Real-Time Ride Hailing Tracker

A real-time ride-hailing tracking application demonstrating advanced full-stack concepts including WebSocket bi-directional communication, geospatial data handling, and event-driven architecture.

Overview

This project simulates a ride-hailing experience where users can request rides and see drivers moving in real-time on a map. It efficiently handles high-frequency updates using Redis and WebSockets.

Key Features

• Real-Time Driver Tracking: Drivers' locations update live on the map without refreshing.
• Geospatial Matching: Finds the nearest available driver to the pickup location.
• Event-Driven Updates: Uses WebSockets to push state changes (Ride Accepted, Driver at Pickup, etc.) to the client instantly.
• Simulation Scripts: Includes a script to simulate driver movement and behavior for testing.

Tech Stack

Backend

• NestJS: Progressive Node.js framework for scalable server-side applications.
• Redis: In-memory data store used for geospatial indexing (GEOADD, GEORADITUS) and pub/sub.
• Socket.io: Enables real-time, bi-directional communication between web clients and servers.
• SQLite: Lightweight SQL database for persisting trip and transaction data (via TypeORM).

Frontend

• Next.js: React framework for production-grade web applications.
• Leaflet / React-Leaflet: Open-source JavaScript library for interactive maps.
• Tailwind CSS: Utility-first CSS framework for rapid UI development.

Architecture

1. Client (Next.js): Connects to the WebSocket Gateway and listens for driverMoved and tripUpdate events.
2. Dispatcher Service: Handles ride requests, queries Redis for nearby drivers, and manages trip state.
3. Redis: Stores ephemeral driver locations and supports fast geospatial queries.
4. Driver Simulation: A script mimicking multiple drivers moving across the map and responding to job assignments.

Getting Started

Prerequisites

• Node.js (v18+)
• Redis Server (Running locally or remotely)
• NPM or Yarn

Installation

1. Clone the repository

   git clone https://github.com/thoraf20/realtime-tracker.git
   cd realtime-tracker

2. Backend Setup

   cd backend
   npm install
   cp .env.example .env
   # Update REDIS_URL in .env if needed

3. Frontend Setup

   cd ../frontend
   npm install

Running the Application

1. Start the Backend

   cd backend
   npm run start:dev

   The server will start on http://localhost:3000.

2. Start the Frontend

   cd frontend
   npm run dev

   The application will be available at http://localhost:3001 (or usually 3000/3001 depending on port availability).

3. Simulate Drivers To see the real-time tracking in action, run the driver simulation script:

   cd backend
   npx ts-node scripts/simulate_drivers.ts

   You should see drivers appearing and moving on the map!

License

This project is licensed under the MIT License.