pos-system/docs/en/architecture/system-design.md

System Design

Overview

GoodGo Microservices Platform is built using a microservices architecture pattern with the following principles:

• Service Independence: Each service has its own database and can be deployed independently
• API Gateway: Traefik handles routing, load balancing, and cross-cutting concerns
• Shared Libraries: Common functionality is extracted into shared packages
• Infrastructure as Code: All infrastructure configurations are versioned
• Observability: Full monitoring, logging, and tracing capabilities

Architecture Diagram

┌─────────────┐     ┌─────────────┐
│   Web App   │     │ Mobile App  │
│  (Next.js)  │     │ (React Native)
└──────┬──────┘     └──────┬──────┘
       │                   │
       └──────────┬────────┘
                  │
         ┌────────▼────────┐
         │   Traefik       │
         │  (API Gateway)   │
         └────────┬─────────┘
                  │
    ┌─────────────┼─────────────┐
    │             │             │
┌───▼────┐   ┌───▼────┐   ┌───▼────┐
│ Auth  │   │ Future │   │ Future │
│Service │   │Service │   │Service │
└───┬────┘   └───┬────┘   └───┬────┘
    │            │            │
    └────────────┼────────────┘
                 │
    ┌────────────┼────────────┐
    │            │            │
┌───▼────┐  ┌───▼────┐  ┌───▼────┐
│Postgres│  │ Redis  │  │Prometheus│
└────────┘  └────────┘  └─────────┘

Components

Frontend Layer

• Web App: Next.js application with App Router
• Mobile App: React Native application

API Gateway

• Traefik: Reverse proxy, load balancer, SSL termination

Services Layer

• Auth Service: Authentication and authorization
• Future Services: Payment, Order, Notification, etc.

Infrastructure Layer

• PostgreSQL: Primary database
• Redis: Caching and session storage
• Prometheus: Metrics collection
• Grafana: Metrics visualization
• Loki: Log aggregation

Communication Patterns

• Synchronous: HTTP/REST for request-response patterns
• Asynchronous: Message queues (future implementation)
• Service Discovery: Docker networking and Kubernetes DNS

Data Management

• Database per Service: Each service owns its data
• API Composition: Services expose APIs for data access
• Event Sourcing: Future consideration for audit trails

Security

• Authentication: JWT tokens with refresh token rotation
• Authorization: Role-based access control (RBAC)
• Network Security: TLS/SSL, rate limiting, CORS
• Secrets Management: Environment variables, Kubernetes secrets