internal static FanoutSearchModule GetClientModule()
{
FanoutSearchModule ret = new FanoutSearchModule();
ret.ClientInitialize(RunningMode.Server);
return(ret);
}
/// <returns>null if no cached query result is found.</returns>
internal AggregationObject GetCachedQueryResult(FanoutQueryMessageReader query)
{
string key = GetQueryResultCacheRequestKey(query);
QueryResultCacheEntry entry = (QueryResultCacheEntry)m_memory_cache.Get(key);
if (entry == null)
{
return(null);
}
int result_cnt = entry.aggregation_obj.results.Count;
if (result_cnt < FanoutSearchModule.MinimalRequiredResultCount(query))
{
return(null);
}
Log.WriteLine(LogLevel.Debug, "QueryResultCache: Cache hit.");
return(entry.aggregation_obj);
}
private static Expression <Func <ICellAccessor, Action> > ConstructVisitNodeAction(ExpressionSyntax traverseAction)
{
/***********************************************
* Syntax: (VISITNODE)
*
* 1. VisitNode(FanoutSearch.Action action, IEnumerable<string> select = null)
* 2. VisitNode(Expression<Func<ICellAccessor, FanoutSearch.Action>> action, IEnumerable<string> select = null)
*
* The select part is handled by the caller.
***********************************************/
var action_expr = TryGet <MemberAccessExpressionSyntax>(traverseAction);
var lambda_expression = TryGet <LambdaExpressionSyntax>(traverseAction);
Expression <Func <ICellAccessor, Action> > ret = null;
if (action_expr != null)
{
// Action enum
var id_expr = Get <IdentifierNameSyntax>(action_expr.Expression);
if (id_expr.ToString() != s_LIKQ_Action)
{
goto throw_badtype;
}
Action result_action;
ThrowIf(!Enum.TryParse(action_expr.Name.ToString(), out result_action), "Invalid traverse action", action_expr);
return(ExpressionBuilder.WrapAction(result_action));
}
else
{
if (lambda_expression == null)
{
goto throw_badtype;
}
// FanoutSearch.Action is ambiguous with with System.Action
var action_visitor = new FanoutSearchActionRewritter();
lambda_expression = action_visitor.Visit(lambda_expression) as LambdaExpressionSyntax;
ScriptOptions scriptOptions = ScriptOptions.Default;
var mscorlib = typeof(System.Object).Assembly;
var systemCore = typeof(System.Linq.Enumerable).Assembly;
var expression = typeof(Expression).Assembly;
var fanout = typeof(FanoutSearchModule).Assembly;
var trinity = typeof(Trinity.Global).Assembly;
scriptOptions = scriptOptions.AddReferences(mscorlib, systemCore, expression, fanout, trinity);
scriptOptions = scriptOptions.AddImports(
"System",
"System.Linq",
"System.Linq.Expressions",
"System.Collections.Generic",
"FanoutSearch",
"FanoutSearch.LIKQ",
"Trinity",
"Trinity.Storage");
try
{
// Allocate a cancellation token source, which signals after our timeout setting (if we do have timeout setting)
CancellationToken cancel_token = default(CancellationToken);
if (FanoutSearchModule._QueryTimeoutEnabled())
{
checked
{
cancel_token = new CancellationTokenSource((int)FanoutSearchModule.GetQueryTimeout()).Token;
}
}
// It is guaranteed that the lambda_expression is really a lambda.
// Evaluating a lambda and expecting an expression tree to be obtained now.
using (var eval_task = CSharpScript.EvaluateAsync <Expression <Func <ICellAccessor, Action> > >(lambda_expression.ToString(), scriptOptions, cancellationToken: cancel_token))
{
eval_task.Wait(cancel_token);
ret = eval_task.Result;
}
}
catch (ArithmeticException) { /* that's a fault not an error */ throw; }
catch { /*swallow roslyn scripting engine exceptions.*/ }
ThrowIf(null == ret, "Invalid lambda expression.", traverseAction);
return(ret);
}
throw_badtype:
ThrowIf(true, "Expecting an argument of type FanoutSearch.Action, or a lambda expression.", traverseAction);
return(null);//not going to happen
}
static MessageDispatcher()
{
s_ServerCount = Global.CloudStorage.ServerCount;
s_Module = Global.CloudStorage.GetCommunicationModule <FanoutSearchModule>();
}
