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Documents for @litert/websocket / MessageReadStream / WsMessageReadStream

Class: WsMessageReadStream

Defined in: src/lib/MessageReadStream.ts:22

The interface of websocket message reader, implements Readable stream.

Extends

  • Readable

Implements

Constructors

Constructor

new WsMessageReadStream(opcode): WsMessageReadStream

Defined in: src/lib/MessageReadStream.ts:26

Parameters

opcode

EOpcode

Returns

WsMessageReadStream

Overrides

Readable.constructor

Properties

closed

readonly closed: boolean

Defined in: node_modules/@types/node/stream.d.ts:157

Is true after 'close' has been emitted.

Since

v18.0.0

Implementation of

dL.IMessageReadStream.closed

Inherited from

Readable.closed


destroyed

destroyed: boolean

Defined in: node_modules/@types/node/stream.d.ts:152

Is true after readable.destroy() has been called.

Since

v8.0.0

Implementation of

dL.IMessageReadStream.destroyed

Inherited from

Readable.destroyed


errored

readonly errored: Error | null

Defined in: node_modules/@types/node/stream.d.ts:162

Returns error if the stream has been destroyed with an error.

Since

v18.0.0

Implementation of

dL.IMessageReadStream.errored

Inherited from

Readable.errored


mode

readonly mode: STANDARD = cL.EFrameReceiveMode.STANDARD

Defined in: src/lib/MessageReadStream.ts:24

The mode of receiving frames. Only and always for EFrameReceiveMode.STANDARD.

Implementation of

IMessageReadStream.mode


opcode

readonly opcode: EOpcode

Defined in: src/lib/MessageReadStream.ts:27

The opcode of this message.

Implementation of

IMessageReadStream.opcode


readable

readable: boolean

Defined in: node_modules/@types/node/stream.d.ts:109

Is true if it is safe to call read, which means the stream has not been destroyed or emitted 'error' or 'end'.

Since

v11.4.0

Implementation of

dL.IMessageReadStream.readable

Inherited from

Readable.readable


readableAborted

readonly readableAborted: boolean

Defined in: node_modules/@types/node/stream.d.ts:103

Returns whether the stream was destroyed or errored before emitting 'end'.

Since

v16.8.0

Implementation of

dL.IMessageReadStream.readableAborted

Inherited from

Readable.readableAborted


readableDidRead

readonly readableDidRead: boolean

Defined in: node_modules/@types/node/stream.d.ts:114

Returns whether 'data' has been emitted.

Since

v16.7.0, v14.18.0

Implementation of

dL.IMessageReadStream.readableDidRead

Inherited from

Readable.readableDidRead


readableEncoding

readonly readableEncoding: BufferEncoding | null

Defined in: node_modules/@types/node/stream.d.ts:119

Getter for the property encoding of a given Readable stream. The encoding property can be set using the setEncoding method.

Since

v12.7.0

Implementation of

dL.IMessageReadStream.readableEncoding

Inherited from

Readable.readableEncoding


readableEnded

readonly readableEnded: boolean

Defined in: node_modules/@types/node/stream.d.ts:124

Becomes true when 'end' event is emitted.

Since

v12.9.0

Implementation of

dL.IMessageReadStream.readableEnded

Inherited from

Readable.readableEnded


readableFlowing

readonly readableFlowing: boolean | null

Defined in: node_modules/@types/node/stream.d.ts:130

This property reflects the current state of a Readable stream as described in the Three states section.

Since

v9.4.0

Implementation of

dL.IMessageReadStream.readableFlowing

Inherited from

Readable.readableFlowing


readableHighWaterMark

readonly readableHighWaterMark: number

Defined in: node_modules/@types/node/stream.d.ts:135

Returns the value of highWaterMark passed when creating this Readable.

Since

v9.3.0

Implementation of

dL.IMessageReadStream.readableHighWaterMark

Inherited from

Readable.readableHighWaterMark


readableLength

readonly readableLength: number

Defined in: node_modules/@types/node/stream.d.ts:142

This property contains the number of bytes (or objects) in the queue ready to be read. The value provides introspection data regarding the status of the highWaterMark.

Since

v9.4.0

Implementation of

dL.IMessageReadStream.readableLength

Inherited from

Readable.readableLength


readableObjectMode

readonly readableObjectMode: boolean

Defined in: node_modules/@types/node/stream.d.ts:147

Getter for the property objectMode of a given Readable stream.

Since

v12.3.0

Implementation of

dL.IMessageReadStream.readableObjectMode

Inherited from

Readable.readableObjectMode


captureRejections

static captureRejections: boolean

Defined in: node_modules/@types/node/events.d.ts:425

Value: boolean

Change the default captureRejections option on all new EventEmitter objects.

Since

v13.4.0, v12.16.0

Inherited from

Readable.captureRejections


captureRejectionSymbol

readonly static captureRejectionSymbol: typeof captureRejectionSymbol

Defined in: node_modules/@types/node/events.d.ts:418

Value: Symbol.for('nodejs.rejection')

See how to write a custom rejection handler.

Since

v13.4.0, v12.16.0

Inherited from

Readable.captureRejectionSymbol


defaultMaxListeners

static defaultMaxListeners: number

Defined in: node_modules/@types/node/events.d.ts:464

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:

js
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

Readable.defaultMaxListeners


errorMonitor

readonly static errorMonitor: typeof errorMonitor

Defined in: node_modules/@types/node/events.d.ts:411

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

Readable.errorMonitor

Methods

_construct()?

optional _construct(callback): void

Defined in: node_modules/@types/node/stream.d.ts:164

Parameters

callback

(error?) => void

Returns

void

Implementation of

dL.IMessageReadStream._construct

Inherited from

Readable._construct


_destroy()

_destroy(error, callback): void

Defined in: node_modules/@types/node/stream.d.ts:605

Parameters

error

Error | null

callback

(error?) => void

Returns

void

Implementation of

dL.IMessageReadStream._destroy

Inherited from

Readable._destroy


_read()

_read(): void

Defined in: src/lib/MessageReadStream.ts:34

Returns

void

Implementation of

dL.IMessageReadStream._read

Overrides

Readable._read


[asyncDispose]()

[asyncDispose](): Promise<void>

Defined in: node_modules/@types/node/stream.d.ts:628

Calls readable.destroy() with an AbortError and returns a promise that fulfills when the stream is finished.

Returns

Promise<void>

Since

v20.4.0

Implementation of

dL.IMessageReadStream.[asyncDispose]

Inherited from

Readable.[asyncDispose]


[asyncIterator]()

[asyncIterator](): AsyncIterator<any>

Defined in: node_modules/@types/node/stream.d.ts:622

Returns

AsyncIterator<any>

AsyncIterator to fully consume the stream.

Since

v10.0.0

Implementation of

dL.IMessageReadStream.[asyncIterator]

Inherited from

Readable.[asyncIterator]


[captureRejectionSymbol]()?

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

Defined in: node_modules/@types/node/events.d.ts:103

Type Parameters

K

K

Parameters

error

Error

event

string | symbol

args

...AnyRest

Returns

void

Implementation of

dL.IMessageReadStream.[captureRejectionSymbol]

Inherited from

Readable.[captureRejectionSymbol]


addListener()

Call Signature

addListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:640

Event emitter The defined events on documents including:

  1. close
  2. data
  3. end
  4. error
  5. pause
  6. readable
  7. resume
Parameters
event

"close"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.addListener

Inherited from

Readable.addListener

Call Signature

addListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:641

Event emitter The defined events on documents including:

  1. close
  2. data
  3. end
  4. error
  5. pause
  6. readable
  7. resume
Parameters
event

"data"

listener

(chunk) => void

Returns

this

Implementation of

dL.IMessageReadStream.addListener

Inherited from

Readable.addListener

Call Signature

addListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:642

Event emitter The defined events on documents including:

  1. close
  2. data
  3. end
  4. error
  5. pause
  6. readable
  7. resume
Parameters
event

"end"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.addListener

Inherited from

Readable.addListener

Call Signature

addListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:643

Event emitter The defined events on documents including:

  1. close
  2. data
  3. end
  4. error
  5. pause
  6. readable
  7. resume
Parameters
event

"error"

listener

(err) => void

Returns

this

Implementation of

dL.IMessageReadStream.addListener

Inherited from

Readable.addListener

Call Signature

addListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:644

Event emitter The defined events on documents including:

  1. close
  2. data
  3. end
  4. error
  5. pause
  6. readable
  7. resume
Parameters
event

"pause"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.addListener

Inherited from

Readable.addListener

Call Signature

addListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:645

Event emitter The defined events on documents including:

  1. close
  2. data
  3. end
  4. error
  5. pause
  6. readable
  7. resume
Parameters
event

"readable"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.addListener

Inherited from

Readable.addListener

Call Signature

addListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:646

Event emitter The defined events on documents including:

  1. close
  2. data
  3. end
  4. error
  5. pause
  6. readable
  7. resume
Parameters
event

"resume"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.addListener

Inherited from

Readable.addListener

Call Signature

addListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:647

Event emitter The defined events on documents including:

  1. close
  2. data
  3. end
  4. error
  5. pause
  6. readable
  7. resume
Parameters
event

string | symbol

listener

(...args) => void

Returns

this

Implementation of

dL.IMessageReadStream.addListener

Inherited from

Readable.addListener


asIndexedPairs()

asIndexedPairs(options?): Readable

Defined in: node_modules/@types/node/stream.d.ts:580

This method returns a new stream with chunks of the underlying stream paired with a counter in the form [index, chunk]. The first index value is 0 and it increases by 1 for each chunk produced.

Parameters

options?

Pick<ArrayOptions, "signal">

Returns

Readable

a stream of indexed pairs.

Since

v17.5.0

Implementation of

dL.IMessageReadStream.asIndexedPairs

Inherited from

Readable.asIndexedPairs


compose()

compose<T>(stream, options?): T

Defined in: node_modules/@types/node/stream.d.ts:35

Type Parameters

T

T extends ReadableStream

Parameters

stream

T | ComposeFnParam | Iterable<T, any, any> | AsyncIterable<T, any, any>

options?
signal

AbortSignal

Returns

T

Implementation of

dL.IMessageReadStream.compose

Inherited from

Readable.compose


destroy()

destroy(error?): this

Defined in: node_modules/@types/node/stream.d.ts:617

Destroy the stream. Optionally emit an 'error' event, and emit a 'close' event (unless emitClose is set to false). After this call, the readable stream will release any internal resources and subsequent calls to push() will be ignored.

Once destroy() has been called any further calls will be a no-op and no further errors except from _destroy() may be emitted as 'error'.

Implementors should not override this method, but instead implement readable._destroy().

Parameters

error?

Error

Error which will be passed as payload in 'error' event

Returns

this

Since

v8.0.0

Implementation of

dL.IMessageReadStream.destroy

Inherited from

Readable.destroy


drop()

drop(limit, options?): Readable

Defined in: node_modules/@types/node/stream.d.ts:566

This method returns a new stream with the first limit chunks dropped from the start.

Parameters

limit

number

the number of chunks to drop from the readable.

options?

Pick<ArrayOptions, "signal">

Returns

Readable

a stream with limit chunks dropped from the start.

Since

v17.5.0

Implementation of

dL.IMessageReadStream.drop

Inherited from

Readable.drop


emit()

Call Signature

emit(event): boolean

Defined in: node_modules/@types/node/stream.d.ts:648

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.

js
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
Parameters
event

"close"

Returns

boolean

Since

v0.1.26

Implementation of

dL.IMessageReadStream.emit

Inherited from

Readable.emit

Call Signature

emit(event, chunk): boolean

Defined in: node_modules/@types/node/stream.d.ts:649

Parameters
event

"data"

chunk

any

Returns

boolean

Implementation of

dL.IMessageReadStream.emit

Inherited from

Readable.emit

Call Signature

emit(event): boolean

Defined in: node_modules/@types/node/stream.d.ts:650

Parameters
event

"end"

Returns

boolean

Implementation of

dL.IMessageReadStream.emit

Inherited from

Readable.emit

Call Signature

emit(event, err): boolean

Defined in: node_modules/@types/node/stream.d.ts:651

Parameters
event

"error"

err

Error

Returns

boolean

Implementation of

dL.IMessageReadStream.emit

Inherited from

Readable.emit

Call Signature

emit(event): boolean

Defined in: node_modules/@types/node/stream.d.ts:652

Parameters
event

"pause"

Returns

boolean

Implementation of

dL.IMessageReadStream.emit

Inherited from

Readable.emit

Call Signature

emit(event): boolean

Defined in: node_modules/@types/node/stream.d.ts:653

Parameters
event

"readable"

Returns

boolean

Implementation of

dL.IMessageReadStream.emit

Inherited from

Readable.emit

Call Signature

emit(event): boolean

Defined in: node_modules/@types/node/stream.d.ts:654

Parameters
event

"resume"

Returns

boolean

Implementation of

dL.IMessageReadStream.emit

Inherited from

Readable.emit

Call Signature

emit(event, ...args): boolean

Defined in: node_modules/@types/node/stream.d.ts:655

Parameters
event

string | symbol

args

...any[]

Returns

boolean

Implementation of

dL.IMessageReadStream.emit

Inherited from

Readable.emit


eventNames()

eventNames(): (string | symbol)[]

Defined in: node_modules/@types/node/events.d.ts:967

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

js
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

Implementation of

dL.IMessageReadStream.eventNames

Inherited from

Readable.eventNames


every()

every(fn, options?): Promise<boolean>

Defined in: node_modules/@types/node/stream.d.ts:545

This method is similar to Array.prototype.every and calls fn on each chunk in the stream to check if all awaited return values are truthy value for fn. Once an fn call on a chunk awaited return value is falsy, the stream is destroyed and the promise is fulfilled with false. If all of the fn calls on the chunks return a truthy value, the promise is fulfilled with true.

Parameters

fn

(data, options?) => boolean | Promise<boolean>

a function to call on each chunk of the stream. Async or not.

options?

ArrayOptions

Returns

Promise<boolean>

a promise evaluating to true if fn returned a truthy value for every one of the chunks.

Since

v17.5.0

Implementation of

dL.IMessageReadStream.every

Inherited from

Readable.every


filter()

filter(fn, options?): Readable

Defined in: node_modules/@types/node/stream.d.ts:473

This method allows filtering the stream. For each chunk in the stream the fn function will be called and if it returns a truthy value, the chunk will be passed to the result stream. If the fn function returns a promise - that promise will be awaited.

Parameters

fn

(data, options?) => boolean | Promise<boolean>

a function to filter chunks from the stream. Async or not.

options?

ArrayOptions

Returns

Readable

a stream filtered with the predicate fn.

Since

v17.4.0, v16.14.0

Implementation of

dL.IMessageReadStream.filter

Inherited from

Readable.filter


find()

Call Signature

find<T>(fn, options?): Promise<T | undefined>

Defined in: node_modules/@types/node/stream.d.ts:528

This method is similar to Array.prototype.find and calls fn on each chunk in the stream to find a chunk with a truthy value for fn. Once an fn call's awaited return value is truthy, the stream is destroyed and the promise is fulfilled with value for which fn returned a truthy value. If all of the fn calls on the chunks return a falsy value, the promise is fulfilled with undefined.

Type Parameters
T

T

Parameters
fn

(data, options?) => data is T

a function to call on each chunk of the stream. Async or not.

options?

ArrayOptions

Returns

Promise<T | undefined>

a promise evaluating to the first chunk for which fn evaluated with a truthy value, or undefined if no element was found.

Since

v17.5.0

Implementation of

dL.IMessageReadStream.find

Inherited from

Readable.find

Call Signature

find(fn, options?): Promise<any>

Defined in: node_modules/@types/node/stream.d.ts:532

This method is similar to Array.prototype.find and calls fn on each chunk in the stream to find a chunk with a truthy value for fn. Once an fn call's awaited return value is truthy, the stream is destroyed and the promise is fulfilled with value for which fn returned a truthy value. If all of the fn calls on the chunks return a falsy value, the promise is fulfilled with undefined.

Parameters
fn

(data, options?) => boolean | Promise<boolean>

a function to call on each chunk of the stream. Async or not.

options?

ArrayOptions

Returns

Promise<any>

a promise evaluating to the first chunk for which fn evaluated with a truthy value, or undefined if no element was found.

Since

v17.5.0

Implementation of

dL.IMessageReadStream.find

Inherited from

Readable.find


flatMap()

flatMap(fn, options?): Readable

Defined in: node_modules/@types/node/stream.d.ts:559

This method returns a new stream by applying the given callback to each chunk of the stream and then flattening the result.

It is possible to return a stream or another iterable or async iterable from fn and the result streams will be merged (flattened) into the returned stream.

Parameters

fn

(data, options?) => any

a function to map over every chunk in the stream. May be async. May be a stream or generator.

options?

ArrayOptions

Returns

Readable

a stream flat-mapped with the function fn.

Since

v17.5.0

Implementation of

dL.IMessageReadStream.flatMap

Inherited from

Readable.flatMap


forEach()

forEach(fn, options?): Promise<void>

Defined in: node_modules/@types/node/stream.d.ts:492

This method allows iterating a stream. For each chunk in the stream the fn function will be called. If the fn function returns a promise - that promise will be awaited.

This method is different from for await...of loops in that it can optionally process chunks concurrently. In addition, a forEach iteration can only be stopped by having passed a signal option and aborting the related AbortController while for await...of can be stopped with break or return. In either case the stream will be destroyed.

This method is different from listening to the 'data' event in that it uses the readable event in the underlying machinary and can limit the number of concurrent fn calls.

Parameters

fn

(data, options?) => void | Promise<void>

a function to call on each chunk of the stream. Async or not.

options?

ArrayOptions

Returns

Promise<void>

a promise for when the stream has finished.

Since

v17.5.0

Implementation of

dL.IMessageReadStream.forEach

Inherited from

Readable.forEach


getMaxListeners()

getMaxListeners(): number

Defined in: node_modules/@types/node/events.d.ts:819

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

Returns

number

Since

v1.0.0

Implementation of

dL.IMessageReadStream.getMaxListeners

Inherited from

Readable.getMaxListeners


isPaused()

isPaused(): boolean

Defined in: node_modules/@types/node/stream.d.ts:326

The readable.isPaused() method returns the current operating state of the Readable. This is used primarily by the mechanism that underlies the readable.pipe() method. In most typical cases, there will be no reason to use this method directly.

js
const readable = new stream.Readable();

readable.isPaused(); // === false
readable.pause();
readable.isPaused(); // === true
readable.resume();
readable.isPaused(); // === false

Returns

boolean

Since

v0.11.14

Implementation of

dL.IMessageReadStream.isPaused

Inherited from

Readable.isPaused


iterator()

iterator(options?): AsyncIterator<any>

Defined in: node_modules/@types/node/stream.d.ts:456

The iterator created by this method gives users the option to cancel the destruction of the stream if the for await...of loop is exited by return, break, or throw, or if the iterator should destroy the stream if the stream emitted an error during iteration.

Parameters

options?
destroyOnReturn?

boolean

When set to false, calling return on the async iterator, or exiting a for await...of iteration using a break, return, or throw will not destroy the stream. Default: true.

Returns

AsyncIterator<any>

Since

v16.3.0

Implementation of

dL.IMessageReadStream.iterator

Inherited from

Readable.iterator


listenerCount()

listenerCount<K>(eventName, listener?): number

Defined in: node_modules/@types/node/events.d.ts:913

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

K

Parameters

eventName

The name of the event being listened for

string | symbol

listener?

Function

The event handler function

Returns

number

Since

v3.2.0

Implementation of

dL.IMessageReadStream.listenerCount

Inherited from

Readable.listenerCount


listeners()

listeners<K>(eventName): Function[]

Defined in: node_modules/@types/node/events.d.ts:832

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

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

Type Parameters

K

K

Parameters

eventName

string | symbol

Returns

Function[]

Since

v0.1.26

Implementation of

dL.IMessageReadStream.listeners

Inherited from

Readable.listeners


map()

map(fn, options?): Readable

Defined in: node_modules/@types/node/stream.d.ts:464

This method allows mapping over the stream. The fn function will be called for every chunk in the stream. If the fn function returns a promise - that promise will be awaited before being passed to the result stream.

Parameters

fn

(data, options?) => any

a function to map over every chunk in the stream. Async or not.

options?

ArrayOptions

Returns

Readable

a stream mapped with the function fn.

Since

v17.4.0, v16.14.0

Implementation of

dL.IMessageReadStream.map

Inherited from

Readable.map


off()

off<K>(eventName, listener): this

Defined in: node_modules/@types/node/events.d.ts:792

Alias for emitter.removeListener().

Type Parameters

K

K

Parameters

eventName

string | symbol

listener

(...args) => void

Returns

this

Since

v10.0.0

Implementation of

dL.IMessageReadStream.off

Inherited from

Readable.off


on()

Call Signature

on(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:656

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.

js
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.

js
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
Parameters
event

"close"

listener

() => void

The callback function

Returns

this

Since

v0.1.101

Implementation of

dL.IMessageReadStream.on

Inherited from

Readable.on

Call Signature

on(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:657

Parameters
event

"data"

listener

(chunk) => void

Returns

this

Implementation of

dL.IMessageReadStream.on

Inherited from

Readable.on

Call Signature

on(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:658

Parameters
event

"end"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.on

Inherited from

Readable.on

Call Signature

on(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:659

Parameters
event

"error"

listener

(err) => void

Returns

this

Implementation of

dL.IMessageReadStream.on

Inherited from

Readable.on

Call Signature

on(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:660

Parameters
event

"pause"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.on

Inherited from

Readable.on

Call Signature

on(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:661

Parameters
event

"readable"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.on

Inherited from

Readable.on

Call Signature

on(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:662

Parameters
event

"resume"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.on

Inherited from

Readable.on

Call Signature

on(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:663

Parameters
event

string | symbol

listener

(...args) => void

Returns

this

Implementation of

dL.IMessageReadStream.on

Inherited from

Readable.on


once()

Call Signature

once(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:664

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

js
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.

js
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
Parameters
event

"close"

listener

() => void

The callback function

Returns

this

Since

v0.3.0

Implementation of

dL.IMessageReadStream.once

Inherited from

Readable.once

Call Signature

once(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:665

Parameters
event

"data"

listener

(chunk) => void

Returns

this

Implementation of

dL.IMessageReadStream.once

Inherited from

Readable.once

Call Signature

once(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:666

Parameters
event

"end"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.once

Inherited from

Readable.once

Call Signature

once(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:667

Parameters
event

"error"

listener

(err) => void

Returns

this

Implementation of

dL.IMessageReadStream.once

Inherited from

Readable.once

Call Signature

once(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:668

Parameters
event

"pause"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.once

Inherited from

Readable.once

Call Signature

once(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:669

Parameters
event

"readable"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.once

Inherited from

Readable.once

Call Signature

once(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:670

Parameters
event

"resume"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.once

Inherited from

Readable.once

Call Signature

once(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:671

Parameters
event

string | symbol

listener

(...args) => void

Returns

this

Implementation of

dL.IMessageReadStream.once

Inherited from

Readable.once


pause()

pause(): this

Defined in: node_modules/@types/node/stream.d.ts:290

The readable.pause() method will cause a stream in flowing mode to stop emitting 'data' events, switching out of flowing mode. Any data that becomes available will remain in the internal buffer.

js
const readable = getReadableStreamSomehow();
readable.on('data', (chunk) => {
  console.log(`Received ${chunk.length} bytes of data.`);
  readable.pause();
  console.log('There will be no additional data for 1 second.');
  setTimeout(() => {
    console.log('Now data will start flowing again.');
    readable.resume();
  }, 1000);
});

The readable.pause() method has no effect if there is a 'readable' event listener.

Returns

this

Since

v0.9.4

Implementation of

dL.IMessageReadStream.pause

Inherited from

Readable.pause


pipe()

pipe<T>(destination, options?): T

Defined in: node_modules/@types/node/stream.d.ts:29

Type Parameters

T

T extends WritableStream

Parameters

destination

T

options?
end?

boolean

Returns

T

Implementation of

dL.IMessageReadStream.pipe

Inherited from

Readable.pipe


prependListener()

Call Signature

prependListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:672

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.

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

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

Parameters
event

"close"

listener

() => void

The callback function

Returns

this

Since

v6.0.0

Implementation of

dL.IMessageReadStream.prependListener

Inherited from

Readable.prependListener

Call Signature

prependListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:673

Parameters
event

"data"

listener

(chunk) => void

Returns

this

Implementation of

dL.IMessageReadStream.prependListener

Inherited from

Readable.prependListener

Call Signature

prependListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:674

Parameters
event

"end"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.prependListener

Inherited from

Readable.prependListener

Call Signature

prependListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:675

Parameters
event

"error"

listener

(err) => void

Returns

this

Implementation of

dL.IMessageReadStream.prependListener

Inherited from

Readable.prependListener

Call Signature

prependListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:676

Parameters
event

"pause"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.prependListener

Inherited from

Readable.prependListener

Call Signature

prependListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:677

Parameters
event

"readable"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.prependListener

Inherited from

Readable.prependListener

Call Signature

prependListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:678

Parameters
event

"resume"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.prependListener

Inherited from

Readable.prependListener

Call Signature

prependListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:679

Parameters
event

string | symbol

listener

(...args) => void

Returns

this

Implementation of

dL.IMessageReadStream.prependListener

Inherited from

Readable.prependListener


prependOnceListener()

Call Signature

prependOnceListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:680

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.

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

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

Parameters
event

"close"

listener

() => void

The callback function

Returns

this

Since

v6.0.0

Implementation of

dL.IMessageReadStream.prependOnceListener

Inherited from

Readable.prependOnceListener

Call Signature

prependOnceListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:681

Parameters
event

"data"

listener

(chunk) => void

Returns

this

Implementation of

dL.IMessageReadStream.prependOnceListener

Inherited from

Readable.prependOnceListener

Call Signature

prependOnceListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:682

Parameters
event

"end"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.prependOnceListener

Inherited from

Readable.prependOnceListener

Call Signature

prependOnceListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:683

Parameters
event

"error"

listener

(err) => void

Returns

this

Implementation of

dL.IMessageReadStream.prependOnceListener

Inherited from

Readable.prependOnceListener

Call Signature

prependOnceListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:684

Parameters
event

"pause"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.prependOnceListener

Inherited from

Readable.prependOnceListener

Call Signature

prependOnceListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:685

Parameters
event

"readable"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.prependOnceListener

Inherited from

Readable.prependOnceListener

Call Signature

prependOnceListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:686

Parameters
event

"resume"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.prependOnceListener

Inherited from

Readable.prependOnceListener

Call Signature

prependOnceListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:687

Parameters
event

string | symbol

listener

(...args) => void

Returns

this

Implementation of

dL.IMessageReadStream.prependOnceListener

Inherited from

Readable.prependOnceListener


push()

push(chunk, encoding?): boolean

Defined in: node_modules/@types/node/stream.d.ts:446

Parameters

chunk

any

encoding?

BufferEncoding

Returns

boolean

Implementation of

dL.IMessageReadStream.push

Inherited from

Readable.push


rawListeners()

rawListeners<K>(eventName): Function[]

Defined in: node_modules/@types/node/events.d.ts:863

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

js
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

K

Parameters

eventName

string | symbol

Returns

Function[]

Since

v9.4.0

Implementation of

dL.IMessageReadStream.rawListeners

Inherited from

Readable.rawListeners


read()

read(size?): any

Defined in: node_modules/@types/node/stream.d.ts:243

The readable.read() method reads data out of the internal buffer and returns it. If no data is available to be read, null is returned. By default, the data is returned as a Buffer object unless an encoding has been specified using the readable.setEncoding() method or the stream is operating in object mode.

The optional size argument specifies a specific number of bytes to read. If size bytes are not available to be read, null will be returned unless the stream has ended, in which case all of the data remaining in the internal buffer will be returned.

If the size argument is not specified, all of the data contained in the internal buffer will be returned.

The size argument must be less than or equal to 1 GiB.

The readable.read() method should only be called on Readable streams operating in paused mode. In flowing mode, readable.read() is called automatically until the internal buffer is fully drained.

js
const readable = getReadableStreamSomehow();

// 'readable' may be triggered multiple times as data is buffered in
readable.on('readable', () => {
  let chunk;
  console.log('Stream is readable (new data received in buffer)');
  // Use a loop to make sure we read all currently available data
  while (null !== (chunk = readable.read())) {
    console.log(`Read ${chunk.length} bytes of data...`);
  }
});

// 'end' will be triggered once when there is no more data available
readable.on('end', () => {
  console.log('Reached end of stream.');
});

Each call to readable.read() returns a chunk of data, or null. The chunks are not concatenated. A while loop is necessary to consume all data currently in the buffer. When reading a large file .read() may return null, having consumed all buffered content so far, but there is still more data to come not yet buffered. In this case a new 'readable' event will be emitted when there is more data in the buffer. Finally the 'end' event will be emitted when there is no more data to come.

Therefore to read a file's whole contents from a readable, it is necessary to collect chunks across multiple 'readable' events:

js
const chunks = [];

readable.on('readable', () => {
  let chunk;
  while (null !== (chunk = readable.read())) {
    chunks.push(chunk);
  }
});

readable.on('end', () => {
  const content = chunks.join('');
});

A Readable stream in object mode will always return a single item from a call to readable.read(size), regardless of the value of the size argument.

If the readable.read() method returns a chunk of data, a 'data' event will also be emitted.

Calling read after the 'end' event has been emitted will return null. No runtime error will be raised.

Parameters

size?

number

Optional argument to specify how much data to read.

Returns

any

Since

v0.9.4

Implementation of

dL.IMessageReadStream.read

Inherited from

Readable.read


reduce()

Call Signature

reduce<T>(fn, initial?, options?): Promise<T>

Defined in: node_modules/@types/node/stream.d.ts:595

This method calls fn on each chunk of the stream in order, passing it the result from the calculation on the previous element. It returns a promise for the final value of the reduction.

If no initial value is supplied the first chunk of the stream is used as the initial value. If the stream is empty, the promise is rejected with a TypeError with the ERR_INVALID_ARGS code property.

The reducer function iterates the stream element-by-element which means that there is no concurrency parameter or parallelism. To perform a reduce concurrently, you can extract the async function to readable.map method.

Type Parameters
T

T = any

Parameters
fn

(previous, data, options?) => T

a reducer function to call over every chunk in the stream. Async or not.

initial?

undefined

the initial value to use in the reduction.

options?

Pick<ArrayOptions, "signal">

Returns

Promise<T>

a promise for the final value of the reduction.

Since

v17.5.0

Implementation of

dL.IMessageReadStream.reduce

Inherited from

Readable.reduce

Call Signature

reduce<T>(fn, initial, options?): Promise<T>

Defined in: node_modules/@types/node/stream.d.ts:600

This method calls fn on each chunk of the stream in order, passing it the result from the calculation on the previous element. It returns a promise for the final value of the reduction.

If no initial value is supplied the first chunk of the stream is used as the initial value. If the stream is empty, the promise is rejected with a TypeError with the ERR_INVALID_ARGS code property.

The reducer function iterates the stream element-by-element which means that there is no concurrency parameter or parallelism. To perform a reduce concurrently, you can extract the async function to readable.map method.

Type Parameters
T

T = any

Parameters
fn

(previous, data, options?) => T

a reducer function to call over every chunk in the stream. Async or not.

initial

T

the initial value to use in the reduction.

options?

Pick<ArrayOptions, "signal">

Returns

Promise<T>

a promise for the final value of the reduction.

Since

v17.5.0

Implementation of

dL.IMessageReadStream.reduce

Inherited from

Readable.reduce


removeAllListeners()

removeAllListeners(eventName?): this

Defined in: node_modules/@types/node/events.d.ts:803

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

Implementation of

dL.IMessageReadStream.removeAllListeners

Inherited from

Readable.removeAllListeners


removeListener()

Call Signature

removeListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:688

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

js
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.

js
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:

js
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.

Parameters
event

"close"

listener

() => void

Returns

this

Since

v0.1.26

Implementation of

dL.IMessageReadStream.removeListener

Inherited from

Readable.removeListener

Call Signature

removeListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:689

Parameters
event

"data"

listener

(chunk) => void

Returns

this

Implementation of

dL.IMessageReadStream.removeListener

Inherited from

Readable.removeListener

Call Signature

removeListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:690

Parameters
event

"end"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.removeListener

Inherited from

Readable.removeListener

Call Signature

removeListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:691

Parameters
event

"error"

listener

(err) => void

Returns

this

Implementation of

dL.IMessageReadStream.removeListener

Inherited from

Readable.removeListener

Call Signature

removeListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:692

Parameters
event

"pause"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.removeListener

Inherited from

Readable.removeListener

Call Signature

removeListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:693

Parameters
event

"readable"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.removeListener

Inherited from

Readable.removeListener

Call Signature

removeListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:694

Parameters
event

"resume"

listener

() => void

Returns

this

Implementation of

dL.IMessageReadStream.removeListener

Inherited from

Readable.removeListener

Call Signature

removeListener(event, listener): this

Defined in: node_modules/@types/node/stream.d.ts:695

Parameters
event

string | symbol

listener

(...args) => void

Returns

this

Implementation of

dL.IMessageReadStream.removeListener

Inherited from

Readable.removeListener


resume()

resume(): this

Defined in: node_modules/@types/node/stream.d.ts:309

The readable.resume() method causes an explicitly paused Readable stream to resume emitting 'data' events, switching the stream into flowing mode.

The readable.resume() method can be used to fully consume the data from a stream without actually processing any of that data:

js
getReadableStreamSomehow()
  .resume()
  .on('end', () => {
    console.log('Reached the end, but did not read anything.');
  });

The readable.resume() method has no effect if there is a 'readable' event listener.

Returns

this

Since

v0.9.4

Implementation of

dL.IMessageReadStream.resume

Inherited from

Readable.resume


setEncoding()

setEncoding(encoding): this

Defined in: node_modules/@types/node/stream.d.ts:268

The readable.setEncoding() method sets the character encoding for data read from the Readable stream.

By default, no encoding is assigned and stream data will be returned as Buffer objects. Setting an encoding causes the stream data to be returned as strings of the specified encoding rather than as Buffer objects. For instance, calling readable.setEncoding('utf8') will cause the output data to be interpreted as UTF-8 data, and passed as strings. Calling readable.setEncoding('hex') will cause the data to be encoded in hexadecimal string format.

The Readable stream will properly handle multi-byte characters delivered through the stream that would otherwise become improperly decoded if simply pulled from the stream as Buffer objects.

js
const readable = getReadableStreamSomehow();
readable.setEncoding('utf8');
readable.on('data', (chunk) => {
  assert.equal(typeof chunk, 'string');
  console.log('Got %d characters of string data:', chunk.length);
});

Parameters

encoding

BufferEncoding

The encoding to use.

Returns

this

Since

v0.9.4

Implementation of

dL.IMessageReadStream.setEncoding

Inherited from

Readable.setEncoding


setMaxListeners()

setMaxListeners(n): this

Defined in: node_modules/@types/node/events.d.ts:813

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

Implementation of

dL.IMessageReadStream.setMaxListeners

Inherited from

Readable.setMaxListeners


some()

some(fn, options?): Promise<boolean>

Defined in: node_modules/@types/node/stream.d.ts:514

This method is similar to Array.prototype.some and calls fn on each chunk in the stream until the awaited return value is true (or any truthy value). Once an fn call on a chunk awaited return value is truthy, the stream is destroyed and the promise is fulfilled with true. If none of the fn calls on the chunks return a truthy value, the promise is fulfilled with false.

Parameters

fn

(data, options?) => boolean | Promise<boolean>

a function to call on each chunk of the stream. Async or not.

options?

ArrayOptions

Returns

Promise<boolean>

a promise evaluating to true if fn returned a truthy value for at least one of the chunks.

Since

v17.5.0

Implementation of

dL.IMessageReadStream.some

Inherited from

Readable.some


take()

take(limit, options?): Readable

Defined in: node_modules/@types/node/stream.d.ts:573

This method returns a new stream with the first limit chunks.

Parameters

limit

number

the number of chunks to take from the readable.

options?

Pick<ArrayOptions, "signal">

Returns

Readable

a stream with limit chunks taken.

Since

v17.5.0

Implementation of

dL.IMessageReadStream.take

Inherited from

Readable.take


toArray()

toArray(options?): Promise<any[]>

Defined in: node_modules/@types/node/stream.d.ts:504

This method allows easily obtaining the contents of a stream.

As this method reads the entire stream into memory, it negates the benefits of streams. It's intended for interoperability and convenience, not as the primary way to consume streams.

Parameters

options?

Pick<ArrayOptions, "signal">

Returns

Promise<any[]>

a promise containing an array with the contents of the stream.

Since

v17.5.0

Implementation of

dL.IMessageReadStream.toArray

Inherited from

Readable.toArray


toBuffer()

toBuffer(): Promise<Buffer<ArrayBufferLike>>

Defined in: src/lib/MessageReadStream.ts:60

Read all data in this message as a single buffer.

Returns

Promise<Buffer<ArrayBufferLike>>

Implementation of

IMessageReadStream.toBuffer


toBufferArray()

toBufferArray(): Promise<Buffer<ArrayBufferLike>[]>

Defined in: src/lib/MessageReadStream.ts:79

Read all data in this message as an array of buffers, without copying data.

Returns

Promise<Buffer<ArrayBufferLike>[]>

Implementation of

IMessageReadStream.toBufferArray


toString()

toString(): Promise<string>

Defined in: src/lib/MessageReadStream.ts:39

Returns a string representation of an object.

Returns

Promise<string>

Implementation of

IMessageReadStream.toString


unpipe()

unpipe(destination?): this

Defined in: node_modules/@types/node/stream.d.ts:353

The readable.unpipe() method detaches a Writable stream previously attached using the pipe method.

If the destination is not specified, then all pipes are detached.

If the destination is specified, but no pipe is set up for it, then the method does nothing.

js
import fs from 'node:fs';
const readable = getReadableStreamSomehow();
const writable = fs.createWriteStream('file.txt');
// All the data from readable goes into 'file.txt',
// but only for the first second.
readable.pipe(writable);
setTimeout(() => {
  console.log('Stop writing to file.txt.');
  readable.unpipe(writable);
  console.log('Manually close the file stream.');
  writable.end();
}, 1000);

Parameters

destination?

WritableStream

Optional specific stream to unpipe

Returns

this

Since

v0.9.4

Implementation of

dL.IMessageReadStream.unpipe

Inherited from

Readable.unpipe


unshift()

unshift(chunk, encoding?): void

Defined in: node_modules/@types/node/stream.d.ts:419

Passing chunk as null signals the end of the stream (EOF) and behaves the same as readable.push(null), after which no more data can be written. The EOF signal is put at the end of the buffer and any buffered data will still be flushed.

The readable.unshift() method pushes a chunk of data back into the internal buffer. This is useful in certain situations where a stream is being consumed by code that needs to "un-consume" some amount of data that it has optimistically pulled out of the source, so that the data can be passed on to some other party.

The stream.unshift(chunk) method cannot be called after the 'end' event has been emitted or a runtime error will be thrown.

Developers using stream.unshift() often should consider switching to use of a Transform stream instead. See the API for stream implementers section for more information.

js
// Pull off a header delimited by \n\n.
// Use unshift() if we get too much.
// Call the callback with (error, header, stream).
import { StringDecoder } from 'node:string_decoder';
function parseHeader(stream, callback) {
  stream.on('error', callback);
  stream.on('readable', onReadable);
  const decoder = new StringDecoder('utf8');
  let header = '';
  function onReadable() {
    let chunk;
    while (null !== (chunk = stream.read())) {
      const str = decoder.write(chunk);
      if (str.includes('\n\n')) {
        // Found the header boundary.
        const split = str.split(/\n\n/);
        header += split.shift();
        const remaining = split.join('\n\n');
        const buf = Buffer.from(remaining, 'utf8');
        stream.removeListener('error', callback);
        // Remove the 'readable' listener before unshifting.
        stream.removeListener('readable', onReadable);
        if (buf.length)
          stream.unshift(buf);
        // Now the body of the message can be read from the stream.
        callback(null, header, stream);
        return;
      }
      // Still reading the header.
      header += str;
    }
  }
}

Unlike push, stream.unshift(chunk) will not end the reading process by resetting the internal reading state of the stream. This can cause unexpected results if readable.unshift() is called during a read (i.e. from within a _read implementation on a custom stream). Following the call to readable.unshift() with an immediate push will reset the reading state appropriately, however it is best to simply avoid calling readable.unshift() while in the process of performing a read.

Parameters

chunk

any

Chunk of data to unshift onto the read queue. For streams not operating in object mode, chunk must be a {string}, {Buffer}, {TypedArray}, {DataView} or null. For object mode streams, chunk may be any JavaScript value.

encoding?

BufferEncoding

Encoding of string chunks. Must be a valid Buffer encoding, such as 'utf8' or 'ascii'.

Returns

void

Since

v0.9.11

Implementation of

dL.IMessageReadStream.unshift

Inherited from

Readable.unshift


wrap()

wrap(stream): this

Defined in: node_modules/@types/node/stream.d.ts:445

Prior to Node.js 0.10, streams did not implement the entire node:stream module API as it is currently defined. (See Compatibility for more information.)

When using an older Node.js library that emits 'data' events and has a pause method that is advisory only, the readable.wrap() method can be used to create a Readable stream that uses the old stream as its data source.

It will rarely be necessary to use readable.wrap() but the method has been provided as a convenience for interacting with older Node.js applications and libraries.

js
import { OldReader } from './old-api-module.js';
import { Readable } from 'node:stream';
const oreader = new OldReader();
const myReader = new Readable().wrap(oreader);

myReader.on('readable', () => {
  myReader.read(); // etc.
});

Parameters

stream

ReadableStream

An "old style" readable stream

Returns

this

Since

v0.9.4

Implementation of

dL.IMessageReadStream.wrap

Inherited from

Readable.wrap


addAbortListener()

static addAbortListener(signal, resource): Disposable

Defined in: node_modules/@types/node/events.d.ts:403

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.

js
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

(event) => void

Returns

Disposable

Disposable that removes the abort listener.

Since

v20.5.0

Inherited from

Readable.addAbortListener


from()

static from(iterable, options?): Readable

Defined in: node_modules/@types/node/stream.d.ts:75

A utility method for creating Readable Streams out of iterators.

Parameters

iterable

Object implementing the Symbol.asyncIterator or Symbol.iterator iterable protocol. Emits an 'error' event if a null value is passed.

Iterable<any, any, any> | AsyncIterable<any, any, any>

options?

ReadableOptions<Readable>

Options provided to new stream.Readable([options]). By default, Readable.from() will set options.objectMode to true, unless this is explicitly opted out by setting options.objectMode to false.

Returns

Readable

Since

v12.3.0, v10.17.0

Inherited from

Readable.from


fromWeb()

static fromWeb(readableStream, options?): Readable

Defined in: node_modules/@types/node/stream.d.ts:80

A utility method for creating a Readable from a web ReadableStream.

Parameters

readableStream

ReadableStream

options?

Pick<ReadableOptions<Readable>, "signal" | "encoding" | "highWaterMark" | "objectMode">

Returns

Readable

Since

v17.0.0

Inherited from

Readable.fromWeb


getEventListeners()

static getEventListeners(emitter, name): Function[]

Defined in: node_modules/@types/node/events.d.ts:325

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.

js
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

Readable.getEventListeners


getMaxListeners()

static getMaxListeners(emitter): number

Defined in: node_modules/@types/node/events.d.ts:354

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.

js
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

Readable.getMaxListeners


isDisturbed()

static isDisturbed(stream): boolean

Defined in: node_modules/@types/node/stream.d.ts:98

Returns whether the stream has been read from or cancelled.

Parameters

stream

Readable | ReadableStream

Returns

boolean

Since

v16.8.0

Inherited from

Readable.isDisturbed


listenerCount()

static listenerCount(emitter, eventName): number

Defined in: node_modules/@types/node/events.d.ts:297

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

js
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

The emitter to query

eventName

The event name

string | symbol

Returns

number

Since

v0.9.12

Deprecated

Since v3.2.0 - Use listenerCount instead.

Inherited from

Readable.listenerCount


on()

Call Signature

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

Defined in: node_modules/@types/node/events.d.ts:270

js
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:

js
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:

js
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

eventName

string | symbol

options?

StaticEventEmitterIteratorOptions

Returns

AsyncIterator<any[]>

An AsyncIterator that iterates eventName events emitted by the emitter

Since

v13.6.0, v12.16.0

Inherited from

Readable.on

Call Signature

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

Defined in: node_modules/@types/node/events.d.ts:275

js
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:

js
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:

js
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

EventTarget

eventName

string

options?

StaticEventEmitterIteratorOptions

Returns

AsyncIterator<any[]>

An AsyncIterator that iterates eventName events emitted by the emitter

Since

v13.6.0, v12.16.0

Inherited from

Readable.on


once()

Call Signature

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

Defined in: node_modules/@types/node/events.d.ts:184

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.

js
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:

js
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:

js
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

eventName

string | symbol

options?

StaticEventEmitterOptions

Returns

Promise<any[]>

Since

v11.13.0, v10.16.0

Inherited from

Readable.once

Call Signature

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

Defined in: node_modules/@types/node/events.d.ts:189

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.

js
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:

js
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:

js
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

EventTarget

eventName

string

options?

StaticEventEmitterOptions

Returns

Promise<any[]>

Since

v11.13.0, v10.16.0

Inherited from

Readable.once


setMaxListeners()

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

Defined in: node_modules/@types/node/events.d.ts:369

js
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>)[]

Zero or more {EventTarget} or {EventEmitter} instances. If none are specified, n is set as the default max for all newly created {EventTarget} and {EventEmitter} objects.

Returns

void

Since

v15.4.0

Inherited from

Readable.setMaxListeners


toWeb()

static toWeb(streamReadable, options?): ReadableStream

Defined in: node_modules/@types/node/stream.d.ts:88

A utility method for creating a web ReadableStream from a Readable.

Parameters

streamReadable

Readable

options?
strategy?

QueuingStrategy<any>

Returns

ReadableStream

Since

v17.0.0

Inherited from

Readable.toWeb