The ready
read-only property of the ServiceWorkerContainer
interface provides a way of delaying code execution until a service worker is active. It returns a Promise
that will never reject, and which waits indefinitely until the ServiceWorkerRegistration
associated with the current page has an active
worker. Once that condition is met, it resolves with the ServiceWorkerRegistration
.
Syntax
navigator.serviceWorker.ready.then(function(serviceWorkerRegistration) { ... });
Value
A Promise
that will never reject, and which may eventually resolve with a ServiceWorkerRegistration
.
Example
if ('serviceWorker' in navigator) { navigator.serviceWorker.ready .then(function(registration) { console.log('A service worker is active:', registration.active); // At this point, you can call methods that require an active // service worker, like registration.pushManager.subscribe() }); } else { console.log('Service workers are not supported.'); }
Specifications
Specification | Status | Comment |
---|---|---|
Service Workers The definition of 'ServiceWorkerRegistration.ready' in that specification. |
Working Draft | Initial definition. |
Browser compatibility
The compatibility table on 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 | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
ready | Chrome Full support 40 | Edge
Full support
17
| Firefox
Full support
44
| IE No support No | Opera Full support 27 | Safari Full support 11.1 | WebView Android Full support 40 | Chrome Android Full support 40 | Firefox Android Full support 44 | Opera Android Full support 27 | Safari iOS Full support 11.3 | Samsung Internet Android Full support 4.0 |
Legend
- Full support
- Full support
- No support
- No support
- Experimental. Expect behavior to change in the future.
- Experimental. Expect behavior to change in the future.
- See implementation notes.
- See implementation notes.
- User must explicitly enable this feature.
- User must explicitly enable this feature.