plugeth/les/backend.go
Felix Lange 37dd9086ec core: refactor genesis handling
This commit solves several issues concerning the genesis block:

* Genesis/ChainConfig loading was handled by cmd/geth code. This left
  library users in the cold. They could specify a JSON-encoded
  string and overwrite the config, but didn't get any of the additional
  checks performed by geth.
* Decoding and writing of genesis JSON was conflated in
  WriteGenesisBlock. This made it a lot harder to embed the genesis
  block into the forthcoming config file loader. This commit changes
  things so there is a single Genesis type that represents genesis
  blocks. All uses of Write*Genesis* are changed to use the new type
  instead.
* If the chain config supplied by the user was incompatible with the
  current chain (i.e. the chain had already advanced beyond a scheduled
  fork), it got overwritten. This is not an issue in practice because
  previous forks have always had the highest total difficulty. It might
  matter in the future though. The new code reverts the local chain to
  the point of the fork when upgrading configuration.

The change to genesis block data removes compression library
dependencies from package core.
2017-03-23 15:58:43 +01:00

211 lines
6.8 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 implements the Light Ethereum Subprotocol.
package les
import (
"fmt"
"time"
"github.com/ethereum/go-ethereum/accounts"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/common/compiler"
"github.com/ethereum/go-ethereum/common/hexutil"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/eth"
"github.com/ethereum/go-ethereum/eth/downloader"
"github.com/ethereum/go-ethereum/eth/filters"
"github.com/ethereum/go-ethereum/eth/gasprice"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/event"
"github.com/ethereum/go-ethereum/internal/ethapi"
"github.com/ethereum/go-ethereum/light"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/node"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/params"
"github.com/ethereum/go-ethereum/pow"
rpc "github.com/ethereum/go-ethereum/rpc"
)
type LightEthereum struct {
odr *LesOdr
relay *LesTxRelay
chainConfig *params.ChainConfig
// Channel for shutting down the service
shutdownChan chan bool
// Handlers
txPool *light.TxPool
blockchain *light.LightChain
protocolManager *ProtocolManager
// DB interfaces
chainDb ethdb.Database // Block chain database
ApiBackend *LesApiBackend
eventMux *event.TypeMux
pow pow.PoW
accountManager *accounts.Manager
solcPath string
solc *compiler.Solidity
netVersionId int
netRPCService *ethapi.PublicNetAPI
}
func New(ctx *node.ServiceContext, config *eth.Config) (*LightEthereum, error) {
chainDb, err := eth.CreateDB(ctx, config, "lightchaindata")
if err != nil {
return nil, err
}
chainConfig, genesisHash, genesisErr := core.SetupGenesisBlock(chainDb, config.Genesis)
if _, isCompat := genesisErr.(*params.ConfigCompatError); genesisErr != nil && !isCompat {
return nil, genesisErr
}
log.Info("Initialised chain configuration", "config", chainConfig)
odr := NewLesOdr(chainDb)
relay := NewLesTxRelay()
eth := &LightEthereum{
odr: odr,
relay: relay,
chainDb: chainDb,
chainConfig: chainConfig,
eventMux: ctx.EventMux,
accountManager: ctx.AccountManager,
pow: eth.CreatePoW(ctx, config),
shutdownChan: make(chan bool),
netVersionId: config.NetworkId,
solcPath: config.SolcPath,
}
eth.blockchain, err = light.NewLightChain(odr, eth.chainConfig, eth.pow, eth.eventMux)
if err != nil {
return nil, err
}
// Rewind the chain in case of an incompatible config upgrade.
if compat, ok := genesisErr.(*params.ConfigCompatError); ok {
log.Warn("Rewinding chain to upgrade configuration", "err", compat)
eth.blockchain.SetHead(compat.RewindTo)
core.WriteChainConfig(chainDb, genesisHash, chainConfig)
}
eth.txPool = light.NewTxPool(eth.chainConfig, eth.eventMux, eth.blockchain, eth.relay)
if eth.protocolManager, err = NewProtocolManager(eth.chainConfig, config.LightMode, config.NetworkId, eth.eventMux, eth.pow, eth.blockchain, nil, chainDb, odr, relay); err != nil {
return nil, err
}
relay.ps = eth.protocolManager.peers
relay.reqDist = eth.protocolManager.reqDist
eth.ApiBackend = &LesApiBackend{eth, nil}
eth.ApiBackend.gpo = gasprice.NewLightPriceOracle(eth.ApiBackend)
return eth, nil
}
type LightDummyAPI struct{}
// Etherbase is the address that mining rewards will be send to
func (s *LightDummyAPI) Etherbase() (common.Address, error) {
return common.Address{}, fmt.Errorf("not supported")
}
// Coinbase is the address that mining rewards will be send to (alias for Etherbase)
func (s *LightDummyAPI) Coinbase() (common.Address, error) {
return common.Address{}, fmt.Errorf("not supported")
}
// Hashrate returns the POW hashrate
func (s *LightDummyAPI) Hashrate() hexutil.Uint {
return 0
}
// Mining returns an indication if this node is currently mining.
func (s *LightDummyAPI) Mining() bool {
return false
}
// APIs returns the collection of RPC services the ethereum package offers.
// NOTE, some of these services probably need to be moved to somewhere else.
func (s *LightEthereum) APIs() []rpc.API {
return append(ethapi.GetAPIs(s.ApiBackend, s.solcPath), []rpc.API{
{
Namespace: "eth",
Version: "1.0",
Service: &LightDummyAPI{},
Public: true,
}, {
Namespace: "eth",
Version: "1.0",
Service: downloader.NewPublicDownloaderAPI(s.protocolManager.downloader, s.eventMux),
Public: true,
}, {
Namespace: "eth",
Version: "1.0",
Service: filters.NewPublicFilterAPI(s.ApiBackend, true),
Public: true,
}, {
Namespace: "net",
Version: "1.0",
Service: s.netRPCService,
Public: true,
},
}...)
}
func (s *LightEthereum) ResetWithGenesisBlock(gb *types.Block) {
s.blockchain.ResetWithGenesisBlock(gb)
}
func (s *LightEthereum) BlockChain() *light.LightChain { return s.blockchain }
func (s *LightEthereum) TxPool() *light.TxPool { return s.txPool }
func (s *LightEthereum) LesVersion() int { return int(s.protocolManager.SubProtocols[0].Version) }
func (s *LightEthereum) Downloader() *downloader.Downloader { return s.protocolManager.downloader }
func (s *LightEthereum) EventMux() *event.TypeMux { return s.eventMux }
// Protocols implements node.Service, returning all the currently configured
// network protocols to start.
func (s *LightEthereum) Protocols() []p2p.Protocol {
return s.protocolManager.SubProtocols
}
// Start implements node.Service, starting all internal goroutines needed by the
// Ethereum protocol implementation.
func (s *LightEthereum) Start(srvr *p2p.Server) error {
log.Warn("Light client mode is an experimental feature")
s.netRPCService = ethapi.NewPublicNetAPI(srvr, s.netVersionId)
s.protocolManager.Start(srvr)
return nil
}
// Stop implements node.Service, terminating all internal goroutines used by the
// Ethereum protocol.
func (s *LightEthereum) Stop() error {
s.odr.Stop()
s.blockchain.Stop()
s.protocolManager.Stop()
s.txPool.Stop()
s.eventMux.Stop()
time.Sleep(time.Millisecond * 200)
s.chainDb.Close()
close(s.shutdownChan)
return nil
}