ServiceWorkerRegistration.update
The update
method of the ServiceWorkerRegistration
interface attempts to update the service worker. It fetches the worker's script URL, and if the new worker is not byte-by-byte identical to the current worker, it installs the new worker. The fetch of the worker bypasses any browser caches if the previous fetch occurred over 24 hours ago.
Syntax
ServiceWorkerRegistration.update();
Parameters
None.
Returns
Void.
Example
The following simple example registers a service worker example, an then adds an event handler to a button so you can explicitly update the service worker whenever desired:
if ('serviceWorker' in navigator) {
navigator.serviceWorker.register('/sw-test/sw.js', {scope: 'sw-test'}).then(function(registration) {
// registration worked
console.log('Registration succeeded.');
button.onclick = function() {
registration.update();
}
}).catch(function(error) {
// registration failed
console.log('Registration failed with ' + error);
});
};
Specifications
|
Desktop |
|
Chrome |
Edge |
Firefox |
Internet Explorer |
Opera |
Safari |
Basic support
|
45
- 45
- Starting with Chrome 46, update() returns a promise that resolves with 'undefined' if the operation completed successfully or there was no update, and rejects if update failed. If the new worker ran but installation failed, the promise still resolves. Formerly, it raised an exception.
- Before Chrome 48, this method always bypassed the browser cache. Starting with Chrome 48, it only bypasses the cache when the previous service worker check was more than twenty-four hours ago.
|
17
- 17
- 16
Disabled
- Disabled From version 16: this feature is behind the
Enable service workers preference.
|
44
- 44
- Service workers (and Push) have been disabled in the Firefox 45 and 52 Extended Support Releases (ESR).
|
No |
32
- 32
- Starting with Opera 33, update() returns a promise that resolves with 'undefined' if the operation completed successfully or there was no update, and rejects if update failed. If the new worker ran but installation failed, the promise still resolves. Formerly, it raised an exception.
- Before Opera 35, this method always bypassed the browser cache. Starting with Opera 35, it only bypasses the cache when the previous service worker check was more than twenty-four hours ago.
|
No |
|
Mobile |
|
Android webview |
Chrome for Android |
Edge Mobile |
Firefox for Android |
Opera for Android |
iOS Safari |
Samsung Internet |
Basic support
|
45
- 45
- Starting with Chrome 46, update() returns a promise that resolves with 'undefined' if the operation completed successfully or there was no update, and rejects if update failed. If the new worker ran but installation failed, the promise still resolves. Formerly, it raised an exception.
- Before Chrome 48, this method always bypassed the browser cache. Starting with Chrome 48, it only bypasses the cache when the previous service worker check was more than twenty-four hours ago.
|
45
- 45
- Starting with Chrome 46, update() returns a promise that resolves with 'undefined' if the operation completed successfully or there was no update, and rejects if update failed. If the new worker ran but installation failed, the promise still resolves. Formerly, it raised an exception.
- Before Chrome 48, this method always bypassed the browser cache. Starting with Chrome 48, it only bypasses the cache when the previous service worker check was more than twenty-four hours ago.
|
? |
44 |
32
- 32
- Starting with Opera 33, update() returns a promise that resolves with 'undefined' if the operation completed successfully or there was no update, and rejects if update failed. If the new worker ran but installation failed, the promise still resolves. Formerly, it raised an exception.
- Before Opera 35, this method always bypassed the browser cache. Starting with Opera 35, it only bypasses the cache when the previous service worker check was more than twenty-four hours ago.
|
No |
4.0 |
See also