Baseline Widely available
Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
Note: This feature is available in Web Workers.
The match()
method of the CacheStorage
interface checks if a given Request
or URL string is a key for a stored Response
. This method returns a Promise
for a Response
, or a Promise
which resolves to undefined
if no match is found.
You can access CacheStorage
through the Window.caches
property in windows or through the WorkerGlobalScope.caches
property in workers.
Cache
objects are searched in creation order.
Note: caches.match()
is a convenience method. Equivalent functionality is to call cache.match()
on each cache (in the order returned by caches.keys()
) until a Response
is returned.
match(request)
match(request, options)
Parameters
request
The Request
you want to match. This can be a Request
object or a URL string.
options
Optional
An object whose properties control how matching is done in the match
operation. The available options are:
ignoreSearch
A boolean value that specifies whether the matching process should ignore the query string in the URL. For example, if set to true
, the ?value=bar
part of http://foo.com/?value=bar
would be ignored when performing a match. It defaults to false
.
ignoreMethod
A boolean value that, when set to true
, prevents matching operations from validating the Request
http
method (normally only GET
and HEAD
are allowed.) It defaults to false
.
ignoreVary
A boolean value that, when set to true
, tells the matching operation not to perform VARY
header matching. In other words, if the URL matches you will get a match regardless of whether the Response
object has a VARY
header or not. It defaults to false
.
cacheName
A string that represents a specific cache to search within.
a Promise
that resolves to the matching Response
. If no matching response to the specified request is found, the promise resolves with undefined
.
This example is from the MDN simple service worker example (see simple service worker running live). Here we wait for a FetchEvent
to fire. We construct a custom response like so:
CacheStorage
using CacheStorage.match()
. If so, serve that.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()
. The last is necessary because put()
consumes the response body.self.addEventListener("fetch", (event) => {
event.respondWith(
caches.match(event.request).then((response) => {
// caches.match() always resolves
// but in case of success response will have value
if (response !== undefined) {
return response;
}
return fetch(event.request)
.then((response) => {
// response may be used only once
// we need to save clone to put one copy in cache
// and serve second one
let responseClone = response.clone();
caches
.open("v1")
.then((cache) => cache.put(event.request, responseClone));
return response;
})
.catch(() => caches.match("/gallery/myLittleVader.jpg"));
}),
);
});
Specifications Browser compatibility See also
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4