ServiceWorker.state

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 state read-only property of the ServiceWorker interface returns a string representing the current state of the service worker. It can be one of the following values: installing, installed, activating, activated, or redundant.

Syntax

someURL = ServiceWorker.state 

Value

A ServiceWorkerState definition (see the spec.)

Examples

This code snippet is from the service worker registration-events sample (live demo). The code listens for any change in the ServiceWorker.state and returns its value.

var serviceWorker;
if (registration.installing) {
  serviceWorker = registration.installing;
  document.querySelector('#kind').textContent = 'installing';
} else if (registration.waiting) {
  serviceWorker = registration.waiting;
  document.querySelector('#kind').textContent = 'waiting';
} else if (registration.active) {
  serviceWorker = registration.active;
  document.querySelector('#kind').textContent = 'active';
}

if (serviceWorker) {
  logState(serviceWorker.state);
  serviceWorker.addEventListener('statechange', function(e) {
  logState(e.target.state);
  });
}

Specifications

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

Browser compatibility

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 Android Webview Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support No support No support 44.0 (44.0) (Yes) No support ? No support 40.0

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

Document Tags and Contributors

 Contributors to this page: chrisdavidmills, Sebastianz, fscholz, jpmedley, kscarfone
 Last updated by: chrisdavidmills,