// Value returns an item from the cache and marks it to be kept alive. You can
// pass additional arguments to your DataLoader callback function.
func (table *CacheTable) Value(key interface{}, args ...interface{}) (*CacheItem, error) {
table.RLock()
r, ok := table.items[key]
loadData := table.loadData
table.RUnlock()
if ok {
// Update access counter and timestamp.
r.KeepAlive()
return r, nil
}
// Item doesn't exist in cache. Try and fetch it with a data-loader.
if loadData != nil {
item := loadData(key, args...)
if item != nil {
table.Add(key, item.lifeSpan, item.data)
return item, nil
}
return nil, ErrKeyNotFoundOrLoadable
}
return nil, ErrKeyNotFound
}
