Buzzer

Your phone is now an Internet-connected gameshow buzzer.

Tech

Uses a Node.js backend with Express and Socket.io to manage the players' connections.

Setup

With Docker

Create the image either with make build, docker build -t buzzer_app . or docker-compose build.

Run with docker run -it --rm -p 8080:8080 -v ./message/:/usr/src/app/message/ buzzer_app or docker-compose up.

Without Docker

Requires Node.js and NPM to be installed. This has been built and tested with Node 16.

npm install to install the dependencies, then npm start to run. It will listen on port 8080.

Testing

Behaviour tests have been written for the basic functionality of the app.

First, run the app with npm start, then in a separate terminal, run npm run test.

Deployment

If the machine you're building on isn't the one you want to run the app on, make a Docker-deployable zip file with make zip or docker save buzzer_app | gzip > buzzer.tar.gz. Send the zip file to the server.

On the server, run docker load < buzzer.tar.gz. The app can then be run using docker-compose or similar.

Nginx configuration

Your webserver should be configured to enable websocket connections, otherwise clients will revert to the fallback method of long-polling HTTP requests.

Using Nginx configuration as an example, be sure to add a location block that upgrades socket.io connections.

server {
    server_name _;
    location / {
        proxy_pass http://127.0.0.1:8080;
    }
    location /socket.io/ {
        proxy_pass http://127.0.0.1:8080;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "Upgrade";
        proxy_set_header Host $host;
    }

    listen 80;
}

Configuration adapted from the Nginx blog.

Broadcast message

To send a message to all connected players (e.g. to warn of upcoming maintenance), edit the file message/message.txt. It will be sent to all players within a minute.

Donations

I'd like this app to remain free for everyone. If you've found Buzzer useful and you'd like to contribute to the hosting costs, you can Buy Me a Coffee.

Contributing

Bugfix PRs are welcomed, and new features may be accepted, but before you go and spend lots of time working on them, you should raise an issue first.