Payment Processing System

This project implements a simple Payment Service Provider (PSP) system using Scala and Akka HTTP. It handles payment requests, validates them, and simulates interactions with a payment acquirer.

Features

• API Endpoint: Accepts payment details and processes them.
• Validation: Validations on fields for payment like credit card number is validated by luhn's algorithm.
• Mock Acquirer: Simulates transaction approval or denial based on card details.
• In-Memory Storage: Records transactions and their status changes.

Getting Started

Prerequisites

• Scala 2.13.13
• sbt (Scala Build Tool) 1.10.0

Installing

Clone the repository to your local machine:

git clone https://github.com/arunkmishra/PaymentSystem.git
cd paymentsystem

• Compile the project and run tests: sbt clean compile test
• Build docker image: docker build -t payment-system .

Running

Run locally

• To start the server, use: sbt run.

Run using docker

• Pull image
  • Mac: docker pull arunmishra/payment-system:latest
  • Linux/amd: docker pull arunmishra/paymentsystem_amd:latest
• Or build image docker build -t payment-system .
• Run application docker run -p 8080:8080 arunmishra/payment-system:latest
• Application will start on http://localhost:8080.

Usage

Check Status

To check application running status:

curl -X GET http://localhost:8080/status

Processing a Payment

To process a payment, send a POST request to /v1/api/payment with the following JSON payload:

{
"cardNumber": "4242424242424242",
"expiryDate": "12/27",
"cvv": 123,
"amount": 100.00,
"currency": "USD",
"merchantId": "merchant_001"
}

Curl to send the request:

curl -X POST http://localhost:8080/v1/api/payment \
-H "Content-Type: application/json" \
-d '{"cardNumber": "4242424242424242", "expiryDate": "12/27", "cvv": 123, "amount": 100.00, "currency": "USD", "merchantId": "merchant_001"}'

Viewing Logs

Check the logs for application at ./application.log file.

Data Encryption:

• In this implementation, sensitive data is not encrypted before storing to DB here. In this case, sensitive data includes credit card number, cvv.
• Ideally, aligning with PCI guidelines, we need to encrypt sensitive data before storing/logging it.
• For encryption, we can use AES or SHA-256, and store private key in some secure place where access is restricted to only some users(maybe vault).