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 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 Workers The 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.
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
open | Chrome Full support 40 | Edge Full support 16 | 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 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.
