How to get events count from Microsoft Azure EventHub?

Question

I want to get events count from Microsoft Azure EventHub. I can use EventHubReceiver.Receive(maxcount) but it is slow on big number of big events.

There is NamespaceManager.GetEventHubPartition(..).EndSequenceNumber property that seems to be doing the trick but I am not sure if it is correct approach.

Answer 1

EventHub doesn't have a notion of Message count, as EventHub is a high-Throughput, low-latency durable stream of events on cloud - getting the CORRECT current count at a given point of time, could be wrong the very next milli-second!! and hence, it wasn't provided :)

Hmm, we should have named EventHubs something like a StreamHub - which would make this obvious!!

If what you are looking for is - how much is the Receiver lagging behind - then EventHubClient.GetPartitionRuntimeInformation().LastEnqueuedSequenceNumber is your Best bet.

As long as no messages are sent to the partition this value remains constant :)

On the Receiver side - when a message is received - receivedEventData.SequenceNumber will indicate the Current sequence number you are processing and the diff. between EventHubClient.GetPartitionRuntimeInformation().LastEnqueuedSequenceNumber and EventData.SequenceNumber can indicate how much the Receiver of a Partition is lagging behind - based on which, the receiver process can Scale up or down the no. of Workers (work distribution logic).

more on Event Hubs...