JavaScript and JSON Essentials - Second Edition

Implementing the Kafka consumer

Moving on, let's implement the consumer concepts to our real-time app. This will complete our JSON message-passing implementation using Kafka. We are going to work on app.js for now, as it is a consumer for us:

1. Firstly, we need to create a consumer that will connect to a Kafka client on port 9092, which is the default port:

      const kafka = require('kafka-node'),          client = new kafka.Client(),          consumer = new kafka.Consumer(client,              [{ topic: 'pinBoard', offset: 0 }],              {                  autoCommit: false              }          );

Here, we have created a consumer instance that connects to Kafka with topics that are passed as array parameters to the kafka.Consumer method.

2. Create an error handler that will manage all the errors at the consumer side. ...