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DBPFEntry

DBPF.js v1.1.0 • Docs

DBPF.js v1.1.0 / DBPF / DBPFEntry

Class: DBPFEntry

The DBPF Entry class.

It is a representation of a DBPF resource.

Extends​

Constructors​

new DBPFEntry()​

new DBPFEntry(DBPF, type, group, instance, offset, size): DBPFEntry

Parameters​

• DBPF: DBPF

• type: number

• group: number

• instance: number | bigint

• offset: number

• size

• size.file

• size.file.raw: number

• size.file.reduced: number

• size.flag?: number

• size.memory?: number

Returns​

DBPFEntry

Overrides​

EventEmitter.constructor

Defined in​

src/DBPF.ts:1023

Properties​

_DBPF​

private _DBPF: DBPF

Defined in​

src/DBPF.ts:1065

/ _blob​

private _blob: undefined | Blob

Defined in​

src/DBPF.ts:1135

blob()​

blob: (refresh?) => Promise<Blob>

Retrive the DBPF resource as a Blob on demand. This is a memory-efficient way to handle the blobs read from the entry.

NOTE: This method is designed to be overwritten by plugins. While it is an option, it is not recommended, as overwriting this method in one plugin may break it for other plugins.

Parameters​

• refresh?: boolean

Whether to refresh the blob. If set to true, the blob will be re-read from the entry.

Returns​

Promise<Blob>

A promise that resolves with a Blob of the DBPF resource.

Defined in​

src/DBPF.ts:1121

group​

readonly group: number

The group id of the DBPF resource.

Defined in​

src/DBPF.ts:1074

init​

init: undefined | () => EventedPromise<void>

Initializes the DBPF Entry asynchronously, evented.

Defined in​

src/DBPF.ts:1063

instance​

readonly instance: number | bigint

The instance id of the DBPF resource.

Defined in​

src/DBPF.ts:1079

mimetype​

mimetype: undefined | string

Defined in​

src/DBPF.ts:1111

offset​

readonly offset: number

The offset of the DBPF resource in the DBPF file.

Defined in​

src/DBPF.ts:1083

reader​

readonly reader: BufferReader

The buffer reader for the DBPF resource.

Defined in​

src/DBPF.ts:1110

size​

readonly size: object

The compression information about the DBPF resource.

file​

file: object

The amount of bytes the DBPF resource takes up in the DBPF file.

file.raw​

raw: number

file.reduced​

reduced: number

flag?​

optional flag: number

The compression flag of the DBPF resource.

memory?​

optional memory: number

The amount of bytes the DBPF resource takes up uncompressed in memory.

Defined in​

src/DBPF.ts:1088

type​

readonly type: number

The type id of the DBPF resource.

Defined in​

src/DBPF.ts:1070

captureRejectionSymbol​

readonly static 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​

EventEmitter.captureRejectionSymbol

Defined in​

node_modules/@types/node/events.d.ts:452

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​

EventEmitter.captureRejections

Defined in​

node_modules/@types/node/events.d.ts:459

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 all EventEmitter 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 single EventEmitter, 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​

EventEmitter.defaultMaxListeners

Defined in​

node_modules/@types/node/events.d.ts:498

errorMonitor​

readonly static 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​

EventEmitter.errorMonitor

Defined in​

node_modules/@types/node/events.d.ts:445

Methods​

[captureRejectionSymbol]()?​

optional [captureRejectionSymbol]<K>(error, event, ...args): void

Type Parameters​

• K

Parameters​

• error: Error

• event: string | symbol

• ...args: AnyRest

Returns​

void

Inherited from​

EventEmitter.[captureRejectionSymbol]

Defined in​

node_modules/@types/node/events.d.ts:136

addListener()​

addListener<K>(eventName, listener): this

Alias for emitter.on(eventName, listener).

Type Parameters​

• K

Parameters​

• eventName: string | symbol

• listener

Returns​

this

Since​

v0.1.26

Inherited from​

EventEmitter.addListener

Defined in​

node_modules/@types/node/events.d.ts:597

emit()​

emit<K>(eventName, ...args): boolean

Synchronously calls each of the listeners registered for the event named eventName, in the order they were registered, passing the supplied arguments to each.

Returns true if the event had listeners, false otherwise.

import { EventEmitter } from 'node:events';
const myEmitter = new EventEmitter();

// First listener
myEmitter.on('event', function firstListener() {
  console.log('Helloooo! first listener');
});
// Second listener
myEmitter.on('event', function secondListener(arg1, arg2) {
  console.log(`event with parameters ${arg1}, ${arg2} in second listener`);
});
// Third listener
myEmitter.on('event', function thirdListener(...args) {
  const parameters = args.join(', ');
  console.log(`event with parameters ${parameters} in third listener`);
});

console.log(myEmitter.listeners('event'));

myEmitter.emit('event', 1, 2, 3, 4, 5);

// Prints:
// [
//   [Function: firstListener],
//   [Function: secondListener],
//   [Function: thirdListener]
// ]
// Helloooo! first listener
// event with parameters 1, 2 in second listener
// event with parameters 1, 2, 3, 4, 5 in third listener

Type Parameters​

• K

Parameters​

• eventName: string | symbol

• ...args: AnyRest

Returns​

boolean

Since​

v0.1.26

Inherited from​

EventEmitter.emit

Defined in​

node_modules/@types/node/events.d.ts:859

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.

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​

EventEmitter.eventNames

Defined in​

node_modules/@types/node/events.d.ts:922

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​

EventEmitter.getMaxListeners

Defined in​

node_modules/@types/node/events.d.ts:774

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​

• K

Parameters​

• 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​

EventEmitter.listenerCount

Defined in​

node_modules/@types/node/events.d.ts:868

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​

• K

Parameters​

• eventName: string | symbol

Returns​

Function[]

Since​

v0.1.26

Inherited from​

EventEmitter.listeners

Defined in​

node_modules/@types/node/events.d.ts:787

off()​

off<K>(eventName, listener): this

Alias for emitter.removeListener().

Type Parameters​

• K

Parameters​

• eventName: string | symbol

• listener

Returns​

this

Since​

v10.0.0

Inherited from​

EventEmitter.off

Defined in​

node_modules/@types/node/events.d.ts:747

on()​

on<K>(eventName, listener): this

Adds the listener function to the end 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.on('connection', (stream) => {
  console.log('someone connected!');
});

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

By default, event listeners are invoked in the order they are added. The emitter.prependListener() method can be used as an alternative to add the event listener to the beginning of the listeners array.

import { EventEmitter } from 'node:events';
const myEE = new EventEmitter();
myEE.on('foo', () => console.log('a'));
myEE.prependListener('foo', () => console.log('b'));
myEE.emit('foo');
// Prints:
//   b
//   a

Type Parameters​

• K

Parameters​

• eventName: string | symbol

The name of the event.

• listener

The callback function

Returns​

this

Since​

v0.1.101

Inherited from​

EventEmitter.on

Defined in​

node_modules/@types/node/events.d.ts:629

once()​

once<K>(eventName, listener): this

Adds a one-time listener function for the event named eventName. The next time eventName is triggered, this listener is removed and then invoked.

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

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

By default, event listeners are invoked in the order they are added. The emitter.prependOnceListener() method can be used as an alternative to add the event listener to the beginning of the listeners array.

import { EventEmitter } from 'node:events';
const myEE = new EventEmitter();
myEE.once('foo', () => console.log('a'));
myEE.prependOnceListener('foo', () => console.log('b'));
myEE.emit('foo');
// Prints:
//   b
//   a

Type Parameters​

• K

Parameters​

• eventName: string | symbol

The name of the event.

• listener

The callback function

Returns​

this

Since​

v0.3.0

Inherited from​

EventEmitter.once

Defined in​

node_modules/@types/node/events.d.ts:659

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​

• K

Parameters​

• eventName: string | symbol

The name of the event.

• listener

The callback function

Returns​

this

Since​

v6.0.0

Inherited from​

EventEmitter.prependListener

Defined in​

node_modules/@types/node/events.d.ts:886

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​

• K

Parameters​

• eventName: string | symbol

The name of the event.

• listener

The callback function

Returns​

this

Since​

v6.0.0

Inherited from​

EventEmitter.prependOnceListener

Defined in​

node_modules/@types/node/events.d.ts:902

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​

• K

Parameters​

• eventName: string | symbol

Returns​

Function[]

Since​

v9.4.0

Inherited from​

EventEmitter.rawListeners

Defined in​

node_modules/@types/node/events.d.ts:818

removeAllListeners()​

removeAllListeners(eventName?): this

Removes all listeners, or those of the specified eventName.

It is bad practice to remove listeners added elsewhere in the code, particularly when the EventEmitter instance was created by some other component or module (e.g. sockets or file streams).

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

Parameters​

• eventName?: string | symbol

Returns​

this

Since​

v0.1.26

Inherited from​

EventEmitter.removeAllListeners

Defined in​

node_modules/@types/node/events.d.ts:758

removeListener()​

removeListener<K>(eventName, listener): this

Removes the specified listener from the listener array for the event named eventName.

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 any removeListener() 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​

• K

Parameters​

• eventName: string | symbol

• listener

Returns​

this

Since​

v0.1.26

Inherited from​

EventEmitter.removeListener

Defined in​

node_modules/@types/node/events.d.ts:742

setMaxListeners()​

setMaxListeners(n): this

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 to Infinity (or 0) to indicate an unlimited number of listeners.

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

Parameters​

• n: number

Returns​

this

Since​

v0.3.5

Inherited from​

EventEmitter.setMaxListeners

Defined in​

node_modules/@types/node/events.d.ts:768

addAbortListener()​

static addAbortListener(signal, resource): Disposable

Experimental

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 AbortSignals 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​

• signal: AbortSignal

• resource

Returns​

Disposable

Disposable that removes the abort listener.

Since​

v20.5.0

Inherited from​

EventEmitter.addAbortListener

Defined in​

node_modules/@types/node/events.d.ts:437

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.

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​

• emitter: EventTarget | EventEmitter<DefaultEventMap>

• name: string | symbol

Returns​

Function[]

Since​

v15.2.0, v14.17.0

Inherited from​

EventEmitter.getEventListeners

Defined in​

node_modules/@types/node/events.d.ts:358

getMaxListeners()​

static getMaxListeners(emitter): number

Returns the currently set max amount of listeners.

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

For EventTargets 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​

• emitter: EventTarget | EventEmitter<DefaultEventMap>

Returns​

number

Since​

v19.9.0

Inherited from​

EventEmitter.getMaxListeners

Defined in​

node_modules/@types/node/events.d.ts:387

listenerCount()​

static 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​

• 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​

EventEmitter.listenerCount

Defined in​

node_modules/@types/node/events.d.ts:330

on()​

on(emitter, eventName, options)​

static 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());

Use the close option to specify an array of event names that will end the iteration:

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);
  ee.emit('close');
});

for await (const event of on(ee, 'foo', { close: ['close'] })) {
  console.log(event); // prints ['bar'] [42]
}
// the loop will exit after 'close' is emitted
console.log('done'); // prints 'done'
Parameters​

• emitter: EventEmitter<DefaultEventMap>

• eventName: string | symbol

• options?: StaticEventEmitterIteratorOptions

Returns​

AsyncIterableIterator<any[]>

An AsyncIterator that iterates eventName events emitted by the emitter

Since​

v13.6.0, v12.16.0

Inherited from​

EventEmitter.on

Defined in​

node_modules/@types/node/events.d.ts:303

on(emitter, eventName, options)​

static on(emitter, eventName, options?): AsyncIterableIterator<any[]>

Parameters​

• emitter: EventTarget

• eventName: string

• options?: StaticEventEmitterIteratorOptions

Returns​

AsyncIterableIterator<any[]>

Inherited from​

EventEmitter.on

Defined in​

node_modules/@types/node/events.d.ts:308

once()​

once(emitter, eventName, options)​

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.

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​

• emitter: EventEmitter<DefaultEventMap>

• eventName: string | symbol

• options?: StaticEventEmitterOptions

Returns​

Promise<any[]>

Since​

v11.13.0, v10.16.0

Inherited from​

EventEmitter.once

Defined in​

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

once(emitter, eventName, options)​

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

Parameters​

• emitter: EventTarget

• eventName: string

• options?: StaticEventEmitterOptions

Returns​

Promise<any[]>

Inherited from​

EventEmitter.once

Defined in​

node_modules/@types/node/events.d.ts:222

setMaxListeners()​

static setMaxListeners(n?, ...eventTargets?): void

import { setMaxListeners, EventEmitter } from 'node:events';

const target = new EventTarget();
const emitter = new EventEmitter();

setMaxListeners(5, target, emitter);

Parameters​

• n?: number

A non-negative number. The maximum number of listeners per EventTarget event.

• ...eventTargets?: (EventTarget | EventEmitter<DefaultEventMap>)[]

Returns​

void

Since​

v15.4.0

Inherited from​

EventEmitter.setMaxListeners

Defined in​

node_modules/@types/node/events.d.ts:402

Events​

ON_ERROR​

readonly static ON_ERROR: "error" = "error"

The event name for when the DBPF Entry encounters an error.

Defined in​

src/DBPF.ts:1058

ON / _INIT​

readonly static ON_INIT: "init" = "init"

The event name for when the DBPF Entry is initialized.

Defined in​

src/DBPF.ts:1053

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