API Integration with Kafka and Spring Boot

Overview

In this assignment, implement a public API that interacts with an internal addition service. The addition service performs the addition of two numbers and posts the results to a Kafka topic named addition-service.results. The task is to build a public-api service that provides two endpoints:

1. /api/add: This endpoint forwards requests to the internal addition service, which performs the addition and posts the result to Kafka. It responds synchronously with an asyncId that corresponds to the request.
2. /api/list-results: This endpoint fetches and returns a list of all calculation results from the Kafka topic addition-service.results.

Project Structure

• ./public-api/: Place all implementation files for the public-api service in this folder. This folder should contain the code for both the /api/add and /api/list-results endpoints.
• ./addition-service/: Contains the source code for the internal addition service.
• ./docker-compose.yml: Describes the system architecture including the Kafka and Zookeeper services.
• ./public-api.yml: API specification for the public-api service.
• ./start.sh: Script to rebuild and start the system.

Implementation Details

1. API Implementation (public-api):

   • Implement the /api/add endpoint to forward requests to the internal addition service and return an asyncId.
   • Implement the /api/list-results endpoint to consume messages from the Kafka topic addition-service.results and respond with a list of all results.

2. Kafka Integration:

   • Use Kafka to fetch results from the addition-service.results topic.
   • Implement a Kafka consumer in public-api service to listen to this topic.

3. Security and Code Quality:

   • Ensure the API is secure and handles errors gracefully.
   • Write clean and maintainable code, and adhere to best practices for performance and scalability.

How to Run

1. Build and Start the System: Run the start.sh script to rebuild and start the entire system. This will build the Docker images and start the containers as described in docker-compose.yml.

   ./start.sh