BackgroundFetchManager
        
        
          Limited availability
        
        
        
          
                
              
                
              
                
              
        
        
      
      This feature is not Baseline because it does not work in some of the most widely-used browsers.
Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
Note: This feature is available in Web Workers.
The BackgroundFetchManager interface of the Background Fetch API is a map where the keys are background fetch IDs and the values are BackgroundFetchRegistration objects.
Instance properties
None.
Instance methods
fetch()Experimental- 
Returns a
Promisethat resolves with aBackgroundFetchRegistrationobject for a supplied array of URLs andRequestobjects. get()Experimental- 
Returns a
Promisethat resolves with theBackgroundFetchRegistrationassociated with the providedidorundefinedif theidis not found. getIds()Experimental- 
Returns the IDs of all registered background fetches.
 
Examples
The example below shows how to get an instance of BackgroundFetchManager from a ServiceWorkerRegistration object and calls fetch() to download an audio file in the background.
navigator.serviceWorker.ready.then(async (swReg) => {
  const bgFetch = await swReg.backgroundFetch.fetch(
    "my-fetch",
    ["/ep-5.mp3", "ep-5-artwork.jpg"],
    {
      title: "Episode 5: Interesting things.",
      icons: [
        {
          sizes: "300x300",
          src: "/ep-5-icon.png",
          type: "image/png",
        },
      ],
      downloadTotal: 60 * 1024 * 1024,
    },
  );
});
Specifications
| Specification | 
|---|
| Background Fetch> # background-fetch-manager>  | 
            
Browser compatibility
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