org.apache.pulsar.functions.api.examples.MergeTopicFunction Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.pulsar.functions.api.examples;
import lombok.extern.slf4j.Slf4j;
import org.apache.pulsar.client.api.Message;
import org.apache.pulsar.client.api.Schema;
import org.apache.pulsar.client.api.TypedMessageBuilder;
import org.apache.pulsar.client.api.schema.GenericRecord;
import org.apache.pulsar.functions.api.Context;
import org.apache.pulsar.functions.api.Function;
/**
* Merge various schemas data to a topic.
*/
@Slf4j
public class MergeTopicFunction implements Function {
@Override
public byte[] process(GenericRecord genericRecord, Context context) throws Exception {
if (context.getCurrentRecord().getMessage().isPresent()) {
Message msg = context.getCurrentRecord().getMessage().get();
if (!msg.getReaderSchema().isPresent()) {
log.warn("The reader schema is null.");
return null;
}
log.info("process message with reader schema {}", msg.getReaderSchema().get());
TypedMessageBuilder messageBuilder =
context.newOutputMessage(context.getOutputTopic(),
Schema.AUTO_PRODUCE_BYTES(msg.getReaderSchema().get()));
messageBuilder
.value(msg.getData())
.property("__original_topic", msg.getTopicName())
.property("__publish_time", String.valueOf(msg.getPublishTime()))
.property("__sequence_id", String.valueOf(msg.getSequenceId()))
.property("__producer_name", msg.getProducerName());
if (msg.getKeyBytes() != null) {
messageBuilder.keyBytes(msg.getKeyBytes());
}
if (msg.getEventTime() > 0) {
messageBuilder.eventTime(msg.getEventTime());
}
if (!msg.getProperties().isEmpty()) {
messageBuilder.properties(msg.getProperties());
}
messageBuilder.send();
log.info("send message successfully");
} else {
log.warn("context current record message is not present.");
}
return null;
}
}