Backend Overview

The backend is an Express.js REST API located at apps/backend/. It is compiled by Babel and run by Node.js.

Package Details

Field	Value
Package	@my-app/backend
Entry	src/app.js
Build out	dist/app.js
Dev server	nodemon + @babel/node
Port	3500 (production) / 3000 (default)

---

Directory Structure

apps/backend/src/
├── app.js                     ← Express app entry point
├── config/
│   └── app.config.js          ← JWT, port, DB config
├── controllers/               ← HTTP handlers + business logic
│   ├── *.controller.js
│   ├── *.business.js
│   └── admin/
│       ├── device.controller.js / device.business.js
│       ├── user.controller.js / user.business.js
│       └── unit.controller.js / unit.business.js
├── middleware/
│   └── auth.middleware.js     ← JWT + session validation guards
├── models/                    ← Mongoose schemas + models
├── routes/                    ← Express routers
│   ├── *.router.js
│   ├── device/
│   │   └── deviceSensorData.router.js
│   └── admin/
│       ├── device.router.js
│       └── user.router.js
├── services/
│   └── aws/
│       └── email.service.js   ← SES email (verification, alerts)
├── helpers/
│   ├── response.helper.js
│   ├── date.helper.js
│   ├── query.helper.js
│   └── paginaton.helper.js
├── database/
│   ├── index.js               ← factory + singleton
│   └── mongodb/               ← MongoDBDatabase + DB operation classes
└── interfaces/
    └── database.interface.js  ← abstract DB contract

---

App Entry (app.js)

The main Express application:

1. CORS — whitelists localhost, 127.0.0.1, *.intecoglogistech.com, *.amplifyapp.com; credentials: true
2. Middleware stack — cookieParser → express.json → express.urlencoded → bodyParser
3. MongoDB — mongoose.connect(process.env.MONGODB_URI)
4. Routes — mounts all routers under /api/v1/

Mounted Routes

Mount Path	Router
/api/v1/user	routes/user.router.js
/api/v1/auth	routes/auth.router.js
/api/v1/unit	routes/unit.router.js
/api/v1/report	routes/report.router.js
/api/v1/recipient	routes/recipient.router.js
/api/v1/device	routes/device.router.js
/api/v1/devices/sensor-data	routes/device/deviceSensorData.router.js
/api/v1/admin/devices	routes/admin/device.router.js
/api/v1/admin/users	routes/admin/user.router.js

---

Key Dependencies

Package	Purpose
express	HTTP server framework
mongoose	MongoDB ODM
jsonwebtoken	JWT signing + verification
bcryptjs	Password hashing
@aws-sdk/client-ses	AWS SES v3 for email sending
aws-sdk	AWS SDK v2 (S3, Lambda)
helmet	Security headers
cors	CORS policy enforcement
cookie-parser	Parse userAccessToken cookie
pdfkit	PDF report generation (streaming)
puppeteer	Headless browser for PDF generation
winston	Structured logging
moment-timezone	Date formatting for reports
http-status-codes	Named HTTP status constants

---

Babel Path Aliases

The babel.config.js configures module-resolver aliases:

Alias	Resolves to
@	./src
@ctrl	./src/controllers
@helpers	./src/helpers
@db	./src/database
@tests	./src/__tests__

---

Config (src/config/app.config.js)

{
  port: process.env.PORT || 3000,
  jwt: {
    token_secret: process.env.JWT_SECRET || 'secret',
    token_life: 36000 * 24 * 30   // 30 days (in seconds)
  },
  viewsPath: 'views',
  publicPath: 'public'
}

WARNING

Always override JWT_SECRET with a strong secret in production via environment variable. The fallback 'secret' is unsafe.