TouristGuardian — Smart Tourist Safety & Incident Response (SIH)

A full-stack system for tourist safety monitoring, SOS handling, and on-chain identity, built for Smart India Hackathon (SIH).

Stack: React + Node/Express + MongoDB + Solidity (Truffle/Ganache) + Leaflet with an IoT simulation for live movement.

Overview

• Blockchain identity: Every tourist gets a tamper-proof on-chain ID
• Live map: Real-time location tracking via IoT simulation
• SOS flow: Trigger, visualize, and resolve emergencies
• Admin console: Monitor tourists, filter/search, manage alerts
• Analytics: Basic KPIs, density heatmaps, SOS timelines

Architecture

• Frontend: React (CRA) + Tailwind + Leaflet
• Backend: Node/Express + MongoDB
• Blockchain: Solidity + Truffle + Ganache (local dev)
• Data: MongoDB Atlas (or local MongoDB)
• Real-time: IoT simulator (server-side, 5s updates)

├── backend/           # Express API & services
├── frontend/          # React UI (Admin dashboard + map)
├── blockchain/        # Truffle project (contracts, migrations)
├── contracts/         # Solidity source
└── migrations/        # Truffle deployment scripts

Prerequisites

• Node.js ≥ 16
• npm ≥ 8
• MongoDB Atlas (or local MongoDB)
• Ganache (v7+): npm i -g ganache
• Truffle: npm i -g truffle

Never commit real secrets. Use .env files locally and commit only .env.example.

Quick Start (Local Dev)

1) Clone & install

git clone <your-repo-url>
cd tourist-safety-system

npm install
cd backend && npm install && cd ..
cd frontend && npm install && cd ..
cd blockchain && npm install && cd ..

2) Start Ganache (deterministic, local-only)

Use the same mnemonic across restarts so addresses/private keys stay stable.

ganache \
  --wallet.mnemonic "bonus predict custom timber never advice casual glove predict hand burger away" \
  --wallet.totalAccounts 10 \
  --chain.chainId 1337 \
  --port 8545 \
  --host 127.0.0.1

Do not use this mnemonic in production.

3) Deploy the smart contract (Truffle)

cd blockchain
truffle migrate --reset --network development

Note the deployed contract address printed here.

4) Configure environment (backend)

Create backend/.env from the example and edit values:

cd backend
cp .env.example .env

Set:

• MONGODB_URI
• ADMIN_PRIVATE_KEY (Ganache account[0] PK printed by Ganache)
• CONTRACT_ADDRESS (from truffle migrate)
• BLOCKCHAIN_RPC_URL (http://127.0.0.1:8545)

5) Start the services

Backend

cd backend
npm start

Frontend

cd frontend
npm run dev

Open http://localhost:3000

Configuration

Backend .env (see .env.example)

• PORT (default 5000)
• MONGODB_URI
• BLOCKCHAIN_RPC_URL (e.g., http://127.0.0.1:8545)
• ADMIN_PRIVATE_KEY (Ganache account[0] private key)
• CONTRACT_ADDRESS (from Truffle deploy)

Contract sync

Each time you run truffle migrate --reset, update:

• CONTRACT_ADDRESS in .env
• If your backend uses a deployment.json, sync address + ABI there as well

Admin

Demo creds (dev only) — change in production:

• Username: admin
• Password: admin123

API Endpoints (sample)

Method	Endpoint	Description
POST	/api/tourists/register	Register new tourist
GET	/api/tourists	List all tourists (admin)
POST	/api/tourists/:id/location	Update tourist location
POST	/api/tourists/:id/sos	Trigger SOS
POST	/api/tourists/:id/reset-sos	Reset SOS (admin)
GET	/api/wallet-queue/status	Wallet queue status

Smart Contract (key functions)

• registerTourist(...) → emits TouristRegistered(id, ...)
• updateLocation(uint id, int256 lat, int256 long)
• triggerSOS(uint id)
• resetSOS(uint id) (admin)
• getTourist(uint id) view (admin)
• getAllTourists() view (admin)
• deleteTourist(uint id) (admin, post-trip)

Map & Analytics

• Live Map: 5s location updates, SOS markers, popups
• Heatmap: density visualization
• Analytics: active tourists, SOS count, areas

Testing & IoT Simulation

• IoT simulation runs server-side and updates locations every 5 seconds.
• SOS events can be simulated randomly or via API.

Security Notes

• Do not commit real .env files or private keys.
• Ganache mnemonic/keys are dev-only.
• Validate inputs on both client & server.
• Use role checks on admin-only endpoints.

Troubleshooting

1. Admin wallet has 0 ETH

• Start Ganache with the stable mnemonic above
• Use Ganache account[0] private key in ADMIN_PRIVATE_KEY
• Ensure BLOCKCHAIN_RPC_URL points to 127.0.0.1:8545

2. BAD_DATA / could not decode result data (value="0x")

• The backend is talking to a wrong address or ABI
• Re-deploy, then update CONTRACT_ADDRESS and ABI where used

3. Mongo error: E11000 duplicate key ... tokenId/digitalID: null

• Legacy unique indexes exist from older schema
• The backend now drops tokenId_1/digitalID_1 on boot and enforces unique indexes on blockchainId and walletAddress

4. “Tourist X not registered on blockchain, skipping update”

• Mongo entry exists, but not on-chain
• Register on-chain or let the backend re-register and persist the id

Roadmap

• AuthN/AuthZ with JWT & RBAC
• WebSocket live updates (replace polling)
• On-chain event indexing for analytics
• Geo-fencing & automated alerts
• Offline-first mobile client

Contributing

PRs welcome. Please open an issue first for major changes.

Built for Smart India Hackathon (SIH) 🏆