README.md

🎟️ Eventify

Event Booking System

A full-stack event booking platform built as a SESD college project.
Demonstrates OOP principles, design patterns, and clean software architecture through a real, working application.

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📖 What is Eventify?

Eventify is a mini event ticketing system — think BookMyShow, but built from scratch for a Software Engineering course.

A user lands on the app, browses upcoming events, selects seats from an interactive seat map, picks a ticket type (VIP / General / Early Bird), chooses a payment method, and gets their booking confirmed — all in two clean pages.

The real purpose: showcase that every layer of the system is engineered properly — backend patterns, OOP models, database design, and a professional frontend that makes it all visible.

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✨ Features

Feature	Details
🔐 Auth	JWT-based login with role-based access
🎪 Events	Browse, create, publish, and cancel events
💺 Seat Map	Interactive grid — Available (green), Locked (yellow), Booked (red)
🎫 Tickets	Multi-tier pricing — VIP, General, Early Bird
💳 Payments	Strategy Pattern — Credit Card, PayPal, Bank Transfer
🔔 Notifications	Observer Pattern — Email, SMS, Push
📋 My Bookings	View complete booking history with live statuses

🎓 Note on UI Scope: The backend and database are fully architected and secured for all three roles (Attendee, Organizer, Admin). However, the frontend demo strictly focuses on the Attendee flow. This was a deliberate choice to visually demonstrate the most complex transaction pipelines (seat state management, factory pattern tickets, and strategy pattern payments) for presentation purposes.

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🛠️ Tech Stack

Backend — Node.js + Express

Technology	Role
Node.js + Express	REST API server
TypeScript	Type-safe code
PostgreSQL	Relational database (18 tables)
JWT + bcrypt	Authentication & password hashing
Jest	Unit testing

Frontend — React + Tailwind

Technology	Role
React 19 + Vite	Fast, modern UI
Tailwind CSS	Dark-themed styling
Axios	API client with JWT interceptors
React Router	Two-page routing
Lucide React	Clean iconography

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🏗️ Architecture

┌─────────────────────────────────────────┐
│            Frontend (React)             │
│  EventExplorer  →  BookingDashboard     │
└────────────────┬────────────────────────┘
                 │ HTTP (Axios)
┌────────────────▼────────────────────────┐
│           Backend (Express)             │
│  Routes → Middleware → Controllers      │
│              ↓                          │
│           Services                      │
│              ↓                          │
│      Models + Design Patterns           │
└────────────────┬────────────────────────┘
                 │
┌────────────────▼────────────────────────┐
│          PostgreSQL Database            │
└─────────────────────────────────────────┘

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🧩 Design Patterns

1. Strategy Pattern — Payments

Swap payment methods without changing business logic.

interface PaymentStrategy {
  pay(amount: number, info: PaymentInfo): Promise<PaymentResult>;
}

class CreditCardStrategy implements PaymentStrategy { ... }
class PayPalStrategy       implements PaymentStrategy { ... }
class BankTransferStrategy implements PaymentStrategy { ... }

2. State Pattern — Seat Management

Seats transition through defined states.

interface SeatState {
  lock(seat: Seat): boolean;
  book(seat: Seat): boolean;
}

class AvailableState implements SeatState { ... }  // 🟢 Green
class LockedState    implements SeatState { ... }  // 🟡 Yellow
class BookedState    implements SeatState { ... }  // 🔴 Red

3. Observer Pattern — Notifications

Notify multiple channels on booking events.

class NotificationService {
  notify(event: NotificationEvent): void {
    this.observers.forEach(obs => obs.update(event));
  }
}
// Observers: EmailNotification, SMSNotification, PushNotification

4. Factory Pattern — Ticket Creation

class TicketFactory {
  static createTicket(type: TicketCategory): Ticket {
    if (type === 'VIP')        return new VIPTicket();
    if (type === 'EARLY_BIRD') return new EarlyBirdTicket();
    return new GeneralTicket();
  }
}

5. Singleton Pattern — Logger

class Logger {
  private static instance: Logger;
  static getInstance(): Logger {
    if (!Logger.instance) Logger.instance = new Logger();
    return Logger.instance;
  }
}

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🔷 OOP Principles

Inheritance — User Hierarchy

abstract class User {
  protected id: string;
  protected email: string;
  abstract getRole(): string;
}

class Attendee  extends User { getRole() { return 'attendee'; } }
class Organizer extends User { getRole() { return 'organizer'; } }
class Admin     extends User { getRole() { return 'admin'; } }

Encapsulation — Seat Model

class Seat {
  private status: SeatStatus;
  private state: SeatState;

  public lock(userId: string): boolean {
    return this.state.lock(this, userId); // Controlled access
  }
}

Abstraction & Polymorphism — Notification Channels

interface NotificationObserver {
  update(event: NotificationEvent): void;
}

class EmailNotification implements NotificationObserver { ... }
class SMSNotification   implements NotificationObserver { ... }

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🌍 Deployment

The application is fully configured for production deployment using modern cloud platforms:

• Frontend: Vercel (React + Vite)
• Backend: Render (Node.js + Express)
• Database: Supabase (PostgreSQL)

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🚀 Getting Started

Prerequisites

• Node.js 18+
• PostgreSQL 15+
• npm

Setup

# 1. Clone the repo
git clone https://github.com/YashSharma64/SESD-Eventify.git
cd SESD-Eventify

# 2. Setup Backend
cd backend
npm install
cp .env.example .env       # Fill in your DB credentials
npm run db:init             # Initialize database tables
npm run dev                 # Starts on http://localhost:3000

# 3. Setup Frontend (new terminal)
cd ../frontend
npm install
npm run dev                 # Starts on http://localhost:5173

The frontend auto-authenticates using a test user on first load — no manual login needed for demo purposes.

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📡 API Endpoints

Auth

Method	Endpoint	Access
POST	/api/auth/register	Public
POST	/api/auth/login	Public
GET	/api/auth/me	Authenticated

Events

Method	Endpoint	Access
GET	/api/events	Public
GET	/api/events/:id	Public
POST	/api/events	Organizer / Admin
PATCH	/api/events/:id/publish	Organizer / Admin
GET	/api/events/venues/:venueId/seats	Public

Bookings

Method	Endpoint	Access
POST	/api/bookings	Attendee
GET	/api/bookings/my-bookings	Authenticated
GET	/api/bookings/:id	Authenticated
PATCH	/api/bookings/:id/cancel	Authenticated
POST	/api/bookings/:bookingId/payment	Authenticated

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🗃️ Database Design

PostgreSQL schema with 18 tables including proper normalization, foreign keys, indexes, and constraints.

See → ErDiagram.md

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🧪 Testing

# Run backend unit tests
cd backend && npm test

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📁 Project Documents

Document	Description
idea.md	Project concept and scope
classDiagram.md	Full class diagram
sequenceDiagram.md	Booking flow sequence
useCaseDiagram.md	Use cases by role
ErDiagram.md	Database ER diagram

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👤 Author

Yash Sharma — @YashSharma64

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_{SESD Project — Software Engineering & System Design}