The desiredSize
read-only property of the ReadableStreamDefaultController
interface returns the desired size required to fill the stream's internal queue.
Syntax
var desiredSize =
readableStreamDefaultController.desiredSize;
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 | Status | Comment |
---|---|---|
Streams The definition of 'desiredSize' in that specification. |
Living Standard | Initial definition. |
Browser compatibility
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
desiredSize | Chrome ? | Edge ? | Firefox
Full support
65
| IE ? | Opera ? | Safari ? | WebView Android ? | Chrome Android ? | Firefox Android
Full support
65
| Opera Android ? | Safari iOS ? | Samsung Internet Android ? |
Legend
- Full support
- Full support
- Compatibility unknown
- Compatibility unknown
- Experimental. Expect behavior to change in the future.
- Experimental. Expect behavior to change in the future.
- User must explicitly enable this feature.
- User must explicitly enable this feature.