ServiceWorkerContainer.controller

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 controller read-only property of the ServiceWorkerContainer interface returns a ServiceWorker object if its state is activated (the same object returned by ServiceWorkerRegistration.active). This property returns null if the request is a force refresh (Shift + refresh) or if there is no active worker.

Syntax

var myController = navigator.serviceWorker.controller;

Example

if ('serviceWorker' in navigator) {
  navigator.serviceWorker.register('service-worker.js', {scope: './'}).then(function(r) {
    if (navigator.serviceWorker.controller) {
      document.querySelector('#status').textContent = 'A service worker is currently handling network operations.';
    } else {
      document.querySelector('#status').textContent = 'Please reload this page to allow the service worker to handle network operations.';
    }
  }).catch(function(error) {
    document.querySelector('#status').textContent = error;
  });
} else {
  document.querySelector('#status').textContent = 'Service workers are not supported.';
}

Specifications

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

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari (WebKit)
Basic support	40.0	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	?

[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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