WritableStreamDefaultController

Baseline 2022

Newly available

Since June 2022, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.

Note: This feature is available in Web Workers.

The WritableStreamDefaultController interface of the Streams API represents a controller allowing control of a WritableStream's state. When constructing a WritableStream, the underlying sink is given a corresponding WritableStreamDefaultController instance to manipulate.

Constructor

None. WritableStreamDefaultController instances are created automatically during WritableStream construction.

Instance properties

WritableStreamDefaultController.signal Read only: Returns the AbortSignal associated with the controller.

Instance methods

WritableStreamDefaultController.error(): Causes any future interactions with the associated stream to error.

Examples

const writableStream = new WritableStream({
  start(controller) {
    // do stuff with controller

    // error stream if necessary
    controller.error("My stream is broken");
  },
  write(chunk, controller) {
    // ...
  },
  close(controller) {
    // ...
  },
  abort(err) {
    // ...
  },
});

Specifications

Specification
Streams Standard # ws-default-controller-class

Browser compatibility

BCD tables only load in the browser