Files
Discord-Audio-Stream/src/audio-manager.ts
T

426 lines
14 KiB
TypeScript

import type { AudioPlayer, AudioResource, VoiceConnection } from '@discordjs/voice';
import {
createAudioPlayer,
createAudioResource,
entersState,
joinVoiceChannel,
AudioPlayerStatus,
NoSubscriberBehavior,
StreamType,
VoiceConnectionStatus,
} from '@discordjs/voice';
import { isAbsolute, resolve } from 'node:path';
import { AudioManagerConfigError, AudioManagerStateError } from './errors';
import { startFfmpeg, type FfmpegProcessHandle } from './ffmpeg';
import type {
AudioManagerOptions,
AudioSource,
PlaybackState,
ResolvedAudioSource,
VoiceConnectionOptions,
} from './types';
const DEFAULT_CONNECT_TIMEOUT_MS = 20_000;
const DISCONNECT_RECOVERY_TIMEOUT_MS = 5_000;
const MAX_TIMER_DELAY_MS = 2_147_483_647;
function assertValidTimerDelay(value: number, optionName: string): void {
if (!Number.isSafeInteger(value) || value <= 0 || value > MAX_TIMER_DELAY_MS) {
throw new AudioManagerConfigError(
`${optionName} must be an integer between 1 and ${MAX_TIMER_DELAY_MS} milliseconds.`,
);
}
}
function assertValidVolumePercent(value: number): void {
if (!Number.isFinite(value) || value < 0 || value > 100) {
throw new AudioManagerConfigError('Volume must be between 0 and 100 percent.');
}
}
export default class AudioManager implements Disposable {
private readonly audioPlayer: AudioPlayer;
private connection: VoiceConnection | undefined;
private resource: AudioResource | undefined;
private ffmpeg: FfmpegProcessHandle | undefined;
private connectAttempt: AbortController | undefined;
private renewTimer: NodeJS.Timeout | undefined;
private playbackState: PlaybackState = 'idle';
private connectionOptions: VoiceConnectionOptions | undefined;
private audioSource: AudioSource | undefined;
private readonly options: Required<Pick<AudioManagerOptions, 'connectTimeoutMs'>> &
Omit<AudioManagerOptions, 'connectTimeoutMs'>;
public constructor(options: AudioManagerOptions = {}) {
const connectTimeoutMs = options.connectTimeoutMs ?? DEFAULT_CONNECT_TIMEOUT_MS;
assertValidTimerDelay(connectTimeoutMs, 'connectTimeoutMs');
if (typeof options.renewIntervalMs === 'number') {
assertValidTimerDelay(options.renewIntervalMs, 'renewIntervalMs');
}
if (options.volume?.initialPercent !== undefined) {
if (options.volume.enabled !== true) {
throw new AudioManagerConfigError('volume.initialPercent requires volume.enabled to be true.');
}
assertValidVolumePercent(options.volume.initialPercent);
}
this.options = {
...options,
connectTimeoutMs,
};
this.connectionOptions = options.connection;
this.audioSource = options.source;
this.audioPlayer = createAudioPlayer({
behaviors: {
noSubscriber: NoSubscriberBehavior.Play,
},
});
this.audioPlayer.on('error', (error) => {
this.finishPlayback(error.resource);
this.reportError(error);
});
this.audioPlayer.on(AudioPlayerStatus.Idle, (oldState) => {
if ('resource' in oldState) {
this.finishPlayback(oldState.resource);
}
});
}
public get state(): PlaybackState {
return this.playbackState;
}
public get isPlaying(): boolean {
return this.playbackState === 'playing';
}
public get isConnected(): boolean {
return this.connection?.state.status === VoiceConnectionStatus.Ready;
}
public setConnection(options: VoiceConnectionOptions): void {
this.assertNotDisposed();
this.connectionOptions = options;
}
public setSource(source: AudioSource): void {
this.assertNotDisposed();
this.audioSource = source;
}
public async connect(): Promise<void> {
this.assertNotDisposed();
if (!this.connectionOptions) {
throw new AudioManagerConfigError('Voice connection options are required before connecting.');
}
this.cancelConnectAttempt();
const attempt = new AbortController();
this.connectAttempt = attempt;
this.clearRenewTimer();
this.playbackState = 'connecting';
const previousConnection = this.connection;
this.connection = undefined;
let connection: VoiceConnection | undefined;
try {
previousConnection?.destroy();
connection = joinVoiceChannel({
guildId: this.connectionOptions.guildId,
channelId: this.connectionOptions.channelId,
adapterCreator: this.connectionOptions.adapterCreator,
});
this.connection = connection;
this.observeConnection(connection);
connection.subscribe(this.audioPlayer);
await entersState(
connection,
VoiceConnectionStatus.Ready,
AbortSignal.any([attempt.signal, AbortSignal.timeout(this.options.connectTimeoutMs)]),
);
} catch (error) {
if (this.connectAttempt !== attempt) {
throw new AudioManagerStateError('Voice connection was stopped before it became ready.', {
cause: error,
});
}
this.connectAttempt = undefined;
if (connection && connection.state.status !== VoiceConnectionStatus.Destroyed) {
connection.destroy();
}
if (this.connection === connection) {
this.connection = undefined;
}
this.playbackState = 'stopped';
throw error;
}
if (this.connectAttempt !== attempt || this.connection !== connection) {
throw new AudioManagerStateError('Voice connection was stopped before it became ready.');
}
this.connectAttempt = undefined;
this.playbackState = 'ready';
this.scheduleRenewal();
}
public async play(source?: AudioSource): Promise<void> {
this.assertNotDisposed();
if (source) {
this.setSource(source);
}
if (!this.isConnected) {
throw new AudioManagerStateError('A voice connection is required before audio can be played.');
}
const resolvedSource = this.resolveSource();
this.stopCurrentPlayback();
this.ffmpeg = startFfmpeg(resolvedSource.input, this.options.ffmpeg);
const ffmpeg = this.ffmpeg;
try {
await ffmpeg.ready;
if (this.ffmpeg !== ffmpeg) {
throw new AudioManagerStateError('Playback was stopped before ffmpeg became ready.');
}
this.resource = createAudioResource(ffmpeg.process.stdout, {
inputType: StreamType.Raw,
inlineVolume: this.options.volume?.enabled === true,
});
} catch (error) {
if (this.ffmpeg !== ffmpeg) {
throw error instanceof AudioManagerStateError
? error
: new AudioManagerStateError('Playback was stopped before ffmpeg became ready.', {
cause: error,
});
}
this.stopCurrentPlayback();
throw error;
}
try {
if (this.options.volume?.enabled === true && this.options.volume.initialPercent !== undefined) {
this.setVolume(this.options.volume.initialPercent);
}
this.audioPlayer.play(this.resource);
this.playbackState = 'playing';
} catch (error) {
this.stopCurrentPlayback();
this.playbackState = 'ready';
throw error;
}
}
public async start(): Promise<void> {
await this.connect();
await this.play();
}
public pause(): void {
this.assertNotDisposed();
if (this.playbackState !== 'playing') {
throw new AudioManagerStateError('Audio can only be paused while it is playing.');
}
this.audioPlayer.pause();
this.playbackState = 'paused';
}
public resume(): void {
this.assertNotDisposed();
if (this.playbackState !== 'paused') {
throw new AudioManagerStateError('Audio can only be resumed while it is paused.');
}
this.audioPlayer.unpause();
this.playbackState = 'playing';
}
public async stop(): Promise<void> {
if (this.playbackState === 'disposed') {
return;
}
this.cancelConnectAttempt();
this.clearRenewTimer();
this.stopCurrentPlayback();
this.audioPlayer.stop(true);
this.connection?.disconnect();
this.connection?.destroy();
this.connection = undefined;
this.playbackState = 'stopped';
}
public setVolume(volumeInPercent: number): void {
this.assertNotDisposed();
if (this.options.volume?.enabled !== true) {
throw new AudioManagerStateError('Volume control requires volume.enabled to be true.');
}
assertValidVolumePercent(volumeInPercent);
if (!this.resource?.volume) {
throw new AudioManagerStateError('No audio resource with volume control is currently active.');
}
this.resource.volume.setVolume(volumeInPercent / 100);
}
public dispose(): void {
if (this.playbackState === 'disposed') {
return;
}
this.cancelConnectAttempt();
this.clearRenewTimer();
this.stopCurrentPlayback();
this.audioPlayer.stop(true);
this.connection?.destroy();
this.connection = undefined;
this.connectionOptions = undefined;
this.audioSource = undefined;
this.playbackState = 'disposed';
}
public [Symbol.dispose](): void {
this.dispose();
}
private resolveSource(): ResolvedAudioSource {
if (!this.audioSource) {
throw new AudioManagerConfigError('Audio source is required before playback can start.');
}
if (this.audioSource.type === 'url') {
try {
return {
input: new URL(this.audioSource.url).toString(),
source: this.audioSource,
};
} catch (error) {
throw new AudioManagerConfigError('Invalid audio source URL.', { cause: error });
}
}
return {
input: isAbsolute(this.audioSource.path)
? this.audioSource.path
: resolve(process.cwd(), this.audioSource.path),
source: this.audioSource,
};
}
private scheduleRenewal(): void {
const renewIntervalMs = this.options.renewIntervalMs;
if (renewIntervalMs === undefined || renewIntervalMs === false) {
return;
}
this.renewTimer = setTimeout(() => {
void this.start().catch((error: unknown) => {
if (this.playbackState === 'disposed') {
return;
}
this.clearRenewTimer();
this.stopCurrentPlayback();
this.audioPlayer.stop(true);
this.connection?.disconnect();
this.connection?.destroy();
this.connection = undefined;
this.playbackState = 'stopped';
this.reportError(error);
});
}, renewIntervalMs);
if (typeof this.renewTimer.unref === 'function') {
this.renewTimer.unref();
}
}
private observeConnection(connection: VoiceConnection): void {
connection.on('error', (error) => {
this.reportError(error);
});
connection.on(VoiceConnectionStatus.Disconnected, () => this.handleDisconnectedConnection(connection));
}
private async handleDisconnectedConnection(connection: VoiceConnection): Promise<void> {
try {
await Promise.race([
entersState(connection, VoiceConnectionStatus.Signalling, DISCONNECT_RECOVERY_TIMEOUT_MS),
entersState(connection, VoiceConnectionStatus.Connecting, DISCONNECT_RECOVERY_TIMEOUT_MS),
]);
} catch (error) {
if (this.connection !== connection) {
return;
}
this.clearRenewTimer();
this.stopCurrentPlayback();
this.audioPlayer.stop(true);
this.connection = undefined;
if (connection.state.status !== VoiceConnectionStatus.Destroyed) {
connection.destroy();
}
this.playbackState = 'stopped';
this.reportError(error);
}
}
private finishPlayback(resource: AudioResource): void {
if (this.resource !== resource) {
return;
}
this.stopCurrentPlayback();
if (this.playbackState !== 'disposed') {
this.playbackState = this.isConnected ? 'ready' : 'stopped';
}
}
private reportError(error: unknown): void {
this.options.onError?.(error instanceof Error ? error : new Error(String(error)));
}
private clearRenewTimer(): void {
if (this.renewTimer) {
clearTimeout(this.renewTimer);
this.renewTimer = undefined;
}
}
private cancelConnectAttempt(): void {
this.connectAttempt?.abort();
this.connectAttempt = undefined;
}
private stopCurrentPlayback(): void {
this.resource?.playStream.destroy();
this.resource = undefined;
this.ffmpeg?.stop();
this.ffmpeg = undefined;
}
private assertNotDisposed(): void {
if (this.playbackState === 'disposed') {
throw new AudioManagerStateError('AudioManager has been disposed.');
}
}
}