
expression = ResourceBinder.StripTo <Expression>(((UnaryExpression)expression).Operand);
}
}
Expression result = null;
foreach (var rewrite in this.rewrites)
{
if (rewrite.Root != expression)
{
continue;
}
if (names.Count != rewrite.MemberNames.Length)
{
continue;
}
bool match = true;
for (int i = 0; i < names.Count && i < rewrite.MemberNames.Length; i++)
{
if (names[names.Count - i - 1] != rewrite.MemberNames[i])
{
match = false;
break;
}
}
if (match)
{
result = rewrite.RewriteExpression;
break;
}
}
return(result);
}
internal static void CheckChainedSequence(MethodCallExpression call, Type type)
{
if (ReflectionUtil.IsSequenceSelectMethod(call.Method))
{
MethodCallExpression expression = ResourceBinder.StripTo <MethodCallExpression>(call.Arguments[0]);
if ((expression != null) && ReflectionUtil.IsSequenceSelectMethod(expression.Method))
{
throw new NotSupportedException(System.Data.Services.Client.Strings.ALinq_ExpressionNotSupportedInProjection(type, call.ToString()));
}
}
}
internal static void CheckChainedSequence(MethodCallExpression call, Type type)
{
if (ReflectionUtil.IsSequenceMethod(call.Method, SequenceMethod.Select))
{
MethodCallExpression methodCallExpression = ResourceBinder.StripTo <MethodCallExpression>(call.Arguments[0]);
if (methodCallExpression != null && ReflectionUtil.IsSequenceMethod(methodCallExpression.Method, SequenceMethod.Select))
{
throw new NotSupportedException(string.Format(CultureInfo.CurrentCulture, "Constructing or initializing instances of the type {0} with the expression {1} is not supported.", type, call.ToString()));
}
}
}
internal static void CheckChainedSequence(MethodCallExpression call, Type type)
{
if (ReflectionUtil.IsSequenceMethod(call.Method, SequenceMethod.Select))
{
MethodCallExpression insideCall = ResourceBinder.StripTo <MethodCallExpression>(call.Arguments[0]);
if (insideCall != null && ReflectionUtil.IsSequenceMethod(insideCall.Method, SequenceMethod.Select))
{
throw new NotSupportedException(Strings.ALinq_ExpressionNotSupportedInProjection(type, call.ToString()));
}
}
}
internal override Expression VisitMemberAccess(MemberExpression m)
{
Type type;
Expression expression = base.VisitMemberAccess(m);
Expression item = ResourceBinder.StripTo <Expression>(m.Expression, out type);
if (this.pathFromEntity.Contains(item))
{
this.pathFromEntity.Add(m);
}
return(expression);
}
/// <summary>Initializes a new <see cref="ProjectionPathSegment"/> instance.</summary>
/// <param name="startPath">Path on which this segment is located.</param>
/// <param name="memberExpression">Member expression for the projection path; possibly null.</param>
internal ProjectionPathSegment(ProjectionPath startPath, MemberExpression memberExpression)
{
Debug.Assert(startPath != null, "startPath != null");
Debug.Assert(memberExpression != null, "memberExpression != null");
this.StartPath = startPath;
Expression source = ResourceBinder.StripTo <Expression>(memberExpression.Expression);
this.Member = ClientTypeUtil.GetServerDefinedName(memberExpression.Member);
this.ProjectionType = memberExpression.Type;
this.SourceTypeAs = source.NodeType == ExpressionType.TypeAs ? source.Type : null;
}
/// <summary>
/// Visits a member access expression in non-entity projections, validating that
/// it's correct and recording the path visit to include in a projection if necessary.
/// </summary>
/// <param name="m">Expression to visit.</param>
/// <returns>The same expression.</returns>
/// <remarks>
/// The projection analyzer runs after funcletization, so a member expression
/// rather than a constant expression implies that this is correlated to
/// a parameter, by dotting through the argument in valid cases, and possibly
/// more complex cases in others like new DSC(p.Orders)*.Foo* <- .Foo is invalid.
/// </remarks>
internal override Expression VisitMemberAccess(MemberExpression m)
{
Debug.Assert(m != null, "m != null");
Type expressionType = m.Expression.Type;
this.leafExpressionIsMemberAccess = true;
// if primitive or nullable primitive, allow member access... i.e. calling Value on nullable<int>
if (PrimitiveType.IsKnownNullableType(expressionType))
{
this.leafExpressionIsMemberAccess = false;
return(base.VisitMemberAccess(m));
}
// Only allowed to project entities, also it is ok to do client side projections on complex types.
// Details on the fix for the Dev11 bug 350541 "Inconsistency between Count() method call and Count property projection on clr type collections":
// Relax check to only throw if IsCollectionProducingExpression returns true.
// This enables client side projections (for example "Count") on Clr type collections, like ReadOnlyCollection (which is used in spatial types), ICollection, IList, etc.
// We already allow client side method calls (like Linq extension method "Count()") on clr type collections, so it makes client side projections consistent.
// Note: it will still throw for List<T> (because IsCollectionProducingExpression returns true for List<T>),
// however this is consistent with how we handle MethodCallExpression on clr type collections
// and changing IsCollectionProducingExpression seems risky at this point as it's used in a lot of places.
if (IsCollectionProducingExpression(m.Expression))
{
throw new NotSupportedException(Strings.ALinq_ExpressionNotSupportedInProjection(this.type, m.ToString()));
}
PropertyInfo pi;
Expression boundTarget;
if (ResourceBinder.PatternRules.MatchNonPrivateReadableProperty(m, out pi, out boundTarget))
{
Expression e = base.VisitMemberAccess(m);
if (ClientTypeUtil.TypeOrElementTypeIsEntity(expressionType))
{
Type convertedType;
ResourceBinder.StripTo <Expression>(m.Expression, out convertedType);
this.builder.AppendPropertyToPath(pi, convertedType, this.context);
this.leafExpressionIsMemberAccess = false;
}
return(e);
}
throw new NotSupportedException(Strings.ALinq_ExpressionNotSupportedInProjection(this.type, m.ToString()));
}
/// <summary>Visits a member access expression.</summary>
/// <param name="m">Access to visit.</param>
/// <returns>The same expression.</returns>
internal override Expression VisitMemberAccess(MemberExpression m)
{
Expression result = base.VisitMemberAccess(m);
// Remove any unnecessary type conversions before checking to see if this expression is in the path.
// For this purpose we should consider an expression to be equal to that same expression with an unnecessary conversion.
// E.g. (p as Person) is the same as just p
Type convertedType;
Expression strippedExp = ResourceBinder.StripTo <Expression>(m.Expression, out convertedType);
if (this.pathFromEntity.Contains(strippedExp))
{
this.pathFromEntity.Add(m);
}
return(result);
}
/// <summary>
/// Converts expression to Uri
/// </summary>
/// <param name="e">The expression</param>
/// <returns>Converted uri</returns>
public virtual Uri Convert(Expression e)
{
Uri uri;
Dictionary <Expression, Expression> rewrites = null;
if (!(e is ResourceSetExpression))
{
rewrites = new Dictionary <Expression, Expression>(ReferenceEqualityComparer <Expression> .Instance);
e = Evaluator.PartialEval(e);
e = ExpressionNormalizer.Normalize(e, rewrites);
e = ResourceBinder.Bind(e);
}
UriWriter.Translate(false, e, out uri);
return(uri);
}
internal QueryComponents Translate(Expression e)
{
Uri uri;
Version version;
bool addTrailingParens = false;
Dictionary <Expression, Expression> rewrites = null;
if (!(e is ResourceSetExpression))
{
rewrites = new Dictionary <Expression, Expression>(ReferenceEqualityComparer <Expression> .Instance);
e = Evaluator.PartialEval(e);
e = ExpressionNormalizer.Normalize(e, rewrites);
e = ResourceBinder.Bind(e, this.Context);
addTrailingParens = true;
}
UriWriter.Translate(this.Context, addTrailingParens, e, out uri, out version);
ResourceExpression expression = e as ResourceExpression;
Type lastSegmentType = (expression.Projection == null) ? expression.ResourceType : expression.Projection.Selector.Parameters[0].Type;
return(new QueryComponents(uri, version, lastSegmentType, (expression.Projection == null) ? null : expression.Projection.Selector, rewrites));
}
internal Expression GetRewrite(Expression expression)
{
List <string> list = new List <string>();
expression = ResourceBinder.StripTo <Expression>(expression);
while ((expression.NodeType == ExpressionType.MemberAccess) || (expression.NodeType == ExpressionType.TypeAs))
{
if (expression.NodeType == ExpressionType.MemberAccess)
{
MemberExpression expression2 = (MemberExpression)expression;
list.Add(expression2.Member.Name);
expression = ResourceBinder.StripTo <Expression>(expression2.Expression);
}
else
{
expression = ResourceBinder.StripTo <Expression>(((UnaryExpression)expression).Operand);
}
}
foreach (MemberInitRewrite rewrite in this.rewrites)
{
if ((rewrite.Root != expression) || (list.Count != rewrite.MemberNames.Length))
{
continue;
}
bool flag = true;
for (int i = 0; (i < list.Count) && (i < rewrite.MemberNames.Length); i++)
{
if (list[(list.Count - i) - 1] != rewrite.MemberNames[i])
{
flag = false;
break;
}
}
if (flag)
{
return(rewrite.RewriteExpression);
}
}
return(null);
}
internal ExecutionInfo Bind()
{
ExecutionInfo retVal = new ExecutionInfo();
// IQueryable impl
if (this.Expression != null)
{
Dictionary <Expression, Expression> normalizerRewrites = new Dictionary <Expression, Expression>(ReferenceEqualityComparer <Expression> .Instance);
// Step 1. Evaluate any local evaluatable expressions ( lambdas etc)
Expression partialEvaluatedExpression = Evaluator.PartialEval(this.Expression);
// Step 2. Normalize expression, replace String Comparisons etc.
Expression normalizedExpression = ExpressionNormalizer.Normalize(partialEvaluatedExpression, normalizerRewrites);
// Step 3. Bind Expression, Analyze predicates and create query option expressions. End result is a single ResourceSetExpression
Expression boundExpression = ResourceBinder.Bind(normalizedExpression);
// Step 4. Parse the Bound expression into sub components, i.e. take count, filter, select columns, request options, opcontext, etc.
ExpressionParser parser = new ExpressionParser();
parser.Translate(boundExpression);
// Step 5. Store query components & params
this.TakeCount = parser.TakeCount;
this.FilterString = parser.FilterString;
this.SelectColumns = parser.SelectColumns;
retVal.RequestOptions = parser.RequestOptions;
retVal.OperationContext = parser.OperationContext;
// Step 6. If projection & no resolver then generate a resolver to perform the projection
if (parser.Resolver == null)
{
if (parser.Projection != null && parser.Projection.Selector != ProjectionQueryOptionExpression.DefaultLambda)
{
Type intermediateType = parser.Projection.Selector.Parameters[0].Type;
// Convert Expression to take type object as input to allow for direct invocation.
ParameterExpression paramExpr = Expression.Parameter(typeof(object));
Func <object, TElement> projectorFunc = Expression.Lambda <Func <object, TElement> >(
Expression.Invoke(parser.Projection.Selector, Expression.Convert(paramExpr, intermediateType)), paramExpr).Compile();
// Generate a resolver to do the projection.
retVal.Resolver = (pk, rk, ts, props, etag) =>
{
// Parse to intermediate type
ITableEntity intermediateObject = (ITableEntity)EntityUtilities.InstantiateEntityFromType(intermediateType);
intermediateObject.PartitionKey = pk;
intermediateObject.RowKey = rk;
intermediateObject.Timestamp = ts;
intermediateObject.ReadEntity(props, parser.OperationContext);
intermediateObject.ETag = etag;
// Invoke lambda expression
return(projectorFunc(intermediateObject));
};
}
else
{
// No op - No resolver or projection specified.
}
}
else
{
retVal.Resolver = (EntityResolver <TElement>)parser.Resolver.Value;
}
}
retVal.RequestOptions = TableRequestOptions.ApplyDefaults(retVal.RequestOptions, this.queryProvider.Table.ServiceClient);
retVal.OperationContext = retVal.OperationContext ?? new OperationContext();
return(retVal);
}
/// <summary>
/// Rebinds a conditional that performs a null check on an entity.
/// </summary>
/// <param name="conditional">Conditional expression.</param>
/// <param name="nullCheck">Results of null check analysis.</param>
/// <returns>The rebound expression.</returns>
/// <remarks>
/// Do a rewrite to avoid creating a type in the null check:
/// a.b == null ? null : [a.b]-based expression
/// becomes
/// ProjectionIsNull(a.b) ? null : [a.b]-based expression
/// </remarks>
private Expression RebindConditionalNullCheck(ConditionalExpression conditional, ResourceBinder.PatternRules.MatchNullCheckResult nullCheck)
{
Debug.Assert(conditional != null, "conditional != null");
Debug.Assert(nullCheck.Match, "nullCheck.Match -- otherwise no reason to call this rebind method");
Expression testToNullForProjection = this.Visit(nullCheck.TestToNullExpression);
Expression assignForProjection = this.Visit(nullCheck.AssignExpression);
ExpressionAnnotation testToNullAnnotation;
if (!this.annotations.TryGetValue(testToNullForProjection, out testToNullAnnotation))
{
return base.VisitConditional(conditional);
}
ProjectionPathSegment testToNullSegment = testToNullAnnotation.Segment;
Expression testToNullThroughMethod = this.CallCheckValueForPathIsNull(
testToNullSegment.StartPath.RootEntry,
testToNullSegment.StartPath.ExpectedRootType,
testToNullSegment.StartPath);
Expression test = testToNullThroughMethod;
Expression iftrue = Expression.Constant(null, assignForProjection.Type);
Expression iffalse = assignForProjection;
Expression result = Expression.Condition(test, iftrue, iffalse);
return result;
}
private Expression RebindConditionalNullCheck(ConditionalExpression conditional, ResourceBinder.PatternRules.MatchNullCheckResult nullCheck)
{
ExpressionAnnotation annotation;
Expression key = this.Visit(nullCheck.TestToNullExpression);
Expression expression2 = this.Visit(nullCheck.AssignExpression);
if (!this.annotations.TryGetValue(key, out annotation))
{
return base.VisitConditional(conditional);
}
ProjectionPathSegment segment = annotation.Segment;
Expression test = this.CallCheckValueForPathIsNull(segment.StartPath.RootEntry, segment.StartPath.ExpectedRootType, segment.StartPath);
Expression ifTrue = Expression.Constant(null, expression2.Type);
Expression ifFalse = expression2;
return Expression.Condition(test, ifTrue, ifFalse);
}