count-the-things-multiplayer

A simple websocket app for multiple people to count things together. Created to track occupancy at a Farmer's Market with multiple entrances and exits.

For a "single player" variant, see the static version of this project.

Local Environment Setup

Prerequisites

You'll need a Redis server running on your development machine. Follow the installation steps outlined in the Redis Quick Start Guide, abbreviated here:

curl -O http://download.redis.io/redis-stable.tar.gz
tar xvzf redis-stable.tar.gz
cd redis-stable
make
sudo make install

Then, start the redis server:

$ redis-server

Setup

npm install
npm run start

Then visit http://localhost:8765 in your web browser of choice.

Testing with Multiple Client Devices

I recommend using ngrok for this use case, which publicly exposes your local web server via a network tunnel:

npm install ngrok -g
ngrok http 8765 # after starting the application

Your terminal should display a public URL for all client devices to connect to.

Given the ephemeral nature of ngrok urls, it is impractical to whitelist them in the app's Content Security Policy headers. While testing with ngrok, it may be necessary to temporarily disable the CSP by commenting out the expressCspHeader config in app/index.js.

For obvious reasons, one should not leave the CSP disabled on a permanent production deployment.