CountQueuingStrategy

Available in 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

• highWaterMark Read only
  • : The total number of chunks that can be contained in the internal queue before backpressure is applied.

Instance methods

• size()
  • : Always returns 1.

Examples

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

Browser compatibility

See also

• Streams API
• CountQueuingStrategy() constructor
• Internal queues and queuing strategies