getExpiryForUpdate method
Gets the Duration before an updated CacheEntry is considered expired.
This method is called by the caching implementation after a CacheEntry is
updated to determine the Duration before the updated entry expires.
If a Duration.zero is returned a CacheEntry is considered immediately
expired. Returning null
will result in no change to the previously
understood expiry Duration.
Returns the new Duration before an updated entry expires
Implementation
@override
Duration? getExpiryForUpdate() {
// Updating a cache entry has no affect on the current expiry duration
return null;
}