78 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			78 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// Copyright 2016 The go-ethereum Authors
 | 
						|
// This file is part of the go-ethereum library.
 | 
						|
//
 | 
						|
// The go-ethereum library is free software: you can redistribute it and/or modify
 | 
						|
// it under the terms of the GNU Lesser General Public License as published by
 | 
						|
// the Free Software Foundation, either version 3 of the License, or
 | 
						|
// (at your option) any later version.
 | 
						|
//
 | 
						|
// The go-ethereum library is distributed in the hope that it will be useful,
 | 
						|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
 | 
						|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 | 
						|
// GNU Lesser General Public License for more details.
 | 
						|
//
 | 
						|
// You should have received a copy of the GNU Lesser General Public License
 | 
						|
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
 | 
						|
 | 
						|
package storage
 | 
						|
 | 
						|
import (
 | 
						|
	"encoding/binary"
 | 
						|
)
 | 
						|
 | 
						|
// LocalStore is a combination of inmemory db over a disk persisted db
 | 
						|
// implements a Get/Put with fallback (caching) logic using any 2 ChunkStores
 | 
						|
type LocalStore struct {
 | 
						|
	memStore ChunkStore
 | 
						|
	DbStore  ChunkStore
 | 
						|
}
 | 
						|
 | 
						|
// This constructor uses MemStore and DbStore as components
 | 
						|
func NewLocalStore(hash Hasher, params *StoreParams) (*LocalStore, error) {
 | 
						|
	dbStore, err := NewDbStore(params.ChunkDbPath, hash, params.DbCapacity, params.Radius)
 | 
						|
	if err != nil {
 | 
						|
		return nil, err
 | 
						|
	}
 | 
						|
	return &LocalStore{
 | 
						|
		memStore: NewMemStore(dbStore, params.CacheCapacity),
 | 
						|
		DbStore:  dbStore,
 | 
						|
	}, nil
 | 
						|
}
 | 
						|
 | 
						|
// LocalStore is itself a chunk store
 | 
						|
// unsafe, in that the data is not integrity checked
 | 
						|
func (self *LocalStore) Put(chunk *Chunk) {
 | 
						|
	chunk.dbStored = make(chan bool)
 | 
						|
	self.memStore.Put(chunk)
 | 
						|
	if chunk.wg != nil {
 | 
						|
		chunk.wg.Add(1)
 | 
						|
	}
 | 
						|
	go func() {
 | 
						|
		self.DbStore.Put(chunk)
 | 
						|
		if chunk.wg != nil {
 | 
						|
			chunk.wg.Done()
 | 
						|
		}
 | 
						|
	}()
 | 
						|
}
 | 
						|
 | 
						|
// Get(chunk *Chunk) looks up a chunk in the local stores
 | 
						|
// This method is blocking until the chunk is retrieved
 | 
						|
// so additional timeout may be needed to wrap this call if
 | 
						|
// ChunkStores are remote and can have long latency
 | 
						|
func (self *LocalStore) Get(key Key) (chunk *Chunk, err error) {
 | 
						|
	chunk, err = self.memStore.Get(key)
 | 
						|
	if err == nil {
 | 
						|
		return
 | 
						|
	}
 | 
						|
	chunk, err = self.DbStore.Get(key)
 | 
						|
	if err != nil {
 | 
						|
		return
 | 
						|
	}
 | 
						|
	chunk.Size = int64(binary.LittleEndian.Uint64(chunk.SData[0:8]))
 | 
						|
	self.memStore.Put(chunk)
 | 
						|
	return
 | 
						|
}
 | 
						|
 | 
						|
// Close local store
 | 
						|
func (self *LocalStore) Close() {}
 |