Plovdiv-Flow

Real-time traffic monitoring and analytics platform for Plovdiv, Bulgaria

3D-visualization

An Unique way to track and navigate within your city

Development

Run the backend API:

cd backend
npm run dev

Run the frontend:

cd frontend
npx vite --host 127.0.0.1 --port 5174

The frontend calls /api/routes, which is proxied to the backend on port 8787.

Routing

The frontend does not call paid routing providers directly. The backend owns route calculation through /api/routes.

For development, the backend uses public demo routing endpoints so routes follow the road network without an API key:

• car routes use OSRM
• bike and walk routes use Valhalla

OSRM_BASE_URL=http://localhost:5000
VALHALLA_BASE_URL=http://localhost:8002

This keeps the final app free of paid API dependencies and keeps provider logic out of the browser.

Traffic-aware car routing

Car routes use TomTom with live traffic and departure set to now when TOMTOM_API_KEY is set in the ignored backend/.env file. The server loads this file automatically. No paid plan is enabled by the application.

TOMTOM_DAILY_LIMIT defaults to 100 and cannot exceed 100. Attempts are counted before sending, persisted in backend/.traffic-usage.json, and reset by UTC date. Keep this file across restarts. This local counter is for one server instance; it does not account for other apps using the same TomTom account. Keep the provider account on its free plan without paid overage. Do not delete the counter to reset usage.

Missing credentials, exhausted budget, or provider errors fall back to OSRM without live traffic. The sidebar identifies missing traffic data. Traffic is fetched when calculating a car route, not continuously refreshed. Bike and walking routes still use Valhalla. The optional traffic overlay is proxied through the backend, cached for five minutes, and capped by TOMTOM_TILE_MONTHLY_LIMIT (maximum 5000). Route traffic and colored traffic tiles use separate counters.