Cache.put()

The put() method of the Cache interface allows key/value pairs to be added to the current Cache object.

Often, you will just want to fetch() one or more requests, then add the result straight to your cache. In such cases you are better off just using Cache.add/Cache.addAll, as they are shorthand functions for one or more of these operations:

fetch(url).then(function (response) {
  if (!response.ok) {
    throw new TypeError('bad response status');
  }
  return cache.put(url, response);
})

Syntax

cache.put(request, response).then(function() {
  // request/response pair has been added to the cache
});

Returns

A promise that resolves with void.

Parameters

request

The Request you want to add to the cache.

response

The Response you want to match up to the request.

Examples

This code snippet is from the MDN sw-test example (see sw-test running live). Here we wait for a FetchEvent to fire. We construct a custom response like so:

1. Check whether a match for the request is found in the CacheStorage using CacheStorage.match. If so, serve that.
2. If not, open the v1 cache using open(), put the default network request in the cache using Cache.put and return a clone of the default network request using return response.clone() — necessary because put() consumes the response body.
3. If this fails (e.g., because the network is down), return a fallback response.

var response;
var cachedResponse = caches.match(event.request).catch(function() {
  return fetch(event.request);
}).then(function(r) {
  response = r;
  caches.open('v1').then(function(cache) {
    cache.put(event.request, response);
  });  
  return response.clone();
}).catch(function() {
  return caches.match('/sw-test/gallery/myLittleVader.jpg');
});

Specifications

Browser compatibility

[1] Service workers (and Push) have been disabled in the Firefox 45 & 52 Extended Support Releases (ESR.)

See also

• Using Service Workers
• Cache
• WorkerGlobalScope.caches