How do I disconnect the bot when the user that summoned it leaves?

Question

I have created a discord bot that follows users around vc's and joins them, how do I disconnect the audio stream when they leave? Code is as follows:

client.on('voiceStateUpdate', (oldMember, newMember) => {
  console.log(newMember.channelID)
 
  let newUserChannel = newMember.channelID;
  const channel = client.channels.cache.get(newUserChannel);
  
  channel.join().then(connection => {
      const dispatcher = connection.play('audio.mp3',{ volume: 1 });

      dispatcher.on('start', () => {
        console.log('audio.mp3 is now playing!');
      });
  
      dispatcher.on('finish', () => {
        console.log('audio.mp3 has finished playing!');
        connection.disconnect();
      });
      // Always remember to handle errors appropriately!
    }).catch(e => {
        console.error(e);
    });
  }
);

Answer 1

Just add an if statement to your code, which checks if there is still one Discord user in the channel (except the bot). If not, disconnect:

if (oldMember.channel.members.size === 1) {
      connection.disconnect();
}