VoteFlow

A minimal, self-contained voting system. Create polls, share them, and watch the results update in real time. Ships with an in-memory demo mode so it runs with zero configuration, and an optional Prisma database for persistence.

• Backend: Node.js + Express 5
• Database (optional): Prisma (SQLite locally, PostgreSQL for production)
• Frontend: Vue 3 (CDN) + Tailwind CSS (CDN), served from public/
• Deploy: Vercel (serverless)

Features

• Create polls with two or more options (admin only)
• One vote per poll per voter (tracked by an anonymous local voter id)
• Live percentage results with a highlighted winner
• Admin login via x-admin-key to create/delete polls
• Automatic demo mode with sample data when no database is configured

Project structure

api/index.js       Vercel serverless entrypoint
lib/app.js         Express app (routes + store resolution)
server.js          Local development server
store.js           Prisma and in-memory store implementations
prisma/            Schema and migrations
public/index.html  Vue + Tailwind single-page UI
vercel.json        Routes /api/* to the serverless function

Local development

npm install
cp .env.example .env      # optional
npm start                 # http://localhost:3000

Run without a database and VoteFlow starts in demo mode with sample polls that reset on restart. The demo admin key is whatever ADMIN_KEY is set to (default admin).

Using a database locally

1. Set DATABASE_URL in .env (see .env.example).
2. Apply migrations and start:

npx prisma migrate deploy
npm start

SQLite example: DATABASE_URL="file:./dev.db".

Deploying to Vercel

1. Push this repo to GitHub/GitLab and import it at vercel.com/new, or run npx vercel from the project root.
2. Set environment variables in Project → Settings → Environment Variables:
   • ADMIN_KEY — your admin password (required in production).
   • DATABASE_URL — optional, see below.
3. Deploy. Vercel builds api/index.js as a single serverless function and serves public/ from its CDN.

vercel.json routes every /api/* request to the function; static files in public/ are served directly by the CDN.

Database on Vercel

Serverless functions are ephemeral, so:

• Without DATABASE_URL the app runs in demo mode. Data resets on every cold start and is not shared between instances.

• SQLite does not work on Vercel (read-only, non-persistent filesystem). Use a hosted PostgreSQL database such as Neon or Supabase, then:

  1. Change the datasource provider in prisma/schema.prisma to postgresql:

     datasource db {
       provider = "postgresql"
       url      = env("DATABASE_URL")
     }

  2. Point DATABASE_URL at your Postgres instance.
  3. Run the migration against it (locally, with the same URL in your env):

     npx prisma migrate deploy

postinstall runs prisma generate automatically during the Vercel build.

Environment variables

Variable	Required	Description
ADMIN_KEY	No*	Admin password. Defaults to admin.
DATABASE_URL	No	Database connection string. Omit to run in demo mode.
PORT	No	Local server port. Defaults to 3000. Not used on Vercel.

* Strongly recommended in production.

API

All endpoints return JSON. Admin endpoints require an x-admin-key header.

Method	Path	Auth	Description
GET	/api/mode	—	Current mode (demo/database)
POST	/api/admin/login	—	Validate the admin key
GET	/api/polls	—	List polls
GET	/api/polls/:id	—	Poll detail with results
POST	/api/polls	Admin	Create a poll
POST	/api/polls/:id/vote	—	Cast a vote
DELETE	/api/polls/:id	Admin	Delete a poll

Example:

curl -X POST localhost:3000/api/polls \
  -H "x-admin-key: admin" -H "Content-Type: application/json" \
  -d '{"question":"Tabs or spaces?","options":["Tabs","Spaces"]}'

License

ISC