public static bool IsDonutAggregateFunction(this IExpression expr)
{
if (expr is CallExpression callExpr)
{
var df = new DonutFunctions();
return(df.IsAggregate(callExpr));
}
return(false);
}
public static bool IsDonutNativeFeature(this AssignmentExpression fExpr)
{
var fExpression = fExpr.Value;
if (fExpression is CallExpression callExpr)
{
var df = new DonutFunctions();
if (df.IsAggregate(callExpr))
{
return(false);
}
var fnType = df.GetFunctionType(callExpr);
return(fnType == DonutFunctionType.Donut);
}
return(false);
}
private string GetFeatureYieldsContent(DonutScript script)
{
var fBuilder = new StringBuilder();
var donutFnResolver = new DonutFunctions();
foreach (var feature in script.Features)
{
IExpression accessor = feature.Value;
string fName = feature.Member.ToString();
string featureContent = "";
var featureFType = accessor.GetType();
if (featureFType == typeof(NameExpression))
{
var member = (accessor as NameExpression).Member?.ToString();
//In some cases we might just use the field
if (string.IsNullOrEmpty(member))
{
member = accessor.ToString();
}
featureContent = $"yield return pair(\"{fName}\", doc[\"{member}\"]);";
}
else if (featureFType == typeof(CallExpression))
{
if (donutFnResolver.IsAggregate(accessor as CallExpression))
{
//We're dealing with an aggregate call
//var aggregateContent = GenerateFeatureFunctionCall(accessor as CallExpression, feature);
}
else
{
//We're dealing with a function call
//featureContent = GenerateFeatureFunctionCall(accessor as CallExpression, feature).Content;
}
}
else
{
throw new NotImplementedException();
}
if (!string.IsNullOrEmpty(featureContent))
{
fBuilder.AppendLine(featureContent);
}
}
return(fBuilder.ToString());
}
/// <summary>
///
/// </summary>
/// <param name="callExpression"></param>
/// <param name="feature"></param>
/// <returns></returns>
public FeatureFunctionsCodeResult GenerateFeatureFunctionCall(CallExpression callExpression, AssignmentExpression feature = null)
{
var fnDict = new DonutFunctions();
var isAggregate = fnDict.IsAggregate(callExpression);
var functionType = fnDict.GetFunctionType(callExpression);
Clean();
_expVisitor.Clear();
var strValues = VisitCall(callExpression, null, _expVisitor);
if (string.IsNullOrEmpty(strValues))
{
return(null);
}
if (isAggregate)
{
var aggregateField = new BsonDocument();
if (feature == null)
{
try
{
aggregateField = BsonDocument.Parse(strValues);
}
catch (Exception ex)
{
Trace.WriteLine($"Failed to parse expression: {callExpression}\nError: {ex.Message}");
return(null);
}
}
else
{
aggregateField[feature.Member.ToString()] = BsonDocument.Parse(strValues);
}
var result = new FeatureFunctionsCodeResult(functionType, aggregateField.ToString());
return(result);
}
else
{
return(new FeatureFunctionsCodeResult(strValues));
}
}