private string OperatorToString(KQLPropertyOperator ops)
{
switch (ops)
{
case KQLPropertyOperator.DoesNoEqual: return("<>");
case KQLPropertyOperator.EqualTo: return("=");
case KQLPropertyOperator.GreaterThanOrEqualTo: return(">=");
case KQLPropertyOperator.GreaterThan: return(">");
case KQLPropertyOperator.LesserThan: return("<");
case KQLPropertyOperator.LesserThanOrEqualTo: return("<=");
case KQLPropertyOperator.Matches: return(":");
case KQLPropertyOperator.Restriction: return("..");
}
return("");
}
/// <summary>
/// Parses a KQL query and returns a list of tokens
/// </summary>
/// <param name="searchQuery">Query to parse</param>
/// <returns>List of <see cref="KQLElement"/> tokens</returns>
public List <KQLElement> Parse(string searchQuery)
{
// See https://docs.microsoft.com/en-us/sharepoint/dev/general-development/keyword-query-language-kql-syntax-reference
List <KQLElement> parsedQuery = new List <KQLElement>(10);
try
{
if (string.IsNullOrEmpty(searchQuery))
{
return(parsedQuery);
}
var parts = searchQuery.Trim().Split(new string[] { " " }, StringSplitOptions.RemoveEmptyEntries);
int group = 0;
bool groupOpen = false;
bool groupToClose = false;
for (int i = 0; i < parts.Length; i++)
{
var part = parts[i];
if (!groupOpen && part.StartsWith("("))
{
group = group + 1;
groupOpen = true;
// Strip the (
part = part.Substring(1);
}
if (groupOpen && part.EndsWith(")"))
{
groupToClose = true;
// Strip the )
part = part.TrimEnd(new char[] { ')' });
}
KQLPropertyOperator op = DetectOperator(part);
if (op != KQLPropertyOperator.Undefined)
{
string opAsString = OperatorToString(op);
KQLElement k = new KQLElement()
{
Type = KQLFilterType.PropertyFilter,
Operator = op,
Group = groupOpen ? group : 0,
Filter = part.Substring(0, part.IndexOf(opAsString)),
Value = part.Substring(part.IndexOf(opAsString) + opAsString.Length)
};
parsedQuery.Add(k);
}
else if (part.StartsWith("{") && part.EndsWith("}"))
{
KQLElement k = new KQLElement()
{
Type = KQLFilterType.KeywordFilter,
Operator = KQLPropertyOperator.Undefined,
Group = groupOpen ? group : 0,
Filter = part.Replace("{", "").Replace("}", ""),
Value = "",
};
parsedQuery.Add(k);
}
else
{
if (part.Equals("OR", StringComparison.InvariantCultureIgnoreCase) ||
part.Equals("AND", StringComparison.InvariantCultureIgnoreCase) ||
part.Equals("NEAR", StringComparison.InvariantCultureIgnoreCase) ||
part.StartsWith("NEAR(", StringComparison.InvariantCultureIgnoreCase) ||
part.Equals("ONENEAR", StringComparison.InvariantCultureIgnoreCase) ||
part.StartsWith("ONENEAR(", StringComparison.InvariantCultureIgnoreCase) ||
part.StartsWith("XRANK(", StringComparison.InvariantCultureIgnoreCase) ||
part.Equals("NOT", StringComparison.InvariantCultureIgnoreCase))
{
// Don't add operators as KQL elements
}
else
{
KQLElement k = new KQLElement()
{
Type = KQLFilterType.Text,
Operator = KQLPropertyOperator.Undefined,
Group = groupOpen ? group : 0,
Filter = "",
Value = part,
};
parsedQuery.Add(k);
}
}
if (groupToClose)
{
groupOpen = false;
groupToClose = false;
}
}
}
catch (Exception ex)
{
// Eat exceptions for now, KQL query parsing will be obsolete when the AdvancedQuery option becomes available
}
return(parsedQuery);
}