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:262
Properties
application
• application: If
<Ready
, ClientApplication
, null
>
Inherited from
Client.application
Defined in
node_modules/discord.js/typings/index.d.ts:584
channels
• channels: ChannelManager
Inherited from
Client.channels
Defined in
node_modules/discord.js/typings/index.d.ts:585
disableMentionPrefix
• Optional
disableMentionPrefix: boolean
Whether the bot has mention as a prefix disabled
default
false
example
client.disableMentionPrefix = false;
Defined in
projects/framework/src/lib/SapphireClient.ts:254
emojis
• Readonly
emojis: BaseGuildEmojiManager
Inherited from
Client.emojis
Defined in
node_modules/discord.js/typings/index.d.ts:586
fetchPrefix
• fetchPrefix: SapphirePrefixHook
The method to be overridden 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:237
guilds
• guilds: GuildManager
Inherited from
Client.guilds
Defined in
node_modules/discord.js/typings/index.d.ts:587
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:207
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:244
options
• options: ClientOptions
Inherited from
Client.options
Defined in
node_modules/discord.js/typings/index.d.ts:588
readyAt
• readyAt: If
<Ready
, Date
, null
>
Inherited from
Client.readyAt
Defined in
node_modules/discord.js/typings/index.d.ts:589
readyTimestamp
• Readonly
readyTimestamp: If
<Ready
, number
, null
>
Inherited from
Client.readyTimestamp
Defined in
node_modules/discord.js/typings/index.d.ts:590
shard
• shard: null
| ShardClientUtil
Inherited from
Client.shard
Defined in
node_modules/discord.js/typings/index.d.ts:592
stores
• stores: StoreRegistry
The registered stores.
since
1.0.0
Overrides
Client.stores
Defined in
projects/framework/src/lib/SapphireClient.ts:260
sweepers
• sweepers: Sweepers
Inherited from
Client.sweepers
Defined in
node_modules/discord.js/typings/index.d.ts:591
token
• token: If
<Ready
, string
, null
| string
>
Inherited from
Client.token
Defined in
node_modules/discord.js/typings/index.d.ts:593
uptime
• uptime: If
<Ready
, number
, null
>
Inherited from
Client.uptime
Defined in
node_modules/discord.js/typings/index.d.ts:594
user
• user: If
<Ready
, ClientUser
, null
>
Inherited from
Client.user
Defined in
node_modules/discord.js/typings/index.d.ts:595
users
• users: UserManager
Inherited from
Client.users
Defined in
node_modules/discord.js/typings/index.d.ts:596
voice
• voice: ClientVoiceManager
Inherited from
Client.voice
Defined in
node_modules/discord.js/typings/index.d.ts:597
ws
• ws: WebSocketManager
Inherited from
Client.ws
Defined in
node_modules/discord.js/typings/index.d.ts:598
captureRejectionSymbol
▪ Static
Readonly
captureRejectionSymbol: typeof captureRejectionSymbol
Inherited from
Client.captureRejectionSymbol
Defined in
node_modules/@types/node/events.d.ts:301
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:306
defaultMaxListeners
▪ Static
defaultMaxListeners: number
Inherited from
Client.defaultMaxListeners
Defined in
node_modules/@types/node/events.d.ts:307
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:300
plugins
▪ Static
plugins: PluginManager
Defined in
projects/framework/src/lib/SapphireClient.ts:345
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:327
destroy
▸ destroy(): void
Returns
void
Inherited from
Client.destroy
Defined in
node_modules/discord.js/typings/index.d.ts:599
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:627
▸ 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:628
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 Symbol
s.
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:642
fetchGuildPreview
▸ fetchGuildPreview(guild
): Promise
<GuildPreview
>
Parameters
Name | Type |
---|---|
guild | GuildResolvable |
Returns
Inherited from
Client.fetchGuildPreview
Defined in
node_modules/discord.js/typings/index.d.ts:600
fetchGuildTemplate
▸ fetchGuildTemplate(template
): Promise
<GuildTemplate
>
Parameters
Name | Type |
---|---|
template | string |
Returns
Inherited from
Client.fetchGuildTemplate
Defined in
node_modules/discord.js/typings/index.d.ts:602
fetchGuildWidget
▸ fetchGuildWidget(guild
): Promise
<Widget
>
Parameters
Name | Type |
---|---|
guild | GuildResolvable |
Returns
Inherited from
Client.fetchGuildWidget
Defined in
node_modules/discord.js/typings/index.d.ts:607
fetchInvite
▸ fetchInvite(invite
, options?
): Promise
<Invite
>
Parameters
Name | Type |
---|---|
invite | string |
options? | ClientFetchInviteOptions |
Returns
Inherited from
Client.fetchInvite
Defined in
node_modules/discord.js/typings/index.d.ts:601
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:605
fetchSticker
▸ fetchSticker(id
): Promise
<Sticker
>
Parameters
Name | Type |
---|---|
id | string |
Returns
Inherited from
Client.fetchSticker
Defined in
node_modules/discord.js/typings/index.d.ts:604
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:603
fetchWebhook
▸ fetchWebhook(id
, token?
): Promise
<Webhook
>
Parameters
Name | Type |
---|---|
id | string |
token? | string |
Returns
Inherited from
Client.fetchWebhook
Defined in
node_modules/discord.js/typings/index.d.ts:606
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:608
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:499
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:610
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:589
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:512
login
▸ 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:320
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:630
▸ 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:631
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:615
▸ 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:616
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:621
▸ 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:622
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 eventName
and 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:607
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:623
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:542
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:636
▸ 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:637
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:467
setMaxListeners
▸ setMaxListeners(n
): SapphireClient
<Ready
>
By default EventEmitter
s 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:493
sweepMessages
▸ sweepMessages(lifetime?
): number
deprecated
Use {@link Sweepers#sweepMessages} instead
Parameters
Name | Type |
---|---|
lifetime? | number |
Returns
number
Inherited from
Client.sweepMessages
Defined in
node_modules/discord.js/typings/index.d.ts:612
toJSON
▸ toJSON(): unknown
Returns
unknown
Inherited from
Client.toJSON
Defined in
node_modules/discord.js/typings/index.d.ts:613
getEventListeners
▸ Static
getEventListeners(emitter
, name
): Function
[]
Returns a copy of the array of listeners for the event named eventName
.
For EventEmitter
s this behaves exactly the same as calling .listeners
on
the emitter.
For EventTarget
s 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, v14.17.0
Parameters
Name | Type |
---|---|
emitter | EventEmitter | DOMEventTarget |
name | string | symbol |
Returns
Function
[]
Inherited from
Client.getEventListeners
Defined in
node_modules/@types/node/events.d.ts:270
listenerCount
▸ Static
listenerCount(emitter
, eventName
): number
A class method that returns the number of listeners for the given eventName
registered 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:242
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:221
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:162
setMaxListeners
▸ Static
setMaxListeners(n?
, ...eventTargets
): void
By default EventEmitter
s 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 EventEmitter.setMaxListeners()
method allows the default limit to be
modified (if eventTargets is empty) or modify the limit specified in every EventTarget
| EventEmitter
passed as arguments.
The value can be set toInfinity
(or 0
) to indicate an unlimited number of listeners.
EventEmitter.setMaxListeners(20);
// Equivalent to
EventEmitter.defaultMaxListeners = 20;
const eventTarget = new EventTarget();
// Only way to increase limit for `EventTarget` instances
// as these doesn't expose its own `setMaxListeners` method
EventEmitter.setMaxListeners(20, eventTarget);
since
v15.3.0, v14.17.0
Parameters
Name | Type |
---|---|
n? | number |
...eventTargets | (EventEmitter | DOMEventTarget )[] |
Returns
void
Inherited from
Client.setMaxListeners
Defined in
node_modules/@types/node/events.d.ts:290
use
▸ Static
use(plugin
): typeof SapphireClient
Parameters
Name | Type |
---|---|
plugin | typeof Plugin |
Returns
typeof SapphireClient