Websocket client does not receive data from Akka streams Source.queue - scala

Question

I am using Akka stream Source.queue as Source for websocket clients.
Reading from kafka topic with 10k records using kaka consumer API and offering it to Source.queue with buffer 100k.
I am using BroardcastHub for fan-out. The websocket client does not get any data but see records from kafka enqueued on offer result.
Appreciate any help.
def kafkaSourceQueue() = {
val sourceQueue = Source.queue[String](100000, OverflowStrategy.dropHead)
val (theQueue, queueSource)= sourceQueue.toMat(BroadcastHub.sink(bufferSize = 256))(Keep.both).run
val consumer = KafkaEventSource.initKafkaConsumer()
try {
while (true) {
val records = consumer.poll(polltimeout.toMillis)
for (record <- records.records(topic)) {
//println(record.value())
theQueue.offer(record.value()).onComplete{
case Success(QueueOfferResult.Enqueued) =>
println("enqueued")
case _ => println("Failed to enqueue")
}
}
}
}
finally {
if (consumer != null) {
println("consumer unsubscribed")
consumer.unsubscribe()
}
}
queueSource
}
private def logicStreamFlow: Flow[String, String, NotUsed] = {
Flow.fromSinkAndSourceCoupled(Sink.ignore, kafkaSourceQueue)
}
def websocketFlow: Flow[Message, Message, NotUsed] = {
Flow[Message]
.map{
case TextMessage.Strict(msg) => msg
case _ => throw new Exception("exception msg")
}
.via(logicStreamFlow)
.map { msg: String => TextMessage.Strict(msg) }
}
lazy private val streamRoute =
path("stream") {
handleWebSocketMessages {
websocketFlow
.watchTermination() { (_, done) =>
done.onComplete {
case Success(_) =>
log.info("Stream route completed successfully")
case Failure(ex) =>
log.error(s"Stream route completed with failure : $ex")
}
}
}
}
def startServer(): Unit = {
bindingFuture = Http().bindAndHandle(wsRoutes, HOST, PORT)
log.info(s"Server online at http://localhost:9000/")
}
def stopServer(): Unit = {
bindingFuture
.flatMap(_.unbind())
.onComplete{
_ => system.terminate()
log.info("terminated")
}
}