Taptag

TapTag is a full-stack, real-time RFID-based attendance management system built with ESP32, Flutter, and Express.js. Designed for seamless wireless authentication, analytics, and centralized logs using WebSockets and MongoDB.

Actions

Open GitHub Repository source for this project.

Features

RFID-Based Authentication: Register and log attendance using RFID cards and tags.
ESP32 + RC522: Microcontroller reads UID and encrypts using AES-256 before broadcasting over Wi-Fi.
WebSocket Integration: Real-time encrypted UID transmission to frontend app.
Wi-Fi Hotspot Mode: Reader runs a self-hosted access point.
Flutter App: Displays attendance logs, user data, and analytics.
Backend in Express.js: Built using TypeScript, connected to MongoDB Atlas via Mongoose.
RESTful API & WebSocket: Secured with rate limiting and served over Vercel with HTTPS.

Project Structure

arduino/ - ESP32 firmware with RFID, AES encryption, and WebSocket transmission.
flutter/ - Cross-platform mobile and web app for admin view.
express/ - RESTful API with JWT auth, user, tag, and attendance routes.

Hardware Requirements

ESP32 Dev Board
RFID-RC522 Module
RFID Cards/Tags
5V Power Supply
Jumper Wires, Optional PCB

Software Requirements

Arduino IDE (with ESP32 board support)
Node.js & npm
Flutter SDK
MongoDB Atlas
Postman (API testing)

Wiring Diagram

RFID RC522 Pin	ESP32 Pin
SDA (SS)	D5
SCK	D18
MOSI	D23
MISO	D19
IRQ	Not used
GND	GND
RST	D22
3.3V	3.3V

Setup & Installation

ESP32 Firmware

Install required libraries: WiFi, WebSocketsServer, MFRC522, AESLib, ArduinoJson.
Upload .ino firmware using Arduino IDE.
Configure Wi-Fi SSID and password or run in AP mode.
Firmware encrypts UID and broadcasts it via WebSocket on port 81.

Express Backend


cd express
npm install
# Set up .env with MONGODB_URI and JWT_SECRET
npm run dev

Hosted live at: https://api.taptag.s-m-quadri.me

Flutter App


cd flutter
flutter pub get
flutter run

Currently available for Web and Windows. Android version in development.

Backend & API

Base URL: https://api.taptag.s-m-quadri.me
WebSocket Local URL: ws://192.168.4.1:81
Full Postman Docs: TapTag API Docs

API Endpoints

POST /auth/register - Register new user
POST /auth/login - JWT-based login
CRUD for /user, /reader, /tag, /attendance

Security & Rate Limiting

TLS via Let’s Encrypt
Rate limit: 15 req/min (general), 6 req/2min (auth)
AES-256 encryption for UID transfer

Contributors & Acknowledgements

Finance & Presentation

Pawan Ramesh (MT24F11F001)
Yashashree S. Sawargaonkar (MT24F11F004)
Shubham Madane (MT24F05F007)

Full Stack Development

Syed Minnatullah Quadri (MT24F05F001)

Guide

Dr. Sushama Agrawal, Associate Professor, E&TC Department, GCOE, Sambhajinagar

For questions, contact: dev.smq@gmail.com

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