A script to detect user game changes and apply valid roles

app.js

var Discord = require('discord.js');

var discordBotToken = 'YOUR BOT TOKEN HERE';
var prefix = 'vores_';

var roleGame = {
  "blackdesert": {
    name: "black desert online",
    id: ''
  },
  "lol": {
    name: "league of legends",
    id: ''
  }
};

var client = new Discord.Client();

function collectRoleIds() {
  client.guilds.forEach( function(server) {
    server.roles.forEach( function(role) {
      for (var gKey in roleGame) {
        if (prefix + gKey === role.name) {
          roleGame[gKey]['id'] = role.id;
        }
      }
    });
  });
}

function registeredGame(game) {
  for (var gKey in roleGame) {
    if ((game !== null && game.name !== undefined) && roleGame[gKey].name === game.name.toLowerCase()) {
      return gKey;
    }
  }

  return false;
}

client.on('message', msg => {
  if ((msg.mentions.users.get(client.user.id) || !msg.channel.server) && msg.author !== client.user) {
    var message = 'Supported Games (game / id):';

    for (var gKey in roleGame) {
      message += '\r\n' + roleGame[gKey].name + '/' + prefix + gKey;
    }

    msg.reply(message);
  }
});

client.on('presenceUpdate', (oldUser, newUser) => {
  if (oldUser.presence.game !== newUser.presence.game) {
    if (oldUser.presence.game !== null && oldUser.presence.game !== null) {
      var oldGame = registeredGame(oldUser.presence.game);
      if (oldGame) {
        newUser.removeRole(roleGame[oldGame].id, function (error) {
          if (error) console.log(error);
        });
      }
    }

    if (newUser.presence !== null && newUser.presence.game !== null) {
      var gameId = registeredGame(newUser.presence.game);
      if (gameId) {
        newUser.addRole(roleGame[gameId].id, function (error) {
          if (error) console.log(error);
        });
        console.log(gameId);
      }
    }
  }
});

client.on('ready', () => {
  console.log('Bot serving. Setting status...');
  client.user.setStatus('online');
  client.user.setGame('Beating Down Chumps');

  collectRoleIds();
});

client.login(discordBotToken);

i found this from reddit. I wonder if what is ID in the very first line ?