SyncManager: register() method

Available in workers

The register() method of the SyncManager interface registers a synchronization event, triggering a sync event inside the associated service worker as soon as network connectivity is available.

Syntax

register(tag)

Parameters

• tag
  • : An identifier for this synchronization event. This will be the value of the tag property of the SyncEvent that gets passed into the service worker’s sync event handler.

Return value

A Promise that resolves to undefined.

Exceptions

• InvalidStateError DOMException
  • : Thrown if current service worker is not active.
• NotAllowedError DOMException
  • : Thrown if background sync has been disabled by the user.

Examples

The following asynchronous function registers a background sync from a browsing context:

async function syncMessagesLater() {
  const registration = await navigator.serviceWorker.ready;
  try {
    await registration.sync.register("sync-messages");
  } catch {
    console.log("Background Sync could not be registered!");
  }
}

Specifications

Browser compatibility