WebTransportReceiveStream: getStats() method

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

Note: This feature is available in Web Workers.

The getStats() method of the WebTransportReceiveStream interface asynchronously returns an object containing statistics for the current stream.

The statistics include the total number of ordered bytes that have arrived on this stream (ignoring network overhead, up until the first missing byte) and the total number that have been read by the application. It therefore provides a measure of how quickly the application is consuming bytes from the server on this particular stream.

Syntax

js
getStats()

Parameters

None.

Return value

A Promise that resolves to a object containing statistics about the current stream. The returned object has the following properties:

timestamp

A DOMHighResTimeStamp indicating the timestamp at which the statistics were gathered, relative to Jan 1, 1970, UTC.

bytesReceived

A positive integer indicating the number of bytes received by this stream, up to the first missing byte. The number does not include any network overhead, and can only increase.

bytesRead

A positive integer indicating the number of bytes the application has read from this WebTransportReceiveStream stream. This number can only increase, and is always less than or equal to bytesReceived.

Examples

The code snippet below uses await to wait on the Promise returned by getStats(). When the promise fulfills, the number of bytes that have not yet been read is logged to the console.

js
const stats = await stream.getStats();
const unConsumedBytes = stats.bytesReceived - stats.bytesRead;
console.log(`Bytes in reader queue: ${unConsumedBytes}`);

Specifications

Specification
WebTransport
# dom-webtransportreceivestream-getstats

Browser compatibility

Report problems with this compatibility data on GitHub
desktopmobileserver
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
Deno
getStats
Experimental

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support
No support
No support
Experimental. Expect behavior to change in the future.
User must explicitly enable this feature.