KafkaEvent.java

package com.cyngn.kafka.consume;

import com.cyngn.kafka.config.ConfigConstants;
import io.vertx.core.json.JsonObject;
import org.apache.kafka.clients.consumer.ConsumerRecord;

/**
 * Represents a Kafka message event from the event bus.
 *
 * @author truelove@cyngn.com (Jeremy Truelove) 11/30/15
 */
public class KafkaEvent {
    public final String topic;
    public final String key;
    public final String value;
    public final int partition;

    public KafkaEvent(JsonObject event) {
        topic = event.getString(ConfigConstants.TOPIC_FIELD);
        key = event.getString(ConfigConstants.KEY_FIELD);
        value = event.getString(ConfigConstants.VALUE_FIELD);
        partition = event.getInteger(ConfigConstants.PARTITION_FIELD);
    }

    @Override
    public String toString() {
        return "KafkaEvent{" +
                "topic='" + topic + '\'' +
                ", key='" + key + '\'' +
                ", value='" + value + '\'' +
                ", partition=" + partition +
                '}';
    }

    /**
     * Convert a Kafka ConsumerRecord into an event bus event.
     *
     * @param record the Kafka record
     * @return the record to send over the event bus
     */
    public static JsonObject createEventForBus(ConsumerRecord<String,String> record) {
        return new JsonObject()
                .put(ConfigConstants.TOPIC_FIELD, record.topic())
                .put(ConfigConstants.KEY_FIELD, record.key())
                .put(ConfigConstants.VALUE_FIELD, record.value())
                .put(ConfigConstants.PARTITION_FIELD, record.partition());
    }
}