📱 Contact Manager API

A RESTful API for managing personal contacts with user authentication. Built with Node.js, Express.js, and MongoDB.

✨ Features

• 🔐 User registration and authentication with JWT
• 📇 Full CRUD operations for contacts
• 🔒 Password hashing with bcrypt
• 👤 User-specific contacts (each user can only access their own contacts)
• ⚡ Async error handling

🛠️ Tech Stack

• Runtime: Node.js
• Framework: Express.js
• Database: MongoDB with Mongoose ODM
• Authentication: JSON Web Tokens (JWT)
• Password Hashing: bcrypt

📋 Prerequisites

• Node.js (v14 or higher)
• MongoDB (local or Atlas)
• npm or yarn

🚀 Getting Started

1. Clone the repository

git clone https://github.com/yourusername/contact-manager.git
cd contact-manager

2. Install dependencies

npm install

3. Set up environment variables

Create a .env file in the root directory:

PORT=5000
MONGO_URI=mongodb://localhost:27017/contact-manager
JWT_SECRET=your_super_secret_key_here

4. Run the application

Development mode (with auto-reload):

npm run dev

Production mode:

npm start

The server will start on http://localhost:5000

📚 API Endpoints

Authentication

Method	Endpoint	Description	Auth Required
POST	/api/users/register	Register a new user	❌
POST	/api/users/login	Login user	❌
GET	/api/users/current	Get current user info	✅

Contacts

Method	Endpoint	Description	Auth Required
GET	/api/contacts	Get all contacts	✅
POST	/api/contacts	Create a contact	✅
GET	/api/contacts/:id	Get a contact	✅
PUT	/api/contacts/:id	Update a contact	✅
DELETE	/api/contacts/:id	Delete a contact	✅

📖 API Usage

Register a User

POST /api/users/register
Content-Type: application/json

{
  "username": "johndoe",
  "email": "john@example.com",
  "password": "password123"
}

Response:

{
  "_id": "64a1b2c3d4e5f6g7h8i9j0k1",
  "email": "john@example.com"
}

Login

POST /api/users/login
Content-Type: application/json

{
  "email": "john@example.com",
  "password": "password123"
}

Response:

{
  "message": "Login Successfully",
  "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."
}

Create a Contact

POST /api/contacts
Authorization: <your_jwt_token>
Content-Type: application/json

{
  "name": "Jane Doe",
  "email": "jane@example.com",
  "phone": "123-456-7890"
}

Response:

{
  "message": "Contact Created",
  "contact": {
    "_id": "64a1b2c3d4e5f6g7h8i9j0k2",
    "userId": "64a1b2c3d4e5f6g7h8i9j0k1",
    "name": "Jane Doe",
    "email": "jane@example.com",
    "phone": "123-456-7890",
    "createdAt": "2026-01-30T10:00:00.000Z",
    "updatedAt": "2026-01-30T10:00:00.000Z"
  }
}

Get All Contacts

GET /api/contacts
Authorization: <your_jwt_token>

Get Single Contact

GET /api/contacts/:id
Authorization: <your_jwt_token>

Update Contact

PUT /api/contacts/:id
Authorization: <your_jwt_token>
Content-Type: application/json

{
  "name": "Jane Smith",
  "phone": "987-654-3210"
}

Delete Contact

DELETE /api/contacts/:id
Authorization: <your_jwt_token>

📁 Project Structure

contact-manager/
├── config/
│   └── db.js              # Database connection
├── controllers/
│   ├── contactController.js   # Contact CRUD logic
│   └── userController.js      # User auth logic
├── middleware/
│   ├── auth.js            # JWT authentication
│   └── errorHandler.js    # Global error handler
├── models/
│   ├── contactModel.js    # Contact schema
│   └── userModel.js       # User schema
├── routes/
│   ├── contactRoutes.js   # Contact endpoints
│   └── userRoutes.js      # User endpoints
├── .env                   # Environment variables
├── constants.js           # HTTP status codes
├── package.json
├── README.md
└── server.js              # Entry point

🔒 Authentication

This API uses JWT (JSON Web Tokens) for authentication. After logging in, include the token in the Authorization header for all protected routes:

Authorization: <your_jwt_token>

Tokens expire after 1 day.

⚠️ Error Responses

The API returns consistent error responses:

{
  "title": "Error Type",
  "message": "Error description",
  "stackTrace": "..." 
}

Status Code	Title	Description
400	Validation Failed	Invalid input data
401	Unauthorized	Invalid or missing token
403	Forbidden	Access denied
404	Not Found	Resource not found
500	Server Error	Internal server error

👤 Author

Deepraj Singh

📄 License

This project is licensed under the ISC License.