ServiceWorkerContainer.ready

This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The ready read-only property of the ServiceWorkerContainer interface defines whether a service worker is ready to control a page or not. It returns a Promise that will never reject, which resolves to a ServiceWorkerRegistration with an ServiceWorkerRegistration.active worker.

Syntax

navigator.serviceWorker.ready.then(function(serviceWorkerRegistration) { ... });

Example

function subscribe() {
  var subscribeButton = document.querySelector('.js-subscribe-button');
  subscribeButton.disabled = false;
  navigator.serviceWorker.ready.then(function(serviceWorkerRegistration) {
    serviceWorkerRegistration.pushManager.subscribe()
      .then(function(subscription) {
        // The subscription was successful
        subscribeButton.disabled = true;
        return sendSubscriptionToServer(subscription);
      })
      .catch(function(error) {
        if (Notification.permission === 'denied') {
          console.log('Permission for Notifications was denied');
          subscribeButton.disabled = true;
        } else {
          console.log('Unable to subscribe to push.', error);
          subscribeButton.disabled = false;
        }
      });
  });
}

Specifications

Specification	Status	Comment
Service Workers The definition of 'ServiceWorkerRegistration.ready' in that specification.	Working Draft	Initial definition.

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari (WebKit)
Basic support	38.0	44.0 (44.0)^[1]	No support	24	No support

Feature	Android	Firefox Mobile (Gecko)	Firefox OS	IE Mobile	Opera Mobile	Safari Mobile	Chrome for Android
Basic support	?	44.0 (44.0)	(Yes)	No support	?	No support	38.0

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

Syntax

Example

Specifications

Browser compatibility

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