PeriodicSyncEvent

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

Note: This feature is only available in Service Workers.

The PeriodicSyncEvent interface of the Web Periodic Background Synchronization API provides a way to run tasks in the service worker with network connectivity.

An instance of this event is passed to the periodicsync handler. This happens periodically, at an interval greater than or equal to that set in the PeriodicSyncManager.register() method. Other implementation-specific factors such as the user's engagement with the site decide the actual interval.

Constructor

PeriodicSyncEvent() Experimental: Creates a new PeriodicSyncEvent object. This constructor is not typically used. The browser creates these objects itself and provides them to onperiodicsync callback.

Instance properties

Inherits properties from its parent, ExtendableEvent.

PeriodicSyncEvent.tag Read only Experimental: Returns the developer-defined identifier for this PeriodicSyncEvent. Multiple tags can be used by the web app to run different periodic tasks at different frequencies.

Instance methods

Inherits methods from its parent, ExtendableEvent.

Examples

The following example shows how to respond to a periodic sync event in the service worker.

self.addEventListener("periodicsync", (event) => {
  if (event.tag === "get-latest-news") {
    event.waitUntil(fetchAndCacheLatestNews());
  }
});

fetchAndCacheLatestNews is a developer defined function.

Specifications

Specification
Web Periodic Background Synchronization # periodicsync-event

Browser compatibility

Report problems with this compatibility data on GitHub

	desktop					mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on iOS	Samsung Internet	WebView Android	WebView on iOS
`PeriodicSyncEvent` Experimental
`PeriodicSyncEvent()` constructor Experimental
`tag` Experimental

Tip: you can click/tap on a cell for more information.

Full support: Full support
No support: No support
: Experimental. Expect behavior to change in the future.
: See implementation notes.