The update() method of the ServiceWorkerRegistration interface attempts to update the service worker. It fetches the worker's script URL, and if the new worker is not byte-by-byte identical to the current worker, it installs the new worker. The fetch of the worker bypasses any browser caches if the previous fetch occurred over 24 hours ago.

None.

A Promise that resolves with a ServiceWorkerRegistration object.

The following simple example registers a service worker example then adds an event handler to a button so you can explicitly update the service worker whenever desired:

if ("serviceWorker" in navigator) {
  navigator.serviceWorker
    .register("/sw.js", { scope: "/" })
    .then((registration) => {
      // registration worked
      console.log("Registration succeeded.");
      button.onclick = () => {
        registration.update();
      };
    })
    .catch((error) => {
      // registration failed
      console.error(`Registration failed with ${error}`);
    });
}

• Using Service Workers
• Service workers basic code example
• Is ServiceWorker ready?
• Promise
• Using web workers