/// <summary>
/// Query to subtract the oldest value of a OPC UA node
/// from the newest value in the search span
/// </summary>
/// <param name="searchSpan">Date and time span for the query</param>
/// <param name="appUri">The OPC UA server application Uri</param>
/// <param name="nodeId">The node id in the OPC UA server namespace</param>
/// <returns>The difference</returns>
public async Task <double> DiffQuery(DateTimeRange searchSpan, string appUri, string nodeId)
{
try
{
PredicateStringExpression expression = new PredicateStringExpression(
String.Format(OpcServerNodePredicate, appUri, nodeId));
BaseLimitClause firstMember = new TopLimitClause(1,
new[]
{
new SortClause(new BuiltInPropertyReferenceExpression(BuiltInProperty.Timestamp),
SortOrderType.Asc)
});
BaseLimitClause lastMember = new TopLimitClause(1,
new[]
{
new SortClause(new BuiltInPropertyReferenceExpression(BuiltInProperty.Timestamp),
SortOrderType.Desc)
});
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
Task <IEnumerable <IEvent> > firstTask = RDXQueryClient.GetEventsAsync(
searchSpan,
expression,
firstMember,
_cancellationToken);
Task <IEnumerable <IEvent> > lastTask = RDXQueryClient.GetEventsAsync(
searchSpan,
expression,
lastMember,
_cancellationToken);
await Task.WhenAll(new Task[] { firstTask, lastTask });
IEnumerable <IEvent> firstEvent = firstTask.Result;
IEnumerable <IEvent> lastEvent = lastTask.Result;
stopwatch.Stop();
RDXTrace.TraceInformation("DiffQuery queries took {0} ms", stopwatch.ElapsedMilliseconds);
long first = GetValueOfProperty <long>(firstEvent.First <IEvent>(), OpcMonitoredItemValue);
long last = GetValueOfProperty <long>(lastEvent.First <IEvent>(), OpcMonitoredItemValue);
return(last - first);
}
catch (Exception e)
{
RDXTrace.TraceError("DiffQuery Exception {0}", e.Message);
return(0);
}
}
/// <summary>
/// Helper to query for last event of given station and nodeid
/// </summary>
private Task <IEnumerable <IEvent> > GetLatestEvent(DateTime endTime, string appUri, string nodeId)
{
PredicateStringExpression expression = new PredicateStringExpression(
String.Format(OpcServerNodePredicate, appUri, nodeId));
DateTimeRange searchSpan = new DateTimeRange(endTime.Subtract(TimeSpan.FromDays(360)), endTime);
BaseLimitClause lastMember = new TopLimitClause(1,
new[]
{
new SortClause(new BuiltInPropertyReferenceExpression(BuiltInProperty.Timestamp),
SortOrderType.Desc)
});
return(RDXQueryClient.GetEventsAsync(
searchSpan,
expression,
lastMember,
_cancellationToken));
}
/// <summary>
/// Query for aggregation of count, min, max, sum and average for all active
/// nodes of the given OPC UA server in the given search span as time histogram
/// with interval
/// </summary>
/// <param name="searchSpan">Date and time span for the query</param>
/// <param name="appUri">The OPC UA server application Uri</param>
/// <param name="interval">Interval for Date Time Histogram</param>
/// <returns>The aggregated nodes</returns>
public async Task <AggregateResult> GetAllAggregatedNodesWithInterval(DateTimeRange searchSpan, string appUri, string nodeId, TimeSpan interval)
{
try
{
string id = TimeSpanToId(interval);
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
PredicateStringExpression predicate = new PredicateStringExpression(
String.Format(OpcServerNodePredicate, appUri, nodeId));
Aggregate aggregate = new Aggregate(
Expression.UniqueValues(OpcMonitoredItemId, PropertyType.String, opcMaxMonitoredItemId),
new Aggregate(Expression.DateHistogram(BuiltInProperty.Timestamp, IntervalSize.FromId(id)),
new Aggregate(
Expression.Count(),
Expression.Min(OpcMonitoredItemValue, PropertyType.Double),
Expression.Max(OpcMonitoredItemValue, PropertyType.Double),
Expression.Average(OpcMonitoredItemValue, PropertyType.Double),
Expression.Sum(OpcMonitoredItemValue, PropertyType.Double)
)));
AggregatesResult aggregateResults = await RDXQueryClient.GetAggregatesAsync(
searchSpan,
predicate,
new[] { aggregate },
_cancellationToken);
// Since there was 1 top level aggregate in request, there is 1 aggregate result.
AggregateResult aggregateResult = aggregateResults[0];
stopwatch.Stop();
RDXTrace.TraceInformation("GetAllAggregatedNodes query took {0} ms", stopwatch.ElapsedMilliseconds);
return(aggregateResult);
}
catch (Exception e)
{
RDXTrace.TraceError("GetAllAggregatedNodes: Exception {0}", e.Message);
return(null);
}
}
/// <summary>
/// Query for aggregation of a given measure for the
/// given node and given OPC UA server in the given search span
/// </summary>
/// <param name="searchSpan">Date and time span for the query</param>
/// <param name="appUri">The OPC UA server application Uri</param>
/// <param name="nodeId">The node id in the OPC UA server namespace</param>
/// <param name="measure"></param>
public async Task <double> GetAggregatedNode(DateTimeRange searchSpan, string appUri, string nodeId, AggregateExpression measure)
{
try
{
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
PredicateStringExpression predicate = new PredicateStringExpression(
String.Format(OpcServerNodePredicate, appUri, nodeId));
Aggregate aggregate = new Aggregate(
measures: new AggregateExpression[] { measure }
);
AggregatesResult aggregateResults = await RDXQueryClient.GetAggregatesAsync(
searchSpan,
predicate,
new[] { aggregate },
_cancellationToken);
// Since there was 1 top level aggregate in request, there is 1 aggregate result.
AggregateResult aggregateResult = aggregateResults[0];
stopwatch.Stop();
RDXTrace.TraceInformation("AggregateQuery query took {0} ms", stopwatch.ElapsedMilliseconds);
if (aggregateResult.Measures == null)
{
return(0.00);
}
return((double)aggregateResult.Measures[0]);
}
catch (Exception e)
{
RDXTrace.TraceError("AggregateQuery: Exception {0}", e.Message);
return(0);
}
}