Class: SapphireClient<Ready>
The base 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
): SapphireClient
<Ready
>
Type parameters
Name | Type |
---|---|
Ready | extends boolean = boolean |
Parameters
Name | Type |
---|---|
options | ClientOptions |
Returns
SapphireClient
<Ready
>
Overrides
Client<Ready>.constructor
Defined in
projects/framework/src/lib/SapphireClient.ts:279
Properties
application
• application: If
<Ready
, ClientApplication
, null
>
Inherited from
Client.application
Defined in
node_modules/discord.js/typings/index.d.ts:971
channels
• channels: ChannelManager
Inherited from
Client.channels
Defined in
node_modules/discord.js/typings/index.d.ts:972
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:271
fetchPrefix
• fetchPrefix: SapphirePrefixHook
The method to be overridden by the developer.
Since
1.0.0
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:254
guilds
• guilds: GuildManager
Inherited from
Client.guilds
Defined in
node_modules/discord.js/typings/index.d.ts:974
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:224
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:261
options
• options: Omit
<ClientOptions
, "intents"
> & { intents
: IntentsBitField
}
Inherited from
Client.options
Defined in
node_modules/discord.js/typings/index.d.ts:975
readyTimestamp
• readyTimestamp: If
<Ready
, number
, null
>
Inherited from
Client.readyTimestamp
Defined in
node_modules/discord.js/typings/index.d.ts:977
rest
• rest: REST
Inherited from
Client.rest
Defined in
node_modules/discord.js/typings/index.d.ts:521
shard
• shard: null
| ShardClientUtil
Inherited from
Client.shard
Defined in
node_modules/discord.js/typings/index.d.ts:979
stores
• stores: StoreRegistry
The registered stores.
Since
1.0.0
Overrides
Client.stores
Defined in
projects/framework/src/lib/SapphireClient.ts:277
sweepers
• sweepers: Sweepers
Inherited from
Client.sweepers
Defined in
node_modules/discord.js/typings/index.d.ts:978
token
• token: If
<Ready
, string
, null
| string
>
Inherited from
Client.token
Defined in
node_modules/discord.js/typings/index.d.ts:980
user
• user: If
<Ready
, ClientUser
, null
>
Inherited from
Client.user
Defined in
node_modules/discord.js/typings/index.d.ts:982
users
• users: UserManager
Inherited from
Client.users
Defined in
node_modules/discord.js/typings/index.d.ts:983
voice
• voice: ClientVoiceManager
Inherited from
Client.voice
Defined in
node_modules/discord.js/typings/index.d.ts:984
ws
• ws: WebSocketManager
Inherited from
Client.ws
Defined in
node_modules/discord.js/typings/index.d.ts:985
captureRejectionSymbol
▪ Static
Readonly
captureRejectionSymbol: typeof captureRejectionSymbol
Value: Symbol.for('nodejs.rejection')
See how to write a custom rejection handler
.
Since
v13.4.0, v12.16.0
Inherited from
Client.captureRejectionSymbol
Defined in
node_modules/@types/node/events.d.ts:419
captureRejections
▪ Static
captureRejections: boolean
Value: boolean
Change the default captureRejections
option on all new EventEmitter
objects.
Since
v13.4.0, v12.16.0
Inherited from
Client.captureRejections
Defined in
node_modules/@types/node/events.d.ts:426
defaultMaxListeners
▪ Static
defaultMaxListeners: number
By default, a maximum of 10
listeners can be registered for any single
event. This limit can be changed for individual EventEmitter
instances
using the emitter.setMaxListeners(n)
method. To change the default
for allEventEmitter
instances, the events.defaultMaxListeners
property can be used. If this value is not a positive number, a RangeError
is thrown.
Take caution when setting the events.defaultMaxListeners
because the
change affects allEventEmitter
instances, including those created before
the change is made. However, calling emitter.setMaxListeners(n)
still has
precedence over events.defaultMaxListeners
.
This is not a hard limit. The EventEmitter
instance will allow
more listeners to be added but will output a trace warning to stderr indicating
that a "possible EventEmitter memory leak" has been detected. For any singleEventEmitter
, the emitter.getMaxListeners()
and emitter.setMaxListeners()
methods can be used to
temporarily avoid this warning:
import { EventEmitter } from 'node:events';
const emitter = new EventEmitter();
emitter.setMaxListeners(emitter.getMaxListeners() + 1);
emitter.once('event', () => {
// do stuff
emitter.setMaxListeners(Math.max(emitter.getMaxListeners() - 1, 0));
});
The --trace-warnings
command-line flag can be used to display the
stack trace for such warnings.
The emitted warning can be inspected with process.on('warning')
and will
have the additional emitter
, type
, and count
properties, referring to
the event emitter instance, the event's name and the number of attached
listeners, respectively.
Its name
property is set to 'MaxListenersExceededWarning'
.
Since
v0.11.2
Inherited from
Client.defaultMaxListeners
Defined in
node_modules/@types/node/events.d.ts:463
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.
Since
v13.6.0, v12.17.0
Inherited from
Client.errorMonitor
Defined in
node_modules/@types/node/events.d.ts:412
plugins
▪ Static
plugins: PluginManager
Defined in
projects/framework/src/lib/SapphireClient.ts:363
Accessors
_censoredToken
• get
_censoredToken(): null
| string
Returns
null
| string
Inherited from
Client._censoredToken
Defined in
node_modules/discord.js/typings/index.d.ts:967
emojis
• get
emojis(): BaseGuildEmojiManager
Returns
Inherited from
Client.emojis
Defined in
node_modules/discord.js/typings/index.d.ts:973
readyAt
• get
readyAt(): If
<Ready
, Date
, null
>
Returns
Inherited from
Client.readyAt
Defined in
node_modules/discord.js/typings/index.d.ts:976
uptime
• get
uptime(): If
<Ready
, number
, null
>
Returns
If
<Ready
, number
, null
>
Inherited from
Client.uptime
Defined in
node_modules/discord.js/typings/index.d.ts:981
Methods
[captureRejectionSymbol]
▸ [captureRejectionSymbol]<K
>(error
, event
, ...args
): void
Type parameters
Name |
---|
K |
Parameters
Name | Type |
---|---|
error | Error |
event | string | symbol |
...args | AnyRest |
Returns
void
Inherited from
Client.[captureRejectionSymbol]
Defined in
node_modules/@types/node/events.d.ts:129
addListener
▸ addListener<K
>(eventName
, listener
): this
Alias for emitter.on(eventName, listener)
.
Type parameters
Name |
---|
K |
Parameters
Name | Type |
---|---|
eventName | string | symbol |
listener | (...args : any []) => void |
Returns
this
Since
v0.1.26
Inherited from
Client.addListener
Defined in
node_modules/@types/node/events.d.ts:562
deleteWebhook
▸ deleteWebhook(id
, options?
): Promise
<void
>
Parameters
Name | Type |
---|---|
id | string |
options? | WebhookDeleteOptions |
Returns
Promise
<void
>
Inherited from
Client.deleteWebhook
Defined in
node_modules/discord.js/typings/index.d.ts:987
destroy
▸ destroy(): Promise
<void
>
Returns
Promise
<void
>
Inherited from
Client.destroy
Defined in
node_modules/discord.js/typings/index.d.ts:986
emit
▸ emit<Event
>(event
, ...args
): boolean
Type parameters
Name | Type |
---|---|
Event | extends keyof ClientEvents |
Parameters
Name | Type |
---|---|
event | Event |
...args | ClientEvents [Event ] |
Returns
boolean
Inherited from
Client.emit
Defined in
node_modules/discord.js/typings/index.d.ts:1021
▸ emit<Event
>(event
, ...args
): boolean
Type parameters
Name | Type |
---|---|
Event | extends string | symbol |
Parameters
Name | Type |
---|---|
event | Exclude <Event , keyof ClientEvents > |
...args | unknown [] |
Returns
boolean
Inherited from
Client.emit
Defined in
node_modules/discord.js/typings/index.d.ts:1022
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.
import { EventEmitter } from 'node: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) ]
Returns
(string
| symbol
)[]
Since
v6.0.0
Inherited from
Client.eventNames
Defined in
node_modules/@types/node/events.d.ts:887
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:988
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:990
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:997
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:989
fetchPremiumStickerPacks
▸ fetchPremiumStickerPacks(): Promise
<Collection
<string
, StickerPack
>>
Returns
Promise
<Collection
<string
, StickerPack
>>
Deprecated
Use fetchStickerPacks instead.
Inherited from
Client.fetchPremiumStickerPacks
Defined in
node_modules/discord.js/typings/index.d.ts:995
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:992
fetchStickerPacks
▸ fetchStickerPacks(): Promise
<Collection
<string
, StickerPack
>>
Returns
Promise
<Collection
<string
, StickerPack
>>
Inherited from
Client.fetchStickerPacks
Defined in
node_modules/discord.js/typings/index.d.ts:993
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:991
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:996
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:998
getMaxListeners
▸ getMaxListeners(): number
Returns the current max listener value for the EventEmitter
which is either
set by emitter.setMaxListeners(n)
or defaults to defaultMaxListeners.
Returns
number
Since
v1.0.0
Inherited from
Client.getMaxListeners
Defined in
node_modules/@types/node/events.d.ts:739
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:1000
listenerCount
▸ listenerCount<K
>(eventName
, listener?
): number
Returns the number of listeners listening for the event named eventName
.
If listener
is provided, it will return how many times the listener is found
in the list of the listeners of the event.
Type parameters
Name |
---|
K |
Parameters
Name | Type | Description |
---|---|---|
eventName | string | symbol | The name of the event being listened for |
listener? | Function | The event handler function |
Returns
number
Since
v3.2.0
Inherited from
Client.listenerCount
Defined in
node_modules/@types/node/events.d.ts:833
listeners
▸ listeners<K
>(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] ]
Type parameters
Name |
---|
K |
Parameters
Name | Type |
---|---|
eventName | string | symbol |
Returns
Function
[]
Since
v0.1.26
Inherited from
Client.listeners
Defined in
node_modules/@types/node/events.d.ts:752
login
▸ login(token?
): Promise
<string
>
Loads all pieces, then logs the client in, establishing a websocket connection to Discord.
Parameters
Name | Type | Description |
---|---|---|
token? | string | Token of the account to log in with. |
Returns
Promise
<string
>
Token of the account used.
Since
1.0.0
Overrides
Client.login
Defined in
projects/framework/src/lib/SapphireClient.ts:338
off
▸ off<Event
>(event
, listener
): this
Type parameters
Name | Type |
---|---|
Event | extends keyof ClientEvents |
Parameters
Name | Type |
---|---|
event | Event |
listener | (...args : ClientEvents [Event ]) => Awaitable <void > |
Returns
this
Inherited from
Client.off
Defined in
node_modules/discord.js/typings/index.d.ts:1024
▸ off<Event
>(event
, listener
): this
Type parameters
Name | Type |
---|---|
Event | extends string | symbol |
Parameters
Name | Type |
---|---|
event | Exclude <Event , keyof ClientEvents > |
listener | (...args : any []) => Awaitable <void > |
Returns
this
Inherited from
Client.off
Defined in
node_modules/discord.js/typings/index.d.ts:1028
on
▸ on<Event
>(event
, listener
): this
Type parameters
Name | Type |
---|---|
Event | extends keyof ClientEvents |
Parameters
Name | Type |
---|---|
event | Event |
listener | (...args : ClientEvents [Event ]) => Awaitable <void > |
Returns
this
Inherited from
Client.on
Defined in
node_modules/discord.js/typings/index.d.ts:1003
▸ on<Event
>(event
, listener
): this
Type parameters
Name | Type |
---|---|
Event | extends string | symbol |
Parameters
Name | Type |
---|---|
event | Exclude <Event , keyof ClientEvents > |
listener | (...args : any []) => Awaitable <void > |
Returns
this
Inherited from
Client.on
Defined in
node_modules/discord.js/typings/index.d.ts:1007
once
▸ once<Event
>(event
, listener
): this
Type parameters
Name | Type |
---|---|
Event | extends keyof ClientEvents |
Parameters
Name | Type |
---|---|
event | Event |
listener | (...args : ClientEvents [Event ]) => Awaitable <void > |
Returns
this
Inherited from
Client.once
Defined in
node_modules/discord.js/typings/index.d.ts:1012
▸ once<Event
>(event
, listener
): this
Type parameters
Name | Type |
---|---|
Event | extends string | symbol |
Parameters
Name | Type |
---|---|
event | Exclude <Event , keyof ClientEvents > |
listener | (...args : any []) => Awaitable <void > |
Returns
this
Inherited from
Client.once
Defined in
node_modules/discord.js/typings/index.d.ts:1016
prependListener
▸ prependListener<K
>(eventName
, listener
): this
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.
Type parameters
Name |
---|
K |
Parameters
Name | Type | Description |
---|---|---|
eventName | string | symbol | The name of the event. |
listener | (...args : any []) => void | The callback function |
Returns
this
Since
v6.0.0
Inherited from
Client.prependListener
Defined in
node_modules/@types/node/events.d.ts:851
prependOnceListener
▸ prependOnceListener<K
>(eventName
, listener
): this
Adds a one-timelistener
function for the event named eventName
to the beginning 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.
Type parameters
Name |
---|
K |
Parameters
Name | Type | Description |
---|---|---|
eventName | string | symbol | The name of the event. |
listener | (...args : any []) => void | The callback function |
Returns
this
Since
v6.0.0
Inherited from
Client.prependOnceListener
Defined in
node_modules/@types/node/events.d.ts:867
rawListeners
▸ rawListeners<K
>(eventName
): Function
[]
Returns a copy of the array of listeners for the event named eventName
,
including any wrappers (such as those created by .once()
).
import { EventEmitter } from 'node:events';
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');
Type parameters
Name |
---|
K |
Parameters
Name | Type |
---|---|
eventName | string | symbol |
Returns
Function
[]
Since
v9.4.0
Inherited from
Client.rawListeners
Defined in
node_modules/@types/node/events.d.ts:783
removeAllListeners
▸ removeAllListeners<Event
>(event?
): this
Type parameters
Name | Type |
---|---|
Event | extends keyof ClientEvents |
Parameters
Name | Type |
---|---|
event? | Event |
Returns
this
Inherited from
Client.removeAllListeners
Defined in
node_modules/discord.js/typings/index.d.ts:1033
▸ removeAllListeners<Event
>(event?
): this
Type parameters
Name | Type |
---|---|
Event | extends string | symbol |
Parameters
Name | Type |
---|---|
event? | Exclude <Event , keyof ClientEvents > |
Returns
this
Inherited from
Client.removeAllListeners
Defined in
node_modules/discord.js/typings/index.d.ts:1034
removeListener
▸ removeListener<K
>(eventName
, listener
): this
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 and before the last listener finishes execution
will not remove them fromemit()
in progress. Subsequent events behave as expected.
import { EventEmitter } from 'node:events';
class MyEmitter extends EventEmitter {}
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:
import { EventEmitter } from 'node:events';
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.
Type parameters
Name |
---|
K |
Parameters
Name | Type |
---|---|
eventName | string | symbol |
listener | (...args : any []) => void |
Returns
this
Since
v0.1.26
Inherited from
Client.removeListener
Defined in
node_modules/@types/node/events.d.ts:707
setMaxListeners
▸ setMaxListeners(n
): this
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.
Parameters
Name | Type |
---|---|
n | number |
Returns
this
Since
v0.3.5
Inherited from
Client.setMaxListeners
Defined in
node_modules/@types/node/events.d.ts:733
toJSON
▸ toJSON(): unknown
Returns
unknown
Inherited from
Client.toJSON
Defined in
node_modules/discord.js/typings/index.d.ts:1001
addAbortListener
▸ addAbortListener(signal
, resource
): Disposable
Listens once to the abort
event on the provided signal
.
Listening to the abort
event on abort signals is unsafe and may
lead to resource leaks since another third party with the signal can
call e.stopImmediatePropagation()
. Unfortunately Node.js cannot change
this since it would violate the web standard. Additionally, the original
API makes it easy to forget to remove listeners.
This API allows safely using AbortSignal
s in Node.js APIs by solving these
two issues by listening to the event such that stopImmediatePropagation
does
not prevent the listener from running.
Returns a disposable so that it may be unsubscribed from more easily.
import { addAbortListener } from 'node:events';
function example(signal) {
let disposable;
try {
signal.addEventListener('abort', (e) => e.stopImmediatePropagation());
disposable = addAbortListener(signal, (e) => {
// Do something when signal is aborted.
});
} finally {
disposable?.[Symbol.dispose]();
}
}
Parameters
Name | Type |
---|---|
signal | AbortSignal |
resource | (event : Event ) => void |
Returns
Disposable
Disposable that removes the abort
listener.
Since
v20.5.0
Inherited from
Client.addAbortListener
Defined in
node_modules/@types/node/events.d.ts:404
getEventListeners
▸ 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.
import { getEventListeners, EventEmitter } from 'node:events';
{
const ee = new EventEmitter();
const listener = () => console.log('Events are fun');
ee.on('foo', listener);
console.log(getEventListeners(ee, 'foo')); // [ [Function: listener] ]
}
{
const et = new EventTarget();
const listener = () => console.log('Events are fun');
et.addEventListener('foo', listener);
console.log(getEventListeners(et, 'foo')); // [ [Function: listener] ]
}
Parameters
Name | Type |
---|---|
emitter | EventEmitter <DefaultEventMap > | _DOMEventTarget |
name | string | symbol |
Returns
Function
[]
Since
v15.2.0, v14.17.0
Inherited from
Client.getEventListeners
Defined in
node_modules/@types/node/events.d.ts:325
getMaxListeners
▸ getMaxListeners(emitter
): number
Returns the currently set max amount of listeners.
For EventEmitter
s this behaves exactly the same as calling .getMaxListeners
on
the emitter.
For EventTarget
s this is the only way to get the max event listeners for the
event target. If the number of event handlers on a single EventTarget exceeds
the max set, the EventTarget will print a warning.
import { getMaxListeners, setMaxListeners, EventEmitter } from 'node:events';
{
const ee = new EventEmitter();
console.log(getMaxListeners(ee)); // 10
setMaxListeners(11, ee);
console.log(getMaxListeners(ee)); // 11
}
{
const et = new EventTarget();
console.log(getMaxListeners(et)); // 10
setMaxListeners(11, et);
console.log(getMaxListeners(et)); // 11
}
Parameters
Name | Type |
---|---|
emitter | EventEmitter <DefaultEventMap > | _DOMEventTarget |
Returns
number
Since
v19.9.0
Inherited from
Client.getMaxListeners
Defined in
node_modules/@types/node/events.d.ts:354
listenerCount
▸ listenerCount(emitter
, eventName
): number
A class method that returns the number of listeners for the given eventName
registered on the given emitter
.
import { EventEmitter, listenerCount } from 'node:events';
const myEmitter = new EventEmitter();
myEmitter.on('event', () => {});
myEmitter.on('event', () => {});
console.log(listenerCount(myEmitter, 'event'));
// Prints: 2
Parameters
Name | Type | Description |
---|---|---|
emitter | EventEmitter <DefaultEventMap > | The emitter to query |
eventName | string | symbol | The event name |
Returns
number
Since
v0.9.12
Deprecated
Since v3.2.0 - Use listenerCount
instead.
Inherited from
Client.listenerCount
Defined in
node_modules/@types/node/events.d.ts:297
on
▸ on(emitter
, eventName
, options?
): AsyncIterableIterator
<any
>
import { on, EventEmitter } from 'node:events';
import process from 'node:process';
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:
import { on, EventEmitter } from 'node:events';
import process from 'node:process';
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());
Parameters
Name | Type | Description |
---|---|---|
emitter | EventEmitter <DefaultEventMap > | - |
eventName | string | The name of the event being listened for |
options? | StaticEventEmitterOptions | - |
Returns
AsyncIterableIterator
<any
>
that iterates eventName
events emitted by the emitter
Since
v13.6.0, v12.16.0
Inherited from
Client.on
Defined in
node_modules/@types/node/events.d.ts:275
▸ on<Emitter
, Events
>(eventEmitter
, eventName
): AsyncIterableIterator
<Emitter
extends Client
<boolean
> ? ClientEvents
[Events
] : any
>
Type parameters
Name | Type |
---|---|
Emitter | extends __module |
Events | extends keyof ClientEvents |
Parameters
Name | Type |
---|---|
eventEmitter | Emitter |
eventName | Emitter extends Client <boolean > ? Events : string |
Returns
AsyncIterableIterator
<Emitter
extends Client
<boolean
> ? ClientEvents
[Events
] : any
>
Inherited from
Client.on
Defined in
node_modules/discord.js/typings/index.d.ts:243
once
▸ 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.
import { once, EventEmitter } from 'node:events';
import process from 'node:process';
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.error('error happened', err);
}
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:
import { EventEmitter, once } from 'node:events';
const ee = new EventEmitter();
once(ee, 'error')
.then(([err]) => console.log('ok', err.message))
.catch((err) => console.error('error', err.message));
ee.emit('error', new Error('boom'));
// Prints: ok boom
An AbortSignal
can be used to cancel waiting for the event:
import { EventEmitter, once } from 'node: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!
Parameters
Name | Type |
---|---|
emitter | _NodeEventTarget |
eventName | string | symbol |
options? | StaticEventEmitterOptions |
Returns
Promise
<any
[]>
Since
v11.13.0, v10.16.0
Inherited from
Client.once
Defined in
node_modules/@types/node/events.d.ts:210
▸ 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:215
▸ once<Emitter
, Event
>(eventEmitter
, eventName
): Promise
<Emitter
extends Client
<boolean
> ? ClientEvents
[Event
] : any
[]>
Type parameters
Name | Type |
---|---|
Emitter | extends __module |
Event | extends keyof ClientEvents |
Parameters
Name | Type |
---|---|
eventEmitter | Emitter |
eventName | Emitter extends Client <boolean > ? Event : string |
Returns
Promise
<Emitter
extends Client
<boolean
> ? ClientEvents
[Event
] : any
[]>
Inherited from
Client.once
Defined in
node_modules/discord.js/typings/index.d.ts:239
setMaxListeners
▸ setMaxListeners(n?
, ...eventTargets
): void
import { setMaxListeners, EventEmitter } from 'node:events';
const target = new EventTarget();
const emitter = new EventEmitter();
setMaxListeners(5, target, emitter);
Parameters
Name | Type | Description |
---|---|---|
n? | number | A non-negative number. The maximum number of listeners per EventTarget event. |
...eventTargets | (EventEmitter <DefaultEventMap > | _DOMEventTarget )[] | - |
Returns
void
Since
v15.4.0
Inherited from
Client.setMaxListeners
Defined in
node_modules/@types/node/events.d.ts:369
use
▸ use(plugin
): typeof SapphireClient
Parameters
Name | Type |
---|---|
plugin | typeof Plugin |
Returns
typeof SapphireClient