EzyKafka Configuration

1. Configuration List

EzyKafka provides a list of configurations in bellow table:

#	Property	Default Value	Description
1	kafka.consumers	null	List of kafka consumers
2	kafka.producers	null	List of kafka producers

For every producer, EzyKafka provides bellow properties:

#	Property	Default Value	Description
1	topic	producer name	Name of the kafka topic
2	bootstrap.servers	localhost:9092	Kafka bootstrap servers
3	client.id	producer name	Kafka client id

You can find out the all properties of kafka producer in the ProducerConfig class

For every consumer, EzyKafka provides bellow properties:

#	Property	Default Value	Description
1	topic	consumer name	Name of the kafka topic
2	bootstrap.servers	localhost:9092	Kafka bootstrap servers
3	client.id	consumer name	Kafka client id for consumer
4	group.id	random uuid	Kafka group id for consumers

You can find out the all properties of kafka consumer in the ConsumerConfig class

Let's careful with group.id

Let's take a look bellow image:

You can see, in a group, there is only one consumer can poll message at a time. Example, you have Consumer Group 2 with Consumer1 and Consumer2, now Topic T1 has 2 messages: Message1, Message2, so maybe Consumer1 or Consumer2 will poll the both messages or Consumer1 poll Message1 and Consumer2 poll Message2.

So, if you want to broadcast a message to the all consumer, you will need set value for group.id property is difference for each consumer, or you don't need provide any value, EzyKafka will random an UUID for you.

2. An Example

Let's we neen create a producer and a consumer named hello-world, you can put bellow configuration to your application.yaml file:

# for application.yaml
kafka:
  producers:
    hello-world:
      hello-world: test
      bootstrap.servers: localhost:9092
      client.id: KafkaProducerExample
  consumers:
    hello-world:
      topic: hello-world
      group.id: KafkaConsumerExample

Or for application.properties file:

# for application.properties
kafka.producers.hello-world.topic=hello-world
kafka.producers.hello-world.bootstrap.servers=localhost:9092
kafka.producers.hello-world.client.id=KafkaProducerExample
kafka.consumers.hello-world.topic=test
kafka.consumers.hello-world.group.id=KafkaConsumerExample

3. Configure for producer

You can configure for producer like this:

EzyKafkaProxy kafkaProxy = EzyKafkaProxy.builder()
    .scan("com.tvd12.ezymq.example.kafka")
    .build();
EzyKafkaProducer producer = kafkaProxy.getProducer("hello-world");

4. Configure for consumer

You can configure for consumer like this:

EzyKafkaProxy.builder()
    .addSingleton(someSingleton)
    .scan("com.tvd12.ezymq.example.kafka")
    .build();

Please take a look ezymq-kafka for entire example

Next step

You can see how to build a push message system