How can I notify my discord bot of some client event?

Question

JavaScript

The task is this: the Discord bot, when pressing a key on the keyboard on the user's computer (the creator of the discord server), must do something (in my case, include a specific .mp3 file).
I have an application that listens for a specific key being pressed (using the iohook module):

const ioHook = require('iohook');
ioHook.on("keypress", event => {
  // Numpad 0
  if(event.rawcode === 96) {
    
  }
});

ioHook.start();

How can I notify my discord bot that a key has been pressed on the client and the bot needs to execute a certain command?
There is an option with websockets, but it seems to me that this will not be very optimized, so I thought that
node-fetch could be used, but I do not quite understand where I should send the request.
The bot, if anything, is on Heroku.