/// <summary>
/// Gets the row value for the aggregator as number
/// </summary>
internal Double GetRowValueAsNumber(DataRow tableRow)
{
try
{
if (!tableRow.IsNull(this.AggregatorVariable.VariableName))
{
RDFPatternMember rowAggregatorValue = RDFQueryUtilities.ParseRDFPatternMember(tableRow[this.AggregatorVariable.VariableName].ToString());
//PlainLiteral: accepted only if numeric and non-languaged
if (rowAggregatorValue is RDFPlainLiteral)
{
if (String.IsNullOrEmpty(((RDFPlainLiteral)rowAggregatorValue).Language))
{
if (Double.TryParse(rowAggregatorValue.ToString(), NumberStyles.Float, CultureInfo.InvariantCulture, out Double doubleValue))
{
return(doubleValue);
}
}
}
//TypedLiteral: accepted only if numeric
else if (rowAggregatorValue is RDFTypedLiteral)
{
if (((RDFTypedLiteral)rowAggregatorValue).HasDecimalDatatype())
{
return(Double.Parse(((RDFTypedLiteral)rowAggregatorValue).Value, NumberStyles.Float, CultureInfo.InvariantCulture));
}
}
}
return(Double.NaN);
}
catch (Exception ex)
{
RDFQueryEvents.RaiseSELECTQueryEvaluation(String.Format("Exception intercepted during evaluation of RDFAggregator '{0}' in method GetRowValueAsNumber: '{1}'", this, ex.Message));
return(Double.NaN);
}
}
/// <summary>
/// Applies the query to the given SPARQL endpoint
/// </summary>
public RDFDescribeQueryResult ApplyToSPARQLEndpoint(RDFSPARQLEndpoint sparqlEndpoint)
{
RDFDescribeQueryResult describeResult = new RDFDescribeQueryResult(this.ToString());
if (sparqlEndpoint != null)
{
RDFQueryEvents.RaiseDESCRIBEQueryEvaluation(String.Format("Evaluating DESCRIBE query on SPARQL endpoint '{0}'...", sparqlEndpoint));
//Establish a connection to the given SPARQL endpoint
using (WebClient webClient = new WebClient())
{
//Insert reserved "query" parameter
webClient.QueryString.Add("query", HttpUtility.UrlEncode(this.ToString()));
//Insert user-provided parameters
webClient.QueryString.Add(sparqlEndpoint.QueryParams);
//Insert request headers
webClient.Headers.Add(HttpRequestHeader.Accept, "application/turtle");
webClient.Headers.Add(HttpRequestHeader.Accept, "text/turtle");
//Send querystring to SPARQL endpoint
var sparqlResponse = webClient.DownloadData(sparqlEndpoint.BaseAddress);
//Parse response from SPARQL endpoint
if (sparqlResponse != null)
{
using (var sStream = new MemoryStream(sparqlResponse))
{
describeResult = RDFDescribeQueryResult.FromRDFGraph(RDFGraph.FromStream(RDFModelEnums.RDFFormats.Turtle, sStream));
}
describeResult.DescribeResults.TableName = this.ToString();
}
}
//Eventually adjust column names (should start with "?")
Int32 columnsCount = describeResult.DescribeResults.Columns.Count;
for (Int32 i = 0; i < columnsCount; i++)
{
if (!describeResult.DescribeResults.Columns[i].ColumnName.StartsWith("?"))
{
describeResult.DescribeResults.Columns[i].ColumnName = "?" + describeResult.DescribeResults.Columns[i].ColumnName;
}
}
RDFQueryEvents.RaiseDESCRIBEQueryEvaluation(String.Format("Evaluated DESCRIBE query on SPARQL endpoint '{0}': Found '{1}' results.", sparqlEndpoint, describeResult.DescribeResultsCount));
}
return(describeResult);
}
/// <summary>
/// Applies the query to the given SPARQL endpoint
/// </summary>
public RDFSelectQueryResult ApplyToSPARQLEndpoint(RDFSPARQLEndpoint sparqlEndpoint)
{
RDFSelectQueryResult selResult = new RDFSelectQueryResult();
if (sparqlEndpoint != null)
{
RDFQueryEvents.RaiseSELECTQueryEvaluation(String.Format("Evaluating SELECT query on SPARQL endpoint '{0}'...", sparqlEndpoint));
//Establish a connection to the given SPARQL endpoint
using (WebClient webClient = new WebClient())
{
//Insert reserved "query" parameter
webClient.QueryString.Add("query", HttpUtility.UrlEncode(this.ToString()));
//Insert user-provided parameters
webClient.QueryString.Add(sparqlEndpoint.QueryParams);
//Insert request headers
webClient.Headers.Add(HttpRequestHeader.Accept, "application/sparql-results+xml");
//Send querystring to SPARQL endpoint
var sparqlResponse = webClient.DownloadData(sparqlEndpoint.BaseAddress);
//Parse response from SPARQL endpoint
if (sparqlResponse != null)
{
using (var sStream = new MemoryStream(sparqlResponse))
{
selResult = RDFSelectQueryResult.FromSparqlXmlResult(sStream);
}
selResult.SelectResults.TableName = this.ToString();
}
}
//Eventually adjust column names (should start with "?")
Int32 columnsCount = selResult.SelectResults.Columns.Count;
for (Int32 i = 0; i < columnsCount; i++)
{
if (!selResult.SelectResults.Columns[i].ColumnName.StartsWith("?"))
{
selResult.SelectResults.Columns[i].ColumnName = "?" + selResult.SelectResults.Columns[i].ColumnName;
}
}
RDFQueryEvents.RaiseSELECTQueryEvaluation(String.Format("Evaluated SELECT query on SPARQL endpoint '{0}': Found '{1}' results.", sparqlEndpoint, selResult.SelectResultsCount));
}
return(selResult);
}
/// <summary>
/// Gets the row value for the aggregator as string
/// </summary>
internal String GetRowValueAsString(DataRow tableRow)
{
try
{
if (!tableRow.IsNull(this.AggregatorVariable.VariableName))
{
return(tableRow[this.AggregatorVariable.VariableName].ToString());
}
return(String.Empty);
}
catch (Exception ex)
{
RDFQueryEvents.RaiseSELECTQueryEvaluation(String.Format("Exception intercepted during evaluation of RDFAggregator '{0}' in method GetRowValueAsString: '{1}'", this, ex.Message));
return(String.Empty);
}
}
/// <summary>
/// Adds the given alternative steps to the path. If only one is given, it is considered sequence.
/// </summary>
public RDFPropertyPath AddAlternativeSteps(List <RDFPropertyPathStep> alternativeSteps)
{
if (alternativeSteps != null && alternativeSteps.Any())
{
#region Depth Guard
if (this.Steps.Count == 0 ||
alternativeSteps.Count == 1 ||
this.Steps.LastOrDefault()?.StepFlavor == RDFQueryEnums.RDFPropertyPathStepFlavors.Sequence)
{
this.Depth++;
}
#endregion
#region Steps Update
if (alternativeSteps.Count == 1)
{
this.Steps.Add(alternativeSteps[0].SetOrdinal(this.Steps.Count)
.SetFlavor(RDFQueryEnums.RDFPropertyPathStepFlavors.Sequence));
}
else
{
alternativeSteps.ForEach(alternativeStep =>
{
this.Steps.Add(alternativeStep.SetOrdinal(this.Steps.Count)
.SetFlavor(RDFQueryEnums.RDFPropertyPathStepFlavors.Alternative));
});
}
#endregion
#region Evaluability Guard
if (this.Start is RDFVariable || this.End is RDFVariable || this.Depth > 1)
{
this.IsEvaluable = true;
RDFQueryEvents.RaiseGENERICQueryEvaluation("AddAlternativeSteps: non-ground property path detected, evaluability granted or confirmed.");
}
else
{
RDFQueryEvents.RaiseGENERICQueryEvaluation("AddAlternativeSteps: ground property path detected, evaluability not granted.");
}
#endregion
}
return(this);
}
/// <summary>
/// Applies the query to the given SPARQL endpoint
/// </summary>
public RDFConstructQueryResult ApplyToSPARQLEndpoint(RDFSPARQLEndpoint sparqlEndpoint)
{
RDFConstructQueryResult constructResult = new RDFConstructQueryResult(this.ToString());
if (sparqlEndpoint != null)
{
RDFQueryEvents.RaiseCONSTRUCTQueryEvaluation(String.Format("Evaluating CONSTRUCT query on SPARQL endpoint '{0}'...", sparqlEndpoint));
//Establish a connection to the given SPARQL endpoint
using (WebClient webClient = new WebClient())
{
//Insert reserved "query" parameter
webClient.QueryString.Add("query", HttpUtility.UrlEncode(this.ToString()));
//Insert user-provided parameters
webClient.QueryString.Add(sparqlEndpoint.QueryParams);
//Insert request headers
webClient.Headers.Add(HttpRequestHeader.Accept, "application/turtle");
webClient.Headers.Add(HttpRequestHeader.Accept, "text/turtle");
//Send querystring to SPARQL endpoint
var sparqlResponse = webClient.DownloadData(sparqlEndpoint.BaseAddress);
//Parse response from SPARQL endpoint
if (sparqlResponse != null)
{
using (var sStream = new MemoryStream(sparqlResponse))
{
constructResult = RDFConstructQueryResult.FromRDFGraph(RDFGraph.FromStream(RDFModelEnums.RDFFormats.Turtle, sStream));
}
constructResult.ConstructResults.TableName = this.ToString();
}
}
RDFQueryEvents.RaiseCONSTRUCTQueryEvaluation(String.Format("Evaluated CONSTRUCT query on SPARQL endpoint '{0}': Found '{1}' results.", sparqlEndpoint, constructResult.ConstructResultsCount));
}
return(constructResult);
}
/// <summary>
/// Applies the query to the given SPARQL endpoint
/// </summary>
public RDFAskQueryResult ApplyToSPARQLEndpoint(RDFSPARQLEndpoint sparqlEndpoint)
{
RDFAskQueryResult askResult = new RDFAskQueryResult();
if (sparqlEndpoint != null)
{
RDFQueryEvents.RaiseASKQueryEvaluation(String.Format("Evaluating ASK query on SPARQL endpoint '{0}'...", sparqlEndpoint));
//Establish a connection to the given SPARQL endpoint
using (WebClient webClient = new WebClient())
{
//Insert reserved "query" parameter
webClient.QueryString.Add("query", HttpUtility.UrlEncode(this.ToString()));
//Insert user-provided parameters
webClient.QueryString.Add(sparqlEndpoint.QueryParams);
//Insert request headers
webClient.Headers.Add(HttpRequestHeader.Accept, "application/sparql-results+xml");
//Send querystring to SPARQL endpoint
var sparqlResponse = webClient.DownloadData(sparqlEndpoint.BaseAddress);
//Parse response from SPARQL endpoint
if (sparqlResponse != null)
{
using (var sStream = new MemoryStream(sparqlResponse))
{
askResult = RDFAskQueryResult.FromSparqlXmlResult(sStream);
}
}
}
RDFQueryEvents.RaiseASKQueryEvaluation(String.Format("Evaluated ASK query on SPARQL endpoint '{0}': Result is '{1}'.", sparqlEndpoint, askResult.AskResult));
}
return(askResult);
}
/// <summary>
/// Adds the given sequence step to the path
/// </summary>
public RDFPropertyPath AddSequenceStep(RDFPropertyPathStep sequenceStep)
{
if (sequenceStep != null)
{
#region Steps Update
this.Depth++;
this.Steps.Add(sequenceStep.SetOrdinal(this.Steps.Count)
.SetFlavor(RDFQueryEnums.RDFPropertyPathStepFlavors.Sequence));
#endregion
#region Evaluability Guard
if (this.Start is RDFVariable || this.End is RDFVariable || this.Depth > 1)
{
this.IsEvaluable = true;
RDFQueryEvents.RaiseGENERICQueryEvaluation("AddSequenceStep: non-ground property path detected, evaluability granted or confirmed.");
}
else
{
RDFQueryEvents.RaiseGENERICQueryEvaluation("AddSequenceStep: ground property path detected, evaluability not granted.");
}
#endregion
}
return(this);
}
