TransformStreamDefaultController.desiredSize
The desiredSize read-only property of the TransformStreamDefaultController interface returns the desired size to fill the queue of the associated ReadableStream.
The internal queue of a ReadableStream contains chunks that have been enqueued, but not yet read.
If the desiredSize is 0 then the queue is full. Therefore you can use this information to manually apply backpressure to manage the queue.
Value
The desired size.