Kafka is a powerful, open-source stream processing platform that has become increasingly popular in recent years for its ability to handle large amounts of data and real-time streaming scenarios. Node.js, on the other hand, is a JavaScript runtime built on Chrome's V8 JavaScript engine, known for its ability to create scalable, high-performance network applications. In this blog post, we'll explore the ways in which Kafka and Node.js can be used together to build efficient, real-time data processing systems that can handle high volumes of data and traffic.

👋 You can also check my weekly posts in Linkedin

Requirements:

• Basic knowledge of nodejs
• Basic Knowledge of docker
• Basic knowledge of javascript

What we will do:

1. Set up kafka.
2. Set up two Node.js apps: one for the producer and one for the consumer.
3. sent message from producer and consume it
4. scenario: A user will be automatically created in the consumer when a producer is created.

Discuss some crucial terms:

• producer: a producer is a program that writes data to a Kafka cluster. The producer sends messages to one or more topics.
• consumer: a consumer is a program that reads data from a Kafka cluster.
• borker: A broker is a Kafka server that stores and serves data.
• topic: topics are the channels through which producers and consumers communicate
• partition: a partition is a unit of data storage in a topic. Each topic is divided into one or more partitions

Let's play the game:

To begin, we will install Kafka

• Install Docker: Kafka is typically run in a Docker container, so you will need to install Docker on your system if it is not already installed. Follow the instructions for your operating system to install Docker.

• we will need two Docker images:

  • wurstmeister/zookeeper
  • wurstmeister/kafka

1️⃣ Create a docker-compose.yml file and include the following in it.

version: "3"
services:
zookeeper:
image: 'wurstmeister/zookeeper:latest'
ports:
- '2181:2181'
environment:
- ALLOW_ANONYMOUS_LOGIN=yes
kafka:
image: 'wurstmeister/kafka:latest'
ports:
- '9092:9092'
environment:
- KAFKA_BROKER_ID=1
- KAFKA_LISTENERS=PLAINTEXT://:9092
- KAFKA_ADVERTISED_LISTENERS=PLAINTEXT://127.0.0.1:9092
- KAFKA_ZOOKEEPER_CONNECT=zookeeper:2181
- ALLOW_PLAINTEXT_LISTENER=yes
depends_on:
- zookeeper

2️⃣ Run the following command to start the containers (-d to start the containers in the foreground)

docker-compose up -d

3️⃣ Start kafka shell:(change kafka_kafka_1 by your container name)

docker exec -it <u>kafka_kafka_1</u> /bin/sh

4️⃣ Create Topic:

kafka-topics.sh --create --zookeeper zookeeper:2181 --replication-factor 1 --partitions 1 --topic your-topic-name-here

Additional CLIs:
▪️ kafka-topics.sh --list --zookeeper zookeeper:2181: list all topics.
▪️ docker ps: to show running containers.

and that's all.

Next step: Set up two Node.js apps

1️⃣ create a package.json:

npm init

2️⃣ install packages:

npm i express nodemon dotenv mongoose kafkajs

3️⃣ Now we will configure our producer:

4️⃣ Add the following two lines: (to your index)

the result : 👇

5️⃣ configure our consumer by adding this following in it:

6️⃣ now we will start our scenario:

First of all, create your model, controller, and route. Inside the controller, you must add the following two lines:
import {run} from "../utils/producer.js";
run(response);

like this example below: 👇

7️⃣ update our producer:

8️⃣ update our consumer:

THE RESULT 👏

from producer:

from consumer:

🪄Github-repo

In conclusion, Apache Kafka is a powerful distributed streaming platform that enables real-time data processing and stream processing applications. It can be integrated with Node.js, a popular JavaScript runtime, through the use of Kafka client libraries, allowing developers to build event-driven and data-driven applications using the two technologies together. Kafka is known for its scalability, high performance, and ability to handle high volumes of data, making it a valuable tool for building robust and scalable applications. However, it can also be complex to set up and maintain, and requires a good understanding of its architecture and configuration options in order to use it effectively. Overall, Kafka and Node.js can be a powerful combination for building efficient and scalable applications, and are worth considering for any project that requires real-time data processing or stream processing capabilities.