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@ralphschuler.logger.Logger.<internal>.WriteStream

github-actions edited this page Nov 26, 2023 · 1 revision

Interface: WriteStream

Logger.<internal>.WriteStream

Represents the writable side of a TTY. In normal circumstances,process.stdout and process.stderr will be the onlytty.WriteStream instances created for a Node.js process and there should be no reason to create additional instances.

Since

v0.5.8

Hierarchy

Table of contents

Properties

Methods

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 true.

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

WriteStream.allowHalfOpen

Defined in

node_modules/@types/node/stream.d.ts:1068


autoSelectFamilyAttemptedAddresses

Readonly autoSelectFamilyAttemptedAddresses: string[]

This property is only present if the family autoselection algorithm is enabled in socket.connect(options) and it is an array of the addresses that have been attempted.

Each address is a string in the form of $IP:$PORT. If the connection was successful, then the last address is the one that the socket is currently connected to.

Since

v19.4.0

Inherited from

WriteStream.autoSelectFamilyAttemptedAddresses

Defined in

node_modules/@types/node/net.d.ts:251


bufferSize

Readonly bufferSize: number

This property shows the number of characters buffered for writing. The buffer may contain strings whose length after encoding is not yet known. So this number is only an approximation of the number of bytes in the buffer.

net.Socket has the property that socket.write() always works. This is to help users get up and running quickly. The computer cannot always keep up with the amount of data that is written to a socket. The network connection simply might be too slow. Node.js will internally queue up the data written to a socket and send it out over the wire when it is possible.

The consequence of this internal buffering is that memory may grow. Users who experience large or growing bufferSize should attempt to "throttle" the data flows in their program with socket.pause() and socket.resume().

Since

v0.3.8

Deprecated

Since v14.6.0 - Use writableLength instead.

Inherited from

WriteStream.bufferSize

Defined in

node_modules/@types/node/net.d.ts:269


bytesRead

Readonly bytesRead: number

The amount of received bytes.

Since

v0.5.3

Inherited from

WriteStream.bytesRead

Defined in

node_modules/@types/node/net.d.ts:274


bytesWritten

Readonly bytesWritten: number

The amount of bytes sent.

Since

v0.5.3

Inherited from

WriteStream.bytesWritten

Defined in

node_modules/@types/node/net.d.ts:279


closed

Readonly closed: boolean

Is true after 'close' has been emitted.

Since

v18.0.0

Inherited from

WriteStream.closed

Defined in

node_modules/@types/node/stream.d.ts:1057


columns

columns: number

A number specifying the number of columns the TTY currently has. This property is updated whenever the 'resize' event is emitted.

Since

v0.7.7

Inherited from

WriteStream.columns

Defined in

node_modules/@types/node/tty.d.ts:192


connecting

Readonly connecting: boolean

If true,socket.connect(options[, connectListener]) was called and has not yet finished. It will stay true until the socket becomes connected, then it is set to false and the 'connect' event is emitted. Note that the socket.connect(options[, connectListener]) callback is a listener for the 'connect' event.

Since

v6.1.0

Inherited from

WriteStream.connecting

Defined in

node_modules/@types/node/net.d.ts:287


destroyed

Readonly destroyed: boolean

See writable.destroyed for further details.

Inherited from

WriteStream.destroyed

Defined in

node_modules/@types/node/net.d.ts:297


errored

Readonly errored: null | Error

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

Since

v18.0.0

Inherited from

WriteStream.errored

Defined in

node_modules/@types/node/stream.d.ts:1058


isTTY

isTTY: boolean

A boolean that is always true.

Since

v0.5.8

Inherited from

WriteStream.isTTY

Defined in

node_modules/@types/node/tty.d.ts:203


localAddress

Optional Readonly localAddress: string

The string representation of the local IP address the remote client is connecting on. For example, in a server listening on '0.0.0.0', if a client connects on '192.168.1.1', the value of socket.localAddress would be'192.168.1.1'.

Since

v0.9.6

Inherited from

WriteStream.localAddress

Defined in

node_modules/@types/node/net.d.ts:304


localFamily

Optional Readonly localFamily: string

The string representation of the local IP family. 'IPv4' or 'IPv6'.

Since

v18.8.0, v16.18.0

Inherited from

WriteStream.localFamily

Defined in

node_modules/@types/node/net.d.ts:314


localPort

Optional Readonly localPort: number

The numeric representation of the local port. For example, 80 or 21.

Since

v0.9.6

Inherited from

WriteStream.localPort

Defined in

node_modules/@types/node/net.d.ts:309


pending

Readonly pending: boolean

This is true if the socket is not connected yet, either because .connect()has not yet been called or because it is still in the process of connecting (see socket.connecting).

Since

v11.2.0, v10.16.0

Inherited from

WriteStream.pending

Defined in

node_modules/@types/node/net.d.ts:293


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

WriteStream.readable

Defined in

node_modules/@types/node/stream.d.ts:70


readableAborted

Readonly readableAborted: boolean

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

Since

v16.8.0

Inherited from

WriteStream.readableAborted

Defined in

node_modules/@types/node/stream.d.ts:64


readableDidRead

Readonly readableDidRead: boolean

Returns whether 'data' has been emitted.

Since

v16.7.0, v14.18.0

Inherited from

WriteStream.readableDidRead

Defined in

node_modules/@types/node/stream.d.ts:76


readableEncoding

Readonly readableEncoding: null | 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

WriteStream.readableEncoding

Defined in

node_modules/@types/node/stream.d.ts:81


readableEnded

Readonly readableEnded: boolean

Becomes true when 'end' event is emitted.

Since

v12.9.0

Inherited from

WriteStream.readableEnded

Defined in

node_modules/@types/node/stream.d.ts:86


readableFlowing

Readonly readableFlowing: null | boolean

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

Since

v9.4.0

Inherited from

WriteStream.readableFlowing

Defined in

node_modules/@types/node/stream.d.ts:92


readableHighWaterMark

Readonly readableHighWaterMark: number

Returns the value of highWaterMark passed when creating this Readable.

Since

v9.3.0

Inherited from

WriteStream.readableHighWaterMark

Defined in

node_modules/@types/node/stream.d.ts:97


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

WriteStream.readableLength

Defined in

node_modules/@types/node/stream.d.ts:104


readableObjectMode

Readonly readableObjectMode: boolean

Getter for the property objectMode of a given Readable stream.

Since

v12.3.0

Inherited from

WriteStream.readableObjectMode

Defined in

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


readyState

Readonly readyState: SocketReadyState

This property represents the state of the connection as a string.

  • If the stream is connecting socket.readyState is opening.
  • If the stream is readable and writable, it is open.
  • If the stream is readable and not writable, it is readOnly.
  • If the stream is not readable and writable, it is writeOnly.

Since

v0.5.0

Inherited from

WriteStream.readyState

Defined in

node_modules/@types/node/net.d.ts:324


remoteAddress

Optional Readonly remoteAddress: string

The string representation of the remote IP address. For example,'74.125.127.100' or '2001:4860:a005::68'. Value may be undefined if the socket is destroyed (for example, if the client disconnected).

Since

v0.5.10

Inherited from

WriteStream.remoteAddress

Defined in

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


remoteFamily

Optional Readonly remoteFamily: string

The string representation of the remote IP family. 'IPv4' or 'IPv6'. Value may be undefined if the socket is destroyed (for example, if the client disconnected).

Since

v0.11.14

Inherited from

WriteStream.remoteFamily

Defined in

node_modules/@types/node/net.d.ts:336


remotePort

Optional Readonly remotePort: number

The numeric representation of the remote port. For example, 80 or 21. Value may be undefined if the socket is destroyed (for example, if the client disconnected).

Since

v0.5.10

Inherited from

WriteStream.remotePort

Defined in

node_modules/@types/node/net.d.ts:342


rows

rows: number

A number specifying the number of rows the TTY currently has. This property is updated whenever the 'resize' event is emitted.

Since

v0.7.7

Inherited from

WriteStream.rows

Defined in

node_modules/@types/node/tty.d.ts:198


timeout

Optional Readonly timeout: number

The socket timeout in milliseconds as set by socket.setTimeout(). It is undefined if a timeout has not been set.

Since

v10.7.0

Inherited from

WriteStream.timeout

Defined in

node_modules/@types/node/net.d.ts:348


writable

Readonly writable: boolean

Is true if it is safe to call writable.write(), which means the stream has not been destroyed, errored, or ended.

Since

v11.4.0

Inherited from

WriteStream.writable

Defined in

node_modules/@types/node/stream.d.ts:1049


writableCorked

Readonly writableCorked: number

Number of times writable.uncork() needs to be called in order to fully uncork the stream.

Since

v13.2.0, v12.16.0

Inherited from

WriteStream.writableCorked

Defined in

node_modules/@types/node/stream.d.ts:1055


writableEnded

Readonly writableEnded: boolean

Is true after writable.end() has been called. This property does not indicate whether the data has been flushed, for this use writable.writableFinished instead.

Since

v12.9.0

Inherited from

WriteStream.writableEnded

Defined in

node_modules/@types/node/stream.d.ts:1050


writableFinished

Readonly writableFinished: boolean

Is set to true immediately before the 'finish' event is emitted.

Since

v12.6.0

Inherited from

WriteStream.writableFinished

Defined in

node_modules/@types/node/stream.d.ts:1051


writableHighWaterMark

Readonly writableHighWaterMark: number

Return the value of highWaterMark passed when creating this Writable.

Since

v9.3.0

Inherited from

WriteStream.writableHighWaterMark

Defined in

node_modules/@types/node/stream.d.ts:1052


writableLength

Readonly writableLength: number

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

Since

v9.4.0

Inherited from

WriteStream.writableLength

Defined in

node_modules/@types/node/stream.d.ts:1053


writableNeedDrain

Readonly writableNeedDrain: boolean

Is true if the stream's buffer has been full and stream will emit 'drain'.

Since

v15.2.0, v14.17.0

Inherited from

WriteStream.writableNeedDrain

Defined in

node_modules/@types/node/stream.d.ts:1056


writableObjectMode

Readonly writableObjectMode: boolean

Getter for the property objectMode of a given Writable stream.

Since

v12.3.0

Inherited from

WriteStream.writableObjectMode

Defined in

node_modules/@types/node/stream.d.ts:1054

Methods

[asyncDispose]

[asyncDispose](): Promise<void>

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

Returns

Promise<void>

Since

v20.4.0

Inherited from

WriteStream.[asyncDispose]

Defined in

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


[asyncIterator]

[asyncIterator](): AsyncIterableIterator<any>

Returns

AsyncIterableIterator<any>

Inherited from

WriteStream.[asyncIterator]

Defined in

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


[captureRejectionSymbol]

[captureRejectionSymbol](error, event, ...args): void

Parameters

Name Type
error Error
event string
...args any[]

Returns

void

Inherited from

WriteStream.[captureRejectionSymbol]

Defined in

node_modules/@types/node/events.d.ts:112


_construct

_construct(callback): void

Parameters

Name Type
callback (error?: null | Error) => void

Returns

void

Inherited from

WriteStream._construct

Defined in

node_modules/@types/node/stream.d.ts:126


_destroy

_destroy(error, callback): void

Parameters

Name Type
error null | Error
callback (error: null | Error) => void

Returns

void

Inherited from

WriteStream._destroy

Defined in

node_modules/@types/node/stream.d.ts:1111


_final

_final(callback): void

Parameters

Name Type
callback (error?: null | Error) => void

Returns

void

Inherited from

WriteStream._final

Defined in

node_modules/@types/node/stream.d.ts:1112


_read

_read(size): void

Parameters

Name Type
size number

Returns

void

Inherited from

WriteStream._read

Defined in

node_modules/@types/node/stream.d.ts:127


_write

_write(chunk, encoding, callback): void

Parameters

Name Type
chunk any
encoding BufferEncoding
callback (error?: null | Error) => void

Returns

void

Inherited from

WriteStream._write

Defined in

node_modules/@types/node/stream.d.ts:1103


_writev

_writev(chunks, callback): void

Parameters

Name Type
chunks { chunk: any ; encoding: BufferEncoding }[]
callback (error?: null | Error) => void

Returns

void

Inherited from

WriteStream._writev

Defined in

node_modules/@types/node/stream.d.ts:1104


addListener

addListener(event, listener): WriteStream

events.EventEmitter

  1. close
  2. connect
  3. data
  4. drain
  5. end
  6. error
  7. lookup
  8. ready
  9. timeout

Parameters

Name Type
event string
listener (...args: any[]) => void

Returns

WriteStream

Inherited from

WriteStream.addListener

Defined in

node_modules/@types/node/tty.d.ts:85

addListener(event, listener): WriteStream

Parameters

Name Type
event "resize"
listener () => void

Returns

WriteStream

Inherited from

WriteStream.addListener

Defined in

node_modules/@types/node/tty.d.ts:86


address

address(): {} | AddressInfo

Returns the bound address, the address family name and port of the socket as reported by the operating system:{ port: 12346, family: 'IPv4', address: '127.0.0.1' }

Returns

{} | AddressInfo

Since

v0.1.90

Inherited from

WriteStream.address

Defined in

node_modules/@types/node/net.d.ts:228


asIndexedPairs

asIndexedPairs(options?): Readable

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

Name Type
options? Pick<ArrayOptions, "signal">

Returns

Readable

a stream of indexed pairs.

Since

v17.5.0

Inherited from

WriteStream.asIndexedPairs

Defined in

node_modules/@types/node/stream.d.ts:541


clearLine

clearLine(dir, callback?): boolean

writeStream.clearLine() clears the current line of this WriteStream in a direction identified by dir.

Parameters

Name Type Description
dir Direction -
callback? () => void Invoked once the operation completes.

Returns

boolean

false if the stream wishes for the calling code to wait for the 'drain' event to be emitted before continuing to write additional data; otherwise true.

Since

v0.7.7

Inherited from

WriteStream.clearLine

Defined in

node_modules/@types/node/tty.d.ts:104


clearScreenDown

clearScreenDown(callback?): boolean

writeStream.clearScreenDown() clears this WriteStream from the current cursor down.

Parameters

Name Type Description
callback? () => void Invoked once the operation completes.

Returns

boolean

false if the stream wishes for the calling code to wait for the 'drain' event to be emitted before continuing to write additional data; otherwise true.

Since

v0.7.7

Inherited from

WriteStream.clearScreenDown

Defined in

node_modules/@types/node/tty.d.ts:112


compose

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

Type parameters

Name Type
T extends ReadableStream

Parameters

Name Type
stream ComposeFnParam | T | Iterable<T> | AsyncIterable<T>
options? Object
options.signal AbortSignal

Returns

T

Inherited from

WriteStream.compose

Defined in

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


connect

connect(options, connectionListener?): WriteStream

Initiate a connection on a given socket.

Possible signatures:

  • socket.connect(options[, connectListener])
  • socket.connect(path[, connectListener]) for IPC connections.
  • socket.connect(port[, host][, connectListener]) for TCP connections.
  • Returns: net.Socket The socket itself.

This function is asynchronous. When the connection is established, the 'connect' event will be emitted. If there is a problem connecting, instead of a 'connect' event, an 'error' event will be emitted with the error passed to the 'error' listener. The last parameter connectListener, if supplied, will be added as a listener for the 'connect' event once.

This function should only be used for reconnecting a socket after'close' has been emitted or otherwise it may lead to undefined behavior.

Parameters

Name Type
options SocketConnectOpts
connectionListener? () => void

Returns

WriteStream

Inherited from

WriteStream.connect

Defined in

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

connect(port, host, connectionListener?): WriteStream

Parameters

Name Type
port number
host string
connectionListener? () => void

Returns

WriteStream

Inherited from

WriteStream.connect

Defined in

node_modules/@types/node/net.d.ts:137

connect(port, connectionListener?): WriteStream

Parameters

Name Type
port number
connectionListener? () => void

Returns

WriteStream

Inherited from

WriteStream.connect

Defined in

node_modules/@types/node/net.d.ts:138

connect(path, connectionListener?): WriteStream

Parameters

Name Type
path string
connectionListener? () => void

Returns

WriteStream

Inherited from

WriteStream.connect

Defined in

node_modules/@types/node/net.d.ts:139


cork

cork(): void

The writable.cork() method forces all written data to be buffered in memory. The buffered data will be flushed when either the uncork or end methods are called.

The primary intent of writable.cork() is to accommodate a situation in which several small chunks are written to the stream in rapid succession. Instead of immediately forwarding them to the underlying destination, writable.cork()buffers all the chunks until writable.uncork() is called, which will pass them all to writable._writev(), if present. This prevents a head-of-line blocking situation where data is being buffered while waiting for the first small chunk to be processed. However, use of writable.cork() without implementingwritable._writev() may have an adverse effect on throughput.

See also: writable.uncork(), writable._writev().

Returns

void

Since

v0.11.2

Inherited from

WriteStream.cork

Defined in

node_modules/@types/node/stream.d.ts:1119


cursorTo

cursorTo(x, y?, callback?): boolean

writeStream.cursorTo() moves this WriteStream's cursor to the specified position.

Parameters

Name Type Description
x number -
y? number -
callback? () => void Invoked once the operation completes.

Returns

boolean

false if the stream wishes for the calling code to wait for the 'drain' event to be emitted before continuing to write additional data; otherwise true.

Since

v0.7.7

Inherited from

WriteStream.cursorTo

Defined in

node_modules/@types/node/tty.d.ts:120

cursorTo(x, callback): boolean

Parameters

Name Type
x number
callback () => void

Returns

boolean

Inherited from

WriteStream.cursorTo

Defined in

node_modules/@types/node/tty.d.ts:121


destroy

destroy(error?): WriteStream

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

Name Type Description
error? Error Error which will be passed as payload in 'error' event

Returns

WriteStream

Since

v8.0.0

Inherited from

WriteStream.destroy

Defined in

node_modules/@types/node/stream.d.ts:578


destroySoon

destroySoon(): void

Destroys the socket after all data is written. If the finish event was already emitted the socket is destroyed immediately. If the socket is still writable it implicitly calls socket.end().

Returns

void

Since

v0.3.4

Inherited from

WriteStream.destroySoon

Defined in

node_modules/@types/node/net.d.ts:99


drop

drop(limit, options?): Readable

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

Parameters

Name Type Description
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

Inherited from

WriteStream.drop

Defined in

node_modules/@types/node/stream.d.ts:527


emit

emit(event, ...args): boolean

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

Returns true if the event had listeners, false otherwise.

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

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

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

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

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

Parameters

Name Type
event string | symbol
...args any[]

Returns

boolean

Since

v0.1.26

Inherited from

WriteStream.emit

Defined in

node_modules/@types/node/tty.d.ts:87

emit(event): boolean

Parameters

Name Type
event "resize"

Returns

boolean

Inherited from

WriteStream.emit

Defined in

node_modules/@types/node/tty.d.ts:88


end

end(callback?): WriteStream

Half-closes the socket. i.e., it sends a FIN packet. It is possible the server will still send some data.

See writable.end() for further details.

Parameters

Name Type Description
callback? () => void Optional callback for when the socket is finished.

Returns

WriteStream

The socket itself.

Since

v0.1.90

Inherited from

WriteStream.end

Defined in

node_modules/@types/node/net.d.ts:359

end(buffer, callback?): WriteStream

Parameters

Name Type
buffer string | Uint8Array
callback? () => void

Returns

WriteStream

Inherited from

WriteStream.end

Defined in

node_modules/@types/node/net.d.ts:360

end(str, encoding?, callback?): WriteStream

Parameters

Name Type
str string | Uint8Array
encoding? BufferEncoding
callback? () => void

Returns

WriteStream

Inherited from

WriteStream.end

Defined in

node_modules/@types/node/net.d.ts:361


eventNames

eventNames(): (string | symbol)[]

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

import { EventEmitter } from 'node:events';

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

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

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

Returns

(string | symbol)[]

Since

v6.0.0

Inherited from

WriteStream.eventNames

Defined in

node_modules/@types/node/events.d.ts:870


every

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

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

Name Type Description
fn (data: any, options?: Pick<ArrayOptions, "signal">) => 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

Inherited from

WriteStream.every

Defined in

node_modules/@types/node/stream.d.ts:506


filter

filter(fn, options?): Readable

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

Name Type Description
fn (data: any, options?: Pick<ArrayOptions, "signal">) => 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

Inherited from

WriteStream.filter

Defined in

node_modules/@types/node/stream.d.ts:434


find

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

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

Name
T

Parameters

Name Type Description
fn (data: any, options?: Pick<ArrayOptions, "signal">) => data is T a function to call on each chunk of the stream. Async or not.
options? ArrayOptions -

Returns

Promise<undefined | T>

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

Inherited from

WriteStream.find

Defined in

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

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

Parameters

Name Type
fn (data: any, options?: Pick<ArrayOptions, "signal">) => boolean | Promise<boolean>
options? ArrayOptions

Returns

Promise<any>

Inherited from

WriteStream.find

Defined in

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


flatMap

flatMap(fn, options?): Readable

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

Name Type Description
fn (data: any, options?: Pick<ArrayOptions, "signal">) => 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

Inherited from

WriteStream.flatMap

Defined in

node_modules/@types/node/stream.d.ts:520


forEach

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

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

Name Type Description
fn (data: any, options?: Pick<ArrayOptions, "signal">) => 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

Inherited from

WriteStream.forEach

Defined in

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


getColorDepth

getColorDepth(env?): number

Returns:

  • 1 for 2,
  • 4 for 16,
  • 8 for 256,
  • 24 for 16,777,216 colors supported.

Use this to determine what colors the terminal supports. Due to the nature of colors in terminals it is possible to either have false positives or false negatives. It depends on process information and the environment variables that may lie about what terminal is used. It is possible to pass in an env object to simulate the usage of a specific terminal. This can be useful to check how specific environment settings behave.

To enforce a specific color support, use one of the below environment settings.

  • 2 colors: FORCE_COLOR = 0 (Disables colors)
  • 16 colors: FORCE_COLOR = 1
  • 256 colors: FORCE_COLOR = 2
  • 16,777,216 colors: FORCE_COLOR = 3

Disabling color support is also possible by using the NO_COLOR andNODE_DISABLE_COLORS environment variables.

Parameters

Name Type Description
env? object An object containing the environment variables to check. This enables simulating the usage of a specific terminal.

Returns

number

Since

v9.9.0

Inherited from

WriteStream.getColorDepth

Defined in

node_modules/@types/node/tty.d.ts:156


getMaxListeners

getMaxListeners(): number

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

Returns

number

Since

v1.0.0

Inherited from

WriteStream.getMaxListeners

Defined in

node_modules/@types/node/events.d.ts:722


getWindowSize

getWindowSize(): [number, number]

writeStream.getWindowSize() returns the size of the TTY corresponding to this WriteStream. The array is of the type[numColumns, numRows] where numColumns and numRows represent the number of columns and rows in the corresponding TTY.

Returns

[number, number]

Since

v0.7.7

Inherited from

WriteStream.getWindowSize

Defined in

node_modules/@types/node/tty.d.ts:186


hasColors

hasColors(count?): boolean

Returns true if the writeStream supports at least as many colors as provided in count. Minimum support is 2 (black and white).

This has the same false positives and negatives as described in writeStream.getColorDepth().

process.stdout.hasColors();
// Returns true or false depending on if `stdout` supports at least 16 colors.
process.stdout.hasColors(256);
// Returns true or false depending on if `stdout` supports at least 256 colors.
process.stdout.hasColors({ TMUX: '1' });
// Returns true.
process.stdout.hasColors(2 ** 24, { TMUX: '1' });
// Returns false (the environment setting pretends to support 2 ** 8 colors).

Parameters

Name Type Description
count? number The number of colors that are requested (minimum 2).

Returns

boolean

Since

v11.13.0, v10.16.0

Inherited from

WriteStream.hasColors

Defined in

node_modules/@types/node/tty.d.ts:177

hasColors(env?): boolean

Parameters

Name Type
env? object

Returns

boolean

Inherited from

WriteStream.hasColors

Defined in

node_modules/@types/node/tty.d.ts:178

hasColors(count, env?): boolean

Parameters

Name Type
count number
env? object

Returns

boolean

Inherited from

WriteStream.hasColors

Defined in

node_modules/@types/node/tty.d.ts:179


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

Since

v0.11.14

Inherited from

WriteStream.isPaused

Defined in

node_modules/@types/node/stream.d.ts:287


iterator

iterator(options?): AsyncIterableIterator<any>

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

Name Type Description
options? Object -
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

AsyncIterableIterator<any>

Since

v16.3.0

Inherited from

WriteStream.iterator

Defined in

node_modules/@types/node/stream.d.ts:417


listenerCount

listenerCount(eventName, listener?): number

Returns the number of listeners listening for the event named eventName. If listener is provided, it will return how many times the listener is found in the list of the listeners of the event.

Parameters

Name Type Description
eventName string | symbol The name of the event being listened for
listener? Function The event handler function

Returns

number

Since

v3.2.0

Inherited from

WriteStream.listenerCount

Defined in

node_modules/@types/node/events.d.ts:816


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

Name Type
eventName string | symbol

Returns

Function[]

Since

v0.1.26

Inherited from

WriteStream.listeners

Defined in

node_modules/@types/node/events.d.ts:735


map

map(fn, options?): Readable

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

Name Type Description
fn (data: any, options?: Pick<ArrayOptions, "signal">) => 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

Inherited from

WriteStream.map

Defined in

node_modules/@types/node/stream.d.ts:425


moveCursor

moveCursor(dx, dy, callback?): boolean

writeStream.moveCursor() moves this WriteStream's cursor relative to its current position.

Parameters

Name Type Description
dx number -
dy number -
callback? () => void Invoked once the operation completes.

Returns

boolean

false if the stream wishes for the calling code to wait for the 'drain' event to be emitted before continuing to write additional data; otherwise true.

Since

v0.7.7

Inherited from

WriteStream.moveCursor

Defined in

node_modules/@types/node/tty.d.ts:129


off

off(eventName, listener): WriteStream

Alias for emitter.removeListener().

Parameters

Name Type
eventName string | symbol
listener (...args: any[]) => void

Returns

WriteStream

Since

v10.0.0

Inherited from

WriteStream.off

Defined in

node_modules/@types/node/events.d.ts:695


on

on(event, listener): WriteStream

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 eventNameand listener will result in the listener being added, and called, multiple times.

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

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

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

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

Parameters

Name Type Description
event string The name of the event.
listener (...args: any[]) => void The callback function

Returns

WriteStream

Since

v0.1.101

Inherited from

WriteStream.on

Defined in

node_modules/@types/node/tty.d.ts:89

on(event, listener): WriteStream

Parameters

Name Type
event "resize"
listener () => void

Returns

WriteStream

Inherited from

WriteStream.on

Defined in

node_modules/@types/node/tty.d.ts:90


once

once(event, listener): WriteStream

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

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

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

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

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

Parameters

Name Type Description
event string The name of the event.
listener (...args: any[]) => void The callback function

Returns

WriteStream

Since

v0.3.0

Inherited from

WriteStream.once

Defined in

node_modules/@types/node/tty.d.ts:91

once(event, listener): WriteStream

Parameters

Name Type
event "resize"
listener () => void

Returns

WriteStream

Inherited from

WriteStream.once

Defined in

node_modules/@types/node/tty.d.ts:92


pause

pause(): WriteStream

Pauses the reading of data. That is, 'data' events will not be emitted. Useful to throttle back an upload.

Returns

WriteStream

The socket itself.

Inherited from

WriteStream.pause

Defined in

node_modules/@types/node/net.d.ts:151


pipe

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

Type parameters

Name Type
T extends WritableStream

Parameters

Name Type
destination T
options? Object
options.end? boolean

Returns

T

Inherited from

WriteStream.pipe

Defined in

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


prependListener

prependListener(event, listener): WriteStream

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 eventNameand listener will result in the listener being added, and called, multiple times.

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

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

Parameters

Name Type Description
event string The name of the event.
listener (...args: any[]) => void The callback function

Returns

WriteStream

Since

v6.0.0

Inherited from

WriteStream.prependListener

Defined in

node_modules/@types/node/tty.d.ts:93

prependListener(event, listener): WriteStream

Parameters

Name Type
event "resize"
listener () => void

Returns

WriteStream

Inherited from

WriteStream.prependListener

Defined in

node_modules/@types/node/tty.d.ts:94


prependOnceListener

prependOnceListener(event, listener): WriteStream

Adds a one-timelistener function for the event named eventName to the beginning of the listeners array. The next time eventName is triggered, this listener is removed, and then invoked.

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

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

Parameters

Name Type Description
event string The name of the event.
listener (...args: any[]) => void The callback function

Returns

WriteStream

Since

v6.0.0

Inherited from

WriteStream.prependOnceListener

Defined in

node_modules/@types/node/tty.d.ts:95

prependOnceListener(event, listener): WriteStream

Parameters

Name Type
event "resize"
listener () => void

Returns

WriteStream

Inherited from

WriteStream.prependOnceListener

Defined in

node_modules/@types/node/tty.d.ts:96


push

push(chunk, encoding?): boolean

Parameters

Name Type
chunk any
encoding? BufferEncoding

Returns

boolean

Inherited from

WriteStream.push

Defined in

node_modules/@types/node/stream.d.ts:407


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()).

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');

Parameters

Name Type
eventName string | symbol

Returns

Function[]

Since

v9.4.0

Inherited from

WriteStream.rawListeners

Defined in

node_modules/@types/node/events.d.ts:766


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

Name Type Description
size? number Optional argument to specify how much data to read.

Returns

any

Since

v0.9.4

Inherited from

WriteStream.read

Defined in

node_modules/@types/node/stream.d.ts:204


reduce

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

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

Name Type
T any

Parameters

Name Type Description
fn (previous: any, data: any, options?: Pick<ArrayOptions, "signal">) => 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

Inherited from

WriteStream.reduce

Defined in

node_modules/@types/node/stream.d.ts:556

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

Type parameters

Name Type
T any

Parameters

Name Type
fn (previous: T, data: any, options?: Pick<ArrayOptions, "signal">) => T
initial T
options? Pick<ArrayOptions, "signal">

Returns

Promise<T>

Inherited from

WriteStream.reduce

Defined in

node_modules/@types/node/stream.d.ts:561


ref

ref(): WriteStream

Opposite of unref(), calling ref() on a previously unrefed socket will not let the program exit if it's the only socket left (the default behavior). If the socket is refed calling ref again will have no effect.

Returns

WriteStream

The socket itself.

Since

v0.9.1

Inherited from

WriteStream.ref

Defined in

node_modules/@types/node/net.d.ts:242


removeAllListeners

removeAllListeners(event?): WriteStream

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

Name Type
event? string | symbol

Returns

WriteStream

Since

v0.1.26

Inherited from

WriteStream.removeAllListeners

Defined in

node_modules/@types/node/events.d.ts:706


removeListener

removeListener(event, listener): WriteStream

Removes the specified listener from the listener array for the event namedeventName.

const callback = (stream) => {
  console.log('someone connected!');
};
server.on('connection', callback);
// ...
server.removeListener('connection', callback);

removeListener() will remove, at most, one instance of a listener from the listener array. If any single listener has been added multiple times to the listener array for the specified eventName, then removeListener() must be called multiple times to remove each instance.

Once an event is emitted, all listeners attached to it at the time of emitting are called in order. This implies that anyremoveListener() or removeAllListeners() calls after emitting and before the last listener finishes execution will not remove them fromemit() in progress. Subsequent events behave as expected.

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

const callbackA = () => {
  console.log('A');
  myEmitter.removeListener('event', callbackB);
};

const callbackB = () => {
  console.log('B');
};

myEmitter.on('event', callbackA);

myEmitter.on('event', callbackB);

// callbackA removes listener callbackB but it will still be called.
// Internal listener array at time of emit [callbackA, callbackB]
myEmitter.emit('event');
// Prints:
//   A
//   B

// callbackB is now removed.
// Internal listener array [callbackA]
myEmitter.emit('event');
// Prints:
//   A

Because listeners are managed using an internal array, calling this will change the position indices of any listener registered after the listener being removed. This will not impact the order in which listeners are called, but it means that any copies of the listener array as returned by the emitter.listeners() method will need to be recreated.

When a single function has been added as a handler multiple times for a single event (as in the example below), removeListener() will remove the most recently added instance. In the example the once('ping')listener is removed:

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

function pong() {
  console.log('pong');
}

ee.on('ping', pong);
ee.once('ping', pong);
ee.removeListener('ping', pong);

ee.emit('ping');
ee.emit('ping');

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

Parameters

Name Type
event "close"
listener () => void

Returns

WriteStream

Since

v0.1.26

Inherited from

WriteStream.removeListener

Defined in

node_modules/@types/node/stream.d.ts:1232

removeListener(event, listener): WriteStream

Parameters

Name Type
event "data"
listener (chunk: any) => void

Returns

WriteStream

Inherited from

WriteStream.removeListener

Defined in

node_modules/@types/node/stream.d.ts:1233

removeListener(event, listener): WriteStream

Parameters

Name Type
event "drain"
listener () => void

Returns

WriteStream

Inherited from

WriteStream.removeListener

Defined in

node_modules/@types/node/stream.d.ts:1234

removeListener(event, listener): WriteStream

Parameters

Name Type
event "end"
listener () => void

Returns

WriteStream

Inherited from

WriteStream.removeListener

Defined in

node_modules/@types/node/stream.d.ts:1235

removeListener(event, listener): WriteStream

Parameters

Name Type
event "error"
listener (err: Error) => void

Returns

WriteStream

Inherited from

WriteStream.removeListener

Defined in

node_modules/@types/node/stream.d.ts:1236

removeListener(event, listener): WriteStream

Parameters

Name Type
event "finish"
listener () => void

Returns

WriteStream

Inherited from

WriteStream.removeListener

Defined in

node_modules/@types/node/stream.d.ts:1237

removeListener(event, listener): WriteStream

Parameters

Name Type
event "pause"
listener () => void

Returns

WriteStream

Inherited from

WriteStream.removeListener

Defined in

node_modules/@types/node/stream.d.ts:1238

removeListener(event, listener): WriteStream

Parameters

Name Type
event "pipe"
listener (src: Readable) => void

Returns

WriteStream

Inherited from

WriteStream.removeListener

Defined in

node_modules/@types/node/stream.d.ts:1239

removeListener(event, listener): WriteStream

Parameters

Name Type
event "readable"
listener () => void

Returns

WriteStream

Inherited from

WriteStream.removeListener

Defined in

node_modules/@types/node/stream.d.ts:1240

removeListener(event, listener): WriteStream

Parameters

Name Type
event "resume"
listener () => void

Returns

WriteStream

Inherited from

WriteStream.removeListener

Defined in

node_modules/@types/node/stream.d.ts:1241

removeListener(event, listener): WriteStream

Parameters

Name Type
event "unpipe"
listener (src: Readable) => void

Returns

WriteStream

Inherited from

WriteStream.removeListener

Defined in

node_modules/@types/node/stream.d.ts:1242

removeListener(event, listener): WriteStream

Parameters

Name Type
event string | symbol
listener (...args: any[]) => void

Returns

WriteStream

Inherited from

WriteStream.removeListener

Defined in

node_modules/@types/node/stream.d.ts:1243


resetAndDestroy

resetAndDestroy(): WriteStream

Close the TCP connection by sending an RST packet and destroy the stream. If this TCP socket is in connecting status, it will send an RST packet and destroy this TCP socket once it is connected. Otherwise, it will call socket.destroy with an ERR_SOCKET_CLOSED Error. If this is not a TCP socket (for example, a pipe), calling this method will immediately throw an ERR_INVALID_HANDLE_TYPE Error.

Returns

WriteStream

Since

v18.3.0, v16.17.0

Inherited from

WriteStream.resetAndDestroy

Defined in

node_modules/@types/node/net.d.ts:159


resume

resume(): WriteStream

Resumes reading after a call to socket.pause().

Returns

WriteStream

The socket itself.

Inherited from

WriteStream.resume

Defined in

node_modules/@types/node/net.d.ts:164


setDefaultEncoding

setDefaultEncoding(encoding): WriteStream

The writable.setDefaultEncoding() method sets the default encoding for a Writable stream.

Parameters

Name Type Description
encoding BufferEncoding The new default encoding

Returns

WriteStream

Since

v0.11.15

Inherited from

WriteStream.setDefaultEncoding

Defined in

node_modules/@types/node/stream.d.ts:1115


setEncoding

setEncoding(encoding?): WriteStream

Set the encoding for the socket as a Readable Stream. See readable.setEncoding() for more information.

Parameters

Name Type
encoding? BufferEncoding

Returns

WriteStream

The socket itself.

Since

v0.1.90

Inherited from

WriteStream.setEncoding

Defined in

node_modules/@types/node/net.d.ts:145


setKeepAlive

setKeepAlive(enable?, initialDelay?): WriteStream

Enable/disable keep-alive functionality, and optionally set the initial delay before the first keepalive probe is sent on an idle socket.

Set initialDelay (in milliseconds) to set the delay between the last data packet received and the first keepalive probe. Setting 0 forinitialDelay will leave the value unchanged from the default (or previous) setting.

Enabling the keep-alive functionality will set the following socket options:

  • SO_KEEPALIVE=1
  • TCP_KEEPIDLE=initialDelay
  • TCP_KEEPCNT=10
  • TCP_KEEPINTVL=1

Parameters

Name Type
enable? boolean
initialDelay? number

Returns

WriteStream

The socket itself.

Since

v0.1.92

Inherited from

WriteStream.setKeepAlive

Defined in

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


setMaxListeners

setMaxListeners(n): WriteStream

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

Name Type
n number

Returns

WriteStream

Since

v0.3.5

Inherited from

WriteStream.setMaxListeners

Defined in

node_modules/@types/node/events.d.ts:716


setNoDelay

setNoDelay(noDelay?): WriteStream

Enable/disable the use of Nagle's algorithm.

When a TCP connection is created, it will have Nagle's algorithm enabled.

Nagle's algorithm delays data before it is sent via the network. It attempts to optimize throughput at the expense of latency.

Passing true for noDelay or not passing an argument will disable Nagle's algorithm for the socket. Passing false for noDelay will enable Nagle's algorithm.

Parameters

Name Type
noDelay? boolean

Returns

WriteStream

The socket itself.

Since

v0.1.90

Inherited from

WriteStream.setNoDelay

Defined in

node_modules/@types/node/net.d.ts:202


setTimeout

setTimeout(timeout, callback?): WriteStream

Sets the socket to timeout after timeout milliseconds of inactivity on the socket. By default net.Socket do not have a timeout.

When an idle timeout is triggered the socket will receive a 'timeout' event but the connection will not be severed. The user must manually call socket.end() or socket.destroy() to end the connection.

socket.setTimeout(3000);
socket.on('timeout', () => {
  console.log('socket timeout');
  socket.end();
});

If timeout is 0, then the existing idle timeout is disabled.

The optional callback parameter will be added as a one-time listener for the 'timeout' event.

Parameters

Name Type
timeout number
callback? () => void

Returns

WriteStream

The socket itself.

Since

v0.1.90

Inherited from

WriteStream.setTimeout

Defined in

node_modules/@types/node/net.d.ts:186


some

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

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

Name Type Description
fn (data: any, options?: Pick<ArrayOptions, "signal">) => 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

Inherited from

WriteStream.some

Defined in

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


take

take(limit, options?): Readable

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

Parameters

Name Type Description
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

Inherited from

WriteStream.take

Defined in

node_modules/@types/node/stream.d.ts:534


toArray

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

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

Name Type
options? Pick<ArrayOptions, "signal">

Returns

Promise<any[]>

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

Since

v17.5.0

Inherited from

WriteStream.toArray

Defined in

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


uncork

uncork(): void

The writable.uncork() method flushes all data buffered since cork was called.

When using writable.cork() and writable.uncork() to manage the buffering of writes to a stream, defer calls to writable.uncork() usingprocess.nextTick(). Doing so allows batching of allwritable.write() calls that occur within a given Node.js event loop phase.

stream.cork();
stream.write('some ');
stream.write('data ');
process.nextTick(() => stream.uncork());

If the writable.cork() method is called multiple times on a stream, the same number of calls to writable.uncork() must be called to flush the buffered data.

stream.cork();
stream.write('some ');
stream.cork();
stream.write('data ');
process.nextTick(() => {
  stream.uncork();
  // The data will not be flushed until uncork() is called a second time.
  stream.uncork();
});

See also: writable.cork().

Returns

void

Since

v0.11.2

Inherited from

WriteStream.uncork

Defined in

node_modules/@types/node/stream.d.ts:1120


unpipe

unpipe(destination?): WriteStream

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('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

Name Type Description
destination? WritableStream Optional specific stream to unpipe

Returns

WriteStream

Since

v0.9.4

Inherited from

WriteStream.unpipe

Defined in

node_modules/@types/node/stream.d.ts:314


unref

unref(): WriteStream

Calling unref() on a socket will allow the program to exit if this is the only active socket in the event system. If the socket is already unrefed callingunref() again will have no effect.

Returns

WriteStream

The socket itself.

Since

v0.9.1

Inherited from

WriteStream.unref

Defined in

node_modules/@types/node/net.d.ts:235


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('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

Name Type Description
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

Since

v0.9.11

Inherited from

WriteStream.unshift

Defined in

node_modules/@types/node/stream.d.ts:380


wrap

wrap(stream): WriteStream

Prior to Node.js 0.10, streams did not implement the entire node:streammodule 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('node:stream');
const oreader = new OldReader();
const myReader = new Readable().wrap(oreader);

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

Parameters

Name Type Description
stream ReadableStream An "old style" readable stream

Returns

WriteStream

Since

v0.9.4

Inherited from

WriteStream.wrap

Defined in

node_modules/@types/node/stream.d.ts:406


write

write(buffer, cb?): boolean

Sends data on the socket. The second parameter specifies the encoding in the case of a string. It defaults to UTF8 encoding.

Returns true if the entire data was flushed successfully to the kernel buffer. Returns false if all or part of the data was queued in user memory.'drain' will be emitted when the buffer is again free.

The optional callback parameter will be executed when the data is finally written out, which may not be immediately.

See Writable stream write() method for more information.

Parameters

Name Type
buffer string | Uint8Array
cb? (err?: Error) => void

Returns

boolean

Since

v0.1.90

Inherited from

WriteStream.write

Defined in

node_modules/@types/node/net.d.ts:115

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

Parameters

Name Type
str string | Uint8Array
encoding? BufferEncoding
cb? (err?: Error) => void

Returns

boolean

Inherited from

WriteStream.write

Defined in

node_modules/@types/node/net.d.ts:116

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