public async Task <IEnumerable <OpisenseOpcItemValue> > ReadGroup(CancellationToken cancellationToken, string opcServerUrl, OpisenseOpcItemGroup opcItemGroup, Action <IEnumerable <string> > onError = null, bool discardBadValues = true)
{
var opisenseOpcItemsList = opcItemGroup.OpisenseOpcItems.ToList();
var readResult = new List <OpisenseOpcItemValue>(opisenseOpcItemsList.Count);
var errors = new List <string>();
void HandleItemValue(ItemValue itemValue)
{
//There is a bug in the library, ClientHandle is not propagated with item results
//if (!int.TryParse(itemValue.ClientHandle.ToString(), out int variableId))
{
}
try
{
var variableIds = opisenseOpcItemsList.Where(i => i.OpcItemName.Equals(itemValue.ItemName, StringComparison.InvariantCultureIgnoreCase)).Select(i => i.VariableId);
readResult.AddRange(variableIds.Select(variableId => new OpisenseOpcItemValue
{
TimeStampUtc = new DateTime(itemValue.Timestamp.Ticks, DateTimeKind.Local).ToUniversalTime(),
OpcItemName = itemValue.ItemName,
VariableId = variableId,
Value = ResultAsDouble(itemValue),
GoodQuality = itemValue.Quality == Quality.Good
}));
}
catch (Exception ex)
{
var message = $"Exception handling item '{itemValue.ItemName}' with value '{itemValue.Value}': {ex.Message}";
errors.Add(message);
}
}
await OpcDaClientConnector
.WithNewInstance()
.ReadItems(cancellationToken, opcServerUrl, opisenseOpcItemsList,
goodValue =>
{
HandleItemValue(goodValue);
return(Task.FromResult(0));
},
badValue =>
{
if (!discardBadValues)
{
HandleItemValue(badValue);
}
return(Task.FromResult(0));
},
exception => errors.Add(exception.Message));
if (errors.Any())
{
if (onError is null)
{
Logger.Error($"Exception reading items from OPC server {opcServerUrl}: {string.Join(", ", errors)}");
}
else
{
onError(errors);
}
}
return(readResult);
}
public Task PollGroup(CancellationToken cancellationToken, string opcServerUrl, OpisenseOpcItemGroup opcItemGroup, Action <Guid, IList <OpisenseOpcItemValue> > onGroupReadResult, Action <Guid, int> beforeGroupRead = null, Action <Guid, int, DateTime> afterGroupRead = null, Action <Guid, string> onGroupError = null)
{
return(Task.Factory.StartNew(async() =>
{
void HandleErrors(IEnumerable <string> errors)
{
foreach (var error in errors)
{
onGroupError?.Invoke(opcItemGroup.GroupId, error);
}
}
while (!cancellationToken.IsCancellationRequested)
{
try
{
beforeGroupRead?.Invoke(opcItemGroup.GroupId, opcItemGroup.OpisenseOpcItems.Count);
var res = (await ReadGroup(cancellationToken,
opcServerUrl,
opcItemGroup,
HandleErrors)).ToList();
afterGroupRead?.Invoke(opcItemGroup.GroupId, res.Count, DateTime.UtcNow.Add(opcItemGroup.PollingCycle));
onGroupReadResult(opcItemGroup.GroupId, res);
}
catch (Exception)
{
//Stay alive even if the calee fails
}
try
{
await Task.Delay(opcItemGroup.PollingCycle, cancellationToken);
}
catch (TaskCanceledException)
{
break;
}
}
}
, cancellationToken
, TaskCreationOptions.LongRunning
, TaskScheduler.Default));
}
