package trie type Backend interface { Get([]byte) ([]byte, error) Put([]byte, []byte) } type Cache struct { store map[string][]byte backend Backend } func NewCache(backend Backend) *Cache { return &Cache{make(map[string][]byte), backend} } func (self *Cache) Get(key []byte) []byte { data := self.store[string(key)] if data == nil { data, _ = self.backend.Get(key) } return data } func (self *Cache) Put(key []byte, data []byte) { self.store[string(key)] = data } func (self *Cache) Flush() { for k, v := range self.store { self.backend.Put([]byte(k), v) } // This will eventually grow too large. We'd could // do a make limit on storage and push out not-so-popular nodes. //self.Reset() } func (self *Cache) Reset() { self.store = make(map[string][]byte) }