ChemE Process Simulation Suite (CPSS)

CPSS is a production-ready, enterprise-style 8-in-1 Chemical Engineering SaaS simulation platform with:

• Backend: Node.js + Express + MySQL (mysql2/promise)
• Auth: JWT + bcrypt
• Frontend: React (Vite) + Tailwind + lucide-react
• Design: Scientific glassmorphism dark interface
• Modules: Plume, Heat Exchanger, Pipe Flow, CSTR, Flash, Ergun, Fenske, PID
• Resilience: Automatic local math fallback when backend is unreachable

Project Structure

cpss1-project/
├── backend/
│   ├── middleware/
│   │   └── auth.js
│   ├── package.json
│   └── server.js
├── frontend/
│   ├── src/
│   │   └── App.jsx
│   └── package.json
└── README.md

1) Prerequisites

• Node.js 18+
• MySQL 8+

2) Database Setup

Create the DB once in MySQL (name can be changed through env):

CREATE DATABASE cpss1;

backend/server.js auto-creates:

• users table
• simulations table with JSON columns

3) Backend Setup

cd backend
npm install

Create .env in backend/:

PORT=5000
DB_HOST=localhost
DB_USER=root
DB_PASSWORD=your_mysql_password
DB_NAME=cpss1
JWT_SECRET=replace_with_long_random_secret

Run backend:

npm run dev

4) Frontend Setup

cd frontend
npm install
npm run dev

Vite default URL is usually http://localhost:5173.

The frontend expects backend at:

• http://localhost:5000

If needed, update API_BASE in frontend/src/App.jsx.

5) API Overview

Auth

• POST /api/auth/register
• POST /api/auth/login

Protected Simulation Routes

• POST /api/plume
• POST /api/heatexchanger
• POST /api/pipeflow
• POST /api/cstr
• POST /api/flash
• POST /api/ergun
• POST /api/fenske
• POST /api/pid

User History

• GET /api/history (returns last 20 simulations for logged-in user)

6) Local Fallback Mode

Every frontend fetch call is wrapped with try/catch.

If backend calls fail:

• Calculations run locally in JavaScript using the same formulas.
• Results are still shown to the user.
• Badge appears: Local Fallback Mode: Backend Unreachable. Results not saved.

7) Production Notes

• Move secrets to secure secret manager or deployment env vars.
• Put backend behind HTTPS reverse proxy (Nginx/Cloud LB).
• Restrict CORS origins in backend/server.js.
• Add rate limiting and request validation for public deployments.
• Add CI/CD checks and integration tests before release.