Getting Started
Install KafkaJS using yarn
:
yarn add kafkajs
Or npm
:
npm install kafkajs
Let's start by instantiating the KafkaJS client by pointing it towards at least one broker:
const { Kafka } = require('kafkajs')
const kafka = new Kafka({
clientId: 'my-app',
brokers: ['kafka1:9092', 'kafka2:9092']
})
Now to produce a message to a topic, we'll create a producer using our client:
const producer = kafka.producer()
await producer.connect()
await producer.send({
topic: 'test-topic',
messages: [
{ value: 'Hello KafkaJS user!' },
],
})
await producer.disconnect()
Finally, to verify that our message has indeed been produced to the topic, let's create a consumer to consume our message:
const consumer = kafka.consumer({ groupId: 'test-group' })
await consumer.connect()
await consumer.subscribe({ topic: 'test-topic' })
await consumer.run({
eachMessage: async ({ topic, partition, message }) => {
console.log({
value: message.value.toString(),
})
},
})
Congratulations, you just produced and consumed your first Kafka message!
Run into issues? Be sure to take a look at the FAQ.