WorkerOutput

@webda/workout

---

Class: WorkerOutput

Defined in: packages/workout/src/core.ts:499

This class allow you to abstract the output for your program

You can send output, ask for input and depending if you are in terminal It will show progress in the terminal, or send it via WebSockets or store it in a DB or in a logfile

Extends

• EventEmitter

Constructors

Constructor

new WorkerOutput(options?): WorkerOutput

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:90

Parameters

options?

EventEmitterOptions

Returns

WorkerOutput

Inherited from

EventEmitter.constructor

Properties

addLogProducerLine

addLogProducerLine: boolean = false

Defined in: packages/workout/src/core.ts:515

When true, every log call records the caller's file/line/function in the message context

---

currentProgress?

optional currentProgress?: string

Defined in: packages/workout/src/core.ts:509

UID of the progress that receives increments by default

---

groups

groups: string[] = []

Defined in: packages/workout/src/core.ts:503

Stack of currently open group names

---

inputs

inputs: object = {}

Defined in: packages/workout/src/core.ts:513

Pending input requests awaiting a user response, keyed by UUID

Index Signature

[key: string]: WorkerInputEmitter

---

interactive

interactive: boolean = false

Defined in: packages/workout/src/core.ts:511

Whether the output is connected to an interactive session capable of receiving user input

---

progresses

progresses: object = {}

Defined in: packages/workout/src/core.ts:505

All active progress indicators keyed by UID

Index Signature

[key: string]: WorkerProgress

---

progressesStack

progressesStack: string[] = []

Defined in: packages/workout/src/core.ts:507

Ordered stack of active progress UIDs (last = current)

---

title?

optional title?: string

Defined in: packages/workout/src/core.ts:501

Optional title for the current output session

Methods

[captureRejectionSymbol]()?

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

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:123

The Symbol.for('nodejs.rejection') method is called in case a promise rejection happens when emitting an event and captureRejections is enabled on the emitter. It is possible to use events.captureRejectionSymbol in place of Symbol.for('nodejs.rejection').

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

class MyClass extends EventEmitter {
  constructor() {
    super({ captureRejections: true });
  }

  [captureRejectionSymbol](err, event, ...args) {
    console.log('rejection happened for', event, 'with', err, ...args);
    this.destroy(err);
  }

  destroy(err) {
    // Tear the resource down here.
  }
}

Parameters

error

Error

event

string | symbol

args

...any[]

Returns

void

Since

v13.4.0, v12.16.0

Inherited from

EventEmitter.[captureRejectionSymbol]

---

addListener()

addListener<E>(eventName, listener): this

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:128

Alias for emitter.on(eventName, listener).

Type Parameters

E

E extends string | symbol

Parameters

eventName

string | symbol

listener

(...args) => void

Returns

this

Since

v0.1.26

Inherited from

EventEmitter.addListener

---

closeGroup()

closeGroup(): void

Defined in: packages/workout/src/core.ts:632

Close a group of output

Returns

void

---

emit()

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

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:170

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

Returns true if the event had listeners, false otherwise.

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

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

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

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

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

Type Parameters

E

E extends string | symbol

Parameters

eventName

string | symbol

args

...any[]

Returns

boolean

Since

v0.1.26

Inherited from

EventEmitter.emit

---

emitMessage()

protected emitMessage(event, infos?): void

Defined in: packages/workout/src/core.ts:523

Send an event with default informations

Parameters

event

WorkerMessageType

the message type to emit

infos?

any = {}

additional data for the message

Returns

void

---

eventNames()

eventNames(): (string | symbol)[]

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:190

Returns an array listing the events for which the emitter has registered listeners.

import { EventEmitter } from 'node:events';

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

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

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

Returns

(string | symbol)[]

Since

v6.0.0

Inherited from

EventEmitter.eventNames

---

forwardEvent()

forwardEvent(rawEvent): void

Defined in: packages/workout/src/core.ts:785

Forward an event from another WorkerOutput (typically from a forked process)

Parameters

rawEvent

string

JSON string representation of a WorkerMessage

Returns

void

---

getBunyanLogger()

getBunyanLogger(): object

Defined in: packages/workout/src/core.ts:673

Get a Bunyan-compatible logger interface

Returns

object

An object with Bunyan-style logging methods (info, trace, warn, debug, error, fatal)

debug

debug: (...args) => boolean | void

Parameters

args

...any[]

Returns

boolean | void

error

error: (...args) => boolean | void

Parameters

args

...any[]

Returns

boolean | void

fatal

fatal: (...args) => boolean | void

Parameters

args

...any[]

Returns

boolean | void

info

info: (...args) => boolean | void

Parameters

args

...any[]

Returns

boolean | void

trace

trace: (...args) => boolean | void

Parameters

args

...any[]

Returns

boolean | void

warn

warn: (...args) => boolean | void

Parameters

args

...any[]

Returns

boolean | void

Example

const logger = output.getBunyanLogger();
logger.info("App started");
logger.error(err, "Request failed");

---

getMaxListeners()

getMaxListeners(): number

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:197

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

Returns

number

Since

v1.0.0

Inherited from

EventEmitter.getMaxListeners

---

incrementProgress()

incrementProgress(inc?, uid?, title?): void

Defined in: packages/workout/src/core.ts:584

Increment to add to progress

Parameters

inc?

number = 1

amount to increment

uid?

string = ...

progress identifier

title?

string

optional title to update

Returns

void

---

listenerCount()

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

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:206

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

Type Parameters

E

E extends string | symbol

Parameters

eventName

string | symbol

The name of the event being listened for

listener?

(...args) => void

The event handler function

Returns

number

Since

v3.2.0

Inherited from

EventEmitter.listenerCount

---

listeners()

listeners<E>(eventName): (...args) => void[]

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:222

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

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

Type Parameters

E

E extends string | symbol

Parameters

eventName

string | symbol

Returns

(...args) => void[]

Since

v0.1.26

Inherited from

EventEmitter.listeners

---

log()

log(level, ...args): void

Defined in: packages/workout/src/core.ts:655

Log something

Parameters

level

WorkerLogLevel

of log to use with filtering

args

...any[]

anything you want to log

Returns

void

---

logWithContext()

logWithContext(level, context, ...args): void

Defined in: packages/workout/src/core.ts:727

Log a message with additional context information

Parameters

level

WorkerLogLevel

The log level (ERROR, WARN, INFO, DEBUG, TRACE)

context

any

Context object to attach to the log (can include file, line, column, function, etc.)

args

...any[]

Message arguments to log

Returns

void

---

off()

off<E>(eventName, listener): this

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:227

Alias for emitter.removeListener().

Type Parameters

E

E extends string | symbol

Parameters

eventName

string | symbol

listener

(...args) => void

Returns

this

Since

v10.0.0

Inherited from

EventEmitter.off

---

on()

on<E>(eventName, listener): this

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:261

Adds the listener function to the end of the listeners array for the event named eventName. No checks are made to see if the listener has already been added. Multiple calls passing the same combination of eventName and listener will result in the listener being added, and called, multiple times.

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

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

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

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

Type Parameters

E

E extends string | symbol

Parameters

eventName

string | symbol

The name of the event.

listener

(...args) => void

The callback function

Returns

this

Since

v0.1.101

Inherited from

EventEmitter.on

---

once()

once<E>(eventName, listener): this

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:292

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

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

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

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

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

Type Parameters

E

E extends string | symbol

Parameters

eventName

string | symbol

The name of the event.

listener

(...args) => void

The callback function

Returns

this

Since

v0.3.0

Inherited from

EventEmitter.once

---

openGroup()

openGroup(name?): void

Defined in: packages/workout/src/core.ts:624

Create a new group of output Groups will stack

Parameters

name?

string = ""

of group

Returns

void

---

output()

output(data): void

Defined in: packages/workout/src/core.ts:645

Emit raw program output, such as a command result

Parameters

data

string

the raw output

Returns

void

---

prependListener()

prependListener<E>(eventName, listener): this

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:311

Adds the listener function to the beginning of the listeners array for the event named eventName. No checks are made to see if the listener has already been added. Multiple calls passing the same combination of eventName and listener will result in the listener being added, and called, multiple times.

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

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

Type Parameters

E

E extends string | symbol

Parameters

eventName

string | symbol

The name of the event.

listener

(...args) => void

The callback function

Returns

this

Since

v6.0.0

Inherited from

EventEmitter.prependListener

---

prependOnceListener()

prependOnceListener<E>(eventName, listener): this

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:328

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

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

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

Type Parameters

E

E extends string | symbol

Parameters

eventName

string | symbol

The name of the event.

listener

(...args) => void

The callback function

Returns

this

Since

v6.0.0

Inherited from

EventEmitter.prependOnceListener

---

rawListeners()

rawListeners<E>(eventName): (...args) => void[]

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:362

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

import { EventEmitter } from 'node:events';
const emitter = new EventEmitter();
emitter.once('log', () => console.log('log once'));

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

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

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

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

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

Type Parameters

E

E extends string | symbol

Parameters

eventName

string | symbol

Returns

(...args) => void[]

Since

v9.4.0

Inherited from

EventEmitter.rawListeners

---

removeAllListeners()

removeAllListeners<E>(eventName?): this

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:374

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.

Type Parameters

E

E extends string | symbol

Parameters

eventName?

string | symbol

Returns

this

Since

v0.1.26

Inherited from

EventEmitter.removeAllListeners

---

removeListener()

removeListener<E>(eventName, listener): this

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:461

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

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

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

Once an event is emitted, all listeners attached to it at the time of emitting are called in order. This implies that any removeListener() or removeAllListeners() calls after emitting and before the last listener finishes execution will not remove them from emit() 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 indexes of any listener registered after the listener being removed. This will not impact the order in which listeners are called, but it means that any copies of the listener array as returned by the emitter.listeners() method will need to be recreated.

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

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

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

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

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

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

Type Parameters

E

E extends string | symbol

Parameters

eventName

string | symbol

listener

(...args) => void

Returns

this

Since

v0.1.26

Inherited from

EventEmitter.removeListener

---

requestInput()

requestInput(title, type?, regexp?, waitFor?, timeout?): Promise<string>

Defined in: packages/workout/src/core.ts:749

Request a user input

Parameters

title

string

of the input

type?

WorkerInputType = WorkerInputType.STRING

the input type

regexp?

(string | RegExp)[] = ...

to validate the input

waitFor?

boolean = true

call waitFor method

timeout?

number = 0

before giving up on input

Returns

Promise<string>

the input request uuid if no waitFor or the input value

---

returnInput()

returnInput(uuid, value): void

Defined in: packages/workout/src/core.ts:820

Send the result of an input To be used by the listeners

Parameters

uuid

string

of input

value

string

entered by user

Returns

void

---

setInteractive()

setInteractive(interactive): void

Defined in: packages/workout/src/core.ts:735

Enable or disable interactive mode for user input

Parameters

interactive

boolean

True to allow user input, false to disable

Returns

void

---

setMaxListeners()

setMaxListeners(n): this

Defined in: node_modules/.pnpm/@types+node@25.5.0/node_modules/@types/node/events.d.ts:472

By default EventEmitters will print a warning if more than 10 listeners are added for a particular event. This is a useful default that helps finding memory leaks. The emitter.setMaxListeners() method allows the limit to be modified for this specific EventEmitter instance. The value can be set to Infinity (or 0) to indicate an unlimited number of listeners.

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

Parameters

n

number

Returns

this

Since

v0.3.5

Inherited from

EventEmitter.setMaxListeners

---

setTitle()

setTitle(title): void

Defined in: packages/workout/src/core.ts:532

Set the output title

Parameters

title

string

to set

Returns

void

---

startActivity()

startActivity(title?, uid?): void

Defined in: packages/workout/src/core.ts:555

Start an undetermined activity

Parameters

title?

string

optional display title

uid?

string = "activity"

unique identifier for the activity

Returns

void

---

startProgress()

startProgress(uid, total, title?): void

Defined in: packages/workout/src/core.ts:543

Start a new progress indicator

Parameters

uid

string

unique identifier for the progress

total

number

total number of steps

title?

string

optional display title

Returns

void

---

stopActivity()

stopActivity(status?, title?, uid?): void

Defined in: packages/workout/src/core.ts:569

Stop an activity

Parameters

status?

"info" | "error" | "success" | "warning"

final status of the activity

title?

string

optional display title to set on completion

uid?

string = "activity"

unique identifier for the activity

Returns

void

---

updateProgress()

updateProgress(current, uid?, title?): void

Defined in: packages/workout/src/core.ts:598

Update a progress indicator

Parameters

current

number

value

uid?

string = ...

id of the progress or default one

title?

string

update title as well

Returns

void

---

waitForInput()

waitForInput(uuid): Promise<string>

Defined in: packages/workout/src/core.ts:803

Wait until an answer is provided

Parameters

uuid

string

of input to wait for

Returns

Promise<string>

the user's input value