Task Application Assignment

A scalable REST API built with Node.js and Express featuring JWT authentication, role-based access control, and a React frontend.

---

Tech Stack

Backend

• Node.js + Express.js
• PostgreSQL + Sequelize ORM
• JWT + bcryptjs (Authentication)
• Zod (Validation)
• Swagger UI (API Docs)
• Helmet + HPP + Rate Limiting (Security)

Frontend

• React.js + Vite
• React Router DOM
• Axios + JWT Interceptor
• React Hot Toast

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Project Structure

PrimetradeAI-backend-assignment/
├── backend/
│   ├── src/
│   │   ├── config/
│   │   │   ├── db.js           → PostgreSQL connection
│   │   │   └── swagger.js      → Swagger config
│   │   ├── controllers/
│   │   │   ├── authController.js   → Register, login, getMe
│   │   │   └── taskController.js   → CRUD operations
│   │   ├── middleware/
│   │   │   ├── auth.js         → JWT verification
│   │   │   ├── roleCheck.js    → Role-based access
│   │   │   └── errorHandler.js → Global error handler
│   │   ├── models/
│   │   │   ├── User.js         → User schema
│   │   │   ├── Task.js         → Task schema
│   │   │   └── index.js        → Model associations
│   │   ├── routes/
│   │   │   └── v1/
│   │   │       ├── auth.js     → Auth routes
│   │   │       ├── tasks.js    → Task routes
│   │   │       └── index.js    → Route aggregator
│   │   ├── utils/
│   │   │   └── response.js     → Consistent API responses
│   │   ├── app.js              → Express app setup
│   │   └── server.js           → Server entry point
│   ├── .env.example
│   └── package.json
├── frontend/
│   ├── src/
│   │   ├── api/
│   │   │   ├── axios.js        → Axios instance + interceptors
│   │   │   ├── auth.js         → Auth API calls
│   │   │   └── tasks.js        → Task API calls
│   │   ├── components/
│   │   │   ├── Navbar.jsx
│   │   │   └── ProtectedRoute.jsx
│   │   ├── context/
│   │   │   └── AuthContext.jsx → Global auth state
│   │   ├── pages/
│   │   │   ├── Login.jsx
│   │   │   ├── Register.jsx
│   │   │   └── Dashboard.jsx
│   │   └── App.jsx
│   └── package.json
├── SCALABILITY.md
└── README.md

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Getting Started

Prerequisites

• Node.js >= 18
• PostgreSQL running locally
• npm >= 9

1. Clone the repository

git clone https://github.com/YOUR_USERNAME/PrimetradeAI-backend-assignment.git
cd PrimetradeAI-backend-assignment

2. Backend setup

cd backend
npm install
cp .env.example .env

Fill in your .env file:

PORT=5000
NODE_ENV=development

DB_HOST=localhost
DB_PORT=5432
DB_NAME=primetradeai_db
DB_USER=postgres
DB_PASSWORD=your_postgres_password

JWT_SECRET=your_jwt_secret
JWT_EXPIRES_IN=7d

Create the PostgreSQL database:

psql -U postgres -c "CREATE DATABASE primetradeai_db;"

Start the backend:

npm run dev

3. Frontend setup

cd frontend
npm install
npm run dev

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Running with Docker

docker-compose up --build

This starts both backend and PostgreSQL automatically.

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API Endpoints

Auth

Method	Endpoint	Access	Description
POST	/api/v1/auth/register	Public	Register new user
POST	/api/v1/auth/login	Public	Login and get JWT
GET	/api/v1/auth/me	Protected	Get current user

Tasks

Method	Endpoint	Access	Description
GET	/api/v1/tasks	User/Admin	Get all tasks
GET	/api/v1/tasks/:id	User/Admin	Get task by ID
POST	/api/v1/tasks	User/Admin	Create new task
PUT	/api/v1/tasks/:id	Owner/Admin	Update task
DELETE	/api/v1/tasks/:id	Owner/Admin	Delete task

Admin sees all tasks. Users only see their own tasks.

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API Documentation

Swagger UI available at:

http://localhost:5000/api-docs

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Security Features

• JWT token authentication
• Password hashing with bcryptjs (12 salt rounds)
• Role-based access control (user / admin)
• HTTP parameter pollution protection (hpp)
• Security headers (helmet)
• Rate limiting — 100 req/15min globally, 10 req/15min on auth routes
• CORS restricted to frontend origin
• Request body size limited to 10kb
• Input sanitization (HTML tag stripping)

---

Database Schema

Users Table

Column	Type	Description
id	UUID	Primary key
name	VARCHAR(100)	Full name
email	VARCHAR	Unique email
password	VARCHAR	Hashed password
role	ENUM	user / admin
createdAt	TIMESTAMP	Auto-generated
updatedAt	TIMESTAMP	Auto-generated

Tasks Table

Column	Type	Description
id	UUID	Primary key
title	VARCHAR(200)	Task title
description	TEXT	Optional description
status	ENUM	pending / in_progress / completed
userId	UUID	Foreign key → users.id
createdAt	TIMESTAMP	Auto-generated
updatedAt	TIMESTAMP	Auto-generated

---

Environment Variables

Variable	Description	Example
PORT	Server port	5000
NODE_ENV	Environment	development
DB_HOST	Database host	localhost
DB_PORT	Database port	5432
DB_NAME	Database name	primetradeai_db
DB_USER	Database user	postgres
DB_PASSWORD	Database password	yourpassword
JWT_SECRET	JWT signing secret	randomlongstring
JWT_EXPIRES_IN	Token expiry	7d

---

Health Check

GET http://localhost:5000/health

Response:

{
  "status": "OK",
  "timestamp": "2024-01-01T00:00:00.000Z",
  "version": "v1"
}