CountQueuingStrategy

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 CountQueuingStrategy interface of the Streams API provides a built-in chunk counting queuing strategy that can be used when constructing streams.

Constructor

CountQueuingStrategy()

Creates a new CountQueuingStrategy object instance.

Instance properties

CountQueuingStrategy.highWaterMark Read only

The total number of chunks that can be contained in the internal queue before backpressure is applied.

Instance methods

CountQueuingStrategy.size()

Always returns 1.

Examples

js
const queueingStrategy = new CountQueuingStrategy({ highWaterMark: 1 });

const writableStream = new WritableStream(
  {
    // Implement the sink
    write(chunk) {
      // …
    },
    close() {
      // …
    },
    abort(err) {
      console.log("Sink error:", err);
    },
  },
  queueingStrategy,
);

const size = queueingStrategy.size();

Specifications

Specification
Streams Standard
# cqs-class

Browser compatibility

BCD tables only load in the browser

See also