Pay Flow - Subscription Management System API

🔥 High-Impact Description

The Pay Flow - Subscription Management System API is a scalable, production-ready backend solution designed to manage real users, subscriptions, and transactions securely. With robust authentication, automated workflows, and seamless integration capabilities, it ensures efficient and secure subscription management for businesses of all sizes.

📜 Table of Contents

• Project Description

• The Problem We Are Solving

• What Our Project Is

• How It Works

• Project Timeline

  • Initial Stage

  • Current Stage

  • Future Stage

• Progress and Experience

  • Process 💭

  • Learnings 📚

• Improvement ✨

• Tech Stack

• Features

• Quick Start

  • Prerequisites

  • Installation

• Contributing

  • Guidelines for Contributing

  • Reviewing and Merging Pull Requests

• Conclusion

📌 Project Description

This API powers subscription-based platforms, offering authentication, user management, and automated billing workflows. It enhances security with JWT authentication, prevents abuse with rate limiting, and automates reminders using Upstash Redis.

❗ The Problem We Are Solving

Managing subscriptions manually is inefficient and error-prone. Businesses need an automated, scalable, and secure solution to handle user sign-ups, payments, renewals, and cancellations while preventing fraud.

🔍 What Our Project Is

A Node.js & Express.js-based API with MongoDB for data persistence, ensuring real-time subscription tracking, email notifications, and robust access control for businesses handling recurring payments.

⚙️ How It Works

1. User Authentication: Secure sign-up, login, and JWT-based authorization.

2. Subscription Plans: Define and manage multiple pricing tiers.

3. Automated Workflows: Scheduled reminders, payment retries, and expiration alerts.

4. Security Features: Rate limiting, bot protection, and API access controls.

📅 Project Timeline

✅ Initial Stage

• Designed the database schema and authentication flow.

• Integrated JWT authentication and role-based access control.

🚧 Current Stage

• Implementing automated email reminders and workflow triggers using Upstash.

• Enhancing security with Arcjet for bot protection.

🔮 Future Stage

• Integrating Stripe for seamless payments.

• Expanding to support GraphQL for more flexible API queries.

• Adding unit and integration testing for higher reliability.

🏆 Progress and Experience

💭 Process

• Research & Planning: Analyzed common subscription models.

• Implementation: Built secure authentication, user CRUD, and subscription plans.

• Testing & Optimization: Added middleware for global error handling and logging.

📚 Learnings

Through this project, we learned:

• API security best practices (JWT, rate limiting, bot protection).

• Efficient database design using MongoDB & Mongoose.

• Deploying scalable Node.js applications on VPS hosting.

🚀 Improvement ✨

While we've made significant progress, there's always room for improvement:

• Enhanced Payment Support: Implementing Stripe for seamless transactions.

• GraphQL API: Providing flexible data querying options.

• Comprehensive Testing: Adding unit & integration tests for higher stability.

🛠 Tech Stack

• Node.js – Backend runtime.

• Express.js – API framework.

• MongoDB & Mongoose – NoSQL database & ORM.

• JWT – Authentication & authorization.

• Arcjet – Rate limiting & security.

• Upstash (Redis) – Automated workflows.

• Nodemailer – Email notifications.

✨ Features

🛡 Security & Authentication

✔ JWT Authentication – Secure login & authorization.
✔ Rate Limiting & Bot Protection – Arcjet integration to prevent abuse.

📊 Subscription Management

✔ User CRUD Operations – Create, update, and manage users.
✔ Subscription Plans – Different pricing tiers for flexibility.
✔ Automated Workflows – Upstash-powered email reminders.

🏗 API Architecture

✔ Modular & Scalable – Well-structured routes & controllers.
✔ Global Error Handling – Middleware-based error management.
✔ Logging Mechanisms – Debugging & monitoring for stability.

⚡ Quick Start

Follow these steps to set up the project locally on your machine.

🔗 Prerequisites

Make sure you have the following installed:

• Git

• Node.js

• npm (Node Package Manager)

🛠 Installation

1. Clone the Repository

   https://github.com/GunaPalanivel/PayFlow.git
   cd PayFlow

2. Install Dependencies

   npm install

3. Set Up Environment Variables
   Create a .env file in the project root and add:

   PORT=5500
   SERVER_URL="http://localhost:5500"
   NODE_ENV=development
   DB_URI=your_mongodb_connection_string
   JWT_SECRET=your_secret_key
   JWT_EXPIRES_IN="1d"
   ARCJET_KEY=your_arcjet_key
   ARCJET_ENV="development"
   QSTASH_URL=http://127.0.0.1:8080
   QSTASH_TOKEN=your_upstash_token
   EMAIL_PASSWORD=your_email_password

4. Run the Project

   npm run dev

   Open http://localhost:5500 in your browser or test via Postman.

🌟 Contributing

🔄 Guidelines for Contributing

• Fork the repository and create a new branch for your feature.

• Follow coding best practices and write clean, maintainable code.

• Ensure all new code is tested before submitting.

✅ Reviewing and Merging Pull Requests

• All PRs require at least one code review.

• Include detailed commit messages for better tracking.

🎯 Conclusion

The Subscription Management System API simplifies subscription handling with a scalable, secure, and automated approach. With ongoing improvements like Stripe payments and GraphQL, this API is set to become a robust solution for businesses managing recurring revenue.