Alex Brekken abrekken

abrekken / kstream_agg.java

Last active July 25, 2019 02:45

	@Bean
	public KStream<?, ?> kstreamAggregation(StreamsBuilder streamsBuilder) {
	KStream<String, IotEvent> stream = streamsBuilder.stream(inputTopic, Consumed.with(Serdes.String(), iotEventSerde()));
	stream
	.peek((key, value) -> LOG.debug("incoming message: {} {}", key, value))
	//re-partition our data on a new key
	.groupBy((key, value) -> eventKey(value), Grouped.with(Serdes.String(), iotEventSerde()))
	// add our incoming newValue into the aggregate
	.aggregate(IotEventMetric::new,
	(key, newValue, aggregate) -> aggregate.add(newValue),

abrekken / ks_windowed_agg.java

Last active June 19, 2019 00:32

	@Bean
	public KStream<?, ?> windowedAggregation(StreamsBuilder streamsBuilder) {
	WindowedSerializer<String> windowedSerializer = new TimeWindowedSerializer<>(new StringSerializer());
	TimeWindowedDeserializer<String> windowedDeserializer = new TimeWindowedDeserializer<>(new StringDeserializer());
	Serde<Windowed<String>> windowedSerde = Serdes.serdeFrom(windowedSerializer, windowedDeserializer);

	KStream<String, IotEvent> stream = streamsBuilder.stream(inputTopic, Consumed.with(Serdes.String(), new JsonSerde<>(IotEvent.class)));
	stream
	.peek((key, value) -> LOG.debug("incoming message: {} {}", key, value))
	//re-partition our data on a new key

abrekken / kafka_streams_punctuate.java

Last active June 3, 2020 17:18

	@Bean
	public KStream<?, ?> kstreamProcessorApi(StreamsBuilder streamsBuilder) {
	StoreBuilder<KeyValueStore<String, IotEvent>> eventStoreBuilder =
	Stores.keyValueStoreBuilder(Stores.persistentKeyValueStore("eventstore"),
	Serdes.String(), iotEventSerde());
	// register store
	streamsBuilder.addStateStore(eventStoreBuilder);
	KStream<String, IotEvent> stream = streamsBuilder.stream(inputTopic, Consumed.with(Serdes.String(), iotEventSerde()));
	stream
	.process(() -> new Processor<String, IotEvent>() {

abrekken / kafka_streams_tombstone.java

Last active April 19, 2020 19:09

	@Bean
	public KStream<?, ?> kstreamTombstone(StreamsBuilder streamsBuilder) {
	KStream<String, IotEvent> inbound = streamsBuilder.stream(inputTopic, Consumed.with(Serdes.String(), iotEventSerde()));
	inbound
	.peek((key, value) -> LOG.debug("incoming message: {} {}", key, value))
	//check for a null value (tombstone) and set delete flag if necessary
	.mapValues((readOnlyKey, value) -> {
	if (value == null) {
	value = new IotEvent();
	value.setDelete(true);