Unsolicited Tags Callbacks

Example

The following sample helps you understand the given callback functions. The below sample code creates a thread for simulating the Unsolicited tag's collector behavior.

//This structure is the list of Unsolicited Tags. 
struct AsyncTagList : public CList<ihInterfaceTKASyncTagInfo*, ihInterfaceTKASyncTagInfo*>
{
virtual ~AsyncTagList()
{
FreeAll();
} 
void AddTag(ihInterfaceTKASyncTagInfo* tag)
{
ihInterfaceTKASyncTagInfo* info = new ihInterfaceTKASyncTagInfo;//need to allocate in delegator
memcpy(info, tag, sizeof(ihInterfaceTKASyncTagInfo));
AddTail(info);
}
void FreeAll()
{
while (!IsEmpty())
delete RemoveHead();
}
}; 
AsyncTagList g_AsyncTags; 
 
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/// <summary>
/// Initializes unsolicited tags, by creating dedicated thread
/// <summary>
/// <returns></returns>
int    RandomValueSimulator::ihCollectorToolkitASyncInit(void)
{
       CSingleLock lock(&g_Sync, TRUE);
       g_AsyncTags.FreeAll();
       if (!g_AsyncThread)
              g_AsyncThread = AfxBeginThread(TKAsyncReadFunc, this);
       return TRUE;
}
 
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/// <summary>
/// unsolicited tags initialization completed
/// <summary>
/// <returns>TRUE/FALSE</returns>
int    RandomValueSimulator::ihCollectorToolkitASyncInitCompleted(void)
{
       return TRUE;
}
 
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/// <summary>
/// Custom Collector Initialization completed and is ready to read data from Source for unsolicited tag 
/// <summary>
/// <returns>TRUE/FALSE</returns>
int    RandomValueSimulator::ihCollectorToolkitASyncStartReading(void)
{
       InterlockedExchange(&g_DoAsyncRead, TRUE);
       return TRUE;
}
 
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/// <summary>
/// Adds unsolicited tag to the historian
/// <summary>
/// <param name="ASyncTag">ihInterfaceTKAsyncTagInfo pointer</param>
/// <param name="IsCollectorStarting">Current Status of the Collector</param>
/// <returns>TRUE/FALSE</returns>
int    RandomValueSimulator::ihCollectorToolkitASyncAddTag(ihInterfaceTKASyncTagInfo *ASyncTag, int IsCollectorStarting)
{
       CSingleLock lock(&g_Sync, TRUE);
       g_AsyncTags.AddTag(ASyncTag);
       return TRUE;
}
 
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/// <summary>
/// From Clients tools/non-web admin/custom tools, if user deletes a tag, historian updates custom collector saying that tag got deleted.
/// So that, custom collector stops collecting data from source for that tag
/// <summary>
/// <param name="tagId">Tag Identifier</param>
/// <returns>TRUE/FALSE</returns>
int    RandomValueSimulator::ihCollectorToolkitASyncDeleteTag(int tagId)
{
       CSingleLock lock(&g_Sync, TRUE);
       POSITION pos = g_AsyncTags.GetHeadPosition();
       while (pos)
       {
              ihInterfaceTKASyncTagInfo * tagInfo = g_AsyncTags.GetAt(pos);
              if (tagInfo->TagId == tagId)
              {
                     g_AsyncTags.RemoveAt(pos);
                     return TRUE;
              }        
              g_AsyncTags.GetNext(pos);
       }
       return TRUE;
}
 
--------------------------------------------------------------------------------
 
/// <summary>
/// This method called by historian, if it needs to perform any calculations on source data. This method is only usefull in "calculation collector" way of collection for unsolicited tags
/// <summary>
/// <param name="StartTime"> start time for reload</param>
/// <param name="EndTime"> end time for reload</param>
/// <returns>TRUE/FALSE</returns>
int RandomValueSimulator::ihCollectorToolkitASyncReload(ihTKTimeStruct *StartTime, ihTKTimeStruct *EndTime)
{
       return CCollectorDelegator::ihCollectorToolkitASyncReload(StartTime, EndTime);
}
 
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/// <summary>
/// Unsolicited dedicated thread corresponding method. Here all unsolicited tags get data from source(usually, way should be source notification to historian) and sends to historian
/// <summary>
/// <param name="param"> Collector instance </param>
UINT RandomValueSimulator::TKAsyncReadFunc(void* param)
{
       POSITION pos = NULL;
       RandomValueSimulator* pColl = (RandomValueSimulator*) param;
       while (TRUE)
       {
              if (g_DoAsyncRead)
              {
                     CSingleLock lock(&g_Sync, TRUE);
                     if (!g_AsyncTags.IsEmpty())
                     {
                           // gets each unsolicited tag into ihInterfaceTKAsyncTagInfo object
                           if (!pos) 
                                  pos = g_AsyncTags.GetHeadPosition();
                           ihInterfaceTKASyncTagInfo* tag = g_AsyncTags.GetNext(pos);
                           int numTags = 1;
                           ihInterfaceTKDataInfo data;
                           memset(&data, 0, sizeof(ihInterfaceTKDataInfo));
                           data.Tag = pColl->TKStrdup(tag->Tag);
                           data.DataProp.ValueDataType = tag->DataType;                         
                           data.DataProp.TimeStamp = pColl->TKGetSystemTime();
                           // gets data for selected tag
                           pColl->ihCollectorToolkitGetData(0, 0, 0, numTags, NULL, &data);
                           unsigned long collectionTime = (unsigned long)time(0);
                           int tagId = tag->TagId;
                            ihInterfaceTKASyncData asyncData;
                           memset(&asyncData, 0, sizeof(ihInterfaceTKASyncData));
                           asyncData.NumValues = numTags;
                           asyncData.TagIds = &tagId;
                           asyncData.Values = &data.DataProp;
                           asyncData.CollectionTimes = &collectionTime;
                           // sends to historian
                           pColl->ihCollectorToolkitDataCallback(&asyncData);
                     }
                     else
                     {
                           pos = NULL;
                     }
              }
              else
              {
                     pos = NULL;
              }
              long sleepTimeInMs = 500 + (rand() % 46) * 100; // sleep from 0.5 to 5 seconds
              Sleep(sleepTimeInMs);
       }
       return 0;
}