Project Name: Payment Gateway Backend

Project Overview:

This project is a payment gateway system built using NestJS, TypeScript, Express, gRPC, Redis, PostgreSQL, and GraphQL. It provides a modular and scalable architecture to handle user authentication, authorization, fraud detection, currency conversion, payment methods, and communication via Kafka.

Tech Stack:

NestJS: A progressive Node.js framework for building scalable and maintainable server-side applications.
TypeScript: A superset of JavaScript that adds static types to the language, enhancing code readability and maintainability.
Express: A fast, unopinionated, minimalist web framework for Node.js, used as the underlying web server in NestJS.
gRPC: A high-performance RPC (Remote Procedure Call) framework that enables efficient communication between microservices.
Redis: An in-memory data structure store used as a caching layer for quick data retrieval.
PostgreSQL: A powerful open-source relational database management system, chosen for persisting user and payment data.
GraphQL: A query language and runtime for APIs, providing a flexible and efficient alternative to traditional REST APIs.
Docker: A platform for developing, shipping, and running applications in containers, ensuring consistent deployment across different environments.
Kafka: A distributed event streaming platform used for asynchronous communication between different parts of the application.
RabbitMQ: A message broker that enables communication between microservices and supports different messaging patterns.
Passport: A middleware for handling user authentication strategies in Node.js applications.
Bcrypt: A library for hashing and salting passwords, enhancing security for user authentication.
JWT (JSON Web Tokens): A compact, URL-safe means of representing claims to be transferred between two parties, commonly used for authentication.

Project Structure:

/src: Main source code directory.
- /auth: User authentication and authorization module.
- /fraud: Fraud detection module.
- /currency: Currency conversion module.
- /payment-method: Payment method module.
- /user: User-related functionality (entity, service, controller).
- /payment: Payment processing functionality (entity, service, controller).
- /kafka: Kafka service for event-driven communication.
- /oauth: OAuth module for external authentication.
- /common: Shared configurations and utilities.
/graphql: GraphQL-related files and modules.
/grpc: gRPC-related files and modules.
/docker: Docker configuration files.

Usage:

Clone the repository:

git clone https://github.com/your-username/nestjs-payment-gateway.git

Install dependencies:
```
cd nestjs-payment-gateway
npm install
```
Set up environment variables:

Create a .env file with necessary configuration details (e.g., database connection, Kafka/RabbitMQ details, OAuth credentials).
Start the application:
```
npm run start
```

Contribution Guidelines:

Fork the repository.
Create a new branch for your feature or bug fix.
Make changes and submit a pull request.
Ensure proper documentation and code quality.

License:

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

Contributors:

Your Name (@SQLSorcerer)

blacktscoder/payment-gateway