The delete() method of the CacheStorage interface finds the Cache object matching the cacheName, and if found, deletes the Cache object and returns a Promise that resolves to true. If no Cache object is found, it resolves to false.

You can access CacheStorage through the global caches property.

cacheName

The name of the cache you want to delete.

a Promise that resolves to true if the Cache object is found and deleted, and false otherwise.

In this code snippet we wait for an activate event, and then run a waitUntil() block that clears up any old, unused caches before a new service worker is activated. Here we have an array of cache names we want to keep (cachesToKeep). We return the keys of the caches in the CacheStorage object using CacheStorage.keys, then check each key to see if it is in the array. If not, we delete it using delete().

this.addEventListener("activate", (event) => {
  const cachesToKeep = ["v2"];

  event.waitUntil(
    caches.keys().then((keyList) =>
      Promise.all(
        keyList.map((key) => {
          if (!cachesToKeep.includes(key)) {
            return caches.delete(key);
          }
        }),
      ),
    ),
  );
});

• Using Service Workers
• Cache
• caches