ServiceWorkerGlobalScope.onsync

The ServiceWorkerGlobalScope.onsync event of the ServiceWorkerGlobalScope interface is fired whenever a SyncEvent event occurs. This is triggered when a call to SyncManager.register is made from a service worker client page. The attempt to sync is made either immediately if the network is available or as soon as the network becomes available. 

Syntax

ServiceWorkerGlobalScope.onsync = function(SyncEvent) { ... }
self.addEventListener('sync', function(SyncEvent) { ... })

Specifications

Specification
Web Background Synchronization

Browser compatibility

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