RocketMQ-Serializer

RocketMQ-Serializer is a RocketMQ extend library for serializing and deserializing message body. Both APIs and implements(string, json, avro...) are included in this module.

APIs

The core serializer & deserializer API are interfaces RocketMQSerializer and RocketMQDeserializer.
In order to centralized manage avro schemas, you can implement SchemaRegistry interface in rocketmq-serializer-avro module, and use SchemaRegistry registering and getting schemas.

Implementations

Supported Formats

Format	Serializer	Deserializer
Raw String	Y	Y
JSON	Y	Y
Avro Generic	Y	Y
Avro Specified	Y	Y

Some serializer performance research please refer to https://github.com/vongosling/jvm-serializer.

User Defined Formats

You can define your format just implements RocketMQSerializer and RocketMQDeserializer.

Tools

Messages provides methods like newMessage and getMessageBody to map between user class and byte array.
AvroUtils provides methods newGenericRecord and newSchema to create avro records and schemas.

Examples

Producer Example

DefaultMQProducer producer = new DefaultMQProducer("producer-group-json");
        producer.setNamesrvAddr("localhost:9876");
        producer.start();

        // creating serializer for message body serializing
        RocketMQSerializer serializer = new RocketMQJsonSerializer<User>();

        for (int i = 0; i < 100; i++) {
            User user = new User();
            user.setName("tom");
            user.setAge(i);

            // creating message from user data.
            Message message = Messages.newMessage("topic-json", user, serializer);
            SendResult result = producer.send(message);
            System.out.print(result.getSendStatus() + " " + i + "\n");

            Thread.sleep(1000);
        }

Consumer Example

DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("consumer-group-json");
        consumer.setNamesrvAddr("localhost:9876");
        consumer.subscribe("topic-json", "*");

        // creating deserializer for message body deserializing
        RocketMQDeserializer deserializer = new RocketMQJsonDeserializer<>(User.class);

        consumer.registerMessageListener(new MessageListenerConcurrently() {
            @Override
            public ConsumeConcurrentlyStatus consumeMessage(List<MessageExt> list,
                                                            ConsumeConcurrentlyContext consumeConcurrentlyContext) {
                for (MessageExt messageExt : list) {
                    // getting data from message.
                    User user = Messages.getMessageBody(messageExt, deserializer);
                    System.out.print(user.getName() + ":" + user.getAge() + "\n");
                }
                return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
            }
        });

        consumer.start();

Internals

rocketmq-serializer-avro is powered by Apache Avro, and rocketmq-serializer-json is powered by fastjson.