Class: SapphireClient<Ready>

The base {@link Client} extension that makes Sapphire work. When building a Discord bot with the framework, the developer must either use this class, or extend it.

Sapphire also automatically detects the folders to scan for pieces, please read StoreRegistry.registerPath for reference. This method is called at the start of the SapphireClient.login method.

see SapphireClientOptions for all options available to the Sapphire Client. You can also provide all of discord.js' ClientOptions

since 1.0.0

example

const client = new SapphireClient({
  presence: {
    activity: {
      name: 'for commands!',
      type: 'LISTENING'
    }
  }
});

client.login(process.env.DISCORD_TOKEN)
  .catch(console.error);

example

// Automatically scan from a specific directory, e.g. the main
// file is at `/home/me/bot/index.js` and all your pieces are at
// `/home/me/bot/pieces` (e.g. `/home/me/bot/pieces/commands/MyCommand.js`):
const client = new SapphireClient({
  baseUserDirectory: join(__dirname, 'pieces'),
  // More options...
});

example

// Opt-out automatic scanning:
const client = new SapphireClient({
  baseUserDirectory: null,
  // More options...
});

Type parameters

Name	Type
`Ready`	extends `boolean` = `boolean`

Hierarchy

Client<Ready>
↳ SapphireClient

Constructors

constructor

• new SapphireClient<Ready>(options)

Type parameters

Name	Type
`Ready`	extends `boolean` = `boolean`

Parameters

Name	Type
`options`	`ClientOptions`

Overrides

Client<Ready\>.constructor

Defined in

projects/framework/src/lib/SapphireClient.ts:220

Properties

application

• application: If<Ready, ClientApplication, null>

Inherited from

Client.application

Defined in

node_modules/discord.js/typings/index.d.ts:472

channels

• channels: ChannelManager

Inherited from

Client.channels

Defined in

node_modules/discord.js/typings/index.d.ts:473

emojis

• Readonly emojis: BaseGuildEmojiManager

Inherited from

Client.emojis

Defined in

node_modules/discord.js/typings/index.d.ts:474

fetchPrefix

• fetchPrefix: SapphirePrefixHook

The method to be overriden by the developer.

since 1.0.0

returns A string for a single prefix, an array of strings for matching multiple, or null for no match (mention prefix only).

example

// Return always the same prefix (unconfigurable):
client.fetchPrefix = () => '!';

example

// Retrieving the prefix from a SQL database:
client.fetchPrefix = async (message) => {
  // note: driver is something generic and depends on how you connect to your database
  const guild = await driver.getOne('SELECT prefix FROM public.guild WHERE id = $1', [message.guild.id]);
  return guild?.prefix ?? '!';
};

example

// Retrieving the prefix from an ORM:
client.fetchPrefix = async (message) => {
  // note: driver is something generic and depends on how you connect to your database
  const guild = await driver.getRepository(GuildEntity).findOne({ id: message.guild.id });
  return guild?.prefix ?? '!';
};

Overrides

Client.fetchPrefix

Defined in

projects/framework/src/lib/SapphireClient.ts:205

guilds

• guilds: GuildManager

Inherited from

Client.guilds

Defined in

node_modules/discord.js/typings/index.d.ts:475

id

• id: null | string = null

The client's ID, used for the user prefix.

since 1.0.0

Overrides

Client.id

Defined in

projects/framework/src/lib/SapphireClient.ts:175

logger

• logger: ILogger

The logger to be used by the framework and plugins. By default, a Logger instance is used, which emits the messages to the console.

since 1.0.0

Overrides

Client.logger

Defined in

projects/framework/src/lib/SapphireClient.ts:212

options

• options: ClientOptions

Inherited from

Client.options

Defined in

node_modules/discord.js/typings/index.d.ts:476

readyAt

• readyAt: If<Ready, Date, null>

Inherited from

Client.readyAt

Defined in

node_modules/discord.js/typings/index.d.ts:477

readyTimestamp

• Readonly readyTimestamp: If<Ready, number, null>

Inherited from

Client.readyTimestamp

Defined in

node_modules/discord.js/typings/index.d.ts:478

shard

• shard: null | ShardClientUtil

Inherited from

Client.shard

Defined in

node_modules/discord.js/typings/index.d.ts:479

stores

• stores: StoreRegistry

The registered stores.

since 1.0.0

Overrides

Client.stores

Defined in

projects/framework/src/lib/SapphireClient.ts:218

token

• token: If<Ready, string, null | string>

Inherited from

Client.token

Defined in

node_modules/discord.js/typings/index.d.ts:480

uptime

• uptime: If<Ready, number, null>

Inherited from

Client.uptime

Defined in

node_modules/discord.js/typings/index.d.ts:481

user

• user: If<Ready, ClientUser, null>

Inherited from

Client.user

Defined in

node_modules/discord.js/typings/index.d.ts:482

users

• users: UserManager

Inherited from

Client.users

Defined in

node_modules/discord.js/typings/index.d.ts:483

voice

• voice: ClientVoiceManager

Inherited from

Client.voice

Defined in

node_modules/discord.js/typings/index.d.ts:484

ws

• ws: WebSocketManager

Inherited from

Client.ws

Defined in

node_modules/discord.js/typings/index.d.ts:485

captureRejectionSymbol

▪ Static Readonly captureRejectionSymbol: typeof captureRejectionSymbol

Inherited from

Client.captureRejectionSymbol

Defined in

node_modules/@types/node/events.d.ts:273

captureRejections

▪ Static captureRejections: boolean

Sets or gets the default captureRejection value for all emitters.

Inherited from

Client.captureRejections

Defined in

node_modules/@types/node/events.d.ts:278

defaultMaxListeners

▪ Static defaultMaxListeners: number

Inherited from

Client.defaultMaxListeners

Defined in

node_modules/@types/node/events.d.ts:279

errorMonitor

▪ Static Readonly errorMonitor: typeof errorMonitor

This symbol shall be used to install a listener for only monitoring 'error' events. Listeners installed using this symbol are called before the regular 'error' listeners are called.

Installing a listener using this symbol does not change the behavior once an 'error' event is emitted, therefore the process will still crash if no regular 'error' listener is installed.

Inherited from

Client.errorMonitor

Defined in

node_modules/@types/node/events.d.ts:272

plugins

▪ Static plugins: PluginManager

Defined in

projects/framework/src/lib/SapphireClient.ts:291

Methods

addListener

▸ addListener(eventName, listener): SapphireClient<Ready>

Alias for emitter.on(eventName, listener).

since v0.1.26

Parameters

Name	Type
`eventName`	`string` \| `symbol`
`listener`	(...`args`: `any`[]) => `void`

Returns

SapphireClient<Ready>

Inherited from

Client.addListener

Defined in

node_modules/@types/node/events.d.ts:299

destroy

▸ destroy(): void

Returns

void

Inherited from

Client.destroy

Defined in

node_modules/discord.js/typings/index.d.ts:486

emit

▸ emit<K>(event, ...args): boolean

Type parameters

Name	Type
`K`	extends keyof `ClientEvents`

Parameters

Name	Type
`event`	`K`
`...args`	`ClientEvents`[`K`]

Returns

boolean

Inherited from

Client.emit

Defined in

node_modules/discord.js/typings/index.d.ts:513

▸ emit<S>(event, ...args): boolean

Type parameters

Name	Type
`S`	extends `string` \| `symbol`

Parameters

Name	Type
`event`	`Exclude`<`S`, keyof `ClientEvents`>
`...args`	`unknown`[]

Returns

boolean

Inherited from

Client.emit

Defined in

node_modules/discord.js/typings/index.d.ts:514

eventNames

▸ eventNames(): (string | symbol)[]

Returns an array listing the events for which the emitter has registered listeners. The values in the array are strings or Symbols.

const EventEmitter = require('events');
const myEE = new EventEmitter();
myEE.on('foo', () => {});
myEE.on('bar', () => {});

const sym = Symbol('symbol');
myEE.on(sym, () => {});

console.log(myEE.eventNames());
// Prints: [ 'foo', 'bar', Symbol(symbol) ]

since v6.0.0

Returns

(string | symbol)[]

Inherited from

Client.eventNames

Defined in

node_modules/@types/node/events.d.ts:614

fetchGuildPreview

▸ fetchGuildPreview(guild): Promise<GuildPreview>

Parameters

Name	Type
`guild`	`GuildResolvable`

Returns

Promise<GuildPreview>

Inherited from

Client.fetchGuildPreview

Defined in

node_modules/discord.js/typings/index.d.ts:487

fetchGuildTemplate

▸ fetchGuildTemplate(template): Promise<GuildTemplate>

Parameters

Name	Type
`template`	`string`

Returns

Promise<GuildTemplate>

Inherited from

Client.fetchGuildTemplate

Defined in

node_modules/discord.js/typings/index.d.ts:489

fetchGuildWidget

▸ fetchGuildWidget(guild): Promise<Widget>

Parameters

Name	Type
`guild`	`GuildResolvable`

Returns

Promise<Widget>

Inherited from

Client.fetchGuildWidget

Defined in

node_modules/discord.js/typings/index.d.ts:494

fetchInvite

▸ fetchInvite(invite): Promise<Invite>

Parameters

Name	Type
`invite`	`string`

Returns

Promise<Invite>

Inherited from

Client.fetchInvite

Defined in

node_modules/discord.js/typings/index.d.ts:488

fetchPremiumStickerPacks

▸ fetchPremiumStickerPacks(): Promise<Collection<string, StickerPack>>

Returns

Promise<Collection<string, StickerPack>>

Inherited from

Client.fetchPremiumStickerPacks

Defined in

node_modules/discord.js/typings/index.d.ts:492

fetchSticker

▸ fetchSticker(id): Promise<Sticker>

Parameters

Name	Type
`id`	`string`

Returns

Promise<Sticker>

Inherited from

Client.fetchSticker

Defined in

node_modules/discord.js/typings/index.d.ts:491

fetchVoiceRegions

▸ fetchVoiceRegions(): Promise<Collection<string, VoiceRegion>>

Returns

Promise<Collection<string, VoiceRegion>>

Inherited from

Client.fetchVoiceRegions

Defined in

node_modules/discord.js/typings/index.d.ts:490

fetchWebhook

▸ fetchWebhook(id, token?): Promise<Webhook>

Parameters

Name	Type
`id`	`string`
`token?`	`string`

Returns

Promise<Webhook>

Inherited from

Client.fetchWebhook

Defined in

node_modules/discord.js/typings/index.d.ts:493

generateInvite

▸ generateInvite(options?): string

Parameters

Name	Type
`options?`	`InviteGenerationOptions`

Returns

string

Inherited from

Client.generateInvite

Defined in

node_modules/discord.js/typings/index.d.ts:495

getMaxListeners

▸ getMaxListeners(): number

Returns the current max listener value for the EventEmitter which is either set by emitter.setMaxListeners(n) or defaults to defaultMaxListeners.

since v1.0.0

Returns

number

Inherited from

Client.getMaxListeners

Defined in

node_modules/@types/node/events.d.ts:471

isReady

▸ isReady(): this is Client<true>

Returns

this is Client<true>

Inherited from

Client.isReady

Defined in

node_modules/discord.js/typings/index.d.ts:497

listenerCount

▸ listenerCount(eventName): number

Returns the number of listeners listening to the event named eventName.

since v3.2.0

Parameters

Name	Type	Description
`eventName`	`string` \| `symbol`	The name of the event being listened for

Returns

number

Inherited from

Client.listenerCount

Defined in

node_modules/@types/node/events.d.ts:561

listeners

▸ listeners(eventName): Function[]

Returns a copy of the array of listeners for the event named eventName.

server.on('connection', (stream) => {
  console.log('someone connected!');
});
console.log(util.inspect(server.listeners('connection')));
// Prints: [ [Function] ]

since v0.1.26

Parameters

Name	Type
`eventName`	`string` \| `symbol`

Returns

Function[]

Inherited from

Client.listeners

Defined in

node_modules/@types/node/events.d.ts:484

▸ login(token?): Promise<string>

Loads all pieces, then logs the client in, establishing a websocket connection to Discord.

since 1.0.0

Parameters

Name	Type	Description
`token?`	`string`	Token of the account to log in with.

Returns

Promise<string>

Token of the account used.

Overrides

Client.login

Defined in

projects/framework/src/lib/SapphireClient.ts:266

off

▸ off<K>(event, listener): SapphireClient<Ready>

Type parameters

Name	Type
`K`	extends keyof `ClientEvents`

Parameters

Name	Type
`event`	`K`
`listener`	(...`args`: `ClientEvents`[`K`]) => `Awaitable`<`void`>

Returns

SapphireClient<Ready>

Inherited from

Client.off

Defined in

node_modules/discord.js/typings/index.d.ts:516

▸ off<S>(event, listener): SapphireClient<Ready>

Type parameters

Name	Type
`S`	extends `string` \| `symbol`

Parameters

Name	Type
`event`	`Exclude`<`S`, keyof `ClientEvents`>
`listener`	(...`args`: `any`[]) => `Awaitable`<`void`>

Returns

SapphireClient<Ready>

Inherited from

Client.off

Defined in

node_modules/discord.js/typings/index.d.ts:517

on

▸ on<K>(event, listener): SapphireClient<Ready>

Type parameters

Name	Type
`K`	extends keyof `ClientEvents`

Parameters

Name	Type
`event`	`K`
`listener`	(...`args`: `ClientEvents`[`K`]) => `Awaitable`<`void`>

Returns

SapphireClient<Ready>

Inherited from

Client.on

Defined in

node_modules/discord.js/typings/index.d.ts:501

▸ on<S>(event, listener): SapphireClient<Ready>

Type parameters

Name	Type
`S`	extends `string` \| `symbol`

Parameters

Name	Type
`event`	`Exclude`<`S`, keyof `ClientEvents`>
`listener`	(...`args`: `any`[]) => `Awaitable`<`void`>

Returns

SapphireClient<Ready>

Inherited from

Client.on

Defined in

node_modules/discord.js/typings/index.d.ts:502

once

▸ once<K>(event, listener): SapphireClient<Ready>

Type parameters

Name	Type
`K`	extends keyof `ClientEvents`

Parameters

Name	Type
`event`	`K`
`listener`	(...`args`: `ClientEvents`[`K`]) => `Awaitable`<`void`>

Returns

SapphireClient<Ready>

Inherited from

Client.once

Defined in

node_modules/discord.js/typings/index.d.ts:507

▸ once<S>(event, listener): SapphireClient<Ready>

Type parameters

Name	Type
`S`	extends `string` \| `symbol`

Parameters

Name	Type
`event`	`Exclude`<`S`, keyof `ClientEvents`>
`listener`	(...`args`: `any`[]) => `Awaitable`<`void`>

Returns

SapphireClient<Ready>

Inherited from

Client.once

Defined in

node_modules/discord.js/typings/index.d.ts:508

prependListener

▸ prependListener(eventName, listener): SapphireClient<Ready>

Adds the listener function to the beginning of the listeners array for the event named eventName. No checks are made to see if the listener has already been added. Multiple calls passing the same combination of eventNameand listener will result in the listener being added, and called, multiple times.

server.prependListener('connection', (stream) => {
  console.log('someone connected!');
});

Returns a reference to the EventEmitter, so that calls can be chained.

since v6.0.0

Parameters

Name	Type	Description
`eventName`	`string` \| `symbol`	The name of the event.
`listener`	(...`args`: `any`[]) => `void`	The callback function

Returns

SapphireClient<Ready>

Inherited from

Client.prependListener

Defined in

node_modules/@types/node/events.d.ts:579

prependOnceListener

▸ prependOnceListener(eventName, listener): SapphireClient<Ready>

Adds a one-timelistener function for the event named eventName to thebeginning of the listeners array. The next time eventName is triggered, this listener is removed, and then invoked.

server.prependOnceListener('connection', (stream) => {
  console.log('Ah, we have our first user!');
});

Returns a reference to the EventEmitter, so that calls can be chained.

since v6.0.0

Parameters

Name	Type	Description
`eventName`	`string` \| `symbol`	The name of the event.
`listener`	(...`args`: `any`[]) => `void`	The callback function

Returns

SapphireClient<Ready>

Inherited from

Client.prependOnceListener

Defined in

node_modules/@types/node/events.d.ts:595

rawListeners

▸ rawListeners(eventName): Function[]

Returns a copy of the array of listeners for the event named eventName, including any wrappers (such as those created by .once()).

const emitter = new EventEmitter();
emitter.once('log', () => console.log('log once'));

// Returns a new Array with a function `onceWrapper` which has a property
// `listener` which contains the original listener bound above
const listeners = emitter.rawListeners('log');
const logFnWrapper = listeners[0];

// Logs "log once" to the console and does not unbind the `once` event
logFnWrapper.listener();

// Logs "log once" to the console and removes the listener
logFnWrapper();

emitter.on('log', () => console.log('log persistently'));
// Will return a new Array with a single function bound by `.on()` above
const newListeners = emitter.rawListeners('log');

// Logs "log persistently" twice
newListeners[0]();
emitter.emit('log');

since v9.4.0

Parameters

Name	Type
`eventName`	`string` \| `symbol`

Returns

Function[]

Inherited from

Client.rawListeners

Defined in

node_modules/@types/node/events.d.ts:514

removeAllListeners

▸ removeAllListeners<K>(event?): SapphireClient<Ready>

Type parameters

Name	Type
`K`	extends keyof `ClientEvents`

Parameters

Name	Type
`event?`	`K`

Returns

SapphireClient<Ready>

Inherited from

Client.removeAllListeners

Defined in

node_modules/discord.js/typings/index.d.ts:522

▸ removeAllListeners<S>(event?): SapphireClient<Ready>

Type parameters

Name	Type
`S`	extends `string` \| `symbol`

Parameters

Name	Type
`event?`	`Exclude`<`S`, keyof `ClientEvents`>

Returns

SapphireClient<Ready>

Inherited from

Client.removeAllListeners

Defined in

node_modules/discord.js/typings/index.d.ts:523

removeListener

▸ removeListener(eventName, listener): SapphireClient<Ready>

Removes the specified listener from the listener array for the event namedeventName.

const callback = (stream) => {
  console.log('someone connected!');
};
server.on('connection', callback);
// ...
server.removeListener('connection', callback);

removeListener() will remove, at most, one instance of a listener from the listener array. If any single listener has been added multiple times to the listener array for the specified eventName, then removeListener() must be called multiple times to remove each instance.

Once an event is emitted, all listeners attached to it at the time of emitting are called in order. This implies that anyremoveListener() or removeAllListeners() calls after emitting andbefore the last listener finishes execution will not remove them fromemit() in progress. Subsequent events behave as expected.

const myEmitter = new MyEmitter();

const callbackA = () => {
  console.log('A');
  myEmitter.removeListener('event', callbackB);
};

const callbackB = () => {
  console.log('B');
};

myEmitter.on('event', callbackA);

myEmitter.on('event', callbackB);

// callbackA removes listener callbackB but it will still be called.
// Internal listener array at time of emit [callbackA, callbackB]
myEmitter.emit('event');
// Prints:
//   A
//   B

// callbackB is now removed.
// Internal listener array [callbackA]
myEmitter.emit('event');
// Prints:
//   A

Because listeners are managed using an internal array, calling this will change the position indices of any listener registered after the listener being removed. This will not impact the order in which listeners are called, but it means that any copies of the listener array as returned by the emitter.listeners() method will need to be recreated.

When a single function has been added as a handler multiple times for a single event (as in the example below), removeListener() will remove the most recently added instance. In the example the once('ping')listener is removed:

const ee = new EventEmitter();

function pong() {
  console.log('pong');
}

ee.on('ping', pong);
ee.once('ping', pong);
ee.removeListener('ping', pong);

ee.emit('ping');
ee.emit('ping');

Returns a reference to the EventEmitter, so that calls can be chained.

since v0.1.26

Parameters

Name	Type
`eventName`	`string` \| `symbol`
`listener`	(...`args`: `any`[]) => `void`

Returns

SapphireClient<Ready>

Inherited from

Client.removeListener

Defined in

node_modules/@types/node/events.d.ts:439

setMaxListeners

▸ setMaxListeners(n): SapphireClient<Ready>

By default EventEmitters will print a warning if more than 10 listeners are added for a particular event. This is a useful default that helps finding memory leaks. The emitter.setMaxListeners() method allows the limit to be modified for this specific EventEmitter instance. The value can be set toInfinity (or 0) to indicate an unlimited number of listeners.

Returns a reference to the EventEmitter, so that calls can be chained.

since v0.3.5

Parameters

Name	Type
`n`	`number`

Returns

SapphireClient<Ready>

Inherited from

Client.setMaxListeners

Defined in

node_modules/@types/node/events.d.ts:465

sweepMessages

▸ sweepMessages(lifetime?): number

Parameters

Name	Type
`lifetime?`	`number`

Returns

number

Inherited from

Client.sweepMessages

Defined in

node_modules/discord.js/typings/index.d.ts:498

toJSON

▸ toJSON(): unknown

Returns

unknown

Inherited from

Client.toJSON

Defined in

node_modules/discord.js/typings/index.d.ts:499

getEventListeners

▸ Static getEventListeners(emitter, name): Function[]

Returns a copy of the array of listeners for the event named eventName.

For EventEmitters this behaves exactly the same as calling .listeners on the emitter.

For EventTargets this is the only way to get the event listeners for the event target. This is useful for debugging and diagnostic purposes.

const { getEventListeners, EventEmitter } = require('events');

{
  const ee = new EventEmitter();
  const listener = () => console.log('Events are fun');
  ee.on('foo', listener);
  getEventListeners(ee, 'foo'); // [listener]
}
{
  const et = new EventTarget();
  const listener = () => console.log('Events are fun');
  et.addEventListener('foo', listener);
  getEventListeners(et, 'foo'); // [listener]
}

since v15.2.0

Parameters

Name	Type
`emitter`	`EventEmitter` \| `DOMEventTarget`
`name`	`string` \| `symbol`

Returns

Function[]

Inherited from

Client.getEventListeners

Defined in

node_modules/@types/node/events.d.ts:262

listenerCount

▸ Static listenerCount(emitter, eventName): number

A class method that returns the number of listeners for the given eventNameregistered on the given emitter.

const { EventEmitter, listenerCount } = require('events');
const myEmitter = new EventEmitter();
myEmitter.on('event', () => {});
myEmitter.on('event', () => {});
console.log(listenerCount(myEmitter, 'event'));
// Prints: 2

since v0.9.12

deprecated Since v3.2.0 - Use listenerCount instead.

Parameters

Name	Type	Description
`emitter`	`EventEmitter`	The emitter to query
`eventName`	`string` \| `symbol`	The event name

Returns

number

Inherited from

Client.listenerCount

Defined in

node_modules/@types/node/events.d.ts:234

on

▸ Static on(emitter, eventName, options?): AsyncIterableIterator<any>

const { on, EventEmitter } = require('events');

(async () => {
  const ee = new EventEmitter();

  // Emit later on
  process.nextTick(() => {
    ee.emit('foo', 'bar');
    ee.emit('foo', 42);
  });

  for await (const event of on(ee, 'foo')) {
    // The execution of this inner block is synchronous and it
    // processes one event at a time (even with await). Do not use
    // if concurrent execution is required.
    console.log(event); // prints ['bar'] [42]
  }
  // Unreachable here
})();

Returns an AsyncIterator that iterates eventName events. It will throw if the EventEmitter emits 'error'. It removes all listeners when exiting the loop. The value returned by each iteration is an array composed of the emitted event arguments.

An AbortSignal can be used to cancel waiting on events:

const { on, EventEmitter } = require('events');
const ac = new AbortController();

(async () => {
  const ee = new EventEmitter();

  // Emit later on
  process.nextTick(() => {
    ee.emit('foo', 'bar');
    ee.emit('foo', 42);
  });

  for await (const event of on(ee, 'foo', { signal: ac.signal })) {
    // The execution of this inner block is synchronous and it
    // processes one event at a time (even with await). Do not use
    // if concurrent execution is required.
    console.log(event); // prints ['bar'] [42]
  }
  // Unreachable here
})();

process.nextTick(() => ac.abort());

since v13.6.0, v12.16.0

Parameters

Name	Type	Description
`emitter`	`EventEmitter`	-
`eventName`	`string`	The name of the event being listened for
`options?`	`StaticEventEmitterOptions`	-

Returns

AsyncIterableIterator<any>

that iterates eventName events emitted by the emitter

Inherited from

Client.on

Defined in

node_modules/@types/node/events.d.ts:217

once

▸ Static once(emitter, eventName, options?): Promise<any[]>

Creates a Promise that is fulfilled when the EventEmitter emits the given event or that is rejected if the EventEmitter emits 'error' while waiting. The Promise will resolve with an array of all the arguments emitted to the given event.

This method is intentionally generic and works with the web platform EventTarget interface, which has no special'error' event semantics and does not listen to the 'error' event.

const { once, EventEmitter } = require('events');

async function run() {
  const ee = new EventEmitter();

  process.nextTick(() => {
    ee.emit('myevent', 42);
  });

  const [value] = await once(ee, 'myevent');
  console.log(value);

  const err = new Error('kaboom');
  process.nextTick(() => {
    ee.emit('error', err);
  });

  try {
    await once(ee, 'myevent');
  } catch (err) {
    console.log('error happened', err);
  }
}

run();

The special handling of the 'error' event is only used when events.once()is used to wait for another event. If events.once() is used to wait for the 'error' event itself, then it is treated as any other kind of event without special handling:

const { EventEmitter, once } = require('events');

const ee = new EventEmitter();

once(ee, 'error')
  .then(([err]) => console.log('ok', err.message))
  .catch((err) => console.log('error', err.message));

ee.emit('error', new Error('boom'));

// Prints: ok boom

An AbortSignal can be used to cancel waiting for the event:

const { EventEmitter, once } = require('events');

const ee = new EventEmitter();
const ac = new AbortController();

async function foo(emitter, event, signal) {
  try {
    await once(emitter, event, { signal });
    console.log('event emitted!');
  } catch (error) {
    if (error.name === 'AbortError') {
      console.error('Waiting for the event was canceled!');
    } else {
      console.error('There was an error', error.message);
    }
  }
}

foo(ee, 'foo', ac.signal);
ac.abort(); // Abort waiting for the event
ee.emit('foo'); // Prints: Waiting for the event was canceled!

since v11.13.0, v10.16.0

Parameters

Name	Type
`emitter`	`NodeEventTarget`
`eventName`	`string` \| `symbol`
`options?`	`StaticEventEmitterOptions`

Returns

Promise<any[]>

Inherited from

Client.once

Defined in

node_modules/@types/node/events.d.ts:157

▸ Static once(emitter, eventName, options?): Promise<any[]>

Parameters

Name	Type
`emitter`	`DOMEventTarget`
`eventName`	`string`
`options?`	`StaticEventEmitterOptions`

Returns

Promise<any[]>

Inherited from

Client.once

Defined in

node_modules/@types/node/events.d.ts:158

use

▸ Static use(plugin): typeof SapphireClient

Parameters

Name	Type
`plugin`	typeof `Plugin`

Returns

typeof SapphireClient

Defined in

projects/framework/src/lib/SapphireClient.ts:293

Type parameters​

Hierarchy​

Constructors​

constructor​

Type parameters​

Parameters​

Overrides​

Defined in​

Properties​

application​

Inherited from​

Defined in​

channels​

Inherited from​

Defined in​

emojis​

Inherited from​

Defined in​

fetchPrefix​

Overrides​

Defined in​

guilds​

Inherited from​

Defined in​

id​

Overrides​

Defined in​

logger​

Overrides​

Defined in​

options​

Inherited from​

Defined in​

readyAt​

Inherited from​

Defined in​

readyTimestamp​

Inherited from​

Defined in​

shard​

Inherited from​

Defined in​

stores​

Overrides​

Defined in​

token​

Inherited from​

Defined in​

uptime​

Inherited from​

Defined in​

user​

Inherited from​

Defined in​

users​

Inherited from​

Defined in​

voice​

Inherited from​

Defined in​

ws​

Inherited from​

Defined in​

captureRejectionSymbol​

Inherited from​

Defined in​

captureRejections​

Inherited from​

Defined in​

defaultMaxListeners​

Inherited from​

Defined in​

errorMonitor​

Inherited from​

Defined in​

plugins​

Defined in​

Methods​

addListener​

Parameters​

Type parameters

Hierarchy

Constructors

constructor

Type parameters

Parameters

Overrides

Defined in

Properties

application

Inherited from

Defined in

channels

Inherited from

Defined in

emojis

Inherited from

Defined in

fetchPrefix

Overrides

Defined in

guilds

Inherited from

Defined in

id

Overrides

Defined in

logger

Overrides

Defined in

options

Inherited from

Defined in

readyAt

Inherited from

Defined in

readyTimestamp

Inherited from

Defined in

shard

Inherited from

Defined in

stores

Overrides

Defined in

token

Inherited from

Defined in

uptime

Inherited from

Defined in

user

Inherited from

Defined in

users

Inherited from

Defined in

voice

Inherited from

Defined in

ws

Inherited from

Defined in

captureRejectionSymbol

Inherited from

Defined in

captureRejections

Inherited from

Defined in

defaultMaxListeners

Inherited from

Defined in

errorMonitor

Inherited from

Defined in

plugins

Defined in

Methods

addListener

Parameters