---
title: CacheStorage.open()
slug: Web/API/CacheStorage/open
tags:
  - API
  - CacheStorage
  - Experimental
  - Method
  - Reference
  - ServiceWorker
translation_of: Web/API/CacheStorage/open
---
<p>{{APIRef("Service Workers API")}}{{SeeCompatTable}}</p>

<p><strong><code>open()</code></strong> метод из {{domxref("CacheStorage")}} интерфейса возвращает {{jsxref("Promise")}} который резолвится в {{domxref("Cache")}} объект с соответствующим <code>cacheName (именем тега кеша)</code>.</p>

<div class="note">
<p><strong>Note</strong>: If the specified {{domxref("Cache")}} does not exist, a new cache is created with that <code>cacheName</code>.</p>
</div>

<h2 id="Синтаксис">Синтаксис</h2>

<pre class="syntaxbox">caches.open(<em>cacheName</em>).then(function(<em>cache</em>) {
  //обрабатываем кеш например: cache.AddAll(filesToCache); где filesToCache = ['/mypic.png', ...]
});
</pre>

<h3 id="Возвращает">Возвращает</h3>

<p>{{jsxref("Promise")}} который резолвится в запрашиваемый {{domxref("Cache")}} объект.</p>

<h3 id="Параметры">Параметры</h3>

<dl>
 <dt>cacheName</dt>
 <dd>Имя (тег) кеша заданное заранее которое необходимо открыть.</dd>
</dl>

<h2 id="Примеры" style="line-height: 30px; font-size: 2.14285714285714rem;">Примеры</h2>

<p>This code snippet is from the MDN <a href="https://github.com/mdn/sw-test/">sw-test example</a> (see <a href="https://mdn.github.io/sw-test/">sw-test running live</a>). Here we wait for a {{domxref("FetchEvent")}} to fire. Then we construct a custom response like so:</p>

<ol>
 <li>Check whether a match for the request is found in the {{domxref("CacheStorage")}} using {{domxref("CacheStorage.match")}}. If so, serve that.</li>
 <li>If not, open the <code>v1</code> cache using {{domxref("CacheStorage.open")}}, put the default network request in the cache using {{domxref("Cache.put")}} and return a clone of the default network request using <code>return response.clone()</code> — necessary because <code>put()</code> consumes the response body.</li>
 <li>If this fails (e.g., because the network is down), return a fallback response.</li>
</ol>

<pre class="brush: js">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');
});</pre>

<h2 id="Specifications">Specifications</h2>

<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">Specification</th>
   <th scope="col">Status</th>
   <th scope="col">Comment</th>
  </tr>
  <tr>
   <td>{{SpecName('Service Workers', '#cache-storage', 'CacheStorage')}}</td>
   <td>{{Spec2('Service Workers')}}</td>
   <td>Initial definition.</td>
  </tr>
 </tbody>
</table>

<h2 id="Browser_compatibility">Browser compatibility</h2>

<p>{{Compat("api.CacheStorage.open")}}</p>

<h2 id="See_also">See also</h2>

<ul>
 <li><a href="https://developer.mozilla.org/en-US/docs/Web/API/ServiceWorker_API/Using_Service_Workers">Using Service Workers</a></li>
 <li>{{domxref("Cache")}}</li>
 <li>{{domxref("WorkerGlobalScope.caches")}}</li>
</ul>