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 reliability read-only property of the WebTransport interface indicates whether the connection supports reliable transports only, or whether it also supports unreliable transports (such as UDP).
A string with one of the following values:
pendingThe connection has not yet been established. The reliability is not yet known.
reliable-onlyThe connection only supports reliable transports.
supports-unreliableThe connection supports both unreliable and reliable transports.
const url = "https://example.com:4999/wt";
async function initTransport(url) {
// Initialize transport connection
const transport = new WebTransport(url);
// Once ready fulfils the connection can be used
// Prior to this the reliability is "pending"
await transport.ready;
if (transport.reliability === "reliable-only") {
// Use connection only with reliable transports
} else {
// Use connection with either reliable or unreliable transports.
}
// …
}
| Specification |
|---|
| WebTransport> # dom-webtransport-reliability> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
reliability |
No | No | 114 | No | 18.4 | No | 114 | No | 18.4 | No | No | No |
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https://developer.mozilla.org/en-US/docs/Web/API/WebTransport/reliability