// 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"
"fmt"
"path/filepath"
"sync"
"github.com/ethereum/go-ethereum/metrics"
"github.com/ethereum/go-ethereum/swarm/log"
"github.com/ethereum/go-ethereum/swarm/storage/mock"
)
type LocalStoreParams struct {
*StoreParams
ChunkDbPath string
Validators []ChunkValidator `toml:"-"`
}
func NewDefaultLocalStoreParams() *LocalStoreParams {
return &LocalStoreParams{
StoreParams: NewDefaultStoreParams(),
}
}
//this can only finally be set after all config options (file, cmd line, env vars)
//have been evaluated
func (p *LocalStoreParams) Init(path string) {
if p.ChunkDbPath == "" {
p.ChunkDbPath = filepath.Join(path, "chunks")
}
}
// 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 {
Validators []ChunkValidator
memStore *MemStore
DbStore *LDBStore
mu sync.Mutex
}
// This constructor uses MemStore and DbStore as components
func NewLocalStore(params *LocalStoreParams, mockStore *mock.NodeStore) (*LocalStore, error) {
ldbparams := NewLDBStoreParams(params.StoreParams, params.ChunkDbPath)
dbStore, err := NewMockDbStore(ldbparams, mockStore)
if err != nil {
return nil, err
}
return &LocalStore{
memStore: NewMemStore(params.StoreParams, dbStore),
DbStore: dbStore,
Validators: params.Validators,
}, nil
}
func NewTestLocalStoreForAddr(params *LocalStoreParams) (*LocalStore, error) {
ldbparams := NewLDBStoreParams(params.StoreParams, params.ChunkDbPath)
dbStore, err := NewLDBStore(ldbparams)
if err != nil {
return nil, err
}
localStore := &LocalStore{
memStore: NewMemStore(params.StoreParams, dbStore),
DbStore: dbStore,
Validators: params.Validators,
}
return localStore, nil
}
// Put is responsible for doing validation and storage of the chunk
// by using configured ChunkValidators, MemStore and LDBStore.
// If the chunk is not valid, its GetErrored function will
// return ErrChunkInvalid.
// This method will check if the chunk is already in the MemStore
// and it will return it if it is. If there is an error from
// the MemStore.Get, it will be returned by calling GetErrored
// on the chunk.
// This method is responsible for closing Chunk.ReqC channel
// when the chunk is stored in memstore.
// After the LDBStore.Put, it is ensured that the MemStore
// contains the chunk with the same data, but nil ReqC channel.
func (ls *LocalStore) Put(chunk *Chunk) {
if l := len(chunk.SData); l < 9 {
log.Debug("incomplete chunk data", "addr", chunk.Addr, "length", l)
chunk.SetErrored(ErrChunkInvalid)
chunk.markAsStored()
return
}
valid := true
for _, v := range ls.Validators {
if valid = v.Validate(chunk.Addr, chunk.SData); valid {
break
}
}
if !valid {
log.Trace("invalid content address", "addr", chunk.Addr)
chunk.SetErrored(ErrChunkInvalid)
chunk.markAsStored()
return
}
log.Trace("localstore.put", "addr", chunk.Addr)
ls.mu.Lock()
defer ls.mu.Unlock()
chunk.Size = int64(binary.LittleEndian.Uint64(chunk.SData[0:8]))
memChunk, err := ls.memStore.Get(chunk.Addr)
switch err {
case nil:
if memChunk.ReqC == nil {
chunk.markAsStored()
return
}
case ErrChunkNotFound:
default:
chunk.SetErrored(err)
return
}
ls.DbStore.Put(chunk)
// chunk is no longer a request, but a chunk with data, so replace it in memStore
newc := NewChunk(chunk.Addr, nil)
newc.SData = chunk.SData
newc.Size = chunk.Size
newc.dbStoredC = chunk.dbStoredC
ls.memStore.Put(newc)
if memChunk != nil && memChunk.ReqC != nil {
close(memChunk.ReqC)
}
}
// 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 (ls *LocalStore) Get(addr Address) (chunk *Chunk, err error) {
ls.mu.Lock()
defer ls.mu.Unlock()
return ls.get(addr)
}
func (ls *LocalStore) get(addr Address) (chunk *Chunk, err error) {
chunk, err = ls.memStore.Get(addr)
if err == nil {
if chunk.ReqC != nil {
select {
case <-chunk.ReqC:
default:
metrics.GetOrRegisterCounter("localstore.get.errfetching", nil).Inc(1)
return chunk, ErrFetching
}
}
metrics.GetOrRegisterCounter("localstore.get.cachehit", nil).Inc(1)
return
}
metrics.GetOrRegisterCounter("localstore.get.cachemiss", nil).Inc(1)
chunk, err = ls.DbStore.Get(addr)
if err != nil {
metrics.GetOrRegisterCounter("localstore.get.error", nil).Inc(1)
return
}
chunk.Size = int64(binary.LittleEndian.Uint64(chunk.SData[0:8]))
ls.memStore.Put(chunk)
return
}
// retrieve logic common for local and network chunk retrieval requests
func (ls *LocalStore) GetOrCreateRequest(addr Address) (chunk *Chunk, created bool) {
metrics.GetOrRegisterCounter("localstore.getorcreaterequest", nil).Inc(1)
ls.mu.Lock()
defer ls.mu.Unlock()
var err error
chunk, err = ls.get(addr)
if err == nil && chunk.GetErrored() == nil {
metrics.GetOrRegisterCounter("localstore.getorcreaterequest.hit", nil).Inc(1)
log.Trace(fmt.Sprintf("LocalStore.GetOrRetrieve: %v found locally", addr))
return chunk, false
}
if err == ErrFetching && chunk.GetErrored() == nil {
metrics.GetOrRegisterCounter("localstore.getorcreaterequest.errfetching", nil).Inc(1)
log.Trace(fmt.Sprintf("LocalStore.GetOrRetrieve: %v hit on an existing request %v", addr, chunk.ReqC))
return chunk, false
}
// no data and no request status
metrics.GetOrRegisterCounter("localstore.getorcreaterequest.miss", nil).Inc(1)
log.Trace(fmt.Sprintf("LocalStore.GetOrRetrieve: %v not found locally. open new request", addr))
chunk = NewChunk(addr, make(chan bool))
ls.memStore.Put(chunk)
return chunk, true
}
// RequestsCacheLen returns the current number of outgoing requests stored in the cache
func (ls *LocalStore) RequestsCacheLen() int {
return ls.memStore.requests.Len()
}
// Close the local store
func (ls *LocalStore) Close() {
ls.DbStore.Close()
}