plugeth/les/odr.go
Felföldi Zsolt 2cdf6ee7e0 light: CHT and bloom trie indexers working in light mode (#16534)
This PR enables the indexers to work in light client mode by
downloading a part of these tries (the Merkle proofs of the last
values of the last known section) in order to be able to add new
values and recalculate subsequent hashes. It also adds CHT data to
NodeInfo.
2018-08-15 22:25:46 +02:00

123 lines
3.4 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 les
import (
"context"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/light"
"github.com/ethereum/go-ethereum/log"
)
// LesOdr implements light.OdrBackend
type LesOdr struct {
db ethdb.Database
chtIndexer, bloomTrieIndexer, bloomIndexer *core.ChainIndexer
retriever *retrieveManager
stop chan struct{}
}
func NewLesOdr(db ethdb.Database, retriever *retrieveManager) *LesOdr {
return &LesOdr{
db: db,
retriever: retriever,
stop: make(chan struct{}),
}
}
// Stop cancels all pending retrievals
func (odr *LesOdr) Stop() {
close(odr.stop)
}
// Database returns the backing database
func (odr *LesOdr) Database() ethdb.Database {
return odr.db
}
// SetIndexers adds the necessary chain indexers to the ODR backend
func (odr *LesOdr) SetIndexers(chtIndexer, bloomTrieIndexer, bloomIndexer *core.ChainIndexer) {
odr.chtIndexer = chtIndexer
odr.bloomTrieIndexer = bloomTrieIndexer
odr.bloomIndexer = bloomIndexer
}
// ChtIndexer returns the CHT chain indexer
func (odr *LesOdr) ChtIndexer() *core.ChainIndexer {
return odr.chtIndexer
}
// BloomTrieIndexer returns the bloom trie chain indexer
func (odr *LesOdr) BloomTrieIndexer() *core.ChainIndexer {
return odr.bloomTrieIndexer
}
// BloomIndexer returns the bloombits chain indexer
func (odr *LesOdr) BloomIndexer() *core.ChainIndexer {
return odr.bloomIndexer
}
const (
MsgBlockBodies = iota
MsgCode
MsgReceipts
MsgProofsV1
MsgProofsV2
MsgHeaderProofs
MsgHelperTrieProofs
)
// Msg encodes a LES message that delivers reply data for a request
type Msg struct {
MsgType int
ReqID uint64
Obj interface{}
}
// Retrieve tries to fetch an object from the LES network.
// If the network retrieval was successful, it stores the object in local db.
func (odr *LesOdr) Retrieve(ctx context.Context, req light.OdrRequest) (err error) {
lreq := LesRequest(req)
reqID := genReqID()
rq := &distReq{
getCost: func(dp distPeer) uint64 {
return lreq.GetCost(dp.(*peer))
},
canSend: func(dp distPeer) bool {
p := dp.(*peer)
return lreq.CanSend(p)
},
request: func(dp distPeer) func() {
p := dp.(*peer)
cost := lreq.GetCost(p)
p.fcServer.QueueRequest(reqID, cost)
return func() { lreq.Request(reqID, p) }
},
}
if err = odr.retriever.retrieve(ctx, reqID, rq, func(p distPeer, msg *Msg) error { return lreq.Validate(odr.db, msg) }, odr.stop); err == nil {
// retrieved from network, store in db
req.StoreResult(odr.db)
} else {
log.Debug("Failed to retrieve data from network", "err", err)
}
return
}