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 index read-only property of the ServiceWorkerRegistration interface returns a reference to the ContentIndex interface, which allows for indexing of offline content.
A ContentIndex object.
You can access the property from either your main script or the registered service worker.
Here is an example from the main script:
// reference registration
const registration = await navigator.serviceWorker.ready;
// feature detection
if ("index" in registration) {
// Content Index API functionality
const contentIndex = registration.index;
}
From the service worker:
// service worker script const contentIndex = self.registration.index;
| Specification |
|---|
| Content Index> # dom-serviceworkerregistration-index> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
index |
No | No | No | No | No | 84 | No | 60 | No | 14.0 | 84 | No |
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https://developer.mozilla.org/en-US/docs/Web/API/ServiceWorkerRegistration/index