github.com/n1ghtfa1l/go-vnt@v0.6.4-alpha.6/swarm/storage/localstore.go (about)

     1  // Copyright 2016 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package storage
    18  
    19  import (
    20  	"encoding/binary"
    21  
    22  	"github.com/vntchain/go-vnt/metrics"
    23  )
    24  
    25  //metrics variables
    26  var (
    27  	dbStorePutCounter = metrics.NewRegisteredCounter("storage.db.dbstore.put.count", nil)
    28  )
    29  
    30  // LocalStore is a combination of inmemory db over a disk persisted db
    31  // implements a Get/Put with fallback (caching) logic using any 2 ChunkStores
    32  type LocalStore struct {
    33  	memStore ChunkStore
    34  	DbStore  ChunkStore
    35  }
    36  
    37  // This constructor uses MemStore and DbStore as components
    38  func NewLocalStore(hash SwarmHasher, params *StoreParams) (*LocalStore, error) {
    39  	dbStore, err := NewDbStore(params.ChunkDbPath, hash, params.DbCapacity, params.Radius)
    40  	if err != nil {
    41  		return nil, err
    42  	}
    43  	return &LocalStore{
    44  		memStore: NewMemStore(dbStore, params.CacheCapacity),
    45  		DbStore:  dbStore,
    46  	}, nil
    47  }
    48  
    49  func (self *LocalStore) CacheCounter() uint64 {
    50  	return uint64(self.memStore.(*MemStore).Counter())
    51  }
    52  
    53  func (self *LocalStore) DbCounter() uint64 {
    54  	return self.DbStore.(*DbStore).Counter()
    55  }
    56  
    57  // LocalStore is itself a chunk store
    58  // unsafe, in that the data is not integrity checked
    59  func (self *LocalStore) Put(chunk *Chunk) {
    60  	chunk.dbStored = make(chan bool)
    61  	self.memStore.Put(chunk)
    62  	if chunk.wg != nil {
    63  		chunk.wg.Add(1)
    64  	}
    65  	go func() {
    66  		dbStorePutCounter.Inc(1)
    67  		self.DbStore.Put(chunk)
    68  		if chunk.wg != nil {
    69  			chunk.wg.Done()
    70  		}
    71  	}()
    72  }
    73  
    74  // Get(chunk *Chunk) looks up a chunk in the local stores
    75  // This method is blocking until the chunk is retrieved
    76  // so additional timeout may be needed to wrap this call if
    77  // ChunkStores are remote and can have long latency
    78  func (self *LocalStore) Get(key Key) (chunk *Chunk, err error) {
    79  	chunk, err = self.memStore.Get(key)
    80  	if err == nil {
    81  		return
    82  	}
    83  	chunk, err = self.DbStore.Get(key)
    84  	if err != nil {
    85  		return
    86  	}
    87  	chunk.Size = int64(binary.LittleEndian.Uint64(chunk.SData[0:8]))
    88  	self.memStore.Put(chunk)
    89  	return
    90  }
    91  
    92  // Close local store
    93  func (self *LocalStore) Close() {}