Kafka Pub/Sub Project

Overview

This repository contains a sample implementation of a Kafka-based Publisher and Subscriber using Spring Boot. The project demonstrates how to publish and consume messages via Kafka, with WebSocket integration for real-time updates.

Architecture

• kafka-publisher: Publishes messages to Kafka topics via REST/WebSocket endpoints.
• kafka-subscriber: Subscribes to Kafka topics and forwards messages to clients via WebSocket.
• Kafka: Managed via Docker Compose for local development.

[Client] <--WebSocket--> [Publisher] <--Kafka--> [Subscriber] <--WebSocket--> [Client]

Prerequisites

• Java 17+
• Docker & Docker Compose
• Gradle

Setup & Running Locally

1. Clone the repository

   git clone <repo-url>
   cd kafka-pub-sub

2. Start Kafka using Docker Compose

   docker-compose up -d

3. Build and run Publisher

   cd kafka-publisher
   ./gradlew bootRun

4. Build and run Subscriber

   cd kafka-subscriber
   ./gradlew bootRun

Usage

• Publish a message: Send a POST request to the publisher's REST endpoint or use the WebSocket interface.
• Receive messages: Connect to the subscriber's WebSocket endpoint to receive real-time updates.

Configuration

• Edit src/main/resources/application.properties in each service to configure Kafka brokers, topics, and WebSocket settings.
• Example:

  # Kafka broker address
  spring.kafka.bootstrap-servers=localhost:9092
  # Topic name
  kafka.topic.name=messageQueue

Testing

• Run unit and integration tests using Gradle:

  ./gradlew test

Contribution Guidelines

• Use JavaDoc for all public classes and methods.
• Add comments to configuration files explaining each property.
• Follow standard naming conventions and keep code self-explanatory.
• Submit pull requests with a clear description of changes.

License

This project is licensed under the MIT License.

Troubleshooting

• Ensure Kafka is running before starting publisher/subscriber services.
• Check application logs for errors.
• For Docker issues, run docker-compose logs.

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For more details, see the documentation guidelines in the repository.