Poll App

A simple single-page poll application. Users create a poll, get a short link, share it, and vote. Results appear immediately after voting.

Stack

• Backend: Laravel 11 (PHP), SQLite, DDD + Clean Architecture
• Frontend: Vue 3, Vuex, Vue Router, Axios, Vite

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Project Structure

/
├── backend/    # Laravel API
└── frontend/   # Vue 3 SPA

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Setup & Launch

Prerequisites

• PHP >= 8.2
• Composer
• Node.js >= 18
• npm

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Backend

cd backend

# 1. Install PHP dependencies
composer install

# 2. Copy environment file (already configured for SQLite)
cp .env.example .env

# 3. Generate app key
php artisan key:generate

# 4. Run migrations (creates polls, options, votes tables)
php artisan migrate

# 5. Start the development server
php artisan serve

The API will be available at http://localhost:8000.

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Frontend

cd frontend

# 1. Install dependencies
npm install

# 2. Start the dev server
npm run dev

The app will be available at http://localhost:5173.

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API Endpoints

Method	URL	Description
POST	/api/polls	Create a poll
GET	/api/polls/{short_code}	Get poll data (+ voted status by IP)
POST	/api/polls/{short_code}/vote	Cast a vote

POST /api/polls

{
  "title": "Favorite color?",
  "options": ["Red", "Blue", "Green"]
}

Response 201:

{ "short_code": "aBc123" }

POST /api/polls/{short_code}/vote

{ "option_id": 2 }

Response 200:

{
  "votes": [
    { "option_id": 1, "option": "Red", "count": 3 },
    { "option_id": 2, "option": "Blue", "count": 5 }
  ]
}

Returns 409 Conflict if the IP has already voted.

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Architecture Notes

Backend (DDD / Clean Architecture)

app/
├── Domain/Poll/
│   ├── Contracts/CodeGeneratorInterface.php   # Strategy interface for code generation
│   ├── Services/RandomCodeGenerator.php       # Default implementation
│   └── Factories/PollFactory.php              # Domain factory (injectable strategy)
├── Application/Poll/UseCases/
│   ├── CreatePollUseCase.php
│   ├── GetPollUseCase.php
│   └── VoteUseCase.php
├── Http/Controllers/Api/PollController.php
├── Http/Requests/
│   ├── CreatePollRequest.php
│   └── VoteRequest.php
└── Providers/PollServiceProvider.php          # Binds interface to implementation

Swapping the code generation strategy — inject a different CodeGeneratorInterface implementation via PollServiceProvider:

// e.g. bind a custom NanoIdGenerator instead
$this->app->bind(CodeGeneratorInterface::class, NanoIdGenerator::class);

Frontend (Vue 3)

src/
├── api/index.js          # Axios instance
├── store/index.js        # Vuex store (poll, results, hasVoted)
├── router/index.js       # /create and /poll/:code routes
├── views/
│   ├── CreatePoll.vue    # Poll creation form
│   └── PollPage.vue      # Voting / results page
└── components/
    ├── VoteForm.vue      # Radio options + submit
    └── PollResults.vue   # Results with bar chart

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Duplicate Vote Protection

Votes are deduplicated by (poll_id, ip_address) unique constraint in the database. A repeat vote returns 409 Conflict. On page load, the backend checks the IP and returns results immediately if already voted.