GunzipConditional

@webda/core • Readme | API

Class: GunzipConditional

Gunzip a stream only if it is gzipped

Extends

Transform

Constructors

new GunzipConditional()

new GunzipConditional(): GunzipConditional

Returns

GunzipConditional

Overrides

Transform.constructor

Source

packages/core/src/utils/serializers.ts:73

Properties

allowHalfOpen

allowHalfOpen: boolean

If false then the stream will automatically end the writable side when the readable side ends. Set initially by the allowHalfOpen constructor option, which defaults to false.

This can be changed manually to change the half-open behavior of an existingDuplex stream instance, but must be changed before the 'end' event is emitted.

Since

v0.9.4

Inherited from

Transform.allowHalfOpen

Source

packages/core/node_modules/@types/node/stream.d.ts:873

closed

readonly closed: boolean

Inherited from

Transform.closed

Source

packages/core/node_modules/@types/node/stream.d.ts:862

destination

destination: WritableStream

Source

packages/core/src/utils/serializers.ts:70

destroyed

destroyed: boolean

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

Since

v8.0.0

Inherited from

Transform.destroyed

Source

packages/core/node_modules/@types/node/stream.d.ts:129

errored

readonly errored: Error

Inherited from

Transform.errored

Source

packages/core/node_modules/@types/node/stream.d.ts:863

first

first: boolean = true

Source

packages/core/src/utils/serializers.ts:68

readable

readable: boolean

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

Since

v11.4.0

Inherited from

Transform.readable

Source

packages/core/node_modules/@types/node/stream.d.ts:85

readableAborted

Experimental

readonly readableAborted: boolean

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

Since

v16.8.0

Inherited from

Transform.readableAborted

Source

packages/core/node_modules/@types/node/stream.d.ts:79

readableDidRead

Experimental

readonly readableDidRead: boolean

Returns whether 'data' has been emitted.

Since

v16.7.0, v14.18.0

Inherited from

Transform.readableDidRead

Source

packages/core/node_modules/@types/node/stream.d.ts:91

readableEncoding

readonly readableEncoding: BufferEncoding

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

Since

v12.7.0

Inherited from

Transform.readableEncoding

Source

packages/core/node_modules/@types/node/stream.d.ts:96

readableEnded

readonly readableEnded: boolean

Becomes true when 'end' event is emitted.

Since

v12.9.0

Inherited from

Transform.readableEnded

Source

packages/core/node_modules/@types/node/stream.d.ts:101

readableFlowing

readonly readableFlowing: boolean

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

Since

v9.4.0

Inherited from

Transform.readableFlowing

Source

packages/core/node_modules/@types/node/stream.d.ts:107

readableHighWaterMark

readonly readableHighWaterMark: number

Returns the value of highWaterMark passed when creating this Readable.

Since

v9.3.0

Inherited from

Transform.readableHighWaterMark

Source

packages/core/node_modules/@types/node/stream.d.ts:112

readableLength

readonly readableLength: number

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

Inherited from

Transform.readableLength

Source

packages/core/node_modules/@types/node/stream.d.ts:119

readableObjectMode

readonly readableObjectMode: boolean

Getter for the property objectMode of a given Readable stream.

Since

v12.3.0

Inherited from

Transform.readableObjectMode

Source

packages/core/node_modules/@types/node/stream.d.ts:124

source

source: any

Source

packages/core/src/utils/serializers.ts:71

writable

readonly writable: boolean

Inherited from

Transform.writable

Source

packages/core/node_modules/@types/node/stream.d.ts:854

writableCorked

readonly writableCorked: number

Inherited from

Transform.writableCorked

Source

packages/core/node_modules/@types/node/stream.d.ts:860

writableEnded

readonly writableEnded: boolean

Inherited from

Transform.writableEnded

Source

packages/core/node_modules/@types/node/stream.d.ts:855

writableFinished

readonly writableFinished: boolean

Inherited from

Transform.writableFinished

Source

packages/core/node_modules/@types/node/stream.d.ts:856

writableHighWaterMark

readonly writableHighWaterMark: number

Inherited from

Transform.writableHighWaterMark

Source

packages/core/node_modules/@types/node/stream.d.ts:857

writableLength

readonly writableLength: number

Inherited from

Transform.writableLength

Source

packages/core/node_modules/@types/node/stream.d.ts:858

writableNeedDrain

readonly writableNeedDrain: boolean

Inherited from

Transform.writableNeedDrain

Source

packages/core/node_modules/@types/node/stream.d.ts:861

writableObjectMode

readonly writableObjectMode: boolean

Inherited from

Transform.writableObjectMode

Source

packages/core/node_modules/@types/node/stream.d.ts:859

zlib

zlib: Transform

Source

packages/core/src/utils/serializers.ts:69

captureRejectionSymbol

static readonly captureRejectionSymbol: typeof captureRejectionSymbol

Inherited from

Transform.captureRejectionSymbol

Source

packages/core/node_modules/@types/node/events.d.ts:328

captureRejections

static captureRejections: boolean

Sets or gets the default captureRejection value for all emitters.

Inherited from

Transform.captureRejections

Source

packages/core/node_modules/@types/node/events.d.ts:333

defaultMaxListeners

static defaultMaxListeners: number

Inherited from

Transform.defaultMaxListeners

Source

packages/core/node_modules/@types/node/events.d.ts:334

errorMonitor

static readonly errorMonitor: typeof errorMonitor

This symbol shall be used to install a listener for only monitoring 'error' events. Listeners installed using this symbol are called before the regular 'error' listeners are called.

Installing a listener using this symbol does not change the behavior once an 'error' event is emitted, therefore the process will still crash if no regular 'error' listener is installed.

Inherited from

Transform.errorMonitor

Source

packages/core/node_modules/@types/node/events.d.ts:327

Methods

`[asyncIterator]`()

[asyncIterator](): AsyncIterableIterator<any, any, any>

Returns

AsyncIterableIterator<any, any, any>

Inherited from

Transform.[asyncIterator]

Source

packages/core/node_modules/@types/node/stream.d.ts:503

_construct()?

optional _construct(callback): void

Parameters

• callback: (error?) => void

Returns

void

Inherited from

Transform._construct

Source

packages/core/node_modules/@types/node/stream.d.ts:141

_destroy()

_destroy(error, callback): void

Parameters

• error: Error

• callback: (error) => void

Returns

void

Inherited from

Transform._destroy

Source

packages/core/node_modules/@types/node/stream.d.ts:905

_final()

_final(callback): void

Parameters

• callback: (error?) => void

Returns

void

Inherited from

Transform._final

Source

packages/core/node_modules/@types/node/stream.d.ts:906

_flush()

_flush(callback): void

Parameters

• callback: TransformCallback

Returns

void

Inherited from

Transform._flush

Source

packages/core/node_modules/@types/node/stream.d.ts:948

_read()

_read(size): void

Parameters

• size: number

Returns

void

Inherited from

Transform._read

Source

packages/core/node_modules/@types/node/stream.d.ts:142

_transform()

_transform(chunk, encoding, callback): void

Parameters

• chunk: any

• encoding: BufferEncoding

• callback: TransformCallback

Returns

void

Overrides

Transform._transform

Source

packages/core/src/utils/serializers.ts:85

_write()

_write(chunk, encoding, callback): void

Parameters

• chunk: any

• encoding: BufferEncoding

• callback: (error?) => void

Returns

void

Inherited from

Transform._write

Source

packages/core/node_modules/@types/node/stream.d.ts:897

_writev()?

optional _writev(chunks, callback): void

Parameters

• chunks: Object[]

• callback: (error?) => void

Returns

void

Inherited from

Transform._writev

Source

packages/core/node_modules/@types/node/stream.d.ts:898

addListener()

addListener(event, listener)

addListener(event, listener): this

Event emitter The defined events on documents including:

close
data
end
error
pause
readable
resume

Parameters

• event: "close"

• listener: () => void

Returns

this

Inherited from

Transform.addListener

Source

packages/core/node_modules/@types/node/stream.d.ts:447

addListener(event, listener)

addListener(event, listener): this

Parameters

• event: "data"

• listener: (chunk) => void

Returns

this

Inherited from

Transform.addListener

Source

packages/core/node_modules/@types/node/stream.d.ts:448

addListener(event, listener)

addListener(event, listener): this

Parameters

• event: "end"

• listener: () => void

Returns

this

Inherited from

Transform.addListener

Source

packages/core/node_modules/@types/node/stream.d.ts:449

addListener(event, listener)

addListener(event, listener): this

Parameters

• event: "error"

• listener: (err) => void

Returns

this

Inherited from

Transform.addListener

Source

packages/core/node_modules/@types/node/stream.d.ts:450

addListener(event, listener)

addListener(event, listener): this

Parameters

• event: "pause"

• listener: () => void

Returns

this

Inherited from

Transform.addListener

Source

packages/core/node_modules/@types/node/stream.d.ts:451

addListener(event, listener)

addListener(event, listener): this

Parameters

• event: "readable"

• listener: () => void

Returns

this

Inherited from

Transform.addListener

Source

packages/core/node_modules/@types/node/stream.d.ts:452

addListener(event, listener)

addListener(event, listener): this

Parameters

• event: "resume"

• listener: () => void

Returns

this

Inherited from

Transform.addListener

Source

packages/core/node_modules/@types/node/stream.d.ts:453

addListener(event, listener)

addListener(event, listener): this

Parameters

• event: string | symbol

• listener: (...args) => void

Returns

this

Inherited from

Transform.addListener

Source

packages/core/node_modules/@types/node/stream.d.ts:454

cork()

cork(): void

Returns

void

Inherited from

Transform.cork

Source

packages/core/node_modules/@types/node/stream.d.ts:913

destroy()

destroy(error?): this

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

Inherited from

Transform.destroy

Since

v8.0.0

Source

packages/core/node_modules/@types/node/stream.d.ts:435

emit()

emit(event)

emit(event): boolean

Parameters

• event: "close"

Returns

boolean

Inherited from

Transform.emit

Source

packages/core/node_modules/@types/node/stream.d.ts:455

emit(event, chunk)

emit(event, chunk): boolean

Parameters

• event: "data"

• chunk: any

Returns

boolean

Inherited from

Transform.emit

Source

packages/core/node_modules/@types/node/stream.d.ts:456

emit(event)

emit(event): boolean

Parameters

• event: "end"

Returns

boolean

Inherited from

Transform.emit

Source

packages/core/node_modules/@types/node/stream.d.ts:457

emit(event, err)

emit(event, err): boolean

Parameters

• event: "error"

• err: Error

Returns

boolean

Inherited from

Transform.emit

Source

packages/core/node_modules/@types/node/stream.d.ts:458

emit(event)

emit(event): boolean

Parameters

• event: "pause"

Returns

boolean

Inherited from

Transform.emit

Source

packages/core/node_modules/@types/node/stream.d.ts:459

emit(event)

emit(event): boolean

Parameters

• event: "readable"

Returns

boolean

Inherited from

Transform.emit

Source

packages/core/node_modules/@types/node/stream.d.ts:460

emit(event)

emit(event): boolean

Parameters

• event: "resume"

Returns

boolean

Inherited from

Transform.emit

Source

packages/core/node_modules/@types/node/stream.d.ts:461

emit(event, args)

emit(event, ...args): boolean

Parameters

• event: string | symbol

• ...args: any[]

Returns

boolean

Inherited from

Transform.emit

Source

packages/core/node_modules/@types/node/stream.d.ts:462

end()

end(cb)

end(cb?): this

Parameters

• cb?: () => void

Returns

this

Inherited from

Transform.end

Source

packages/core/node_modules/@types/node/stream.d.ts:910

end(chunk, cb)

end(chunk, cb?): this

Parameters

• chunk: any

• cb?: () => void

Returns

this

Inherited from

Transform.end

Source

packages/core/node_modules/@types/node/stream.d.ts:911

end(chunk, encoding, cb)

end(chunk, encoding?, cb?): this

Parameters

• chunk: any

• encoding?: BufferEncoding

• cb?: () => void

Returns

this

Inherited from

Transform.end

Source

packages/core/node_modules/@types/node/stream.d.ts:912

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.

const EventEmitter = require('events');
const myEE = new EventEmitter();
myEE.on('foo', () => {});
myEE.on('bar', () => {});

const sym = Symbol('symbol');
myEE.on(sym, () => {});

console.log(myEE.eventNames());
// Prints: [ 'foo', 'bar', Symbol(symbol) ]

Returns

(string | symbol)[]

Inherited from

Transform.eventNames

Since

v6.0.0

Source

packages/core/node_modules/@types/node/events.d.ts:669

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

Inherited from

Transform.getMaxListeners

Since

v1.0.0

Source

packages/core/node_modules/@types/node/events.d.ts:526

isPaused()

isPaused(): boolean

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

const readable = new stream.Readable();

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

Returns

boolean

Inherited from

Transform.isPaused

Since

v0.11.14

Source

packages/core/node_modules/@types/node/stream.d.ts:302

listenerCount()

listenerCount(eventName): number

Returns the number of listeners listening to the event named eventName.

Parameters

• eventName: string | symbol

The name of the event being listened for

Returns

number

Inherited from

Transform.listenerCount

Since

v3.2.0

Source

packages/core/node_modules/@types/node/events.d.ts:616

listeners()

listeners(eventName): Function[]

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

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

Parameters

• eventName: string | symbol

Returns

Function[]

Inherited from

Transform.listeners

Since

v0.1.26

Source

packages/core/node_modules/@types/node/events.d.ts:539

off()

off(eventName, listener): this

Alias for emitter.removeListener().

Parameters

• eventName: string | symbol

• listener: (...args) => void

Returns

this

Inherited from

Transform.off

Since

v10.0.0

Source

packages/core/node_modules/@types/node/events.d.ts:499

on()

on(event, listener)

on(event, listener): this

Parameters

• event: "close"

• listener: () => void

Returns

this

Inherited from

Transform.on

Source

packages/core/node_modules/@types/node/stream.d.ts:463

on(event, listener)

on(event, listener): this

Parameters

• event: "data"

• listener: (chunk) => void

Returns

this

Inherited from

Transform.on

Source

packages/core/node_modules/@types/node/stream.d.ts:464

on(event, listener)

on(event, listener): this

Parameters

• event: "end"

• listener: () => void

Returns

this

Inherited from

Transform.on

Source

packages/core/node_modules/@types/node/stream.d.ts:465

on(event, listener)

on(event, listener): this

Parameters

• event: "error"

• listener: (err) => void

Returns

this

Inherited from

Transform.on

Source

packages/core/node_modules/@types/node/stream.d.ts:466

on(event, listener)

on(event, listener): this

Parameters

• event: "pause"

• listener: () => void

Returns

this

Inherited from

Transform.on

Source

packages/core/node_modules/@types/node/stream.d.ts:467

on(event, listener)

on(event, listener): this

Parameters

• event: "readable"

• listener: () => void

Returns

this

Inherited from

Transform.on

Source

packages/core/node_modules/@types/node/stream.d.ts:468

on(event, listener)

on(event, listener): this

Parameters

• event: "resume"

• listener: () => void

Returns

this

Inherited from

Transform.on

Source

packages/core/node_modules/@types/node/stream.d.ts:469

on(event, listener)

on(event, listener): this

Parameters

• event: string | symbol

• listener: (...args) => void

Returns

this

Inherited from

Transform.on

Source

packages/core/node_modules/@types/node/stream.d.ts:470

once()

once(event, listener)

once(event, listener): this

Parameters

• event: "close"

• listener: () => void

Returns

this

Inherited from

Transform.once

Source

packages/core/node_modules/@types/node/stream.d.ts:471

once(event, listener)

once(event, listener): this

Parameters

• event: "data"

• listener: (chunk) => void

Returns

this

Inherited from

Transform.once

Source

packages/core/node_modules/@types/node/stream.d.ts:472

once(event, listener)

once(event, listener): this

Parameters

• event: "end"

• listener: () => void

Returns

this

Inherited from

Transform.once

Source

packages/core/node_modules/@types/node/stream.d.ts:473

once(event, listener)

once(event, listener): this

Parameters

• event: "error"

• listener: (err) => void

Returns

this

Inherited from

Transform.once

Source

packages/core/node_modules/@types/node/stream.d.ts:474

once(event, listener)

once(event, listener): this

Parameters

• event: "pause"

• listener: () => void

Returns

this

Inherited from

Transform.once

Source

packages/core/node_modules/@types/node/stream.d.ts:475

once(event, listener)

once(event, listener): this

Parameters

• event: "readable"

• listener: () => void

Returns

this

Inherited from

Transform.once

Source

packages/core/node_modules/@types/node/stream.d.ts:476

once(event, listener)

once(event, listener): this

Parameters

• event: "resume"

• listener: () => void

Returns

this

Inherited from

Transform.once

Source

packages/core/node_modules/@types/node/stream.d.ts:477

once(event, listener)

once(event, listener): this

Parameters

• event: string | symbol

• listener: (...args) => void

Returns

this

Inherited from

Transform.once

Source

packages/core/node_modules/@types/node/stream.d.ts:478

pause()

pause(): this

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.

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

Inherited from

Transform.pause

Since

v0.9.4

Source

packages/core/node_modules/@types/node/stream.d.ts:266

pipe()

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

Type parameters

• T extends WritableStream

Parameters

• destination: T

• options?: Object

• options.end?: boolean

Returns

T

Overrides

Transform.pipe

Source

packages/core/src/utils/serializers.ts:80

prependListener()

prependListener(event, listener)

prependListener(event, listener): this

Parameters

• event: "close"

• listener: () => void

Returns

this

Inherited from

Transform.prependListener

Source

packages/core/node_modules/@types/node/stream.d.ts:479

prependListener(event, listener)

prependListener(event, listener): this

Parameters

• event: "data"

• listener: (chunk) => void

Returns

this

Inherited from

Transform.prependListener

Source

packages/core/node_modules/@types/node/stream.d.ts:480

prependListener(event, listener)

prependListener(event, listener): this

Parameters

• event: "end"

• listener: () => void

Returns

this

Inherited from

Transform.prependListener

Source

packages/core/node_modules/@types/node/stream.d.ts:481

prependListener(event, listener)

prependListener(event, listener): this

Parameters

• event: "error"

• listener: (err) => void

Returns

this

Inherited from

Transform.prependListener

Source

packages/core/node_modules/@types/node/stream.d.ts:482

prependListener(event, listener)

prependListener(event, listener): this

Parameters

• event: "pause"

• listener: () => void

Returns

this

Inherited from

Transform.prependListener

Source

packages/core/node_modules/@types/node/stream.d.ts:483

prependListener(event, listener)

prependListener(event, listener): this

Parameters

• event: "readable"

• listener: () => void

Returns

this

Inherited from

Transform.prependListener

Source

packages/core/node_modules/@types/node/stream.d.ts:484

prependListener(event, listener)

prependListener(event, listener): this

Parameters

• event: "resume"

• listener: () => void

Returns

this

Inherited from

Transform.prependListener

Source

packages/core/node_modules/@types/node/stream.d.ts:485

prependListener(event, listener)

prependListener(event, listener): this

Parameters

• event: string | symbol

• listener: (...args) => void

Returns

this

Inherited from

Transform.prependListener

Source

packages/core/node_modules/@types/node/stream.d.ts:486

prependOnceListener()

prependOnceListener(event, listener)

prependOnceListener(event, listener): this

Parameters

• event: "close"

• listener: () => void

Returns

this

Inherited from

Transform.prependOnceListener

Source

packages/core/node_modules/@types/node/stream.d.ts:487

prependOnceListener(event, listener)

prependOnceListener(event, listener): this

Parameters

• event: "data"

• listener: (chunk) => void

Returns

this

Inherited from

Transform.prependOnceListener

Source

packages/core/node_modules/@types/node/stream.d.ts:488

prependOnceListener(event, listener)

prependOnceListener(event, listener): this

Parameters

• event: "end"

• listener: () => void

Returns

this

Inherited from

Transform.prependOnceListener

Source

packages/core/node_modules/@types/node/stream.d.ts:489

prependOnceListener(event, listener)

prependOnceListener(event, listener): this

Parameters

• event: "error"

• listener: (err) => void

Returns

this

Inherited from

Transform.prependOnceListener

Source

packages/core/node_modules/@types/node/stream.d.ts:490

prependOnceListener(event, listener)

prependOnceListener(event, listener): this

Parameters

• event: "pause"

• listener: () => void

Returns

this

Inherited from

Transform.prependOnceListener

Source

packages/core/node_modules/@types/node/stream.d.ts:491

prependOnceListener(event, listener)

prependOnceListener(event, listener): this

Parameters

• event: "readable"

• listener: () => void

Returns

this

Inherited from

Transform.prependOnceListener

Source

packages/core/node_modules/@types/node/stream.d.ts:492

prependOnceListener(event, listener)

prependOnceListener(event, listener): this

Parameters

• event: "resume"

• listener: () => void

Returns

this

Inherited from

Transform.prependOnceListener

Source

packages/core/node_modules/@types/node/stream.d.ts:493

prependOnceListener(event, listener)

prependOnceListener(event, listener): this

Parameters

• event: string | symbol

• listener: (...args) => void

Returns

this

Inherited from

Transform.prependOnceListener

Source

packages/core/node_modules/@types/node/stream.d.ts:494

push()

push(chunk, encoding?): boolean

Parameters

• chunk: any

• encoding?: BufferEncoding

Returns

boolean

Inherited from

Transform.push

Source

packages/core/node_modules/@types/node/stream.d.ts:422

rawListeners()

rawListeners(eventName): Function[]

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

const emitter = new EventEmitter();
emitter.once('log', () => console.log('log once'));

// Returns a new Array with a function `onceWrapper` which has a property
// `listener` which contains the original listener bound above
const listeners = emitter.rawListeners('log');
const logFnWrapper = listeners[0];

// Logs "log once" to the console and does not unbind the `once` event
logFnWrapper.listener();

// Logs "log once" to the console and removes the listener
logFnWrapper();

emitter.on('log', () => console.log('log persistently'));
// Will return a new Array with a single function bound by `.on()` above
const newListeners = emitter.rawListeners('log');

// Logs "log persistently" twice
newListeners[0]();
emitter.emit('log');

Parameters

• eventName: string | symbol

Returns

Function[]

Inherited from

Transform.rawListeners

Since

v9.4.0

Source

packages/core/node_modules/@types/node/events.d.ts:569

read()

read(size?): any

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. Ifsize 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.

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:

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 thesize 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

Inherited from

Transform.read

Since

v0.9.4

Source

packages/core/node_modules/@types/node/stream.d.ts:219

removeAllListeners()

removeAllListeners(event?): 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

• event?: string | symbol

Returns

this

Inherited from

Transform.removeAllListeners

Since

v0.1.26

Source

packages/core/node_modules/@types/node/events.d.ts:510

removeListener()

removeListener(event, listener)

removeListener(event, listener): this

Parameters

• event: "close"

• listener: () => void

Returns

this

Inherited from

Transform.removeListener

Source

packages/core/node_modules/@types/node/stream.d.ts:495

removeListener(event, listener)

removeListener(event, listener): this

Parameters

• event: "data"

• listener: (chunk) => void

Returns

this

Inherited from

Transform.removeListener

Source

packages/core/node_modules/@types/node/stream.d.ts:496

removeListener(event, listener)

removeListener(event, listener): this

Parameters

• event: "end"

• listener: () => void

Returns

this

Inherited from

Transform.removeListener

Source

packages/core/node_modules/@types/node/stream.d.ts:497

removeListener(event, listener)

removeListener(event, listener): this

Parameters

• event: "error"

• listener: (err) => void

Returns

this

Inherited from

Transform.removeListener

Source

packages/core/node_modules/@types/node/stream.d.ts:498

removeListener(event, listener)

removeListener(event, listener): this

Parameters

• event: "pause"

• listener: () => void

Returns

this

Inherited from

Transform.removeListener

Source

packages/core/node_modules/@types/node/stream.d.ts:499

removeListener(event, listener)

removeListener(event, listener): this

Parameters

• event: "readable"

• listener: () => void

Returns

this

Inherited from

Transform.removeListener

Source

packages/core/node_modules/@types/node/stream.d.ts:500

removeListener(event, listener)

removeListener(event, listener): this

Parameters

• event: "resume"

• listener: () => void

Returns

this

Inherited from

Transform.removeListener

Source

packages/core/node_modules/@types/node/stream.d.ts:501

removeListener(event, listener)

removeListener(event, listener): this

Parameters

• event: string | symbol

• listener: (...args) => void

Returns

this

Inherited from

Transform.removeListener

Source

packages/core/node_modules/@types/node/stream.d.ts:502

resume()

resume(): this

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:

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

Inherited from

Transform.resume

Since

v0.9.4

Source

packages/core/node_modules/@types/node/stream.d.ts:285

setDefaultEncoding()

setDefaultEncoding(encoding): this

Parameters

• encoding: BufferEncoding

Returns

this

Inherited from

Transform.setDefaultEncoding

Source

packages/core/node_modules/@types/node/stream.d.ts:909

setEncoding()

setEncoding(encoding): this

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 asBuffer objects. Setting an encoding causes the stream data to be returned as strings of the specified encoding rather than as Bufferobjects. For instance, calling readable.setEncoding('utf8') will cause the output data to be interpreted as UTF-8 data, and passed as strings. Callingreadable.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.

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

Inherited from

Transform.setEncoding

Since

v0.9.4

Source

packages/core/node_modules/@types/node/stream.d.ts:244

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 toInfinity (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

Inherited from

Transform.setMaxListeners

Since

v0.3.5

Source

packages/core/node_modules/@types/node/events.d.ts:520

uncork()

uncork(): void

Returns

void

Inherited from

Transform.uncork

Source

packages/core/node_modules/@types/node/stream.d.ts:914

unpipe()

unpipe(destination?): this

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.

const fs = require('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

Inherited from

Transform.unpipe

Since

v0.9.4

Source

packages/core/node_modules/@types/node/stream.d.ts:329

unshift()

unshift(chunk, encoding?): void

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.

// Pull off a header delimited by \n\n.
// Use unshift() if we get too much.
// Call the callback with (error, header, stream).
const { StringDecoder } = require('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, Uint8Array 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

Inherited from

Transform.unshift

Since

v0.9.11

Source

packages/core/node_modules/@types/node/stream.d.ts:395

wrap()

wrap(stream): this

Prior to Node.js 0.10, streams did not implement the entire 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, thereadable.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.

const { OldReader } = require('./old-api-module.js');
const { Readable } = require('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

Inherited from

Transform.wrap

Since

v0.9.4

Source

packages/core/node_modules/@types/node/stream.d.ts:421

write()

write(chunk, encoding, cb)

write(chunk, encoding?, cb?): boolean

Parameters

• chunk: any

• encoding?: BufferEncoding

• cb?: (error) => void

Returns

boolean

Inherited from

Transform.write

Source

packages/core/node_modules/@types/node/stream.d.ts:907

write(chunk, cb)

write(chunk, cb?): boolean

Parameters

• chunk: any

• cb?: (error) => void

Returns

boolean

Inherited from

Transform.write

Source

packages/core/node_modules/@types/node/stream.d.ts:908

from()

static from(src): Duplex

A utility method for creating duplex streams.

Stream converts writable stream into writable Duplex and readable stream to Duplex.
Blob converts into readable Duplex.
string converts into readable Duplex.
ArrayBuffer converts into readable Duplex.
AsyncIterable converts into a readable Duplex. Cannot yield null.
AsyncGeneratorFunction converts into a readable/writable transform Duplex. Must take a source AsyncIterable as first parameter. Cannot yield null.
AsyncFunction converts into a writable Duplex. Must return either null or undefined
Object ({ writable, readable }) converts readable and writable into Stream and then combines them into Duplex where the Duplex will write to the writable and read from the readable.
Promise converts into readable Duplex. Value null is ignored.

Parameters

Returns

Duplex

Inherited from

Transform.from

Since

v16.8.0

Source

packages/core/node_modules/@types/node/stream.d.ts:896

fromWeb()

Experimental

static fromWeb(readableStream, options?): Readable

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

Parameters

• readableStream: ReadableStream<any>

• options?: Pick<ReadableOptions, "encoding" | "highWaterMark" | "objectMode" | "signal">

Returns

Readable

Inherited from

Transform.fromWeb

Since

v17.0.0

Source

packages/core/node_modules/@types/node/stream.d.ts:62

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.

const { getEventListeners, EventEmitter } = require('events');

{
  const ee = new EventEmitter();
  const listener = () => console.log('Events are fun');
  ee.on('foo', listener);
  getEventListeners(ee, 'foo'); // [listener]
}
{
  const et = new EventTarget();
  const listener = () => console.log('Events are fun');
  et.addEventListener('foo', listener);
  getEventListeners(et, 'foo'); // [listener]
}

Parameters

• emitter: EventEmitter | _DOMEventTarget

• name: string | symbol

Returns

Function[]

Inherited from

Transform.getEventListeners

Since

v15.2.0, v14.17.0

Source

packages/core/node_modules/@types/node/events.d.ts:299

isDisturbed()

static isDisturbed(stream): boolean

Returns whether the stream has been read from or cancelled.

Parameters

• stream: Readable | ReadableStream

Returns

boolean

Inherited from

Transform.isDisturbed

Since

v16.8.0

Source

packages/core/node_modules/@types/node/stream.d.ts:67

listenerCount()

static listenerCount(emitter, eventName): number

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

const { EventEmitter, listenerCount } = require('events');
const myEmitter = new EventEmitter();
myEmitter.on('event', () => {});
myEmitter.on('event', () => {});
console.log(listenerCount(myEmitter, 'event'));
// Prints: 2

Parameters

• emitter: EventEmitter

The emitter to query

• eventName: string | symbol

The event name

Returns

number

Inherited from

Transform.listenerCount

Since

v0.9.12

Deprecated

Since v3.2.0 - Use listenerCount instead.

Source

packages/core/node_modules/@types/node/events.d.ts:271

on()

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

const { on, EventEmitter } = require('events');

(async () => {
  const ee = new EventEmitter();

  // Emit later on
  process.nextTick(() => {
    ee.emit('foo', 'bar');
    ee.emit('foo', 42);
  });

  for await (const event of on(ee, 'foo')) {
    // The execution of this inner block is synchronous and it
    // processes one event at a time (even with await). Do not use
    // if concurrent execution is required.
    console.log(event); // prints ['bar'] [42]
  }
  // Unreachable here
})();

Returns an AsyncIterator that iterates eventName events. It will throw if the EventEmitter emits 'error'. It removes all listeners when exiting the loop. The value returned by each iteration is an array composed of the emitted event arguments.

An AbortSignal can be used to cancel waiting on events:

const { on, EventEmitter } = require('events');
const ac = new AbortController();

(async () => {
  const ee = new EventEmitter();

  // Emit later on
  process.nextTick(() => {
    ee.emit('foo', 'bar');
    ee.emit('foo', 42);
  });

  for await (const event of on(ee, 'foo', { signal: ac.signal })) {
    // The execution of this inner block is synchronous and it
    // processes one event at a time (even with await). Do not use
    // if concurrent execution is required.
    console.log(event); // prints ['bar'] [42]
  }
  // Unreachable here
})();

process.nextTick(() => ac.abort());

Parameters

• emitter: EventEmitter

• eventName: string

The name of the event being listened for

• options?: StaticEventEmitterOptions

Returns

AsyncIterableIterator<any, any, any>

that iterates eventName events emitted by the emitter

Inherited from

Transform.on

Since

v13.6.0, v12.16.0

Source

packages/core/node_modules/@types/node/events.d.ts:254

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.

const { once, EventEmitter } = require('events');

async function run() {
  const ee = new EventEmitter();

  process.nextTick(() => {
    ee.emit('myevent', 42);
  });

  const [value] = await once(ee, 'myevent');
  console.log(value);

  const err = new Error('kaboom');
  process.nextTick(() => {
    ee.emit('error', err);
  });

  try {
    await once(ee, 'myevent');
  } catch (err) {
    console.log('error happened', err);
  }
}

run();

The special handling of the 'error' event is only used when events.once()is used to wait for another event. If events.once() is used to wait for the 'error' event itself, then it is treated as any other kind of event without special handling:

const { EventEmitter, once } = require('events');

const ee = new EventEmitter();

once(ee, 'error')
  .then(([err]) => console.log('ok', err.message))
  .catch((err) => console.log('error', err.message));

ee.emit('error', new Error('boom'));

// Prints: ok boom

An AbortSignal can be used to cancel waiting for the event:

const { EventEmitter, once } = require('events');

const ee = new EventEmitter();
const ac = new AbortController();

async function foo(emitter, event, signal) {
  try {
    await once(emitter, event, { signal });
    console.log('event emitted!');
  } catch (error) {
    if (error.name === 'AbortError') {
      console.error('Waiting for the event was canceled!');
    } else {
      console.error('There was an error', error.message);
    }
  }
}

foo(ee, 'foo', ac.signal);
ac.abort(); // Abort waiting for the event
ee.emit('foo'); // Prints: Waiting for the event was canceled!

Parameters

• emitter: _NodeEventTarget

• eventName: string | symbol

• options?: StaticEventEmitterOptions

Returns

Promise<any[]>

Inherited from

Transform.once

Since

v11.13.0, v10.16.0

Source

packages/core/node_modules/@types/node/events.d.ts:194

once(emitter, eventName, options)

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

Parameters

• emitter: _DOMEventTarget

• eventName: string

• options?: StaticEventEmitterOptions

Returns

Promise<any[]>

Inherited from

Transform.once

Source

packages/core/node_modules/@types/node/events.d.ts:195

setMaxListeners()

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

const {
  setMaxListeners,
  EventEmitter
} = require('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?: (EventEmitter | _DOMEventTarget)[]

Returns

void

Inherited from

Transform.setMaxListeners

Since

v15.4.0

Source

packages/core/node_modules/@types/node/events.d.ts:317

toWeb()

Experimental

static toWeb(streamReadable): ReadableStream<any>

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

Parameters

• streamReadable: Readable

Returns

ReadableStream<any>

Inherited from

Transform.toWeb

Since

v17.0.0

Source

packages/core/node_modules/@types/node/stream.d.ts:73

Class: GunzipConditional

Extends​

Constructors​

new GunzipConditional()​

Returns​

Overrides​

Source​

Properties​

allowHalfOpen​

Since​

Inherited from​

Source​

closed​

Inherited from​

Source​

destination​

Source​

destroyed​

Since​

Inherited from​

Source​

errored​

Inherited from​

Source​

first​

Source​

readable​

Since​

Inherited from​

Source​

readableAborted​

Since​

Inherited from​

Source​

readableDidRead​

Since​

Inherited from​

Source​

readableEncoding​

Since​

Inherited from​

Source​

readableEnded​

Since​

Inherited from​

Source​

readableFlowing​

Since​

Inherited from​

Source​

readableHighWaterMark​

Since​

Inherited from​

Source​

readableLength​

Since​

Inherited from​

Source​

readableObjectMode​

Since​

Inherited from​

Source​

source​

Source​

writable​

Inherited from​

Source​

writableCorked​

Inherited from​

Source​

writableEnded​

Inherited from​

Source​

writableFinished​

Inherited from​

Source​

writableHighWaterMark​

Inherited from​

Source​

writableLength​

Extends

Constructors

new GunzipConditional()

Returns

Overrides

Source

Properties

allowHalfOpen

Since

Inherited from

Source

closed

Inherited from

Source

destination

Source

destroyed

Since

Inherited from

Source

errored

Inherited from

Source

first

Source

readable

Since

Inherited from

Source

readableAborted

Since

Inherited from

Source

readableDidRead

Since

Inherited from

Source

readableEncoding

Since

Inherited from

Source

readableEnded

Since

Inherited from

Source

readableFlowing

Since

Inherited from

Source

readableHighWaterMark

Since

Inherited from

Source

readableLength

Since

Inherited from

Source

readableObjectMode

Since

Inherited from

Source

source

Source

writable

Inherited from

Source

writableCorked

Inherited from

Source

writableEnded

Inherited from

Source

writableFinished

Inherited from

Source

writableHighWaterMark

Inherited from

Source

writableLength

Inherited from