WIP

[demos/kafka/wordcount] / src / main / java / de / juplo / kafka / wordcount / top10 / Top10StreamProcessor.java

diff --git a/src/main/java/de/juplo/kafka/wordcount/top10/Top10StreamProcessor.java b/src/main/java/de/juplo/kafka/wordcount/top10/Top10StreamProcessor.java
index 276ca8e..811cf98 100644 (file)
--- a/src/main/java/de/juplo/kafka/wordcount/top10/Top10StreamProcessor.java
+++ b/src/main/java/de/juplo/kafka/wordcount/top10/Top10StreamProcessor.java
@@ -6,19 +6,22 @@ import de.juplo.kafka.wordcount.avro.Key;
 import de.juplo.kafka.wordcount.avro.Ranking;
 import io.confluent.kafka.serializers.AbstractKafkaSchemaSerDeConfig;
 import io.confluent.kafka.streams.serdes.avro.SpecificAvroSerde;
+import io.confluent.kafka.streams.serdes.avro.SpecificAvroSerializer;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.kafka.clients.consumer.ConsumerConfig;
 import org.apache.kafka.common.serialization.Serdes;
-import org.apache.kafka.streams.KafkaStreams;
-import org.apache.kafka.streams.KeyValue;
-import org.apache.kafka.streams.StreamsBuilder;
-import org.apache.kafka.streams.StreamsConfig;
+import org.apache.kafka.streams.*;
+import org.apache.kafka.streams.kstream.Consumed;
+import org.apache.kafka.streams.kstream.Grouped;
+import org.apache.kafka.streams.kstream.Materialized;
+import org.apache.kafka.streams.kstream.Produced;
 import org.springframework.boot.SpringApplication;
 import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.stereotype.Component;
 
 import javax.annotation.PostConstruct;
 import javax.annotation.PreDestroy;
+import java.util.LinkedList;
 import java.util.Properties;
 import java.util.concurrent.CompletableFuture;
 import java.util.regex.Pattern;
@@ -43,29 +46,32 @@ public class Top10StreamProcessor
                StreamsBuilder builder = new StreamsBuilder();
 
                builder
-                               .<Key, Long>stream(properties.getInputTopic())
+                               .<Key, Long>stream(properties.getInputTopic(), Consumed.with(null, Serdes.Long()))
                                .map((key, count) -> new KeyValue<>(
                                                key.getUsername(),
                                                Entry.newBuilder().setWord(key.getWord()).setCount(count).build()))
-                               .groupByKey()
+                               .groupByKey(Grouped.keySerde(Serdes.String()))
                                .aggregate(
-                                               () -> Ranking.newBuilder().build(),
+                                               () -> Ranking.newBuilder().setEntries(new LinkedList<Entry>()).build(),
                                                (username, entry, ranking) -> {
                                                        ranking.getEntries().add(entry);
                                                        return ranking;
                                                })
                                .toStream()
-                               .to(properties.getOutputTopic());
+                               .to(properties.getOutputTopic(), Produced.keySerde(Serdes.String()));
 
                Properties props = new Properties();
                props.put(StreamsConfig.APPLICATION_ID_CONFIG, properties.getApplicationId());
                props.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, properties.getBootstrapServer());
-               props.put(StreamsConfig.DEFAULT_KEY_SERDE_CLASS_CONFIG, Serdes.String().getClass());
+               props.put(StreamsConfig.DEFAULT_KEY_SERDE_CLASS_CONFIG, SpecificAvroSerde.class);
                props.put(StreamsConfig.DEFAULT_VALUE_SERDE_CLASS_CONFIG, SpecificAvroSerde.class);
                props.put(AbstractKafkaSchemaSerDeConfig.SCHEMA_REGISTRY_URL_CONFIG, properties.getSchemaRegistry());
                props.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest");
 
-               streams = new KafkaStreams(builder.build(), props);
+               Topology topology = builder.build();
+               log.info("Topology:\n-----------------\n\n{}-----------------", topology.describe());
+
+               streams = new KafkaStreams(topology, props);
                streams.setUncaughtExceptionHandler((Throwable e) ->
                {
                        log.error("Unexpected error!", e);