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package node
import (
"bytes"
"context"
"errors"
"fmt"
"net"
"net/http"
"github.com/prometheus/client_golang/prometheus/promhttp"
abci "github.com/tendermint/tendermint/abci/types"
amino "github.com/tendermint/go-amino"
cmn "github.com/tendermint/tmlibs/common"
dbm "github.com/tendermint/tmlibs/db"
"github.com/tendermint/tmlibs/log"
bc "github.com/tendermint/tendermint/blockchain"
cfg "github.com/tendermint/tendermint/config"
cs "github.com/tendermint/tendermint/consensus"
"github.com/tendermint/tendermint/crypto"
"github.com/tendermint/tendermint/evidence"
mempl "github.com/tendermint/tendermint/mempool"
"github.com/tendermint/tendermint/p2p"
"github.com/tendermint/tendermint/p2p/pex"
"github.com/tendermint/tendermint/privval"
"github.com/tendermint/tendermint/proxy"
rpccore "github.com/tendermint/tendermint/rpc/core"
ctypes "github.com/tendermint/tendermint/rpc/core/types"
grpccore "github.com/tendermint/tendermint/rpc/grpc"
rpc "github.com/tendermint/tendermint/rpc/lib"
rpcserver "github.com/tendermint/tendermint/rpc/lib/server"
sm "github.com/tendermint/tendermint/state"
"github.com/tendermint/tendermint/state/txindex"
"github.com/tendermint/tendermint/state/txindex/kv"
"github.com/tendermint/tendermint/state/txindex/null"
"github.com/tendermint/tendermint/types"
"github.com/tendermint/tendermint/version"
_ "net/http/pprof"
)
//------------------------------------------------------------------------------
// DBContext specifies config information for loading a new DB.
type DBContext struct {
ID string
Config *cfg.Config
}
// DBProvider takes a DBContext and returns an instantiated DB.
type DBProvider func(*DBContext) (dbm.DB, error)
// DefaultDBProvider returns a database using the DBBackend and DBDir
// specified in the ctx.Config.
func DefaultDBProvider(ctx *DBContext) (dbm.DB, error) {
dbType := dbm.DBBackendType(ctx.Config.DBBackend)
return dbm.NewDB(ctx.ID, dbType, ctx.Config.DBDir()), nil
}
// GenesisDocProvider returns a GenesisDoc.
// It allows the GenesisDoc to be pulled from sources other than the
// filesystem, for instance from a distributed key-value store cluster.
type GenesisDocProvider func() (*types.GenesisDoc, error)
// DefaultGenesisDocProviderFunc returns a GenesisDocProvider that loads
// the GenesisDoc from the config.GenesisFile() on the filesystem.
func DefaultGenesisDocProviderFunc(config *cfg.Config) GenesisDocProvider {
return func() (*types.GenesisDoc, error) {
return types.GenesisDocFromFile(config.GenesisFile())
}
}
// NodeProvider takes a config and a logger and returns a ready to go Node.
type NodeProvider func(*cfg.Config, log.Logger) (*Node, error)
// DefaultNewNode returns a Tendermint node with default settings for the
// PrivValidator, ClientCreator, GenesisDoc, and DBProvider.
// It implements NodeProvider.
func DefaultNewNode(config *cfg.Config, logger log.Logger) (*Node, error) {
return NewNode(config,
privval.LoadOrGenFilePV(config.PrivValidatorFile()),
proxy.DefaultClientCreator(config.ProxyApp, config.ABCI, config.DBDir()),
DefaultGenesisDocProviderFunc(config),
DefaultDBProvider,
DefaultMetricsProvider,
logger,
)
}
// MetricsProvider returns a consensus, p2p and mempool Metrics.
type MetricsProvider func() (*cs.Metrics, *p2p.Metrics, *mempl.Metrics)
// DefaultMetricsProvider returns consensus, p2p and mempool Metrics build
// using Prometheus client library.
func DefaultMetricsProvider() (*cs.Metrics, *p2p.Metrics, *mempl.Metrics) {
return cs.PrometheusMetrics(), p2p.PrometheusMetrics(), mempl.PrometheusMetrics()
}
// NopMetricsProvider returns consensus, p2p and mempool Metrics as no-op.
func NopMetricsProvider() (*cs.Metrics, *p2p.Metrics, *mempl.Metrics) {
return cs.NopMetrics(), p2p.NopMetrics(), mempl.NopMetrics()
}
//------------------------------------------------------------------------------
// Node is the highest level interface to a full Tendermint node.
// It includes all configuration information and running services.
type Node struct {
cmn.BaseService
// config
config *cfg.Config
genesisDoc *types.GenesisDoc // initial validator set
privValidator types.PrivValidator // local node's validator key
// network
sw *p2p.Switch // p2p connections
addrBook pex.AddrBook // known peers
// services
eventBus *types.EventBus // pub/sub for services
stateDB dbm.DB
blockStore *bc.BlockStore // store the blockchain to disk
bcReactor *bc.BlockchainReactor // for fast-syncing
mempoolReactor *mempl.MempoolReactor // for gossipping transactions
consensusState *cs.ConsensusState // latest consensus state
consensusReactor *cs.ConsensusReactor // for participating in the consensus
evidencePool *evidence.EvidencePool // tracking evidence
proxyApp proxy.AppConns // connection to the application
rpcListeners []net.Listener // rpc servers
txIndexer txindex.TxIndexer
indexerService *txindex.IndexerService
prometheusSrv *http.Server
}
// NewNode returns a new, ready to go, Tendermint Node.
func NewNode(config *cfg.Config,
privValidator types.PrivValidator,
clientCreator proxy.ClientCreator,
genesisDocProvider GenesisDocProvider,
dbProvider DBProvider,
metricsProvider MetricsProvider,
logger log.Logger) (*Node, error) {
// Get BlockStore
blockStoreDB, err := dbProvider(&DBContext{"blockstore", config})
if err != nil {
return nil, err
}
blockStore := bc.NewBlockStore(blockStoreDB)
// Get State
stateDB, err := dbProvider(&DBContext{"state", config})
if err != nil {
return nil, err
}
// Get genesis doc
// TODO: move to state package?
genDoc, err := loadGenesisDoc(stateDB)
if err != nil {
genDoc, err = genesisDocProvider()
if err != nil {
return nil, err
}
// save genesis doc to prevent a certain class of user errors (e.g. when it
// was changed, accidentally or not). Also good for audit trail.
saveGenesisDoc(stateDB, genDoc)
}
state, err := sm.LoadStateFromDBOrGenesisDoc(stateDB, genDoc)
if err != nil {
return nil, err
}
// Create the proxyApp, which manages connections (consensus, mempool, query)
// and sync tendermint and the app by performing a handshake
// and replaying any necessary blocks
consensusLogger := logger.With("module", "consensus")
handshaker := cs.NewHandshaker(stateDB, state, blockStore, genDoc)
handshaker.SetLogger(consensusLogger)
proxyApp := proxy.NewAppConns(clientCreator, handshaker)
proxyApp.SetLogger(logger.With("module", "proxy"))
if err := proxyApp.Start(); err != nil {
return nil, fmt.Errorf("Error starting proxy app connections: %v", err)
}
// reload the state (it may have been updated by the handshake)
state = sm.LoadState(stateDB)
// If an address is provided, listen on the socket for a
// connection from an external signing process.
if config.PrivValidatorListenAddr != "" {
var (
// TODO: persist this key so external signer
// can actually authenticate us
privKey = crypto.GenPrivKeyEd25519()
pvsc = privval.NewSocketPV(
logger.With("module", "privval"),
config.PrivValidatorListenAddr,
privKey,
)
)
if err := pvsc.Start(); err != nil {
return nil, fmt.Errorf("Error starting private validator client: %v", err)
}
privValidator = pvsc
}
// Decide whether to fast-sync or not
// We don't fast-sync when the only validator is us.
fastSync := config.FastSync
if state.Validators.Size() == 1 {
addr, _ := state.Validators.GetByIndex(0)
if bytes.Equal(privValidator.GetAddress(), addr) {
fastSync = false
}
}
// Log whether this node is a validator or an observer
if state.Validators.HasAddress(privValidator.GetAddress()) {
consensusLogger.Info("This node is a validator", "addr", privValidator.GetAddress(), "pubKey", privValidator.GetPubKey())
} else {
consensusLogger.Info("This node is not a validator", "addr", privValidator.GetAddress(), "pubKey", privValidator.GetPubKey())
}
// metrics
var (
csMetrics *cs.Metrics
p2pMetrics *p2p.Metrics
memplMetrics *mempl.Metrics
)
if config.Instrumentation.Prometheus {
csMetrics, p2pMetrics, memplMetrics = metricsProvider()
} else {
csMetrics, p2pMetrics, memplMetrics = NopMetricsProvider()
}
// Make MempoolReactor
mempoolLogger := logger.With("module", "mempool")
mempool := mempl.NewMempool(
config.Mempool,
proxyApp.Mempool(),
state.LastBlockHeight,
mempl.WithMetrics(memplMetrics),
)
mempool.SetLogger(mempoolLogger)
mempool.InitWAL() // no need to have the mempool wal during tests
mempoolReactor := mempl.NewMempoolReactor(config.Mempool, mempool)
mempoolReactor.SetLogger(mempoolLogger)
if config.Consensus.WaitForTxs() {
mempool.EnableTxsAvailable()
}
// Make Evidence Reactor
evidenceDB, err := dbProvider(&DBContext{"evidence", config})
if err != nil {
return nil, err
}
evidenceLogger := logger.With("module", "evidence")
evidenceStore := evidence.NewEvidenceStore(evidenceDB)
evidencePool := evidence.NewEvidencePool(stateDB, evidenceStore)
evidencePool.SetLogger(evidenceLogger)
evidenceReactor := evidence.NewEvidenceReactor(evidencePool)
evidenceReactor.SetLogger(evidenceLogger)
blockExecLogger := logger.With("module", "state")
// make block executor for consensus and blockchain reactors to execute blocks
blockExec := sm.NewBlockExecutor(stateDB, blockExecLogger, proxyApp.Consensus(), mempool, evidencePool)
// Make BlockchainReactor
bcReactor := bc.NewBlockchainReactor(state.Copy(), blockExec, blockStore, fastSync)
bcReactor.SetLogger(logger.With("module", "blockchain"))
// Make ConsensusReactor
consensusState := cs.NewConsensusState(
config.Consensus,
state.Copy(),
blockExec,
blockStore,
mempool,
evidencePool,
cs.WithMetrics(csMetrics),
)
consensusState.SetLogger(consensusLogger)
if privValidator != nil {
consensusState.SetPrivValidator(privValidator)
}
consensusReactor := cs.NewConsensusReactor(consensusState, fastSync)
consensusReactor.SetLogger(consensusLogger)
p2pLogger := logger.With("module", "p2p")
sw := p2p.NewSwitch(config.P2P, p2p.WithMetrics(p2pMetrics))
sw.SetLogger(p2pLogger)
sw.AddReactor("MEMPOOL", mempoolReactor)
sw.AddReactor("BLOCKCHAIN", bcReactor)
sw.AddReactor("CONSENSUS", consensusReactor)
sw.AddReactor("EVIDENCE", evidenceReactor)
// Optionally, start the pex reactor
//
// TODO:
//
// We need to set Seeds and PersistentPeers on the switch,
// since it needs to be able to use these (and their DNS names)
// even if the PEX is off. We can include the DNS name in the NetAddress,
// but it would still be nice to have a clear list of the current "PersistentPeers"
// somewhere that we can return with net_info.
//
// If PEX is on, it should handle dialing the seeds. Otherwise the switch does it.
// Note we currently use the addrBook regardless at least for AddOurAddress
addrBook := pex.NewAddrBook(config.P2P.AddrBookFile(), config.P2P.AddrBookStrict)
addrBook.SetLogger(p2pLogger.With("book", config.P2P.AddrBookFile()))
if config.P2P.PexReactor {
// TODO persistent peers ? so we can have their DNS addrs saved
pexReactor := pex.NewPEXReactor(addrBook,
&pex.PEXReactorConfig{
Seeds: cmn.SplitAndTrim(config.P2P.Seeds, ",", " "),
SeedMode: config.P2P.SeedMode,
PrivatePeerIDs: cmn.SplitAndTrim(config.P2P.PrivatePeerIDs, ",", " ")})
pexReactor.SetLogger(p2pLogger)
sw.AddReactor("PEX", pexReactor)
}
sw.SetAddrBook(addrBook)
// Filter peers by addr or pubkey with an ABCI query.
// If the query return code is OK, add peer.
// XXX: Query format subject to change
if config.FilterPeers {
// NOTE: addr is ip:port
sw.SetAddrFilter(func(addr net.Addr) error {
resQuery, err := proxyApp.Query().QuerySync(abci.RequestQuery{Path: cmn.Fmt("/p2p/filter/addr/%s", addr.String())})
if err != nil {
return err
}
if resQuery.IsErr() {
return fmt.Errorf("Error querying abci app: %v", resQuery)
}
return nil
})
sw.SetIDFilter(func(id p2p.ID) error {
resQuery, err := proxyApp.Query().QuerySync(abci.RequestQuery{Path: cmn.Fmt("/p2p/filter/id/%s", id)})
if err != nil {
return err
}
if resQuery.IsErr() {
return fmt.Errorf("Error querying abci app: %v", resQuery)
}
return nil
})
}
eventBus := types.NewEventBus()
eventBus.SetLogger(logger.With("module", "events"))
// services which will be publishing and/or subscribing for messages (events)
// consensusReactor will set it on consensusState and blockExecutor
consensusReactor.SetEventBus(eventBus)
// Transaction indexing
var txIndexer txindex.TxIndexer
switch config.TxIndex.Indexer {
case "kv":
store, err := dbProvider(&DBContext{"tx_index", config})
if err != nil {
return nil, err
}
if config.TxIndex.IndexTags != "" {
txIndexer = kv.NewTxIndex(store, kv.IndexTags(cmn.SplitAndTrim(config.TxIndex.IndexTags, ",", " ")))
} else if config.TxIndex.IndexAllTags {
txIndexer = kv.NewTxIndex(store, kv.IndexAllTags())
} else {
txIndexer = kv.NewTxIndex(store)
}
default:
txIndexer = &null.TxIndex{}
}
indexerService := txindex.NewIndexerService(txIndexer, eventBus)
indexerService.SetLogger(logger.With("module", "txindex"))
// run the profile server
profileHost := config.ProfListenAddress
if profileHost != "" {
go func() {
logger.Error("Profile server", "err", http.ListenAndServe(profileHost, nil))
}()
}
node := &Node{
config: config,
genesisDoc: genDoc,
privValidator: privValidator,
sw: sw,
addrBook: addrBook,
stateDB: stateDB,
blockStore: blockStore,
bcReactor: bcReactor,
mempoolReactor: mempoolReactor,
consensusState: consensusState,
consensusReactor: consensusReactor,
evidencePool: evidencePool,
proxyApp: proxyApp,
txIndexer: txIndexer,
indexerService: indexerService,
eventBus: eventBus,
}
node.BaseService = *cmn.NewBaseService(logger, "Node", node)
return node, nil
}
// OnStart starts the Node. It implements cmn.Service.
func (n *Node) OnStart() error {
err := n.eventBus.Start()
if err != nil {
return err
}
// Create & add listener
protocol, address := cmn.ProtocolAndAddress(n.config.P2P.ListenAddress)
l := p2p.NewDefaultListener(protocol, address, n.config.P2P.SkipUPNP, n.Logger.With("module", "p2p"))
n.sw.AddListener(l)
// Generate node PrivKey
// TODO: pass in like privValidator
nodeKey, err := p2p.LoadOrGenNodeKey(n.config.NodeKeyFile())
if err != nil {
return err
}
n.Logger.Info("P2P Node ID", "ID", nodeKey.ID(), "file", n.config.NodeKeyFile())
nodeInfo := n.makeNodeInfo(nodeKey.ID())
n.sw.SetNodeInfo(nodeInfo)
n.sw.SetNodeKey(nodeKey)
// Add ourselves to addrbook to prevent dialing ourselves
n.addrBook.AddOurAddress(nodeInfo.NetAddress())
// Start the RPC server before the P2P server
// so we can eg. receive txs for the first block
if n.config.RPC.ListenAddress != "" {
listeners, err := n.startRPC()
if err != nil {
return err
}
n.rpcListeners = listeners
}
if n.config.Instrumentation.Prometheus {
n.prometheusSrv = n.startPrometheusServer(n.config.Instrumentation.PrometheusListenAddr)
}
// Start the switch (the P2P server).
err = n.sw.Start()
if err != nil {
return err
}
// Always connect to persistent peers
if n.config.P2P.PersistentPeers != "" {
err = n.sw.DialPeersAsync(n.addrBook, cmn.SplitAndTrim(n.config.P2P.PersistentPeers, ",", " "), true)
if err != nil {
return err
}
}
// start tx indexer
return n.indexerService.Start()
}
// OnStop stops the Node. It implements cmn.Service.
func (n *Node) OnStop() {
n.BaseService.OnStop()
n.Logger.Info("Stopping Node")
// TODO: gracefully disconnect from peers.
n.sw.Stop()
for _, l := range n.rpcListeners {
n.Logger.Info("Closing rpc listener", "listener", l)
if err := l.Close(); err != nil {
n.Logger.Error("Error closing listener", "listener", l, "err", err)
}
}
n.eventBus.Stop()
n.indexerService.Stop()
if pvsc, ok := n.privValidator.(*privval.SocketPV); ok {
if err := pvsc.Stop(); err != nil {
n.Logger.Error("Error stopping priv validator socket client", "err", err)
}
}
if n.prometheusSrv != nil {
if err := n.prometheusSrv.Shutdown(context.Background()); err != nil {
// Error from closing listeners, or context timeout:
n.Logger.Error("Prometheus HTTP server Shutdown", "err", err)
}
}
}
// RunForever waits for an interrupt signal and stops the node.
func (n *Node) RunForever() {
// Sleep forever and then...
cmn.TrapSignal(func() {
n.Stop()
})
}
// AddListener adds a listener to accept inbound peer connections.
// It should be called before starting the Node.
// The first listener is the primary listener (in NodeInfo)
func (n *Node) AddListener(l p2p.Listener) {
n.sw.AddListener(l)
}
// ConfigureRPC sets all variables in rpccore so they will serve
// rpc calls from this node
func (n *Node) ConfigureRPC() {
rpccore.SetStateDB(n.stateDB)
rpccore.SetBlockStore(n.blockStore)
rpccore.SetConsensusState(n.consensusState)
rpccore.SetMempool(n.mempoolReactor.Mempool)
rpccore.SetEvidencePool(n.evidencePool)
rpccore.SetSwitch(n.sw)
rpccore.SetPubKey(n.privValidator.GetPubKey())
rpccore.SetGenesisDoc(n.genesisDoc)
rpccore.SetAddrBook(n.addrBook)
rpccore.SetProxyAppQuery(n.proxyApp.Query())
rpccore.SetTxIndexer(n.txIndexer)
rpccore.SetConsensusReactor(n.consensusReactor)
rpccore.SetEventBus(n.eventBus)
rpccore.SetLogger(n.Logger.With("module", "rpc"))
}
func (n *Node) startRPC() ([]net.Listener, error) {
n.ConfigureRPC()
listenAddrs := cmn.SplitAndTrim(n.config.RPC.ListenAddress, ",", " ")
coreCodec := amino.NewCodec()
ctypes.RegisterAmino(coreCodec)
if n.config.RPC.Unsafe {
rpccore.AddUnsafeRoutes()
}
// we may expose the rpc over both a unix and tcp socket
listeners := make([]net.Listener, len(listenAddrs))
for i, listenAddr := range listenAddrs {
mux := http.NewServeMux()
rpcLogger := n.Logger.With("module", "rpc-server")
wm := rpcserver.NewWebsocketManager(rpccore.Routes, coreCodec, rpcserver.EventSubscriber(n.eventBus))
wm.SetLogger(rpcLogger.With("protocol", "websocket"))
mux.HandleFunc("/websocket", wm.WebsocketHandler)
rpcserver.RegisterRPCFuncs(mux, rpccore.Routes, coreCodec, rpcLogger)
listener, err := rpcserver.StartHTTPServer(
listenAddr,
mux,
rpcLogger,
rpcserver.Config{MaxOpenConnections: n.config.RPC.MaxOpenConnections},
)
if err != nil {
return nil, err
}
listeners[i] = listener
}
// we expose a simplified api over grpc for convenience to app devs
grpcListenAddr := n.config.RPC.GRPCListenAddress
if grpcListenAddr != "" {
listener, err := grpccore.StartGRPCServer(
grpcListenAddr,
grpccore.Config{
MaxOpenConnections: n.config.RPC.GRPCMaxOpenConnections,
},
)
if err != nil {
return nil, err
}
listeners = append(listeners, listener)
}
return listeners, nil
}
// startPrometheusServer starts a Prometheus HTTP server, listening for metrics
// collectors on addr.
func (n *Node) startPrometheusServer(addr string) *http.Server {
srv := &http.Server{
Addr: addr,
Handler: promhttp.Handler(),
}
go func() {
if err := srv.ListenAndServe(); err != http.ErrServerClosed {
// Error starting or closing listener:
n.Logger.Error("Prometheus HTTP server ListenAndServe", "err", err)
}
}()
return srv
}
// Switch returns the Node's Switch.
func (n *Node) Switch() *p2p.Switch {
return n.sw
}
// BlockStore returns the Node's BlockStore.
func (n *Node) BlockStore() *bc.BlockStore {
return n.blockStore
}
// ConsensusState returns the Node's ConsensusState.
func (n *Node) ConsensusState() *cs.ConsensusState {
return n.consensusState
}
// ConsensusReactor returns the Node's ConsensusReactor.
func (n *Node) ConsensusReactor() *cs.ConsensusReactor {
return n.consensusReactor
}
// MempoolReactor returns the Node's MempoolReactor.
func (n *Node) MempoolReactor() *mempl.MempoolReactor {
return n.mempoolReactor
}
// EvidencePool returns the Node's EvidencePool.
func (n *Node) EvidencePool() *evidence.EvidencePool {
return n.evidencePool
}
// EventBus returns the Node's EventBus.
func (n *Node) EventBus() *types.EventBus {
return n.eventBus
}
// PrivValidator returns the Node's PrivValidator.
// XXX: for convenience only!
func (n *Node) PrivValidator() types.PrivValidator {
return n.privValidator
}
// GenesisDoc returns the Node's GenesisDoc.
func (n *Node) GenesisDoc() *types.GenesisDoc {
return n.genesisDoc
}
// ProxyApp returns the Node's AppConns, representing its connections to the ABCI application.
func (n *Node) ProxyApp() proxy.AppConns {
return n.proxyApp
}
func (n *Node) makeNodeInfo(nodeID p2p.ID) p2p.NodeInfo {
txIndexerStatus := "on"
if _, ok := n.txIndexer.(*null.TxIndex); ok {
txIndexerStatus = "off"
}
nodeInfo := p2p.NodeInfo{
ID: nodeID,
Network: n.genesisDoc.ChainID,
Version: version.Version,
Channels: []byte{
bc.BlockchainChannel,
cs.StateChannel, cs.DataChannel, cs.VoteChannel, cs.VoteSetBitsChannel,
mempl.MempoolChannel,
evidence.EvidenceChannel,
},
Moniker: n.config.Moniker,
Other: []string{
cmn.Fmt("amino_version=%v", amino.Version),
cmn.Fmt("p2p_version=%v", p2p.Version),
cmn.Fmt("consensus_version=%v", cs.Version),
cmn.Fmt("rpc_version=%v/%v", rpc.Version, rpccore.Version),
cmn.Fmt("tx_index=%v", txIndexerStatus),
},
}
if n.config.P2P.PexReactor {
nodeInfo.Channels = append(nodeInfo.Channels, pex.PexChannel)
}
rpcListenAddr := n.config.RPC.ListenAddress
nodeInfo.Other = append(nodeInfo.Other, cmn.Fmt("rpc_addr=%v", rpcListenAddr))
if !n.sw.IsListening() {
return nodeInfo
}
p2pListener := n.sw.Listeners()[0]
p2pHost := p2pListener.ExternalAddress().IP.String()
p2pPort := p2pListener.ExternalAddress().Port
nodeInfo.ListenAddr = cmn.Fmt("%v:%v", p2pHost, p2pPort)
return nodeInfo
}
//------------------------------------------------------------------------------
// NodeInfo returns the Node's Info from the Switch.
func (n *Node) NodeInfo() p2p.NodeInfo {
return n.sw.NodeInfo()
}
//------------------------------------------------------------------------------
var (
genesisDocKey = []byte("genesisDoc")
)
// panics if failed to unmarshal bytes
func loadGenesisDoc(db dbm.DB) (*types.GenesisDoc, error) {
bytes := db.Get(genesisDocKey)
if len(bytes) == 0 {
return nil, errors.New("Genesis doc not found")
}
var genDoc *types.GenesisDoc
err := cdc.UnmarshalJSON(bytes, &genDoc)
if err != nil {
cmn.PanicCrisis(fmt.Sprintf("Failed to load genesis doc due to unmarshaling error: %v (bytes: %X)", err, bytes))
}
return genDoc, nil
}
// panics if failed to marshal the given genesis document
func saveGenesisDoc(db dbm.DB, genDoc *types.GenesisDoc) {
bytes, err := cdc.MarshalJSON(genDoc)
if err != nil {
cmn.PanicCrisis(fmt.Sprintf("Failed to save genesis doc due to marshaling error: %v", err))
}
db.SetSync(genesisDocKey, bytes)
}