Collaborative painting on a canvas over the network, using socket.io.

Mouse + touch supported.
Legacy browsers not supported.

• Reverse Proxy: Caddy 2 https://caddyserver.com/
• Backend: Node.js 14 (version 12 probably also works)
• Messaging: https://socket.io/
• Server: https://github.com/expressjs/express
• UI: https://github.com/hustcc/timeago.js

$ ./npm-ci.sh

Start the backend server (frontend included):

$ cd backend
backend$ npm start

Afterwards, open http://localhost:42024 to enter the "lobby".
Open the website in multiple tabs to simulate multiple users.

Preparations (once):

• Sign up for Heroku free tier.
• Install Heroku CLI.
• Clone this repo.
• heroku create YOUR_APP_NAME (once)

(Re-)Deploy:

• ./heroku-deploy.sh --login
  (Option --login is probably only needed for first run.)
  (See script source for options to configure the app.)
• Browser should open automatically; if not, open: https://YOUR_APP_NAME.herokuapp.com/

If you want to run the app on your "own" server.

• Register your internet domain: DOMAIN (e.g. example.com).
  Replace DOMAIN with your custom domain everywhere below.
• Start a server, e.g. on EC2.
  Make sure that ports 80 + 443 are publicly available for requesting an HTTPS certificate using ACME (Let's Encrypt).
• Add A and/or AAAA DNS records for DOMAIN and *.DOMAIN (or backend.DOMAIN).
• Install Node.js 12.
• Install Caddy 2 (used as reverse proxy): https://caddyserver.com/docs/download
  (Use one of the package manager options, if available for your distribution.)
• Clone the Git repo on the server.
• ./npm-ci.sh
• ./run.sh DOMAIN
  (Press Ctrl-C to exit.)
• Open the website https://DOMAIN in your browser.
  Authenticate using the dummy credentials user and password. (To disable authentication, remove the basicauth block from proxy/Caddyfile.)
  If you get a TLS error, then probably Let's Encrypt can't access your server. Look at the Caddy console output for details.