internal override Expression Visit(Expression expr)
{
if (expr == null)
{
return(expr);
}
if (DryadLinqExpression.IsConstant(expr))
{
object val = ExpressionSimplifier.Evaluate(expr);
if (val is IQueryable)
{
QueryNodeInfo nodeInfo;
if (this.m_referencedQueryMap.TryGetValue(((IQueryable)val).Expression, out nodeInfo) &&
nodeInfo.QueryNode != null)
{
string name = "side__" + this.m_idx;
this.m_idx++;
ParameterExpression paramExpr = Expression.Parameter(expr.Type, name);
this.m_referencedQueries.Add(new Pair <ParameterExpression, DLinqQueryNode>(paramExpr, nodeInfo.QueryNode));
return(paramExpr);
}
throw new DryadLinqException(DryadLinqErrorCode.UnhandledQuery,
String.Format(SR.UnhandledQuery, DryadLinqExpression.Summarize(expr)));
}
return(expr);
}
return(base.Visit(expr));
}
/// <summary>
/// Creates an instance of DryadLinqException.
/// </summary>
/// <param name="errorCode">The error code.</param>
/// <param name="msg">The error message.</param>
/// <param name="expr">The current expression.</param>
/// <returns></returns>
internal static Exception Create(int errorCode, string msg, Expression expr)
{
StringBuilder sb = new StringBuilder();
sb.Append(msg);
sb.Append(" Expression : ");
sb.AppendLine(DryadLinqExpression.Summarize(expr, 1));
return(new DryadLinqException(errorCode, sb.ToString()));
}
// This is the IQueryProvider.Execute() method used for execution
// when a single value is produced (rather than an enumerable)
public override TResult Execute <TResult>(Expression expression)
{
MethodCallExpression callExpr = expression as MethodCallExpression;
if (callExpr == null)
{
throw new ArgumentException(String.Format(SR.ExpressionMustBeMethodCall,
DryadLinqExpression.Summarize(expression)),
"expression");
}
string methodName = callExpr.Method.Name;
if (methodName == "FirstOrDefault" ||
methodName == "SingleOrDefault" ||
methodName == "LastOrDefault")
{
Type elemType = typeof(AggregateValue <>).MakeGenericType(expression.Type);
Type qType = typeof(DryadLinqQuery <>).MakeGenericType(elemType);
AggregateValue <TResult> res = ((IEnumerable <AggregateValue <TResult> >)
Activator.CreateInstance(
qType,
BindingFlags.NonPublic | BindingFlags.Instance,
null,
new object[] { this, expression },
CultureInfo.CurrentCulture
)).Single();
if (res.Count == 0)
{
return(default(TResult));
}
return(res.Value);
}
else
{
Type qType = typeof(DryadLinqQuery <>).MakeGenericType(expression.Type);
return(((IEnumerable <TResult>)Activator.CreateInstance(
qType,
BindingFlags.NonPublic | BindingFlags.Instance,
null,
new object[] { this, expression },
CultureInfo.CurrentCulture
)).Single());
}
}
/// <summary>
/// Explain one query node.
/// </summary>
/// <param name="plan">Return plan here.</param>
/// <param name="n">Node to explain.</param>
internal static void ExplainNode(StringBuilder plan, DLinqQueryNode n)
{
if (n is DLinqTeeNode || n is DLinqOutputNode ||
n is DLinqDoWhileNode || n is DLinqDummyNode)
{
return;
}
else if (n is DLinqInputNode)
{
plan.AppendLine("Input:");
plan.Append("\t");
n.BuildString(plan);
plan.AppendLine();
return;
}
plan.Append(n.m_vertexEntryMethod);
plan.AppendLine(":");
HashSet <DLinqQueryNode> allchildren = new HashSet <DLinqQueryNode>();
if (n is DLinqSuperNode)
{
DLinqSuperNode sn = n as DLinqSuperNode;
List <DLinqQueryNode> tovisit = new List <DLinqQueryNode>();
tovisit.Add(sn.RootNode);
while (tovisit.Count > 0)
{
DLinqQueryNode t = tovisit[0];
tovisit.RemoveAt(0);
if (!(t is DLinqSuperNode))
{
allchildren.Add(t);
}
foreach (DLinqQueryNode tc in t.Children)
{
if (!allchildren.Contains(tc) && sn.Contains(tc))
{
tovisit.Add(tc);
}
}
}
}
else
{
allchildren.Add(n);
}
foreach (DLinqQueryNode nc in allchildren.Reverse())
{
Expression expression = null; // expression to print
List <string> additional = new List <string>(); // additional arguments to print
int argsToSkip = 0;
string methodname = nc.OpName;
plan.Append("\t");
if (nc is DLinqMergeNode)
{
expression = ((DLinqMergeNode)nc).ComparerExpression;
}
else if (nc is DLinqHashPartitionNode)
{
DLinqHashPartitionNode hp = (DLinqHashPartitionNode)nc;
expression = hp.KeySelectExpression;
additional.Add(hp.NumberOfPartitions.ToString());
}
else if (nc is DLinqGroupByNode)
{
DLinqGroupByNode gb = (DLinqGroupByNode)nc;
expression = gb.KeySelectExpression;
if (gb.ElemSelectExpression != null)
{
additional.Add(DryadLinqExpression.Summarize(gb.ElemSelectExpression));
}
if (gb.ResSelectExpression != null)
{
additional.Add(DryadLinqExpression.Summarize(gb.ResSelectExpression));
}
if (gb.ComparerExpression != null)
{
additional.Add(DryadLinqExpression.Summarize(gb.ComparerExpression));
}
if (gb.SeedExpression != null)
{
additional.Add(DryadLinqExpression.Summarize(gb.SeedExpression));
}
if (gb.AccumulatorExpression != null)
{
additional.Add(DryadLinqExpression.Summarize(gb.AccumulatorExpression));
}
}
else if (nc is DLinqOrderByNode)
{
DLinqOrderByNode ob = (DLinqOrderByNode)nc;
expression = ob.KeySelectExpression;
if (ob.ComparerExpression != null)
{
additional.Add(DryadLinqExpression.Summarize(ob.ComparerExpression));
}
}
else if (nc is DLinqWhereNode)
{
expression = ((DLinqWhereNode)nc).WhereExpression;
}
else if (nc is DLinqSelectNode)
{
DLinqSelectNode s = (DLinqSelectNode)nc;
expression = s.SelectExpression;
if (s.ResultSelectExpression != null)
{
additional.Add(DryadLinqExpression.Summarize(s.ResultSelectExpression));
}
}
else if (nc is DLinqAggregateNode)
{
DLinqAggregateNode a = (DLinqAggregateNode)nc;
expression = a.FuncLambda;
if (a.SeedExpression != null)
{
additional.Add(DryadLinqExpression.Summarize(a.SeedExpression));
}
if (a.ResultLambda != null)
{
additional.Add(DryadLinqExpression.Summarize(a.ResultLambda));
}
}
else if (nc is DLinqPartitionOpNode)
{
expression = ((DLinqPartitionOpNode)nc).ControlExpression;
}
else if (nc is DLinqJoinNode)
{
DLinqJoinNode j = (DLinqJoinNode)nc;
expression = j.OuterKeySelectorExpression;
additional.Add(DryadLinqExpression.Summarize(j.InnerKeySelectorExpression));
additional.Add(DryadLinqExpression.Summarize(j.ResultSelectorExpression));
if (j.ComparerExpression != null)
{
additional.Add(DryadLinqExpression.Summarize(j.ComparerExpression));
}
}
else if (nc is DLinqDistinctNode)
{
expression = ((DLinqDistinctNode)nc).ComparerExpression;
}
else if (nc is DLinqContainsNode)
{
DLinqContainsNode c = (DLinqContainsNode)nc;
expression = c.ValueExpression;
if (c.ComparerExpression != null)
{
additional.Add(DryadLinqExpression.Summarize(c.ComparerExpression));
}
}
else if (nc is DLinqBasicAggregateNode)
{
expression = ((DLinqBasicAggregateNode)nc).SelectExpression;
}
else if (nc is DLinqConcatNode)
// nothing to do
{
}
else if (nc is DLinqSetOperationNode)
{
expression = ((DLinqSetOperationNode)nc).ComparerExpression;
}
else if (nc is DLinqRangePartitionNode)
{
DLinqRangePartitionNode r = (DLinqRangePartitionNode)nc;
expression = r.CountExpression;
// TODO: there's some other possible interesting info
}
else if (nc is DLinqApplyNode)
{
expression = ((DLinqApplyNode)nc).LambdaExpression;
}
else if (nc is DLinqForkNode)
{
expression = ((DLinqForkNode)nc).ForkLambda;
}
else if (nc is DLinqTeeNode)
{
// nothing
}
else if (nc is DLinqDynamicNode)
{
// nothing
}
else
{
expression = nc.QueryExpression;
}
if (expression is MethodCallExpression)
{
MethodCallExpression mc = (MethodCallExpression)expression;
methodname = mc.Method.Name; // overwrite methodname
// determine which arguments to skip
#region LINQMETHODS
switch (mc.Method.Name)
{
case "Aggregate":
case "AggregateAsQuery":
case "Select":
case "LongSelect":
case "SelectMany":
case "LongSelectMany":
case "OfType":
case "Where":
case "LongWhere":
case "First":
case "FirstOrDefault":
case "FirstAsQuery":
case "Single":
case "SingleOrDefault":
case "SingleAsQuery":
case "Last":
case "LastOrDefault":
case "LastAsQuery":
case "Distinct":
case "Any":
case "AnyAsQuery":
case "All":
case "AllAsQuery":
case "Count":
case "CountAsQuery":
case "LongCount":
case "LongCountAsQuery":
case "Sum":
case "SumAsQuery":
case "Min":
case "MinAsQuery":
case "Max":
case "MaxAsQuery":
case "Average":
case "AverageAsQuery":
case "GroupBy":
case "OrderBy":
case "OrderByDescending":
case "ThenBy":
case "ThenByDescending":
case "Take":
case "TakeWhile":
case "LongTakeWhile":
case "Skip":
case "SkipWhile":
case "LongSkipWhile":
case "Contains":
case "ContainsAsQuery":
case "Reverse":
case "Merge":
case "HashPartition":
case "RangePartition":
case "Fork":
case "ForkChoose":
case "AssumeHashPartition":
case "AssumeRangePartition":
case "AssumeOrderBy":
case "ToPartitionedTableLazy":
case "AddCacheEntry":
case "SlidingWindow":
case "ApplyWithPartitionIndex":
case "DoWhile":
argsToSkip = 1;
break;
case "Join":
case "GroupJoin":
case "Concat":
case "MultiConcat":
case "Union":
case "Intersect":
case "Except":
case "SequenceEqual":
case "SequenceEqualAsQuery":
case "Zip":
argsToSkip = 2;
break;
case "Apply":
case "ApplyPerPartition":
if (mc.Arguments.Count < 3)
{
argsToSkip = 1;
}
else
{
argsToSkip = 2;
}
break;
default:
throw DryadLinqException.Create(DryadLinqErrorCode.OperatorNotSupported,
String.Format(SR.OperatorNotSupported, mc.Method.Name),
expression);
}
#endregion
plan.Append(methodname);
plan.Append("(");
int argno = 0;
foreach (var arg in mc.Arguments)
{
argno++;
if (argno <= argsToSkip)
{
continue;
}
if (argno > argsToSkip + 1)
{
plan.Append(",");
}
plan.Append(DryadLinqExpression.Summarize(arg));
}
plan.AppendLine(")");
}
else
{
// expression is not methodcall
plan.Append(methodname);
plan.Append("(");
if (expression != null)
{
plan.Append(DryadLinqExpression.Summarize(expression));
}
foreach (string e in additional)
{
plan.Append(",");
plan.Append(e);
}
plan.AppendLine(")");
}
}
}
