POS Server (Go + Fiber)

A modern Point of Sale backend server built with Go and Fiber framework, featuring automatic service discovery, persistent data storage, and real-time updates.

Features

• Service Discovery: Automatic server discovery using Zeroconf/mDNS
• Persistent Storage: SQLite database with full ACID compliance
• Real-time Updates: WebSocket support for live transaction updates
• Transaction Analytics: Daily transaction summaries and reports
• Session Management: Secure session-based authentication
• RESTful API: Complete API for all POS operations

Project Structure

.
├── api/
│   ├── handlers/     # HTTP request handlers
│   ├── middleware/   # Custom middleware functions
│   ├── models/       # Data models and database schemas
│   ├── database/     # Database connection and migrations
│   └── discovery/    # Service discovery implementation
├── Database/        # SQLite database storage
├── config/          # Application configuration
├── utils/           # Utility functions and helpers
├── main.go         # Application entry point
└── README.md       # This file

Requirements

• Go 1.21 or higher
• SQLite3

Getting Started

1. Install dependencies:

go mod download

2. Create database directory:

mkdir -p Database

3. Run the server:

go run main.go

The server will start on port 8000 by default and will be discoverable on your local network as _pos-server._tcp.local.

Environment Variables

• PORT: Server port (default: 8000)
• DB_PATH: SQLite database path (default: Database/pos.db)
• APP_ENV: Application environment (development/production)

Key Endpoints

Authentication

The server uses PIN-based authentication for staff members. On first run, it creates a default admin account:

• Name: Manny
• PIN: 0000
• Role: Admin

To authenticate:

curl -X POST -H "Content-Type: application/json" \
  -d '{"pin":"0000"}' \
  http://localhost:8000/staff/auth

Transactions

POST /transactions           # Create transaction
GET /transactions           # List transactions by date
GET /transactions/summary   # Get daily transaction summary
PUT /transactions/:id/refund # Refund transaction

Real-time Updates

WS /ws/transactions        # WebSocket for live updates

Development

Running Tests

go test ./...

Building for Production

go build -o pos-server

API Documentation

For detailed API documentation, see documentation.md