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.
CountQueuingStrategy()Creates a new CountQueuingStrategy object instance.
CountQueuingStrategy.highWaterMark Read onlyThe total number of chunks that can be contained in the internal queue before backpressure is applied.
CountQueuingStrategy.size()Always returns 1.
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();