The open()
method of the CacheStorage
interface returns a Promise
that resolves to the Cache
object matching the cacheName
.
You can access CacheStorage
through the global caches
property.
Note: If the specified Cache
does not exist, a new cache is created with that cacheName
and a Promise
that resolves to this new Cache
object is returned.
Syntax
caches.open(cacheName).then(function(cache) { // Do something with your cache });
Parameters
- cacheName
- The name of the cache you want to open.
Return value
A Promise
that resolves to the requested Cache
object.
Examples
This example is from the MDN sw-test example (see [[../../../../../../../mdn.github.io/sw-test/index|sw-test running live]]). Here we wait for an InstallEvent
to fire, then runs waitUntil()
to handle the install process for the app. This consists of calling CacheStorage.open()
to create a new cache, then using Cache.addAll()
to add a series of assets to it.
self.addEventListener('install', function(event) {
event.waitUntil(
caches.open('v1').then(function(cache) {
return cache.addAll([
'/sw-test/',
'/sw-test/index.html',
'/sw-test/style.css',
'/sw-test/app.js',
'/sw-test/image-list.js',
'/sw-test/star-wars-logo.jpg',
'/sw-test/gallery/bountyHunters.jpg',
'/sw-test/gallery/myLittleVader.jpg',
'/sw-test/gallery/snowTroopers.jpg'
]);
})
);
Specifications
Specification | Status | Comment |
Service WorkersThe definition of 'CacheStorage: open' 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.
Update compatibility data on GitHub
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Chrome
Full support 40 |
Edge
Full support 16 |
Firefox Full support 44 Full support 44 Notes' Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API. |
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 Yes |
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.
See also
CacheStorage.open() by Mozilla Contributors is licensed under CC-BY-SA 2.5.