Interface Worker

The Worker class represents a WebWorker. worker event is emitted on the page object to signal a worker creation. close event is emitted on the worker object when the worker is gone.

page.on('worker', worker => {
  console.log('Worker created: ' + worker.url());
  worker.on('close', worker => console.log('Worker destroyed: ' + worker.url()));
});

console.log('Current workers:');
for (const worker of page.workers())
  console.log('  ' + worker.url());

interface Worker {
    addListener(event: "close", listener: (worker: Worker) => any): this;
    addListener(
        event: "console",
        listener: (consoleMessage: ConsoleMessage) => any,
    ): this;
    evaluate<R, Arg>(pageFunction: PageFunction<Arg, R>, arg: Arg): Promise<R>;
    evaluate<R>(pageFunction: PageFunction<void, R>, arg?: any): Promise<R>;
    evaluateHandle<R, Arg>(
        pageFunction: PageFunction<Arg, R>,
        arg: Arg,
    ): Promise<SmartHandle<R>>;
    evaluateHandle<R>(
        pageFunction: PageFunction<void, R>,
        arg?: any,
    ): Promise<SmartHandle<R>>;
    off(event: "close", listener: (worker: Worker) => any): this;
    off(
        event: "console",
        listener: (consoleMessage: ConsoleMessage) => any,
    ): this;
    on(event: "close", listener: (worker: Worker) => any): this;
    on(
        event: "console",
        listener: (consoleMessage: ConsoleMessage) => any,
    ): this;
    once(event: "close", listener: (worker: Worker) => any): this;
    once(
        event: "console",
        listener: (consoleMessage: ConsoleMessage) => any,
    ): this;
    prependListener(event: "close", listener: (worker: Worker) => any): this;
    prependListener(
        event: "console",
        listener: (consoleMessage: ConsoleMessage) => any,
    ): this;
    removeListener(event: "close", listener: (worker: Worker) => any): this;
    removeListener(
        event: "console",
        listener: (consoleMessage: ConsoleMessage) => any,
    ): this;
    url(): string;
    waitForEvent(
        event: "close",
        optionsOrPredicate?:
            | {
                predicate?: (worker: Worker) => boolean | Promise<boolean>;
                signal?: AbortSignal;
                timeout?: number;
            }
            | ((worker: Worker) => boolean | Promise<boolean>),
    ): Promise<Worker>;
    waitForEvent(
        event: "console",
        optionsOrPredicate?:
            | {
                predicate?: (
                    consoleMessage: ConsoleMessage,
                ) => boolean | Promise<boolean>;
                signal?: AbortSignal;
                timeout?: number;
            }
            | ((consoleMessage: ConsoleMessage) => boolean | Promise<boolean>),
    ): Promise<ConsoleMessage>;
}

Index

Methods

addListener evaluate evaluateHandle off on once prependListener removeListener url waitForEvent

Methods

addListener

addListener(event: "close", listener: (worker: Worker) => any): this
Emitted when this dedicated WebWorker is terminated.
Parameters
- event: "close"
- listener: (worker: Worker) => any
Returns this
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11703
addListener(
event: "console",
listener: (consoleMessage: ConsoleMessage) => any,
): this
Emitted when JavaScript within the worker calls one of console API methods, e.g. console.log or console.dir.
Parameters
- event: "console"
- listener: (consoleMessage: ConsoleMessage) => any
Returns this
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11708

evaluate

evaluate<R, Arg>(pageFunction: PageFunction<Arg, R>, arg: Arg): Promise<R>
Returns the return value of pageFunction.

If the function passed to the worker.evaluate(pageFunction[, arg]) returns a [Promise], then worker.evaluate(pageFunction[, arg]) would wait for the promise to resolve and return its value.

If the function passed to the worker.evaluate(pageFunction[, arg]) returns a non-[Serializable] value, then worker.evaluate(pageFunction[, arg]) returns undefined. Playwright also supports transferring some additional values that are not serializable by JSON: -0, NaN, Infinity, -Infinity.
Type Parameters
- R
- Arg
Parameters
- pageFunction: PageFunction<Arg, R>
  Function to be evaluated in the worker context.
- arg: Arg
  Optional argument to pass to pageFunction.
Returns Promise<R>
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11611
evaluate<R>(pageFunction: PageFunction<void, R>, arg?: any): Promise<R>
Returns the return value of pageFunction.

If the function passed to the worker.evaluate(pageFunction[, arg]) returns a [Promise], then worker.evaluate(pageFunction[, arg]) would wait for the promise to resolve and return its value.

If the function passed to the worker.evaluate(pageFunction[, arg]) returns a non-[Serializable] value, then worker.evaluate(pageFunction[, arg]) returns undefined. Playwright also supports transferring some additional values that are not serializable by JSON: -0, NaN, Infinity, -Infinity.
Type Parameters
- R
Parameters
- pageFunction: PageFunction<void, R>
  Function to be evaluated in the worker context.
- Optionalarg: any
  Optional argument to pass to pageFunction.
Returns Promise<R>
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11632

evaluateHandle

evaluateHandle<R, Arg>(
pageFunction: PageFunction<Arg, R>,
arg: Arg,
): Promise<SmartHandle<R>>
Returns the return value of pageFunction as a JSHandle.

The only difference between worker.evaluate(pageFunction[, arg]) and worker.evaluateHandle(pageFunction[, arg]) is that worker.evaluateHandle(pageFunction[, arg]) returns JSHandle.

If the function passed to the worker.evaluateHandle(pageFunction[, arg]) returns a [Promise], then worker.evaluateHandle(pageFunction[, arg]) would wait for the promise to resolve and return its value.
Type Parameters
- R
- Arg
Parameters
- pageFunction: PageFunction<Arg, R>
  Function to be evaluated in the worker context.
- arg: Arg
  Optional argument to pass to pageFunction.
Returns Promise<SmartHandle<R>>
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11655
evaluateHandle<R>(
pageFunction: PageFunction<void, R>,
arg?: any,
): Promise<SmartHandle<R>>
Returns the return value of pageFunction as a JSHandle.

The only difference between worker.evaluate(pageFunction[, arg]) and worker.evaluateHandle(pageFunction[, arg]) is that worker.evaluateHandle(pageFunction[, arg]) returns JSHandle.

If the function passed to the worker.evaluateHandle(pageFunction[, arg]) returns a [Promise], then worker.evaluateHandle(pageFunction[, arg]) would wait for the promise to resolve and return its value.
Type Parameters
- R
Parameters
- pageFunction: PageFunction<void, R>
  Function to be evaluated in the worker context.
- Optionalarg: any
  Optional argument to pass to pageFunction.
Returns Promise<SmartHandle<R>>
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11677

off

off(event: "close", listener: (worker: Worker) => any): this
Removes an event listener added by on or addListener.
Parameters
- event: "close"
- listener: (worker: Worker) => any
Returns this
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11723
off(event: "console", listener: (consoleMessage: ConsoleMessage) => any): this
Removes an event listener added by on or addListener.
Parameters
- event: "console"
- listener: (consoleMessage: ConsoleMessage) => any
Returns this
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11728

on

on(event: "close", listener: (worker: Worker) => any): this
Emitted when this dedicated WebWorker is terminated.
Parameters
- event: "close"
- listener: (worker: Worker) => any
Returns this
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11682
on(event: "console", listener: (consoleMessage: ConsoleMessage) => any): this
Emitted when JavaScript within the worker calls one of console API methods, e.g. console.log or console.dir.
Parameters
- event: "console"
- listener: (consoleMessage: ConsoleMessage) => any
Returns this
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11687

once

once(event: "close", listener: (worker: Worker) => any): this
Adds an event listener that will be automatically removed after it is triggered once. See addListener for more information about this event.
Parameters
- event: "close"
- listener: (worker: Worker) => any
Returns this
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11692
once(event: "console", listener: (consoleMessage: ConsoleMessage) => any): this
Adds an event listener that will be automatically removed after it is triggered once. See addListener for more information about this event.
Parameters
- event: "console"
- listener: (consoleMessage: ConsoleMessage) => any
Returns this
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11697

prependListener

prependListener(event: "close", listener: (worker: Worker) => any): this
Emitted when this dedicated WebWorker is terminated.
Parameters
- event: "close"
- listener: (worker: Worker) => any
Returns this
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11734
prependListener(
event: "console",
listener: (consoleMessage: ConsoleMessage) => any,
): this
Emitted when JavaScript within the worker calls one of console API methods, e.g. console.log or console.dir.
Parameters
- event: "console"
- listener: (consoleMessage: ConsoleMessage) => any
Returns this
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11739

removeListener

removeListener(event: "close", listener: (worker: Worker) => any): this
Removes an event listener added by on or addListener.
Parameters
- event: "close"
- listener: (worker: Worker) => any
Returns this
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11713
removeListener(
event: "console",
listener: (consoleMessage: ConsoleMessage) => any,
): this
Removes an event listener added by on or addListener.
Parameters
- event: "console"
- listener: (consoleMessage: ConsoleMessage) => any
Returns this
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11718

url

url(): string
Returns string
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11741

waitForEvent

waitForEvent(
    event: "close",
    optionsOrPredicate?:
        | {
            predicate?: (worker: Worker) => boolean | Promise<boolean>;
            signal?: AbortSignal;
            timeout?: number;
        }
        | ((worker: Worker) => boolean | Promise<boolean>),
): Promise<Worker>
Emitted when this dedicated WebWorker is terminated.
Parameters
- event: "close"
- OptionaloptionsOrPredicate:
      | {
          predicate?: (worker: Worker) => boolean | Promise<boolean>;
          signal?: AbortSignal;
          timeout?: number;
      }
      | ((worker: Worker) => boolean | Promise<boolean>)
Returns Promise<Worker>
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11747
waitForEvent(
    event: "console",
    optionsOrPredicate?:
        | {
            predicate?: (
                consoleMessage: ConsoleMessage,
            ) => boolean | Promise<boolean>;
            signal?: AbortSignal;
            timeout?: number;
        }
        | ((consoleMessage: ConsoleMessage) => boolean | Promise<boolean>),
): Promise<ConsoleMessage>
Emitted when JavaScript within the worker calls one of console API methods, e.g. console.log or console.dir.
Parameters
- event: "console"
- OptionaloptionsOrPredicate:
      | {
          predicate?: (
              consoleMessage: ConsoleMessage,
          ) => boolean | Promise<boolean>;
          signal?: AbortSignal;
          timeout?: number;
      }
      | ((consoleMessage: ConsoleMessage) => boolean | Promise<boolean>)
Returns Promise<ConsoleMessage>
- Defined in node_modules/.pnpm/playwright-core@1.62.1/node_modules/playwright-core/types/types.d.ts:11752

Interface Worker

Index

Methods

Methods

addListener

Parameters

Returns this

Parameters

Returns this

evaluate

Type Parameters

Parameters

Returns Promise<R>

Type Parameters

Parameters

Returns Promise<R>

evaluateHandle

Type Parameters

Parameters

Returns Promise<SmartHandle<R>>

Type Parameters

Parameters

Returns Promise<SmartHandle<R>>

off

Parameters

Returns this

Parameters

Returns this

on

Parameters

Returns this

Parameters

Returns this

once

Parameters

Returns this

Parameters

Returns this

prependListener

Parameters

Returns this

Parameters

Returns this

removeListener

Parameters

Returns this

Parameters

Returns this

url

Returns string

waitForEvent

Parameters

Returns Promise<Worker>

Parameters

Returns Promise<ConsoleMessage>

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