discord.js/packages/voice/examples/basic/basic-example.ts

import { Client, VoiceBasedChannel, VoiceChannel } from 'discord.js';
import {
	joinVoiceChannel,
	createAudioPlayer,
	createAudioResource,
	entersState,
	StreamType,
	AudioPlayerStatus,
	VoiceConnectionStatus,
} from '@discordjs/voice';
import { createDiscordJSAdapter } from './adapter';
import { GatewayIntentBits } from 'discord-api-types/v9';

/**
 * 	In this example, we are creating a single audio player that plays to a number of voice channels.
 * The audio player will play a single track.
 */

/**
 * Create the audio player. We will use this for all of our connections.
 */
const player = createAudioPlayer();

function playSong() {
	/**
	 * Here we are creating an audio resource using a sample song freely available online
	 * (see https://www.soundhelix.com/audio-examples)
	 *
	 * We specify an arbitrary inputType. This means that we aren't too sure what the format of
	 * the input is, and that we'd like to have this converted into a format we can use. If we
	 * were using an Ogg or WebM source, then we could change this value. However, for now we
	 * will leave this as arbitrary.
	 */
	const resource = createAudioResource('https://www.soundhelix.com/examples/mp3/SoundHelix-Song-1.mp3', {
		inputType: StreamType.Arbitrary,
	});

	/**
	 * We will now play this to the audio player. By default, the audio player will not play until
	 * at least one voice connection is subscribed to it, so it is fine to attach our resource to the
	 * audio player this early.
	 */
	player.play(resource);

	/**
	 * Here we are using a helper function. It will resolve if the player enters the Playing
	 * state within 5 seconds, otherwise it will reject with an error.
	 */
	return entersState(player, AudioPlayerStatus.Playing, 5e3);
}

async function connectToChannel(channel: VoiceBasedChannel) {
	/**
	 * Here, we try to establish a connection to a voice channel. If we're already connected
	 * to this voice channel, @discordjs/voice will just return the existing connection for us!
	 */
	const connection = joinVoiceChannel({
		channelId: channel.id,
		guildId: channel.guild.id,
		adapterCreator: createDiscordJSAdapter(channel),
	});

	/**
	 * If we're dealing with a connection that isn't yet Ready, we can set a reasonable
	 * time limit before giving up. In this example, we give the voice connection 30 seconds
	 * to enter the ready state before giving up.
	 */
	try {
		/**
		 * Allow ourselves 30 seconds to join the voice channel. If we do not join within then,
		 * an error is thrown.
		 */
		await entersState(connection, VoiceConnectionStatus.Ready, 30e3);
		/**
		 * At this point, the voice connection is ready within 30 seconds! This means we can
		 * start playing audio in the voice channel. We return the connection so it can be
		 * used by the caller.
		 */
		return connection;
	} catch (error) {
		/**
		 * At this point, the voice connection has not entered the Ready state. We should make
		 * sure to destroy it, and propagate the error by throwing it, so that the calling function
		 * is aware that we failed to connect to the channel.
		 */
		connection.destroy();
		throw error;
	}
}

/**
 * Main code
 * =========
 * Here we will implement the helper functions that we have defined above.
 */

const client = new Client({
	intents: [GatewayIntentBits.Guilds, GatewayIntentBits.GuildMessages, GatewayIntentBits.GuildVoiceStates],
});

void client.login('token here');

client.on('ready', async () => {
	console.log('Discord.js client is ready!');

	/**
	 * Try to get our song ready to play for when the bot joins a voice channel
	 */
	try {
		await playSong();
		console.log('Song is ready to play!');
	} catch (error) {
		/**
		 * The song isn't ready to play for some reason :(
		 */
		console.error(error);
	}
});

client.on('messageCreate', async (message) => {
	if (!message.guild) return;

	if (message.content === '-join') {
		const channel = message.member?.voice.channel;

		if (channel) {
			/**
			 * The user is in a voice channel, try to connect.
			 */
			try {
				const connection = await connectToChannel(channel);

				/**
				 * We have successfully connected! Now we can subscribe our connection to
				 * the player. This means that the player will play audio in the user's
				 * voice channel.
				 */
				connection.subscribe(player);
				await message.reply('Playing now!');
			} catch (error) {
				/**
				 * Unable to connect to the voice channel within 30 seconds :(
				 */
				console.error(error);
			}
		} else {
			/**
			 * The user is not in a voice channel.
			 */
			void message.reply('Join a voice channel then try again!');
		}
	}
});