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Class: Listener<E, O>

The base event class. This class is abstract and is to be extended by subclasses, which should implement the methods. In Sapphire's workflow, listeners are called when the emitter they listen on emits a new message with the same event name.

Example

// TypeScript:
import { Events, Listener } from '@sapphire/framework';

// Define a class extending `Listener`, then export it.
// NOTE: You can use `export default` or `export =` too.
export class CoreListener extends Listener<typeof Events.ClientReady> {
  public constructor(context: Listener.Context) {
    super(context, { event: Events.ClientReady, once: true });
  }

  public run() {
    this.container.client.id ??= this.container.client.user?.id ?? null;
  }
}

Example

// JavaScript:
const { Events, Listener } = require('@sapphire/framework');

// Define a class extending `Listener`, then export it.
module.exports = class CoreListener extends Listener {
  constructor(context) {
    super(context, { event: Events.ClientReady, once: true });
  }

  run() {
    this.container.client.id ??= this.container.client.user?.id ?? null;
  }
}

Type parameters​

NameType
Eextends keyof ClientEvents | symbol = ""
Oextends Options = Options

Hierarchy​

Constructors​

constructor​

• new Listener<E, O>(context, options?)

Type parameters​

NameType
Eextends symbol | keyof ClientEvents = ""
Oextends ListenerOptions<O> = ListenerOptions

Parameters​

NameType
contextPieceContext
optionsO

Overrides​

Piece.constructor

Defined in​

projects/framework/src/lib/structures/Listener.ts:73

Properties​

_listener​

• Private _listener: null | (...args: any[]) => void

Defined in​

projects/framework/src/lib/structures/Listener.ts:71

emitter​

• Readonly emitter: null | __module

The emitter, if any.

Since

2.0.0

Defined in​

projects/framework/src/lib/structures/Listener.ts:57

enabled​

• enabled: boolean

Whether or not the piece is enabled.

Inherited from​

Piece.enabled

Defined in​

node_modules/@sapphire/pieces/dist/index.d.ts:450

event​

• Readonly event: string | symbol

The name of the event the listener listens to.

Since

2.0.0

Defined in​

projects/framework/src/lib/structures/Listener.ts:63

location​

• Readonly location: PieceLocation

The location metadata for the piece's file.

Inherited from​

Piece.location

Defined in​

node_modules/@sapphire/pieces/dist/index.d.ts:442

name​

• Readonly name: string

The name of the piece.

Inherited from​

Piece.name

Defined in​

node_modules/@sapphire/pieces/dist/index.d.ts:446

once​

• Readonly once: boolean

Whether the listener will be unloaded after the first run.

Since

2.0.0

Defined in​

projects/framework/src/lib/structures/Listener.ts:69

options​

• Readonly options: O

The raw options passed to this Piece

Inherited from​

Piece.options

Defined in​

node_modules/@sapphire/pieces/dist/index.d.ts:454

store​

• store: ListenerStore

The ListenerStore that contains this Listener.

Overrides​

Piece.store

Defined in​

projects/framework/src/lib/structures/Listener.ts:51

Accessors​

container​

• get container(): Container

A reference to the Container object for ease of use.

See

container

Returns​

Container

Inherited from​

Piece.container

Defined in​

node_modules/@sapphire/pieces/dist/index.d.ts:460

Methods​

_run​

▸ Private _run(...args): Promise<void>

Parameters​

NameType
...argsunknown[]

Returns​

Promise<void>

Defined in​

projects/framework/src/lib/structures/Listener.ts:128

_runOnce​

▸ Private _runOnce(...args): Promise<void>

Parameters​

NameType
...argsunknown[]

Returns​

Promise<void>

Defined in​

projects/framework/src/lib/structures/Listener.ts:133

onLoad​

▸ onLoad(): unknown

Per-piece listener that is called when the piece is loaded into the store. Useful to set-up asynchronous initialization tasks.

Returns​

unknown

Overrides​

Piece.onLoad

Defined in​

projects/framework/src/lib/structures/Listener.ts:92

onUnload​

▸ onUnload(): unknown

Per-piece listener that is called when the piece is unloaded from the store. Useful to set-up clean-up tasks.

Returns​

unknown

Overrides​

Piece.onUnload

Defined in​

projects/framework/src/lib/structures/Listener.ts:105

reload​

▸ reload(): Promise<void>

Reloads the piece by loading the same path in the store.

Returns​

Promise<void>

Inherited from​

Piece.reload

Defined in​

node_modules/@sapphire/pieces/dist/index.d.ts:478

run​

▸ Abstract run(...args): unknown

Parameters​

NameType
...argsE extends keyof ClientEvents ? ClientEvents[E] : unknown[]

Returns​

unknown

Defined in​

projects/framework/src/lib/structures/Listener.ts:90

toJSON​

▸ toJSON(): ListenerJSON

Defines the JSON.stringify behavior of this piece.

Returns​

ListenerJSON

Overrides​

Piece.toJSON

Defined in​

projects/framework/src/lib/structures/Listener.ts:120

unload​

▸ unload(): Promise<void>

Unloads and disables the piece.

Returns​

Promise<void>

Inherited from​

Piece.unload

Defined in​

node_modules/@sapphire/pieces/dist/index.d.ts:474