public async Task ProcessEventsAsync(PartitionContext context, IEnumerable <EventData> events)
{
try
{
var now = DateTime.UtcNow;
foreach (var eventData in events)
{
// We don't care about messages that are older than bufferTimeInterval
if ((eventData.EnqueuedTimeUtc + bufferTimeInterval) >= now)
{
// Get message from the eventData body and convert JSON string into message object
string eventBodyAsString = Encoding.UTF8.GetString(eventData.GetBytes());
// There can be several messages in one
IList <IDictionary <string, object> > messagePayloads;
try
{
// Attempt to deserialze event body as single JSON message
messagePayloads = new List <IDictionary <string, object> >
{
JsonConvert.DeserializeObject <IDictionary <string, object> >(eventBodyAsString)
};
}
catch
{
// Not a single JSON message: attempt to deserialize as array of messages
// Azure Stream Analytics Preview generates invalid JSON for some multi-values queries
// Workaround: turn concatenated json objects (ivalid JSON) into array of json objects (valid JSON)
if (eventBodyAsString.IndexOf("}{") >= 0)
{
eventBodyAsString = eventBodyAsString.Replace("}{", "},{");
}
if (eventBodyAsString.IndexOf("}\r\n{") >= 0)
{
eventBodyAsString = eventBodyAsString.Replace("}\r\n{", "},{");
}
if (!eventBodyAsString.EndsWith("]"))
{
eventBodyAsString = eventBodyAsString + "]";
}
if (!eventBodyAsString.StartsWith("["))
{
eventBodyAsString = "[" + eventBodyAsString.Substring(eventBodyAsString.IndexOf("{"));
}
messagePayloads = JsonConvert.DeserializeObject <IList <IDictionary <string, object> > >(eventBodyAsString);
}
var rnd = new Random();
foreach (var messagePayload in messagePayloads)
{
// Read time value
if (messagePayload.ContainsKey("timecreated"))
{
messagePayload["time"] = messagePayload["timecreated"];
}
if (messagePayload.ContainsKey("timearrived"))
{
messagePayload["time"] = messagePayload["timearrived"];
}
// process an alert
if (messagePayload.ContainsKey("alerttype") && messagePayload.ContainsKey("timecreated"))
{
Debug.Print("Alert message received!");
// If the IoTHub service client has not yet been created, go create it.
if (IoTHub == null)
{
IoTHub = new IoTHubHelper(Microsoft.Azure.CloudConfigurationManager.GetSetting("Azure.IoT.IoTHub.ConnectionString"));
}
// Send alert to device
if (IoTHub != null)
{
var alertMessage = JsonConvert.SerializeObject(messagePayload).ToString();
IoTHub.SendMessage(messagePayload["guid"].ToString(), alertMessage);
}
DateTime time = DateTime.Parse(messagePayload["timecreated"].ToString());
// find the nearest point
lock (sortedDataBuffer)
{
int idx = SearchHelper.FindFirstIndexGreaterThanOrEqualTo(sortedDataBuffer, time);
bool found = false;
string alertType = messagePayload["alerttype"] as string;
if (idx >= sortedDataBuffer.Values.Count)
{
idx = sortedDataBuffer.Values.Count - 1;
}
while (idx >= 0)
{
List <IDictionary <string, object> > dictList = sortedDataBuffer.Values[idx];
foreach (IDictionary <string, object> dict in dictList)
{
if (
(dict.ContainsKey("guid") && messagePayload.ContainsKey("guid") && messagePayload["guid"].ToString() == dict["guid"].ToString())
&&
(dict.ContainsKey("measurename") && messagePayload.ContainsKey("measurename") && messagePayload["measurename"].ToString() == dict["measurename"].ToString())
&&
(!messagePayload.ContainsKey("displayname") || dict.ContainsKey("displayname") && messagePayload["measurename"].ToString() == dict["measurename"].ToString())
)
{
// fill anomaly message
if (!messagePayload.ContainsKey("value"))
{
messagePayload["value"] = dict["value"];
}
if (!messagePayload.ContainsKey("displayname") && dict.ContainsKey("displayname"))
{
messagePayload["displayname"] = dict["displayname"];
}
if (!messagePayload.ContainsKey("time"))
{
messagePayload["time"] = messagePayload["timecreated"];
}
found = true;
break;
}
}
if (found)
{
break;
}
idx--;
}
}
}
if (messagePayload.ContainsKey("guid"))
{
var guid = messagePayload["guid"].ToString();
double val = Convert.ToDouble(messagePayload["value"]);
if (!MinMaxValue.ContainsKey(guid))
{
MinMaxValue.Add(guid, new MinMax {
min = val, max = val
});
}
MinMax tmp = MinMaxValue[messagePayload["guid"].ToString()];
if (tmp.min > val)
{
tmp.min = val;
}
if (tmp.max < val)
{
tmp.max = val;
}
}
// We want to read the time value from the message itself.
// If none is found we will use the enqueued time
DateTime messageTimeStamp = new DateTime();
if (messagePayload.ContainsKey("time"))
{
messageTimeStamp = DateTime.Parse(messagePayload["time"].ToString());
//if (GenerateAnomalies && rnd.Next(100) >= 95)
//{
// messagePayload.Add("alerttype", "testType");
// messagePayload.Add("dsplalert", "testAlert");
// messagePayload.Add("message", "Anomaly detected by Azure ML model.");
// messagePayload.Add("timestart", messagePayload["time"]);
// // correct value
// if (rnd.Next(2) == 1)
// messagePayload["value"] = MinMaxValue[messagePayload["guid"].ToString()].max * (1.01 + 0.05 * rnd.Next(100) / 100);
// else
// messagePayload["value"] = MinMaxValue[messagePayload["guid"].ToString()].min * (0.99 - 0.05 * rnd.Next(100) / 100);
//}
}
else if (messagePayload.ContainsKey("timestart"))
{
messageTimeStamp = DateTime.Parse(messagePayload["timestart"].ToString());
}
else
{
messageTimeStamp = eventData.EnqueuedTimeUtc;
}
// Build up the list of devices seen so far (in lieu of a formal device repository)
// Also keep the last message received per device (not currently used in the sample)
if (messagePayload.ContainsKey("guid") && !messagePayload.ContainsKey("valueAvg"))
{
string guid = messagePayload["guid"].ToString();
if (guid != null)
{
WebSocketEventProcessor.g_devices.TryAdd(guid, messagePayload);
}
}
// Notify clients
MyWebSocketHandler.SendToClients(messagePayload);
// Buffer messages so we can resend them to clients that connect later
// or when a client requests data for a different device
// Lock to guard against concurrent reads from client resend
lock (sortedDataBuffer)
{
if (!sortedDataBuffer.ContainsKey(messageTimeStamp))
{
sortedDataBuffer.Add(messageTimeStamp, new List <IDictionary <string, object> >());
}
sortedDataBuffer[messageTimeStamp].Add(messagePayload);
}
}
}
else
{
Debug.Print("Received old message timestamped:" + eventData.EnqueuedTimeUtc.ToString());
}
}
//Call checkpoint every minute
if (this.checkpointStopWatch.Elapsed > TimeSpan.FromMinutes(1))
{
await context.CheckpointAsync();
lock (this)
{
this.checkpointStopWatch.Restart();
}
// trim data buffer to keep only last 10 minutes of data
lock (sortedDataBuffer)
{
DateTime oldDataPoint = now - bufferTimeInterval;
// find the closest point
int idx = SearchHelper.FindFirstIndexGreaterThanOrEqualTo(sortedDataBuffer, oldDataPoint);
// trim
while (idx > 0 && sortedDataBuffer.Count > 0 && sortedDataBuffer.Keys[0] <= oldDataPoint)
{
sortedDataBuffer.RemoveAt(0);
}
}
}
}
catch (Exception e)
{
Trace.TraceError("Error processing events in EH {0}, partition {1}: {0}",
context.EventHubPath, context.Lease.PartitionId, e.Message);
}
}
