Streamer

Simply showing what the streaming actor does for the sake of the demo. It is a org.apache.spark.streaming.receivers.Receiver. This receiver tracks the number of blocks of data pushed to Spark so that the demo can shut down once we assert the expected data has been saved to Cassandra.

The additional behavior of a Counter simply supports the demo shutdown once the Stream has sent all the randomly generated data to the Spark DStream for processing. Once completed, the Streamer triggers an Akka DeathWatch by

self ! PoisonPill

trait CounterActor extends Actor  with Logging {
protected val scale = 30
private var count = 0

protected def increment(): Unit = {
   count += 1
   if (count == scale) self ! PoisonPill
 }
}