TLMOF: Traffic Light Management Operating Framework

TLMOF is a high-performance, full-stack simulation of an intelligent urban traffic controller. It bridges the gap between Operating System kernel principles—like process scheduling and deadlock prevention—and real-world traffic flow optimization.

Built as part of an Operating Systems Digital Assignment, this project implements a custom Hybrid WMP-F Algorithm to manage road intersections with the same precision a kernel manages CPU tasks.

---

The "OS" Core & Novelty

Unlike standard "timer-based" traffic lights, TLMOS treats each lane as a Process and each intersection as a Resource.

1. Hybrid WMP-F Algorithm

The system utilizes a Weighted Max-Pressure Fair algorithm. It calculates "pressure" (queue length) and applies Weighted Fair Queuing (WFQ) to ensure that high-density roads are cleared without "starving" smaller side streets.

2. Deadlock Prevention

Utilizing a Distributed Wait-for Graph (WFG), the system detects potential "gridlocks" (circular wait conditions) and preemptively adjusts signal phases to break the cycle.

3. Emergency Preemption

A high-priority interrupt system that detects emergency vehicle signatures, triggering an immediate context switch to a "Green Wave" state while safely pausing low-priority traffic.

---

Tech Stack

Frontend

• React (TypeScript) + Vite: For a high-performance, reactive dashboard.
• Tailwind CSS + Radix UI: For a clean, modular, and accessible interface.
• React Query: For efficient state synchronization.

Backend

• Node.js & Express: Handling the core logic and scheduling.
• WebSockets (ws): Real-time traffic state updates.
• Passport & Express-Session: Secure administrative access.

Database

• PostgreSQL: Robust storage for traffic logs and analytics.
• Drizzle ORM: Type-safe database interactions.

---

Project Structure

TLMOF/
├── client/          # React + Vite frontend
├── server/          # Express backend (TypeScript)
├── shared/          # Shared types (Traffic states, Schedules)
├── attached_assets/ # Visual assets & Icons
├── drizzle.config.ts
└── package.json

---

Setup & Local Development

Requirements

• Node.js 20+ (Required for Vite 7)
• pnpm (Recommended package manager)
• PostgreSQL

1) Clone & Install

git clone [https://github.com/Mogu-code/Operating-System-TLMOF.git](https://github.com/Mogu-code/Operating-System-TLMOF.git)
cd Operating-System-TLMOF
pnpm install

2) Environment Variables

Create a .env file in the root folder of the project. This file is used to store your sensitive credentials:

DATABASE_URL=postgresql://username:password@localhost:5432/dbname
SESSION_SECRET=your_secret_key

Do not commit your .env file to GitHub. It is already included in your .gitignore

3) Database Setup

TLMOF uses Drizzle ORM for type-safe database management. To sync your schema with your local PostgreSQL instance, run:

pnpm run db:push

4) Run the App

To start the development server for both the frontend and backend simultaneously:

pnpm dev

Once the server is running, open your browser and go to: http://localhost:5000

Scripts

Use these commands to manage the lifecycle of the project: Command,Description

pnpm dev,Starts the dev server with Hot Module Replacement (HMR).
pnpm build,Compiles the project into optimized production bundles.
pnpm start,Runs the production-ready build of the application.
pnpm check,Runs TypeScript diagnostics to ensure type safety.
pnpm db:push,Pushes changes in schema.ts directly to the database.