NTPOS - Microservices-based Point of Sale System

Project Overview

This repository contains the source code for a Point of Sale (POS) system developed using a Microservices Architecture. The system consists of multiple services that work together to manage sales, inventory, orders, payments, and user authentication.

LINK DOCUMENT: https://drive.google.com/file/d/1IvQ5EC8E5ygKcWMda0t6Nc-wERDg7O1k/view

Source Code Structure

The project consists of multiple components:

Frontend Applications

1. ntpos_admin_mobile - Mobile application (React Native) for store owners and employees to manage sales.
2. ntpos_web - Web-based management system (React.js) for store owners and employees.
3. user_app - Mobile application (React Native) for customers to place orders and reserve tables.

Backend Microservices (ntpos-microservices)

Module	Description
api-gateway	Manages API routing and load balancing.
auth-service	Handles authentication (login, registration, and user management).
chat-service	Manages real-time messaging between users and support agents.
config-server	Centralized configuration management for all services.
discovery-server	Eureka server for service discovery.
inventory-service	Manages stock, supplier information, and inventory tracking.
notification-service	Handles system-wide notifications.
order-service	Manages order placement, reservations, and order tracking.
payment-service	Processes transactions and payments.
product-service	Manages product listings, categories, and images.
user-service	Integrates with Keycloak for user management and authentication APIs.

System Architecture

The system is designed following Microservices Architecture, divided into ten main components:

1. User Interfaces (UI Layer)

• React Native mobile app for store owners.
• React.js web-based admin panel for store management.
• React Native mobile app for customers to place orders and reserve tables.

2. Communication Layer

• GraphQL & REST API for frontend-to-backend communication (GraphQL as the primary API, REST for specific cases).
• gRPC for efficient service-to-service communication using HTTP/2.

3. gRPC Communication

• Used exclusively for backend-to-backend data exchange due to its speed and efficiency.

4. Management Services

• Eureka Server for service discovery and registration.
• Config Server for centralized service configuration.
• API Gateway for request routing, load balancing, and security enforcement.

5. Security Layer

• Keycloak provides OAuth 2.0-based authentication and user role management.

6. Core Business Services

Service	Functionality
payment-service	Manages transactions for orders, refunds, and supplier payments.
product-service	Handles product catalog management.
order-service	Manages order processing, returns, and table reservations.
user-service	Handles user management and role-based access.
inventory-service	Tracks stock levels and supplier data.

7. Supporting Services

Service	Functionality
notification-service	Sends system notifications and alerts.
auth-service	Provides user authentication and authorization APIs.
chat-service	Enables real-time customer support messaging.
resource-service	Manages file storage for images and documents.

8. Database & Persistence Layer

• JDBI for database connection management.
• MySQL as the primary relational database.

9. Event-Driven Architecture

• Kafka & Zookeeper handle event-driven messaging and asynchronous task processing.

10. Monitoring & Logging

Technology	Purpose
Zipkin	Distributed tracing of service requests.
Prometheus	Service health monitoring and alerting.
Grafana	Visualization of monitoring data from Prometheus.

Technologies Used

• Frontend: React Native, React.js
• Backend: Spring Boot (Java), Microservices
• Databases: MySQL
• Security: Keycloak, OAuth 2.0
• Message Queue: Apache Kafka, Zookeeper
• Logging & Monitoring: Zipkin, Prometheus, Grafana
• Configuration Management: Eureka, Config Server
• API Communication: GraphQL, REST, gRPC

Setup & Deployment

Prerequisites

• Java 17
• Node.js 16+
• Docker & Docker Compose
• PostgreSQL / MySQL
• Keycloak authentication server

Installation Steps

1. Clone the Repository:

   git clone git@github.com:thanhnguyenle/19130206_19130163_LUANVAN2023.git
   cd Backend/ntpos-microservices

2. Build Docker image for each modules:

   cd [name module]
   mvn clean package
   docker build -t [name_module] .

3. Start Services with Docker Compose:

   docker-compose up -d

4. Start Frontend Applications:

   cd ntpos_web && npm start
   cd ntpos_admin_mobile && npx react-native run-android