Real-Time Payment Processing System

Description

This project aims to develop a highly scalable and fault-tolerant real-time payment processing system capable of handling concurrent transactions. The system is built using a microservices architecture, event-driven design, and distributed computing principles to ensure reliability.

Key Features

• Microservices Architecture:

  • Decomposes the system into independent microservices, such as:
    • Payment Gateway Service
    • Transaction Processing Service
    • Settlement Service
  • Each microservice handles a specific business capability.

• Event-Driven Architecture:

  • Utilizes Apache Kafka for asynchronous communication between microservices.
  • Decouples components to enable better scalability and fault tolerance.

• Distributed Transaction Processing:

  • Ensures data consistency and integrity across PostgreSQL and NoSQL databases.
  • Supports high volumes of concurrent transactions.

Images

Technology Stack

• Programming Language: Java (Spring Boot)
• Message Broker: Apache Kafka
• Databases:
  • Relational: PostgreSQL
  • NoSQL: MongoDB (or other NoSQL databases as needed)
• Frameworks:
  • Spring Boot for microservices development
  • Spring Data for database access
• Containerization: Docker

Architecture Diagram

[Client]
   |
   v
[Payment Gateway Service] --> [Apache Kafka] --> [Transaction Processing Service] --> [Databases (PostgreSQL/NoSQL)]
                                                    |
                                                    v
                                         [Settlement Service]

Key Components

1. Payment Gateway Service: Handles incoming payment requests and performs basic validation before passing messages to Kafka.
2. Transaction Processing Service: Manages the core business logic for processing transactions, ensuring data consistency, and updating the database.
3. Settlement Service: Finalizes transactions by reconciling with external financial institutions and updating the system's records.
4. Apache Kafka: Enables asynchronous, reliable communication between services.

Prerequisites

1. Java 17 or later
2. Apache Kafka
3. PostgreSQL and MongoDB
4. Docker (optional, for containerized deployment)
5. Maven or Gradle (for build management)

Usage

API Endpoints

1. Payment Gateway:

   • POST /api/payments - Initiates a payment.

2. Transaction Processing:

   • GET /api/transactions/{id} - Retrieves transaction details.

3. Settlement:

   • GET /api/settlements/{id} - Retrieves settlement status.

Sample Request

POST /api/payments
{
  "amount": 100.0,
  "currency": "INR",
  "source": "card",
  "destination": "merchant_account"
}

License

This project is licensed under the MIT License - see the LICENSE file for details.

Contact

For any inquiries or feedback, please contact:

• Name: Shamon Hashmi
• Email: shamonhashmi148@gmail.com
• GitHub: shamonhashmi