🗳️ Polling App — Full-Stack Polling & Voting Platform

🚀 Live Demo: https://pollingapp-c178.onrender.com/

A modern full-stack polling web application featuring JWT authentication, real-time voting, dynamic result visualization, comments, likes, view counting, and a fully responsive Material UI design.

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✨ Features

• 🔐 User Authentication — Secure registration and login with JWT (JSON Web Tokens) & BCrypt password hashing.
• 📊 Interactive Polls — Create polls with custom options and expiration dates.
• 🗳️ Real-Time Voting — Enforces one vote per user per poll with instant tallying.
• 📈 Dynamic Results — Visual progress bars with automated percentage calculations.
• 💬 Comments System — Engage in discussions under polls with instant updates.
• ❤️ Likes & Views Tracking — Like/unlike toggle mechanism and poll view analytics.
• 👤 User Dashboard ("My Polls") — View, manage, and delete polls created by the logged-in user.
• ⏳ Expiration Handling — Auto-closes polls upon reaching expiration time with distinct UI badges.
• 📱 Responsive UI — Built with Material UI 5 with support for mobile, tablet, and desktop viewports.

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🛠️ Tech Stack

Layer	Technology	Details
Frontend	React 18, Vite 5, JavaScript (ES6+)	Single Page Application (SPA)
UI Framework	Material UI (MUI v5), Emotion, Notistack	Modern responsive design & notification toasts
HTTP Client	Axios	Configured with automatic JWT request/response interceptors
Backend	Java 17 / 21, Spring Boot 3.2.5	RESTful API built with Spring Data JPA & Hibernate
Security	Spring Security 6, JJWT (0.12.5)	Stateless authentication & BCrypt password hashing
Database	PostgreSQL (Neon Cloud) / H2 (Local)	Production cloud DB & fast zero-setup local DB
Containerization	Multi-stage Docker (Dockerfile)	Monolithic container embedding React build into Spring Boot
Deployment	Render	Hosted full-stack web service

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🏗️ Architecture

  Client Browser (HTTPS)
          │
          ▼
  Spring Boot Service (Render / Docker on Port 8080)
  ├── 🌐 Serves React Static UI (/src/main/resources/static)
  └── 🔌 Exposes REST API (/api/**)
          │
          │ JPA / Hibernate (PostgreSQL Connection)
          ▼
  Neon Cloud PostgreSQL Database

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📁 Project Structure

PollingApp/
├── backend/                             # Spring Boot Backend
│   ├── pom.xml                          # Maven dependencies & plugins
│   ├── .env.example                     # Backend environment template
│   └── src/
│       ├── main/
│       │   ├── java/com/pollingapp/
│       │   │   ├── config/              # Security, CORS & Web forwarder config
│       │   │   ├── controller/          # REST API endpoints (Auth, Poll, Comment, Vote)
│       │   │   ├── dto/                 # Request & Response DTOs
│       │   │   ├── entity/              # JPA Entities (User, Poll, Option, Vote, Comment)
│       │   │   ├── exception/           # Custom exceptions & global exception handler
│       │   │   ├── repository/          # Spring Data JPA repositories
│       │   │   ├── security/            # JWT Token provider, filter & UserDetailsService
│       │   │   └── service/             # Business logic implementations
│       │   └── resources/
│       │       ├── application.properties        # Production PostgreSQL configuration
│       │       └── application-local.properties  # Local in-memory H2 profile
│       └── test/                        # Integration and unit tests
├── frontend/                            # React + Vite Frontend
│   ├── package.json                     # Frontend dependencies & scripts
│   ├── vite.config.js                   # Vite configuration
│   ├── .env.example                     # Frontend environment template
│   ├── index.html                       # HTML entry point
│   └── src/
│       ├── components/                  # UI components (Navbar, PollCard, ProtectedRoute)
│       ├── pages/                       # Pages (Dashboard, CreatePoll, Login, Register, MyPolls)
│       ├── services/                    # API services (authService, pollService)
│       └── utils/                       # JWT token & auth helpers
├── Dockerfile                           # Multi-stage Docker build (React + Spring Boot combined)
├── API.md                               # Complete REST API documentation
├── LICENSE                              # MIT License
├── README.md                            # Project documentation
└── .gitignore                           # Git ignore rules

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⚙️ Environment Variables

Backend (Render Environment Variables / backend/.env)

Variable	Description	Example
SPRING_DATASOURCE_URL	PostgreSQL JDBC Connection URL	jdbc:postgresql://<host>:5432/<dbname>?sslmode=require
SPRING_DATASOURCE_USERNAME	Database username	<neon-username>
SPRING_DATASOURCE_PASSWORD	Database password	<neon-password>
SPRING_DATASOURCE_DRIVER_CLASS_NAME	PostgreSQL driver	org.postgresql.Driver
JWT_SECRET	Secret key for JWT token signing	yourSecretKeyForPollingAppThatIsLongEnough123
JWT_EXPIRATION	Token expiration time (ms)	86400000 (24 hours)

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🚀 Local Development Setup

Prerequisites

• Java JDK 17 or 21: Download Adoptium
• Maven 3.8+: Download Maven
• Node.js 18+ & npm: Download Node.js
• Git: Download Git

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1. Clone the Repository

git clone https://github.com/prabhakar111ji/PollingApp.git
cd PollingApp

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2. Run Backend (with Local H2 In-Memory DB)

cd backend
mvn spring-boot:run -Dspring-boot.run.profiles=local

• Backend API: http://localhost:8080/api
• H2 Database Console: http://localhost:8080/h2-console (JDBC URL: jdbc:h2:mem:poll_db, User: sa, Password: empty)

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3. Run Frontend

cd frontend
npm install
npm run dev

• Frontend App: http://localhost:5173

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🌐 Production Deployment (Render + Neon PostgreSQL)

The project uses a monolithic multi-stage Dockerfile that builds both the React frontend and Spring Boot backend into a single container:

1. Database (Neon):

   • Create a free PostgreSQL database on Neon.tech.
   • Copy the PostgreSQL connection credentials.

2. Web Service (Render):

   • Create a new Web Service on Render.com and connect this repository.
   • Choose runtime Docker and branch main.
   • Under Environment Variables, set:
     • SPRING_DATASOURCE_URL = jdbc:postgresql://<neon-host>:5432/<dbname>?sslmode=require
     • SPRING_DATASOURCE_USERNAME = <your-neon-username>
     • SPRING_DATASOURCE_PASSWORD = <your-neon-password>
     • SPRING_DATASOURCE_DRIVER_CLASS_NAME = org.postgresql.Driver
     • JWT_SECRET = yourRandomSecretKey
   • Click Deploy Web Service.

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📖 API Documentation

Complete REST API specifications and request/response payloads: 👉 View Complete API Documentation (API.md)

Key Endpoints:

• POST /api/auth/signup — Register a new account
• POST /api/auth/login — Login and receive JWT token
• GET /api/user/poll — Fetch all polls
• POST /api/user/poll — Create a new poll (Authenticated)
• GET /api/user/poll/{id} — Get single poll details with comments
• GET /api/user/poll/my — Get user's created polls (Authenticated)
• DELETE /api/user/poll/{id} — Delete a poll by ID (Owner only)
• POST /api/user/poll/vote — Cast a vote (Authenticated)
• POST /api/user/poll/{id}/like — Toggle like/unlike (Authenticated)
• POST /api/user/poll/comment — Add comment (Authenticated)
• GET /api/health — Backend health check

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🛡️ License

This project is open-source and available under the MIT License.