ReadableStreamDefaultController: desiredSize property
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since January 2020.
Note: This feature is available in Web Workers.
The desiredSize read-only property of the
ReadableStreamDefaultController interface returns the desired size
required to fill the stream's internal queue.
Value
An integer. Note that this can be negative if the queue is over-full.
Examples
The A readable stream with an underlying push source and backpressure support example in the spec
provides a good example of using desiredSize to manually detect when the
stream is full and apply backpressure, and also of using
ReadableStreamDefaultController.error() to manually trigger a stream
error if another part of the system it relies on fails.
Specifications
| Specification |
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| Streams # ref-for-rs-default-controller-desired-size② |
Browser compatibility
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desiredSize
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Legend
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- Full support
- Full support