ContentIndex: add() method

The service worker's registration is not present or the service worker does not contain aFetchEvent.
One ofid,title,description orurl parameter are missing, not of typeString, or an emptyString.
Theurl parameter is notsame-origin policy with theservice worker.
One of the items inicons are not an image type, or fetching one of the items inicons failed with a network error or decode error.

Examples

Here we're declaring an item in the correct format and creating an asynchronousfunction which uses theadd method to register it with thecontent index.

// our contentconst item = {  id: "post-1",  url: "/posts/amet.html",  title: "Amet consectetur adipisicing",  description:    "Repellat et quia iste possimus ducimus aliquid a aut eaque nostrum.",  icons: [    {      src: "/media/dark.png",      sizes: "128x128",      type: "image/png",    },  ],  category: "article",};// our asynchronous function to add indexed contentasync function registerContent(data) {  const registration = await navigator.serviceWorker.ready;  // feature detect Content Index  if (!registration.index) {    return;  }  // register content  try {    await registration.index.add(data);  } catch (e) {    console.log("Failed to register content: ", e.message);  }}

Theadd method can also be used within theservice worker scope.

// our contentconst item = {  id: "post-1",  url: "/posts/amet.html",  title: "Amet consectetur adipisicing",  description:    "Repellat et quia iste possimus ducimus aliquid a aut eaque nostrum.",  icons: [    {      src: "/media/dark.png",      sizes: "128x128",      type: "image/png",    },  ],  category: "article",};self.registration.index.add(item);