QR-based Entry-Exit System (Backend)

This repository contains the backend part of the QR-based Entry-Exit System, which securely handles user authentication, QR code data processing, and entry/exit logging for university campuses.

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Table of Contents

• Technologies Used
• Features
• Installation
• API Endpoints
• Code Snippets
• Future Enhancements
• License

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Technologies Used

• Node.js: JavaScript runtime for server-side development.
• Express.js: Web framework for building REST APIs.
• MongoDB: NoSQL database for storing user and log data.
• Mongoose: ODM (Object Data Modeling) library for MongoDB.
• bcrypt.js: Library for password hashing.

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Features

• User registration and authentication with password hashing.
• QR code-based entry and exit logging.
• Secure RESTful API for frontend communication.

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Installation

Prerequisites

• Node.js and npm installed.
• MongoDB installed or access to a cloud-based MongoDB instance.

Steps

1. Clone the repository:

   git clone 

2. Navigate to the project directory:

   cd qr-entry-exit-system-backend

3. Install dependencies:

   npm install

4. Create a .env file with the following variables:

   MONGO_URI=your_mongodb_connection_string
   PORT=5000
   JWT_SECRET=your_secret_key
   

5. Start the server:

   npm start

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API Endpoints

Authentication

Register User

POST /api/auth/register

• Request Body:

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

• Response:

  {
    "message": "User registered successfully"
  }

Login User

POST /api/auth/login

• Request Body:

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

• Response:

  {
    "token": "jwt_token_here"
  }

Entry/Exit Logging

Log Entry or Exit

POST /api/logs

• Headers:

  {
    "Authorization": "Bearer jwt_token_here"
  }

• Request Body:

  {
    "qrCode": "sample_qr_code_data"
  }

• Response:

  {
    "message": "Entry logged successfully",
    "log": {
      "userId": "user_id_here",
      "timestamp": "2025-01-12T10:00:00Z"
    }
  }

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Code Snippets

User Schema with Mongoose

const mongoose = require('mongoose');
const bcrypt = require('bcryptjs');

const userSchema = new mongoose.Schema({
  name: {
    type: String,
    required: true
  },
  email: {
    type: String,
    required: true,
    unique: true
  },
  password: {
    type: String,
    required: true
  }
});

userSchema.pre('save', async function (next) {
  if (!this.isModified('password')) return next();
  const salt = await bcrypt.genSalt(10);
  this.password = await bcrypt.hash(this.password, salt);
  next();
});

module.exports = mongoose.model('User', userSchema);

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Future Enhancements

• Role-Based Access Control: Implement admin roles for better management.
• Activity Reporting: Add detailed reports for entry/exit logs.
• WebSockets: Enable real-time updates for logs.

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License

This project is licensed under the MIT License. See the LICENSE file for more information.