Java Code Examples for org.apache.samza.operators.MessageStream#mergeAll()

The following examples show how to use org.apache.samza.operators.MessageStream#mergeAll() . You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.
Example 1
Source File: FlattenPCollectionsTranslator.java    From beam with Apache License 2.0 6 votes vote down vote up 
private static <T> MessageStream<OpMessage<T>> mergeInputStreams(
    List<MessageStream<OpMessage<T>>> inputStreams) {
  if (inputStreams.size() == 1) {
    return Iterables.getOnlyElement(inputStreams);
  }
  final Set<MessageStream<OpMessage<T>>> streamsToMerge = new HashSet<>();
  inputStreams.forEach(
      stream -> {
        if (!streamsToMerge.add(stream)) {
          // Merge same streams. Make a copy of the current stream.
          streamsToMerge.add(stream.map(m -> m));
        }
      });

  return MessageStream.mergeAll(streamsToMerge);
}
Example 2
Source File: WikipediaApplication.java    From samza-hello-samza with Apache License 2.0 4 votes vote down vote up 
@Override
public void describe(StreamApplicationDescriptor appDescriptor) {

  Duration windowDuration =
      appDescriptor.getConfig().containsKey("deploy.test") ? Duration.ofMillis(10) : Duration.ofSeconds(10);
  // Define a SystemDescriptor for Wikipedia data
  WikipediaSystemDescriptor wikipediaSystemDescriptor = new WikipediaSystemDescriptor("irc.wikimedia.org", 6667);

  // Define InputDescriptors for consuming wikipedia data
  WikipediaInputDescriptor wikipediaInputDescriptor = wikipediaSystemDescriptor
      .getInputDescriptor("en-wikipedia")
      .withChannel(WIKIPEDIA_CHANNEL);
  WikipediaInputDescriptor wiktionaryInputDescriptor = wikipediaSystemDescriptor
      .getInputDescriptor("en-wiktionary")
      .withChannel(WIKTIONARY_CHANNEL);
  WikipediaInputDescriptor wikiNewsInputDescriptor = wikipediaSystemDescriptor
      .getInputDescriptor("en-wikinews")
      .withChannel(WIKINEWS_CHANNEL);

  // Define a system descriptor for Kafka
  KafkaSystemDescriptor kafkaSystemDescriptor = new KafkaSystemDescriptor("kafka")
      .withConsumerZkConnect(KAFKA_CONSUMER_ZK_CONNECT)
      .withProducerBootstrapServers(KAFKA_PRODUCER_BOOTSTRAP_SERVERS)
      .withDefaultStreamConfigs(KAFKA_DEFAULT_STREAM_CONFIGS);

  // Define an output descriptor
  KafkaOutputDescriptor<WikipediaStatsOutput> statsOutputDescriptor =
      kafkaSystemDescriptor.getOutputDescriptor("wikipedia-stats", new JsonSerdeV2<>(WikipediaStatsOutput.class));


  // Set the default system descriptor to Kafka, so that it is used for all
  // internal resources, e.g., kafka topic for checkpointing, coordinator stream.
  appDescriptor.withDefaultSystem(kafkaSystemDescriptor);
  MessageStream<WikipediaFeedEvent> wikipediaEvents = appDescriptor.getInputStream(wikipediaInputDescriptor);
  MessageStream<WikipediaFeedEvent> wiktionaryEvents = appDescriptor.getInputStream(wiktionaryInputDescriptor);
  MessageStream<WikipediaFeedEvent> wikiNewsEvents = appDescriptor.getInputStream(wikiNewsInputDescriptor);
  OutputStream<WikipediaStatsOutput> wikipediaStats = appDescriptor.getOutputStream(statsOutputDescriptor);

  // Merge inputs
  MessageStream<WikipediaFeedEvent> allWikipediaEvents =
      MessageStream.mergeAll(ImmutableList.of(wikipediaEvents, wiktionaryEvents, wikiNewsEvents));


  // Parse, update stats, prepare output, and send
  allWikipediaEvents
      .map(WikipediaParser::parseEvent)
      .window(Windows.tumblingWindow(windowDuration,
          WikipediaStats::new, new WikipediaStatsAggregator(), WikipediaStats.serde()), "statsWindow")
      .map(this::formatOutput)
      .sendTo(wikipediaStats);
}