ServiceWorkerGlobalScope

ServiceWorkerGlobalScope interface of the Service Worker API represents the global execution context of a service worker.

Developers should keep in mind that the ServiceWorker state is not persisted across the termination/restart cycle, so each event handler should assume it's being invoked with a bare, default global state.

Once successfully registered, a service worker can and will be terminated when idle to conserve memory and processor power. An active service worker is automatically restarted to respond to events, such as ServiceWorkerGlobalScope.onfetch or ServiceWorkerGlobalScope.onmessage .

Additionally, synchronous requests are not allowed from within a service worker — only asynchronous requests, like those initiated via the fetch() method, can be used.

This interface inherits from the WorkerGlobalScope interface, and its parent EventTarget , and therefore implements properties from WindowTimers , WindowBase64 ,和 WindowEventHandlers .

特性

ServiceWorkerGlobalScope.caches 只读
Contains the CacheStorage object associated with the service worker.
ServiceWorkerGlobalScope.clients 只读
Contains the Clients object associated with the service worker.
ServiceWorkerGlobalScope.registration 只读
Contains the ServiceWorkerRegistration object that represents the service worker's registration.

Events

activate
Occurs when a ServiceWorkerRegistration acquires a new ServiceWorkerRegistration.active worker.
Also available via the ServiceWorkerGlobalScope.onactivate 特性。
contentdelete
Occurs when an item is removed from the Content Index .
Also available via the ServiceWorkerGlobalScope.oncontentdelete 特性。
fetch
Occurs when a fetch() 被调用。
Also available via the ServiceWorkerGlobalScope.onfetch 特性。
安装
Occurs when a ServiceWorkerRegistration acquires a new ServiceWorkerRegistration.installing worker.
Also available via the ServiceWorkerGlobalScope.oninstall 特性。
message
Occurs when incoming messages are received. Controlled pages can use the MessagePort.postMessage() method to send messages to service workers. The service worker can optionally send a response back via the MessagePort exposed in event.data.port , corresponding to the controlled page.
Also available via the ServiceWorkerGlobalScope.onmessage 特性。
notificationclick
Occurs when a user clicks on a displayed notification.
Also available via the ServiceWorkerGlobalScope.onnotificationclick 特性。
notificationclose
Occurs — when a user closes a displayed notification.
Also available via the ServiceWorkerGlobalScope.onnotificationclose 特性。
push
Occurs when a server push notification is received.
Also available via the ServiceWorkerGlobalScope.onpush 特性。
pushsubscriptionchange
Occurs when a push subscription has been invalidated, or is about to be invalidated (e.g. when a push service sets an expiration time).
Also available via the ServiceWorkerGlobalScope.onpushsubscriptionchange 特性。
sync
Triggered when a call to SyncManager.register is made from a service worker client page. The attempt to sync is made either immediately if the network is available or as soon as the network becomes available.
Also available via the ServiceWorkerGlobalScope.onsync 特性。

方法

ServiceWorkerGlobalScope.skipWaiting()
Allows the current service worker registration to progress from waiting to active state while service worker clients are using it.

ServiceWorkerGlobalScope implements WorkerGlobalScope — which implements WindowOrWorkerGlobalScope . Therefore it also has the following property available to it:

GlobalFetch.fetch()
Starts the process of fetching a resource. This returns a promise that resolves to the Response object representing the response to your request. This algorithm is the entry point for the fetch handling handed to the service worker context.

范例

This code snippet is from the service worker prefetch sample (见 prefetch example live .) The ServiceWorkerGlobalScope.onfetch event handler listens for the fetch event. When fired, the code returns a promise that resolves to the first matching request in the Cache object. If no match is found, the code fetches a response from the network.

The code also handles exceptions thrown from the fetch() operation. Note that an HTTP error response (e.g., 404) will not trigger an exception. It will return a normal response object that has the appropriate error code set.

self.addEventListener('fetch', function(event) {
  console.log('Handling fetch event for', event.request.url);
  event.respondWith(
    caches.match(event.request).then(function(response) {
      if (response) {
        console.log('Found response in cache:', response);
        return response;
      }
      console.log('No response found in cache. About to fetch from network...');
      return fetch(event.request).then(function(response) {
        console.log('Response from network is:', response);
        return response;
      }, function(error) {
        console.error('Fetching failed:', error);
        throw error;
      });
    })
  );
});
					

规范

规范 状态 Comment
服务工作者
The definition of 'ServiceWorkerGlobalScope' in that specification.
工作草案 初始定义

浏览器兼容性

更新 GitHub 上的兼容性数据
Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
ServiceWorkerGlobalScope Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
activate event
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
caches
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
clients
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
安装 event
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
message event
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
notificationclick event Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android No Chrome Android 40 Firefox Android 44 Opera Android 27 Safari iOS 11.3 Samsung Internet Android 4.0
onabortpayment
Chrome 61
Disabled
61
Disabled
Disabled From version 61: this feature is behind the #service-worker-payment-apps preference (needs to be set to Enabled ). To change preferences in Chrome, visit chrome://flags.
Edge ≤79
Disabled
≤79
Disabled
Disabled From version ≤79: this feature is behind the #service-worker-payment-apps preference (needs to be set to Enabled ).
Firefox ? IE No Opera ? Safari 11.1 WebView Android No Chrome Android 61
Disabled
61
Disabled
Disabled From version 61: this feature is behind the #service-worker-payment-apps preference (needs to be set to Enabled ). To change preferences in Chrome, visit chrome://flags.
Firefox Android ? Opera Android ? Safari iOS 11.3 Samsung Internet Android No
onactivate
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
onbackgroundfetchabort
Chrome 74 Edge No Firefox No IE No Opera 62 Safari No WebView Android No Chrome Android 74 Firefox Android No Opera Android 53 Safari iOS No Samsung Internet Android 11.0
onbackgroundfetchclick
Chrome 74 Edge No Firefox No IE No Opera 62 Safari No WebView Android No Chrome Android 74 Firefox Android No Opera Android 53 Safari iOS No Samsung Internet Android 11.0
onbackgroundfetchfail
Chrome 74 Edge No Firefox No IE No Opera 62 Safari No WebView Android No Chrome Android 74 Firefox Android No Opera Android 53 Safari iOS No Samsung Internet Android 11.0
onbackgroundfetchsuccess
Chrome 74 Edge No Firefox No IE No Opera 62 Safari No WebView Android No Chrome Android 74 Firefox Android No Opera Android 53 Safari iOS No Samsung Internet Android 11.0
oncanmakepayment
Chrome 61
Disabled
61
Disabled
Disabled From version 61: this feature is behind the #service-worker-payment-apps preference (needs to be set to Enabled ). To change preferences in Chrome, visit chrome://flags.
Edge ≤79
Disabled
≤79
Disabled
Disabled From version ≤79: this feature is behind the #service-worker-payment-apps preference (needs to be set to Enabled ).
Firefox ? IE No Opera ? Safari ? WebView Android No Chrome Android 61
Disabled
61
Disabled
Disabled From version 61: this feature is behind the #service-worker-payment-apps preference (needs to be set to Enabled ). To change preferences in Chrome, visit chrome://flags.
Firefox Android ? Opera Android ? Safari iOS ? Samsung Internet Android No
onfetch
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
oninstall
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
onmessage
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
onmessageerror Chrome ? Edge ? Firefox ? IE No Opera ? Safari ? WebView Android ? Chrome Android ? Firefox Android ? Opera Android ? Safari iOS ? Samsung Internet Android ?
onnotificationclick
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
onnotificationclose
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
onpaymentrequest
Chrome 57
Disabled
57
Disabled
Disabled From version 57: this feature is behind the #service-worker-payment-apps preference (needs to be set to Enabled ). To change preferences in Chrome, visit chrome://flags.
Edge ≤79
Disabled
≤79
Disabled
Disabled From version ≤79: this feature is behind the #service-worker-payment-apps preference (needs to be set to Enabled ).
Firefox ? IE No Opera ? Safari ? WebView Android No Chrome Android 57
Disabled
57
Disabled
Disabled From version 57: this feature is behind the #service-worker-payment-apps preference (needs to be set to Enabled ). To change preferences in Chrome, visit chrome://flags.
Firefox Android ? Opera Android ? Safari iOS ? Samsung Internet Android No
onpush
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
onpushsubscriptionchange
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
onsync
Chrome 49 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 49 Chrome Android 49 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 5.0
push event Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
pushsubscriptionchange event Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
registration
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari 11.1 WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS 11.3 Samsung Internet Android 4.0
skipWaiting
Chrome 40 Edge ≤79 Firefox 44
44
Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No Opera 24 Safari No WebView Android 40 Chrome Android 40 Firefox Android 44 Opera Android 24 Safari iOS No Samsung Internet Android 4.0

图例

完整支持
完整支持
不支持
不支持
兼容性未知
兼容性未知
实验。期望将来行为有所改变。
实验。期望将来行为有所改变。
见实现注意事项。
用户必须明确启用此特征。
用户必须明确启用此特征。

另请参阅