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Class: WSServer<T, U>

@appium/types.WSServer

Type parameters

Name Type
T extends typeof WebSocket.WebSocket = typeof WebSocket.WebSocket
U extends typeof IncomingMessage = typeof IncomingMessage

Hierarchy

  • EventEmitter

↳ WSServer

Table of contents

Constructors

Properties

Methods

Constructors

constructor

• new WSServer<T, U>(options?, callback?)

Type parameters

Name Type
T extends typeof WebSocket = typeof WebSocket
U extends typeof IncomingMessage = typeof IncomingMessage

Parameters

Name Type
options? ServerOptions<T, U>
callback? () => void

Overrides

EventEmitter.constructor

Defined in

node_modules/@types/ws/index.d.ts:358

Properties

clients

• clients: Set<InstanceType<T>>

Defined in

node_modules/@types/ws/index.d.ts:356

options

• options: ServerOptions<T, U>

Defined in

node_modules/@types/ws/index.d.ts:354

path

• path: string

Defined in

node_modules/@types/ws/index.d.ts:355

captureRejectionSymbol

▪ Static Readonly captureRejectionSymbol: typeof captureRejectionSymbol

Inherited from

EventEmitter.captureRejectionSymbol

Defined in

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

captureRejections

▪ Static captureRejections: boolean

Sets or gets the default captureRejection value for all emitters.

Inherited from

EventEmitter.captureRejections

Defined in

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

defaultMaxListeners

▪ Static defaultMaxListeners: number

Inherited from

EventEmitter.defaultMaxListeners

Defined in

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

EventEmitter.errorMonitor

Defined in

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

Methods

addListener

▸ addListener(event, cb): WSServer<T, U>

Parameters

Name Type
event "connection"
cb (client: InstanceType<T>, request: InstanceType<U>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.addListener

Defined in

node_modules/@types/ws/index.d.ts:389

▸ addListener(event, cb): WSServer<T, U>

Parameters

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

Returns

WSServer<T, U>

Overrides

EventEmitter.addListener

Defined in

node_modules/@types/ws/index.d.ts:390

▸ addListener(event, cb): WSServer<T, U>

Parameters

Name Type
event "headers"
cb (headers: string[], request: InstanceType<U>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.addListener

Defined in

node_modules/@types/ws/index.d.ts:391

▸ addListener(event, cb): WSServer<T, U>

Parameters

Name Type
event "close" | "listening"
cb () => void

Returns

WSServer<T, U>

Overrides

EventEmitter.addListener

Defined in

node_modules/@types/ws/index.d.ts:392

▸ addListener(event, listener): WSServer<T, U>

Parameters

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

Returns

WSServer<T, U>

Overrides

EventEmitter.addListener

Defined in

node_modules/@types/ws/index.d.ts:393

address

▸ address(): string | AddressInfo

Returns

string | AddressInfo

Defined in

node_modules/@types/ws/index.d.ts:360

close

▸ close(cb?): void

Parameters

Name Type
cb? (err?: Error) => void

Returns

void

Defined in

node_modules/@types/ws/index.d.ts:361

emit

▸ emit(eventName, ...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.

const EventEmitter = require('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

Since

v0.1.26

Parameters

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

Returns

boolean

Inherited from

EventEmitter.emit

Defined in

node_modules/@types/node/events.d.ts:610

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) ]

Since

v6.0.0

Returns

(string | symbol)[]

Inherited from

EventEmitter.eventNames

Defined in

node_modules/@types/node/events.d.ts:673

getMaxListeners

▸ getMaxListeners(): number

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

Since

v1.0.0

Returns

number

Inherited from

EventEmitter.getMaxListeners

Defined in

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

handleUpgrade

▸ handleUpgrade(request, socket, upgradeHead, callback): void

Parameters

Name Type
request InstanceType<U>
socket Duplex
upgradeHead Buffer
callback (client: InstanceType<T>, request: InstanceType<U>) => void

Returns

void

Defined in

node_modules/@types/ws/index.d.ts:362

listenerCount

▸ listenerCount(eventName, listener?): number

Returns the number of listeners listening to 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.

Since

v3.2.0

Parameters

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

Returns

number

Inherited from

EventEmitter.listenerCount

Defined in

node_modules/@types/node/events.d.ts:620

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] ]

Since

v0.1.26

Parameters

Name Type
eventName string | symbol

Returns

Function[]

Inherited from

EventEmitter.listeners

Defined in

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

off

▸ off(event, cb): WSServer<T, U>

Parameters

Name Type
event "connection"
cb (this: WSServer<T, typeof IncomingMessage>, socket: InstanceType<T>, request: InstanceType<U>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.off

Defined in

node_modules/@types/ws/index.d.ts:383

▸ off(event, cb): WSServer<T, U>

Parameters

Name Type
event "error"
cb (this: WSServer<T, typeof IncomingMessage>, error: Error) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.off

Defined in

node_modules/@types/ws/index.d.ts:384

▸ off(event, cb): WSServer<T, U>

Parameters

Name Type
event "headers"
cb (this: WSServer<T, typeof IncomingMessage>, headers: string[], request: InstanceType<U>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.off

Defined in

node_modules/@types/ws/index.d.ts:385

▸ off(event, cb): WSServer<T, U>

Parameters

Name Type
event "close" | "listening"
cb (this: WSServer<T, typeof IncomingMessage>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.off

Defined in

node_modules/@types/ws/index.d.ts:386

▸ off(event, listener): WSServer<T, U>

Parameters

Name Type
event string | symbol
listener (this: WSServer<T, typeof IncomingMessage>, ...args: any[]) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.off

Defined in

node_modules/@types/ws/index.d.ts:387

on

▸ on(event, cb): WSServer<T, U>

Parameters

Name Type
event "connection"
cb (this: WSServer<T, typeof IncomingMessage>, socket: InstanceType<T>, request: InstanceType<U>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.on

Defined in

node_modules/@types/ws/index.d.ts:371

▸ on(event, cb): WSServer<T, U>

Parameters

Name Type
event "error"
cb (this: WSServer<T, typeof IncomingMessage>, error: Error) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.on

Defined in

node_modules/@types/ws/index.d.ts:372

▸ on(event, cb): WSServer<T, U>

Parameters

Name Type
event "headers"
cb (this: WSServer<T, typeof IncomingMessage>, headers: string[], request: InstanceType<U>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.on

Defined in

node_modules/@types/ws/index.d.ts:373

▸ on(event, cb): WSServer<T, U>

Parameters

Name Type
event "close" | "listening"
cb (this: WSServer<T, typeof IncomingMessage>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.on

Defined in

node_modules/@types/ws/index.d.ts:374

▸ on(event, listener): WSServer<T, U>

Parameters

Name Type
event string | symbol
listener (this: WSServer<T, typeof IncomingMessage>, ...args: any[]) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.on

Defined in

node_modules/@types/ws/index.d.ts:375

once

▸ once(event, cb): WSServer<T, U>

Parameters

Name Type
event "connection"
cb (this: WSServer<T, typeof IncomingMessage>, socket: InstanceType<T>, request: InstanceType<U>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.once

Defined in

node_modules/@types/ws/index.d.ts:377

▸ once(event, cb): WSServer<T, U>

Parameters

Name Type
event "error"
cb (this: WSServer<T, typeof IncomingMessage>, error: Error) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.once

Defined in

node_modules/@types/ws/index.d.ts:378

▸ once(event, cb): WSServer<T, U>

Parameters

Name Type
event "headers"
cb (this: WSServer<T, typeof IncomingMessage>, headers: string[], request: InstanceType<U>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.once

Defined in

node_modules/@types/ws/index.d.ts:379

▸ once(event, cb): WSServer<T, U>

Parameters

Name Type
event "close" | "listening"
cb (this: WSServer<T, typeof IncomingMessage>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.once

Defined in

node_modules/@types/ws/index.d.ts:380

▸ once(event, listener): WSServer<T, U>

Parameters

Name Type
event string | symbol
listener (this: WSServer<T, typeof IncomingMessage>, ...args: any[]) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.once

Defined in

node_modules/@types/ws/index.d.ts:381

prependListener

▸ prependListener(eventName, listener): WSServer<T, U>

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.

Since

v6.0.0

Parameters

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

Returns

WSServer<T, U>

Inherited from

EventEmitter.prependListener

Defined in

node_modules/@types/node/events.d.ts:638

prependOnceListener

▸ prependOnceListener(eventName, listener): WSServer<T, U>

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.

Since

v6.0.0

Parameters

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

Returns

WSServer<T, U>

Inherited from

EventEmitter.prependOnceListener

Defined in

node_modules/@types/node/events.d.ts:654

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');

Since

v9.4.0

Parameters

Name Type
eventName string | symbol

Returns

Function[]

Inherited from

EventEmitter.rawListeners

Defined in

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

removeAllListeners

▸ removeAllListeners(event?): WSServer<T, U>

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.

Since

v0.1.26

Parameters

Name Type
event? string | symbol

Returns

WSServer<T, U>

Inherited from

EventEmitter.removeAllListeners

Defined in

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

removeListener

▸ removeListener(event, cb): WSServer<T, U>

Parameters

Name Type
event "connection"
cb (client: InstanceType<T>, request: InstanceType<U>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.removeListener

Defined in

node_modules/@types/ws/index.d.ts:395

▸ removeListener(event, cb): WSServer<T, U>

Parameters

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

Returns

WSServer<T, U>

Overrides

EventEmitter.removeListener

Defined in

node_modules/@types/ws/index.d.ts:396

▸ removeListener(event, cb): WSServer<T, U>

Parameters

Name Type
event "headers"
cb (headers: string[], request: InstanceType<U>) => void

Returns

WSServer<T, U>

Overrides

EventEmitter.removeListener

Defined in

node_modules/@types/ws/index.d.ts:397

▸ removeListener(event, cb): WSServer<T, U>

Parameters

Name Type
event "close" | "listening"
cb () => void

Returns

WSServer<T, U>

Overrides

EventEmitter.removeListener

Defined in

node_modules/@types/ws/index.d.ts:398

▸ removeListener(event, listener): WSServer<T, U>

Parameters

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

Returns

WSServer<T, U>

Overrides

EventEmitter.removeListener

Defined in

node_modules/@types/ws/index.d.ts:399

setMaxListeners

▸ setMaxListeners(n): WSServer<T, U>

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.

Since

v0.3.5

Parameters

Name Type
n number

Returns

WSServer<T, U>

Inherited from

EventEmitter.setMaxListeners

Defined in

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

shouldHandle

▸ shouldHandle(request): boolean | Promise<boolean>

Parameters

Name Type
request InstanceType<U>

Returns

boolean | Promise<boolean>

Defined in

node_modules/@types/ws/index.d.ts:368

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]
}

Since

v15.2.0, v14.17.0

Parameters

Name Type
emitter EventEmitter | _DOMEventTarget
name string | symbol

Returns

Function[]

Inherited from

EventEmitter.getEventListeners

Defined in

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

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

Since

v0.9.12

Deprecated

Since v3.2.0 - Use listenerCount instead.

Parameters

Name Type Description
emitter EventEmitter The emitter to query
eventName string | symbol The event name

Returns

number

Inherited from

EventEmitter.listenerCount

Defined in

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

on

▸ Static on(emitter, eventName, options?): AsyncIterableIterator<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());

Since

v13.6.0, v12.16.0

Parameters

Name Type Description
emitter EventEmitter -
eventName string The name of the event being listened for
options? StaticEventEmitterOptions -

Returns

AsyncIterableIterator<any>

that iterates eventName events emitted by the emitter

Inherited from

EventEmitter.on

Defined in

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

once

▸ 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!

Since

v11.13.0, v10.16.0

Parameters

Name Type
emitter _NodeEventTarget
eventName string | symbol
options? StaticEventEmitterOptions

Returns

Promise<any[]>

Inherited from

EventEmitter.once

Defined in

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

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

Parameters

Name Type
emitter _DOMEventTarget
eventName string
options? StaticEventEmitterOptions

Returns

Promise<any[]>

Inherited from

EventEmitter.once

Defined in

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);

Since

v15.4.0

Parameters

Name Type Description
n? number A non-negative number. The maximum number of listeners per EventTarget event.
...eventTargets (EventEmitter | _DOMEventTarget)[] -

Returns

void

Inherited from

EventEmitter.setMaxListeners

Defined in

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