core: cache standby validators in the Blockchain

They never change, so it makes no sense parsing the keys over and over
again. It also simplifies the interface a little.

pkg/core/blockchain.go

@@ -117,6 +117,8 @@ type Blockchain struct {
 	// cache for block verification keys.
 	keyCache map[util.Uint160]map[string]*keys.PublicKey
 
+	sbValidators keys.PublicKeys
+
 	log *zap.Logger
 
 	lastBatch *storage.MemBatch
@@ -152,6 +154,10 @@ func NewBlockchain(s storage.Store, cfg config.ProtocolConfiguration, log *zap.L
 		cfg.MemPoolSize = defaultMemPoolSize
 		log.Info("mempool size is not set or wrong, setting default value", zap.Int("MemPoolSize", cfg.MemPoolSize))
 	}
+	validators, err := validatorsFromConfig(cfg)
+	if err != nil {
+		return nil, err
+	}
 	bc := &Blockchain{
 		config:        cfg,
 		dao:           dao.NewSimple(s, cfg.Magic),
@@ -161,6 +167,7 @@ func NewBlockchain(s storage.Store, cfg config.ProtocolConfiguration, log *zap.L
 		runToExitCh:   make(chan struct{}),
 		memPool:       mempool.NewMemPool(cfg.MemPoolSize),
 		keyCache:      make(map[util.Uint160]map[string]*keys.PublicKey),
+		sbValidators:  validators,
 		log:           log,
 		events:        make(chan bcEvent),
 		subCh:         make(chan interface{}),
@@ -1235,8 +1242,10 @@ func (bc *Blockchain) PoolTx(t *transaction.Transaction) error {
 }
 
 //GetStandByValidators returns validators from the configuration.
-func (bc *Blockchain) GetStandByValidators() (keys.PublicKeys, error) {
+func (bc *Blockchain) GetStandByValidators() keys.PublicKeys {
-	return getValidators(bc.config)
+	res := make(keys.PublicKeys, len(bc.sbValidators))
+	copy(res, bc.sbValidators)
+	return res
 }
 
 // GetValidators returns next block validators.

pkg/core/blockchainer/blockchainer.go

@@ -37,7 +37,7 @@ type Blockchainer interface {
 	GetNEP5TransferLog(util.Uint160) *state.NEP5TransferLog
 	GetNEP5Balances(util.Uint160) *state.NEP5Balances
 	GetValidators() ([]*keys.PublicKey, error)
-	GetStandByValidators() (keys.PublicKeys, error)
+	GetStandByValidators() keys.PublicKeys
 	GetScriptHashesForVerifying(*transaction.Transaction) ([]util.Uint160, error)
 	GetStorageItem(id int32, key []byte) *state.StorageItem
 	GetStorageItems(id int32) (map[string]*state.StorageItem, error)

pkg/core/helper_test.go

@@ -48,7 +48,7 @@ func (bc *Blockchain) newBlock(txs ...*transaction.Transaction) *block.Block {
 }
 
 func newBlock(cfg config.ProtocolConfiguration, index uint32, prev util.Uint256, txs ...*transaction.Transaction) *block.Block {
-	validators, _ := getValidators(cfg)
+	validators, _ := validatorsFromConfig(cfg)
 	vlen := len(validators)
 	valScript, _ := smartcontract.CreateMultiSigRedeemScript(
 		vlen-(vlen-1)/3,
@@ -399,10 +399,7 @@ func addCosigners(txs ...*transaction.Transaction) {
 }
 
 func signTx(bc *Blockchain, txs ...*transaction.Transaction) error {
-	validators, err := getValidators(bc.config)
+	validators := bc.GetStandByValidators()
-	if err != nil {
-		return errors.Wrap(err, "fail to sign tx")
-	}
 	rawScript, err := smartcontract.CreateMultiSigRedeemScript(len(bc.config.StandbyValidators)/2+1, validators)
 	if err != nil {
 		return errors.Wrap(err, "fail to sign tx")

pkg/core/native/native_gas.go

@@ -101,10 +101,7 @@ func (g *GAS) OnPersist(ic *interop.Context) error {
 }
 
 func getStandbyValidatorsHash(ic *interop.Context) (util.Uint160, []*keys.PublicKey, error) {
-	vs, err := ic.Chain.GetStandByValidators()
+	vs := ic.Chain.GetStandByValidators()
-	if err != nil {
-		return util.Uint160{}, nil, err
-	}
 	s, err := smartcontract.CreateMultiSigRedeemScript(len(vs)/2+1, vs)
 	if err != nil {
 		return util.Uint160{}, nil, err

pkg/core/native/native_neo.go

@@ -384,10 +384,7 @@ func (n *NEO) getRegisteredValidatorsCall(ic *interop.Context, _ []stackitem.Ite
 
 // GetValidatorsInternal returns a list of current validators.
 func (n *NEO) GetValidatorsInternal(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, error) {
-	standByValidators, err := bc.GetStandByValidators()
+	standByValidators := bc.GetStandByValidators()
-	if err != nil {
-		return nil, err
-	}
 	si := d.GetStorageItem(n.ContractID, validatorsCountKey)
 	if si == nil {
 		return standByValidators, nil

pkg/core/util.go

@@ -34,7 +34,7 @@ var (
 
 // createGenesisBlock creates a genesis block based on the given configuration.
 func createGenesisBlock(cfg config.ProtocolConfiguration) (*block.Block, error) {
-	validators, err := getValidators(cfg)
+	validators, err := validatorsFromConfig(cfg)
 	if err != nil {
 		return nil, err
 	}
@@ -91,7 +91,7 @@ func deployNativeContracts(magic netmode.Magic) *transaction.Transaction {
 	return tx
 }
 
-func getValidators(cfg config.ProtocolConfiguration) ([]*keys.PublicKey, error) {
+func validatorsFromConfig(cfg config.ProtocolConfiguration) ([]*keys.PublicKey, error) {
 	validators := make([]*keys.PublicKey, len(cfg.StandbyValidators))
 	for i, pubKeyStr := range cfg.StandbyValidators {
 		pubKey, err := keys.NewPublicKeyFromString(pubKeyStr)

pkg/core/util_test.go

@@ -34,7 +34,7 @@ func TestGetConsensusAddressMainNet(t *testing.T) {
 	cfg, err := config.Load("../../config", netmode.MainNet)
 	require.NoError(t, err)
 
-	validators, err := getValidators(cfg.ProtocolConfiguration)
+	validators, err := validatorsFromConfig(cfg.ProtocolConfiguration)
 	require.NoError(t, err)
 
 	script, err := getNextConsensusAddress(validators)

pkg/network/helper_test.go

@@ -85,7 +85,7 @@ func (chain testChain) GetNEP5Balances(util.Uint160) *state.NEP5Balances {
 func (chain testChain) GetValidators() ([]*keys.PublicKey, error) {
 	panic("TODO")
 }
-func (chain testChain) GetStandByValidators() (keys.PublicKeys, error) {
+func (chain testChain) GetStandByValidators() keys.PublicKeys {
 	panic("TODO")
 }
 func (chain testChain) GetEnrollments() ([]state.Validator, error) {

pkg/rpc/server/server_test.go

@@ -577,8 +577,7 @@ var rpcTestCases = map[string][]rpcTestCase{
 			},
 			check: func(t *testing.T, e *executor, validators interface{}) {
 				var expected []result.Validator
-				sBValidators, err := e.chain.GetStandByValidators()
+				sBValidators := e.chain.GetStandByValidators()
-				require.NoError(t, err)
 				for _, sbValidator := range sBValidators {
 					expected = append(expected, result.Validator{
 						PublicKey: *sbValidator,