Merge pull request #2323 from nspcc-dev/drop-blockchainer

Reduce blockchainer.Blockchainer use

cli/executor_test.go

@@ -12,6 +12,7 @@ import (
 
 	"github.com/nspcc-dev/neo-go/cli/input"
 	"github.com/nspcc-dev/neo-go/pkg/config"
+	"github.com/nspcc-dev/neo-go/pkg/consensus"
 	"github.com/nspcc-dev/neo-go/pkg/core"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
@@ -82,8 +83,19 @@ func newTestChain(t *testing.T, f func(*config.Config), run bool) (*core.Blockch
 	}
 
 	serverConfig := network.NewServerConfig(cfg)
-	netSrv, err := network.NewServer(serverConfig, chain, zap.NewNop())
+	netSrv, err := network.NewServer(serverConfig, chain, chain.GetStateSyncModule(), zap.NewNop())
 	require.NoError(t, err)
+	cons, err := consensus.NewService(consensus.Config{
+		Logger:                zap.NewNop(),
+		Broadcast:             netSrv.BroadcastExtensible,
+		Chain:                 chain,
+		ProtocolConfiguration: chain.GetConfig(),
+		RequestTx:             netSrv.RequestTx,
+		Wallet:                serverConfig.Wallet,
+		TimePerBlock:          serverConfig.TimePerBlock,
+	})
+	require.NoError(t, err)
+	netSrv.AddExtensibleHPService(cons, consensus.Category, cons.OnPayload, cons.OnTransaction)
 	go netSrv.Start(make(chan error, 1))
 	rpcServer := server.New(chain, cfg.ApplicationConfiguration.RPC, netSrv, nil, logger)
 	errCh := make(chan error, 2)

cli/server/server.go

@@ -2,6 +2,7 @@ package server
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"os/signal"
@@ -9,14 +10,20 @@ import (
 
 	"github.com/nspcc-dev/neo-go/cli/options"
 	"github.com/nspcc-dev/neo-go/pkg/config"
+	"github.com/nspcc-dev/neo-go/pkg/consensus"
 	"github.com/nspcc-dev/neo-go/pkg/core"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
 	"github.com/nspcc-dev/neo-go/pkg/core/chaindump"
+	corestate "github.com/nspcc-dev/neo-go/pkg/core/stateroot"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
+	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/network"
 	"github.com/nspcc-dev/neo-go/pkg/network/metrics"
 	"github.com/nspcc-dev/neo-go/pkg/rpc/server"
+	"github.com/nspcc-dev/neo-go/pkg/services/notary"
+	"github.com/nspcc-dev/neo-go/pkg/services/oracle"
+	"github.com/nspcc-dev/neo-go/pkg/services/stateroot"
 	"github.com/urfave/cli"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
@@ -316,6 +323,73 @@ func restoreDB(ctx *cli.Context) error {
 	return nil
 }
 
+func mkOracle(config network.ServerConfig, chain *core.Blockchain, serv *network.Server, log *zap.Logger) (*oracle.Oracle, error) {
+	if !config.OracleCfg.Enabled {
+		return nil, nil
+	}
+	orcCfg := oracle.Config{
+		Log:           log,
+		Network:       config.Net,
+		MainCfg:       config.OracleCfg,
+		Chain:         chain,
+		OnTransaction: serv.RelayTxn,
+	}
+	orc, err := oracle.NewOracle(orcCfg)
+	if err != nil {
+		return nil, fmt.Errorf("can't initialize Oracle module: %w", err)
+	}
+	chain.SetOracle(orc)
+	serv.AddService(orc)
+	return orc, nil
+}
+
+func mkConsensus(config network.ServerConfig, chain *core.Blockchain, serv *network.Server, log *zap.Logger) (consensus.Service, error) {
+	if config.Wallet == nil {
+		return nil, nil
+	}
+	srv, err := consensus.NewService(consensus.Config{
+		Logger:                log,
+		Broadcast:             serv.BroadcastExtensible,
+		Chain:                 chain,
+		ProtocolConfiguration: chain.GetConfig(),
+		RequestTx:             serv.RequestTx,
+		Wallet:                config.Wallet,
+		TimePerBlock:          config.TimePerBlock,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("can't initialize Consensus module: %w", err)
+	}
+
+	serv.AddExtensibleHPService(srv, consensus.Category, srv.OnPayload, srv.OnTransaction)
+	return srv, nil
+}
+
+func mkP2PNotary(config network.ServerConfig, chain *core.Blockchain, serv *network.Server, log *zap.Logger) (*notary.Notary, error) {
+	if !config.P2PNotaryCfg.Enabled {
+		return nil, nil
+	}
+	if !chain.P2PSigExtensionsEnabled() {
+		return nil, errors.New("P2PSigExtensions are disabled, but Notary service is enabled")
+	}
+	cfg := notary.Config{
+		MainCfg: config.P2PNotaryCfg,
+		Chain:   chain,
+		Log:     log,
+	}
+	n, err := notary.NewNotary(cfg, serv.Net, serv.GetNotaryPool(), func(tx *transaction.Transaction) error {
+		if err := serv.RelayTxn(tx); err != nil {
+			return fmt.Errorf("can't relay completed notary transaction: hash %s, error: %w", tx.Hash().StringLE(), err)
+		}
+		return nil
+	})
+	if err != nil {
+		return nil, fmt.Errorf("failed to create Notary module: %w", err)
+	}
+	serv.AddService(n)
+	chain.SetNotary(n)
+	return n, nil
+}
+
 func startServer(ctx *cli.Context) error {
 	cfg, err := getConfigFromContext(ctx)
 	if err != nil {
@@ -336,11 +410,30 @@ func startServer(ctx *cli.Context) error {
 		return err
 	}
 
-	serv, err := network.NewServer(serverConfig, chain, log)
+	serv, err := network.NewServer(serverConfig, chain, chain.GetStateSyncModule(), log)
 	if err != nil {
 		return cli.NewExitError(fmt.Errorf("failed to create network server: %w", err), 1)
 	}
-	rpcServer := server.New(chain, cfg.ApplicationConfiguration.RPC, serv, serv.GetOracle(), log)
+	srMod := chain.GetStateModule().(*corestate.Module) // Take full responsibility here.
+	sr, err := stateroot.New(serverConfig.StateRootCfg, srMod, log, chain, serv.BroadcastExtensible)
+	if err != nil {
+		return cli.NewExitError(fmt.Errorf("can't initialize StateRoot service: %w", err), 1)
+	}
+	serv.AddExtensibleService(sr, stateroot.Category, sr.OnPayload)
+
+	oracleSrv, err := mkOracle(serverConfig, chain, serv, log)
+	if err != nil {
+		return err
+	}
+	_, err = mkConsensus(serverConfig, chain, serv, log)
+	if err != nil {
+		return err
+	}
+	_, err = mkP2PNotary(serverConfig, chain, serv, log)
+	if err != nil {
+		return err
+	}
+	rpcServer := server.New(chain, cfg.ApplicationConfiguration.RPC, serv, oracleSrv, log)
 	errChan := make(chan error)
 
 	go serv.Start(errChan)
@@ -369,7 +462,7 @@ Main:
 					errChan <- fmt.Errorf("error while restarting rpc-server: %w", serverErr)
 					break
 				}
-				rpcServer = server.New(chain, cfg.ApplicationConfiguration.RPC, serv, serv.GetOracle(), log)
+				rpcServer = server.New(chain, cfg.ApplicationConfiguration.RPC, serv, oracleSrv, log)
 				rpcServer.Start(errChan)
 			}
 		case <-grace.Done():

internal/fakechain/fakechain.go

@@ -22,7 +22,6 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/rpc/response/result/subscriptions"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/trigger"
 	"github.com/nspcc-dev/neo-go/pkg/util"
-	"github.com/nspcc-dev/neo-go/pkg/vm"
 	uatomic "go.uber.org/atomic"
 )
 
@@ -41,7 +40,7 @@ type FakeChain struct {
 	MaxVerificationGAS       int64
 	NotaryContractScriptHash util.Uint160
 	NotaryDepositExpiration  uint32
-	PostBlock                []func(blockchainer.Blockchainer, *mempool.Pool, *block.Block)
+	PostBlock                []func(func(*transaction.Transaction, *mempool.Pool, bool) bool, *mempool.Pool, *block.Block)
 	UtilityTokenBalance      *big.Int
 }
 
@@ -104,8 +103,8 @@ func (chain *FakeChain) IsTxStillRelevant(t *transaction.Transaction, txpool *me
 	panic("TODO")
 }
 
-// InitVerificationVM initializes VM for witness check.
-func (chain *FakeChain) InitVerificationVM(v *vm.VM, getContract func(util.Uint160) (*state.Contract, error), hash util.Uint160, witness *transaction.Witness) error {
+// InitVerificationContext initializes context for witness check.
+func (chain *FakeChain) InitVerificationContext(ic *interop.Context, hash util.Uint160, witness *transaction.Witness) error {
 	panic("TODO")
 }
 
@@ -140,11 +139,6 @@ func (chain *FakeChain) GetNotaryBalance(acc util.Uint160) *big.Int {
 	panic("TODO")
 }
 
-// GetPolicer implements Blockchainer interface.
-func (chain *FakeChain) GetPolicer() blockchainer.Policer {
-	return chain
-}
-
 // GetBaseExecFee implements Policer interface.
 func (chain *FakeChain) GetBaseExecFee() int64 {
 	return interop.DefaultBaseExecFee
@@ -164,12 +158,12 @@ func (chain *FakeChain) GetMaxVerificationGAS() int64 {
 }
 
 // PoolTxWithData implements Blockchainer interface.
-func (chain *FakeChain) PoolTxWithData(t *transaction.Transaction, data interface{}, mp *mempool.Pool, feer mempool.Feer, verificationFunction func(bc blockchainer.Blockchainer, t *transaction.Transaction, data interface{}) error) error {
+func (chain *FakeChain) PoolTxWithData(t *transaction.Transaction, data interface{}, mp *mempool.Pool, feer mempool.Feer, verificationFunction func(t *transaction.Transaction, data interface{}) error) error {
 	return chain.poolTxWithData(t, data, mp)
 }
 
 // RegisterPostBlock implements Blockchainer interface.
-func (chain *FakeChain) RegisterPostBlock(f func(blockchainer.Blockchainer, *mempool.Pool, *block.Block)) {
+func (chain *FakeChain) RegisterPostBlock(f func(func(*transaction.Transaction, *mempool.Pool, bool) bool, *mempool.Pool, *block.Block)) {
 	chain.PostBlock = append(chain.PostBlock, f)
 }
 
@@ -326,18 +320,13 @@ func (chain *FakeChain) GetStateModule() blockchainer.StateRoot {
 	return nil
 }
 
-// GetStateSyncModule implements Blockchainer interface.
-func (chain *FakeChain) GetStateSyncModule() blockchainer.StateSync {
-	return &FakeStateSync{}
-}
-
 // GetStorageItem implements Blockchainer interface.
 func (chain *FakeChain) GetStorageItem(id int32, key []byte) state.StorageItem {
 	panic("TODO")
 }
 
 // GetTestVM implements Blockchainer interface.
-func (chain *FakeChain) GetTestVM(t trigger.Type, tx *transaction.Transaction, b *block.Block) (*vm.VM, func()) {
+func (chain *FakeChain) GetTestVM(t trigger.Type, tx *transaction.Transaction, b *block.Block) *interop.Context {
 	panic("TODO")
 }
 

internal/testchain/transaction.go

@@ -120,7 +120,7 @@ func SignTxCommittee(bc blockchainer.Blockchainer, txs ...*transaction.Transacti
 func signTxGeneric(bc blockchainer.Blockchainer, sign func(hash.Hashable) []byte, verif []byte, txs ...*transaction.Transaction) {
 	for _, tx := range txs {
 		size := io.GetVarSize(tx)
-		netFee, sizeDelta := fee.Calculate(bc.GetPolicer().GetBaseExecFee(), verif)
+		netFee, sizeDelta := fee.Calculate(bc.GetBaseExecFee(), verif)
 		tx.NetworkFee += netFee
 		size += sizeDelta
 		tx.NetworkFee += int64(size) * bc.FeePerByte()

pkg/consensus/consensus.go

@@ -14,6 +14,7 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
 	coreb "github.com/nspcc-dev/neo-go/pkg/core/block"
 	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
+	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	"github.com/nspcc-dev/neo-go/pkg/core/mempool"
 	"github.com/nspcc-dev/neo-go/pkg/core/native"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
@@ -43,6 +44,22 @@ const nsInMs = 1000000
 // Category is message category for extensible payloads.
 const Category = "dBFT"
 
+// Ledger is the interface to Blockchain sufficient for Service.
+type Ledger interface {
+	AddBlock(block *coreb.Block) error
+	ApplyPolicyToTxSet([]*transaction.Transaction) []*transaction.Transaction
+	GetMemPool() *mempool.Pool
+	GetNextBlockValidators() ([]*keys.PublicKey, error)
+	GetStateModule() blockchainer.StateRoot
+	GetTransaction(util.Uint256) (*transaction.Transaction, uint32, error)
+	GetValidators() ([]*keys.PublicKey, error)
+	PoolTx(t *transaction.Transaction, pools ...*mempool.Pool) error
+	SubscribeForBlocks(ch chan<- *coreb.Block)
+	UnsubscribeFromBlocks(ch chan<- *coreb.Block)
+	interop.Ledger
+	mempool.Feer
+}
+
 // Service represents consensus instance.
 type Service interface {
 	// Start initializes dBFT and starts event loop for consensus service.
@@ -52,7 +69,7 @@ type Service interface {
 	Shutdown()
 
 	// OnPayload is a callback to notify Service about new received payload.
-	OnPayload(p *npayload.Extensible)
+	OnPayload(p *npayload.Extensible) error
 	// OnTransaction is a callback to notify Service about new received transaction.
 	OnTransaction(tx *transaction.Transaction)
 }
@@ -92,8 +109,8 @@ type Config struct {
 	// Broadcast is a callback which is called to notify server
 	// about new consensus payload to sent.
 	Broadcast func(p *npayload.Extensible)
-	// Chain is a core.Blockchainer instance.
-	Chain blockchainer.Blockchainer
+	// Chain is a Ledger instance.
+	Chain Ledger
 	// ProtocolConfiguration contains protocol settings.
 	ProtocolConfiguration config.ProtocolConfiguration
 	// RequestTx is a callback to which will be called
@@ -129,10 +146,6 @@ func NewService(cfg Config) (Service, error) {
 		finished:     make(chan struct{}),
 	}
 
-	if cfg.Wallet == nil {
-		return srv, nil
-	}
-
 	var err error
 
 	if srv.wallet, err = wallet.NewWalletFromFile(cfg.Wallet.Path); err != nil {
@@ -369,26 +382,27 @@ func (s *service) payloadFromExtensible(ep *npayload.Extensible) *Payload {
 }
 
 // OnPayload handles Payload receive.
-func (s *service) OnPayload(cp *npayload.Extensible) {
+func (s *service) OnPayload(cp *npayload.Extensible) error {
 	log := s.log.With(zap.Stringer("hash", cp.Hash()))
 	p := s.payloadFromExtensible(cp)
 	// decode payload data into message
 	if err := p.decodeData(); err != nil {
 		log.Info("can't decode payload data", zap.Error(err))
-		return
+		return nil
 	}
 
 	if !s.validatePayload(p) {
 		log.Info("can't validate payload")
-		return
+		return nil
 	}
 
 	if s.dbft == nil || !s.started.Load() {
 		log.Debug("dbft is inactive or not started yet")
-		return
+		return nil
 	}
 
 	s.messages <- *p
+	return nil
 }
 
 func (s *service) OnTransaction(tx *transaction.Transaction) {

pkg/consensus/consensus_test.go

@@ -13,7 +13,6 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
 	"github.com/nspcc-dev/neo-go/pkg/core"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/fee"
 	"github.com/nspcc-dev/neo-go/pkg/core/native"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
@@ -351,7 +350,7 @@ func TestService_OnPayload(t *testing.T) {
 	p.encodeData()
 
 	// sender is invalid
-	srv.OnPayload(&p.Extensible)
+	require.NoError(t, srv.OnPayload(&p.Extensible))
 	shouldNotReceive(t, srv.messages)
 
 	p = new(Payload)
@@ -359,16 +358,17 @@ func TestService_OnPayload(t *testing.T) {
 	p.Sender = priv.GetScriptHash()
 	p.SetPayload(&prepareRequest{})
 	require.NoError(t, p.Sign(priv))
-	srv.OnPayload(&p.Extensible)
+	require.NoError(t, srv.OnPayload(&p.Extensible))
 	shouldReceive(t, srv.messages)
 }
 
 func TestVerifyBlock(t *testing.T) {
 	srv := newTestService(t)
 
+	bc := srv.Chain.(*core.Blockchain)
 	srv.lastTimestamp = 1
 	t.Run("good empty", func(t *testing.T) {
-		b := testchain.NewBlock(t, srv.Chain, 1, 0)
+		b := testchain.NewBlock(t, bc, 1, 0)
 		require.True(t, srv.verifyBlock(&neoBlock{Block: *b}))
 	})
 	t.Run("good pooled tx", func(t *testing.T) {
@@ -377,7 +377,7 @@ func TestVerifyBlock(t *testing.T) {
 		addSender(t, tx)
 		signTx(t, srv.Chain, tx)
 		require.NoError(t, srv.Chain.PoolTx(tx))
-		b := testchain.NewBlock(t, srv.Chain, 1, 0, tx)
+		b := testchain.NewBlock(t, bc, 1, 0, tx)
 		require.True(t, srv.verifyBlock(&neoBlock{Block: *b}))
 	})
 	t.Run("good non-pooled tx", func(t *testing.T) {
@@ -385,7 +385,7 @@ func TestVerifyBlock(t *testing.T) {
 		tx.ValidUntilBlock = 1
 		addSender(t, tx)
 		signTx(t, srv.Chain, tx)
-		b := testchain.NewBlock(t, srv.Chain, 1, 0, tx)
+		b := testchain.NewBlock(t, bc, 1, 0, tx)
 		require.True(t, srv.verifyBlock(&neoBlock{Block: *b}))
 	})
 	t.Run("good conflicting tx", func(t *testing.T) {
@@ -402,11 +402,11 @@ func TestVerifyBlock(t *testing.T) {
 		signTx(t, srv.Chain, tx2)
 		require.NoError(t, srv.Chain.PoolTx(tx1))
 		require.Error(t, srv.Chain.PoolTx(tx2))
-		b := testchain.NewBlock(t, srv.Chain, 1, 0, tx2)
+		b := testchain.NewBlock(t, bc, 1, 0, tx2)
 		require.True(t, srv.verifyBlock(&neoBlock{Block: *b}))
 	})
 	t.Run("bad old", func(t *testing.T) {
-		b := testchain.NewBlock(t, srv.Chain, 1, 0)
+		b := testchain.NewBlock(t, bc, 1, 0)
 		b.Index = srv.Chain.BlockHeight()
 		require.False(t, srv.verifyBlock(&neoBlock{Block: *b}))
 	})
@@ -417,11 +417,11 @@ func TestVerifyBlock(t *testing.T) {
 		tx.ValidUntilBlock = 1
 		addSender(t, tx)
 		signTx(t, srv.Chain, tx)
-		b := testchain.NewBlock(t, srv.Chain, 1, 0, tx)
+		b := testchain.NewBlock(t, bc, 1, 0, tx)
 		require.False(t, srv.verifyBlock(&neoBlock{Block: *b}))
 	})
 	t.Run("bad timestamp", func(t *testing.T) {
-		b := testchain.NewBlock(t, srv.Chain, 1, 0)
+		b := testchain.NewBlock(t, bc, 1, 0)
 		b.Timestamp = srv.lastTimestamp - 1
 		require.False(t, srv.verifyBlock(&neoBlock{Block: *b}))
 	})
@@ -431,7 +431,7 @@ func TestVerifyBlock(t *testing.T) {
 		addSender(t, tx)
 		signTx(t, srv.Chain, tx)
 		tx.Scripts[0].InvocationScript[16] = ^tx.Scripts[0].InvocationScript[16]
-		b := testchain.NewBlock(t, srv.Chain, 1, 0, tx)
+		b := testchain.NewBlock(t, bc, 1, 0, tx)
 		require.False(t, srv.verifyBlock(&neoBlock{Block: *b}))
 	})
 	t.Run("bad big sys fee", func(t *testing.T) {
@@ -442,7 +442,7 @@ func TestVerifyBlock(t *testing.T) {
 			addSender(t, txes[i])
 			signTx(t, srv.Chain, txes[i])
 		}
-		b := testchain.NewBlock(t, srv.Chain, 1, 0, txes...)
+		b := testchain.NewBlock(t, bc, 1, 0, txes...)
 		require.False(t, srv.verifyBlock(&neoBlock{Block: *b}))
 	})
 }
@@ -532,7 +532,7 @@ func addSender(t *testing.T, txs ...*transaction.Transaction) {
 	}
 }
 
-func signTx(t *testing.T, bc blockchainer.Blockchainer, txs ...*transaction.Transaction) {
+func signTx(t *testing.T, bc Ledger, txs ...*transaction.Transaction) {
 	validators := make([]*keys.PublicKey, 4)
 	privNetKeys := make([]*keys.PrivateKey, 4)
 	for i := 0; i < 4; i++ {
@@ -544,7 +544,7 @@ func signTx(t *testing.T, bc blockchainer.Blockchainer, txs ...*transaction.Tran
 	require.NoError(t, err)
 	for _, tx := range txs {
 		size := io.GetVarSize(tx)
-		netFee, sizeDelta := fee.Calculate(bc.GetPolicer().GetBaseExecFee(), rawScript)
+		netFee, sizeDelta := fee.Calculate(bc.GetBaseExecFee(), rawScript)
 		tx.NetworkFee += +netFee
 		size += sizeDelta
 		tx.NetworkFee += int64(size) * bc.FeePerByte()

pkg/core/blockchain.go

@@ -150,7 +150,7 @@ type Blockchain struct {
 
 	// postBlock is a set of callback methods which should be run under the Blockchain lock after new block is persisted.
 	// Block's transactions are passed via mempool.
-	postBlock []func(blockchainer.Blockchainer, *mempool.Pool, *block.Block)
+	postBlock []func(func(*transaction.Transaction, *mempool.Pool, bool) bool, *mempool.Pool, *block.Block)
 
 	sbCommittee keys.PublicKeys
 
@@ -267,7 +267,7 @@ func NewBlockchain(s storage.Store, cfg config.ProtocolConfiguration, log *zap.L
 		contracts:   *native.NewContracts(cfg),
 	}
 
-	bc.stateRoot = stateroot.NewModule(bc, bc.log, bc.dao.Store)
+	bc.stateRoot = stateroot.NewModule(bc.GetConfig(), bc.VerifyWitness, bc.log, bc.dao.Store)
 	bc.contracts.Designate.StateRootService = bc.stateRoot
 
 	if err := bc.init(); err != nil {
@@ -929,8 +929,8 @@ func (bc *Blockchain) GetStateModule() blockchainer.StateRoot {
 }
 
 // GetStateSyncModule returns new state sync service instance.
-func (bc *Blockchain) GetStateSyncModule() blockchainer.StateSync {
-	return statesync.NewModule(bc, bc.log, bc.dao, bc.jumpToState)
+func (bc *Blockchain) GetStateSyncModule() *statesync.Module {
+	return statesync.NewModule(bc, bc.stateRoot, bc.log, bc.dao, bc.jumpToState)
 }
 
 // storeBlock performs chain update using the block given, it executes all
@@ -1157,7 +1157,7 @@ func (bc *Blockchain) storeBlock(block *block.Block, txpool *mempool.Pool) error
 	atomic.StoreUint32(&bc.blockHeight, block.Index)
 	bc.memPool.RemoveStale(func(tx *transaction.Transaction) bool { return bc.IsTxStillRelevant(tx, txpool, false) }, bc)
 	for _, f := range bc.postBlock {
-		f(bc, txpool, block)
+		f(bc.IsTxStillRelevant, txpool, block)
 	}
 	if err := bc.updateExtensibleWhitelist(block.Index); err != nil {
 		bc.lock.Unlock()
@@ -2095,12 +2095,12 @@ func (bc *Blockchain) PoolTx(t *transaction.Transaction, pools ...*mempool.Pool)
 }
 
 // PoolTxWithData verifies and tries to add given transaction with additional data into the mempool.
-func (bc *Blockchain) PoolTxWithData(t *transaction.Transaction, data interface{}, mp *mempool.Pool, feer mempool.Feer, verificationFunction func(bc blockchainer.Blockchainer, tx *transaction.Transaction, data interface{}) error) error {
+func (bc *Blockchain) PoolTxWithData(t *transaction.Transaction, data interface{}, mp *mempool.Pool, feer mempool.Feer, verificationFunction func(tx *transaction.Transaction, data interface{}) error) error {
 	bc.lock.RLock()
 	defer bc.lock.RUnlock()
 
 	if verificationFunction != nil {
-		err := verificationFunction(bc, t, data)
+		err := verificationFunction(t, data)
 		if err != nil {
 			return err
 		}
@@ -2140,14 +2140,14 @@ func (bc *Blockchain) GetEnrollments() ([]state.Validator, error) {
 	return bc.contracts.NEO.GetCandidates(bc.dao)
 }
 
-// GetTestVM returns a VM setup for a test run of some sort of code and finalizer function.
-func (bc *Blockchain) GetTestVM(t trigger.Type, tx *transaction.Transaction, b *block.Block) (*vm.VM, func()) {
+// GetTestVM returns an interop context with VM set up for a test run.
+func (bc *Blockchain) GetTestVM(t trigger.Type, tx *transaction.Transaction, b *block.Block) *interop.Context {
 	d := bc.dao.GetWrapped().(*dao.Simple)
 	systemInterop := bc.newInteropContext(t, d, b, tx)
 	vm := systemInterop.SpawnVM()
 	vm.SetPriceGetter(systemInterop.GetPrice)
 	vm.LoadToken = contract.LoadToken(systemInterop)
-	return vm, systemInterop.Finalize
+	return systemInterop
 }
 
 // Various witness verification errors.
@@ -2162,8 +2162,8 @@ var (
 	ErrInvalidVerificationContract = errors.New("verification contract is missing `verify` method")
 )
 
-// InitVerificationVM initializes VM for witness check.
-func (bc *Blockchain) InitVerificationVM(v *vm.VM, getContract func(util.Uint160) (*state.Contract, error), hash util.Uint160, witness *transaction.Witness) error {
+// InitVerificationContext initializes context for witness check.
+func (bc *Blockchain) InitVerificationContext(ic *interop.Context, hash util.Uint160, witness *transaction.Witness) error {
 	if len(witness.VerificationScript) != 0 {
 		if witness.ScriptHash() != hash {
 			return ErrWitnessHashMismatch
@@ -2175,9 +2175,9 @@ func (bc *Blockchain) InitVerificationVM(v *vm.VM, getContract func(util.Uint160
 		if err != nil {
 			return fmt.Errorf("%w: %v", ErrInvalidVerification, err)
 		}
-		v.LoadScriptWithHash(witness.VerificationScript, hash, callflag.ReadOnly)
+		ic.VM.LoadScriptWithHash(witness.VerificationScript, hash, callflag.ReadOnly)
 	} else {
-		cs, err := getContract(hash)
+		cs, err := ic.GetContract(hash)
 		if err != nil {
 			return ErrUnknownVerificationContract
 		}
@@ -2191,7 +2191,8 @@ func (bc *Blockchain) InitVerificationVM(v *vm.VM, getContract func(util.Uint160
 		if md != nil {
 			initOffset = md.Offset
 		}
-		v.LoadNEFMethod(&cs.NEF, util.Uint160{}, hash, callflag.ReadOnly,
+		ic.Invocations[cs.Hash]++
+		ic.VM.LoadNEFMethod(&cs.NEF, util.Uint160{}, hash, callflag.ReadOnly,
 			true, verifyOffset, initOffset)
 	}
 	if len(witness.InvocationScript) != 0 {
@@ -2199,7 +2200,7 @@ func (bc *Blockchain) InitVerificationVM(v *vm.VM, getContract func(util.Uint160
 		if err != nil {
 			return fmt.Errorf("%w: %v", ErrInvalidInvocation, err)
 		}
-		v.LoadScript(witness.InvocationScript)
+		ic.VM.LoadScript(witness.InvocationScript)
 	}
 	return nil
 }
@@ -2223,7 +2224,7 @@ func (bc *Blockchain) verifyHashAgainstScript(hash util.Uint160, witness *transa
 	vm.SetPriceGetter(interopCtx.GetPrice)
 	vm.LoadToken = contract.LoadToken(interopCtx)
 	vm.GasLimit = gas
-	if err := bc.InitVerificationVM(vm, interopCtx.GetContract, hash, witness); err != nil {
+	if err := bc.InitVerificationContext(interopCtx, hash, witness); err != nil {
 		return 0, err
 	}
 	err := interopCtx.Exec()
@@ -2331,17 +2332,10 @@ func (bc *Blockchain) P2PSigExtensionsEnabled() bool {
 
 // RegisterPostBlock appends provided function to the list of functions which should be run after new block
 // is stored.
-func (bc *Blockchain) RegisterPostBlock(f func(blockchainer.Blockchainer, *mempool.Pool, *block.Block)) {
+func (bc *Blockchain) RegisterPostBlock(f func(func(*transaction.Transaction, *mempool.Pool, bool) bool, *mempool.Pool, *block.Block)) {
 	bc.postBlock = append(bc.postBlock, f)
 }
 
-// -- start Policer.
-
-// GetPolicer provides access to policy values via Policer interface.
-func (bc *Blockchain) GetPolicer() blockchainer.Policer {
-	return bc
-}
-
 // GetBaseExecFee return execution price for `NOP`.
 func (bc *Blockchain) GetBaseExecFee() int64 {
 	return bc.contracts.Policy.GetExecFeeFactorInternal(bc.dao)
@@ -2359,5 +2353,3 @@ func (bc *Blockchain) GetStoragePrice() int64 {
 	}
 	return bc.contracts.Policy.GetStoragePriceInternal(bc.dao)
 }
-
-// -- end Policer.

pkg/core/blockchain_test.go

@@ -16,7 +16,6 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/chaindump"
 	"github.com/nspcc-dev/neo-go/pkg/core/fee"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop/interopnames"
@@ -1073,7 +1072,7 @@ func TestVerifyTx(t *testing.T) {
 		}
 
 		mp := mempool.New(10, 1, false)
-		verificationF := func(bc blockchainer.Blockchainer, tx *transaction.Transaction, data interface{}) error {
+		verificationF := func(tx *transaction.Transaction, data interface{}) error {
 			if data.(int) > 5 {
 				return errors.New("bad data")
 			}

pkg/core/blockchainer/blockchainer.go

@@ -6,6 +6,7 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
 	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer/services"
+	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	"github.com/nspcc-dev/neo-go/pkg/core/mempool"
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
@@ -14,18 +15,19 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/rpc/response/result/subscriptions"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/trigger"
 	"github.com/nspcc-dev/neo-go/pkg/util"
-	"github.com/nspcc-dev/neo-go/pkg/vm"
 )
 
 // Blockchainer is an interface that abstract the implementation
 // of the blockchain.
 type Blockchainer interface {
 	ApplyPolicyToTxSet([]*transaction.Transaction) []*transaction.Transaction
+	AddBlock(block *block.Block) error
+	AddHeaders(...*block.Header) error
+	BlockHeight() uint32
 	GetConfig() config.ProtocolConfiguration
-	Blockqueuer // Blockqueuer interface
 	CalculateClaimable(h util.Uint160, endHeight uint32) (*big.Int, error)
 	Close()
-	InitVerificationVM(v *vm.VM, getContract func(util.Uint160) (*state.Contract, error), hash util.Uint160, witness *transaction.Witness) error
+	InitVerificationContext(ic *interop.Context, hash util.Uint160, witness *transaction.Witness) error
 	IsTxStillRelevant(t *transaction.Transaction, txpool *mempool.Pool, isPartialTx bool) bool
 	HeaderHeight() uint32
 	GetBlock(hash util.Uint256) (*block.Block, error)
@@ -53,22 +55,19 @@ type Blockchainer interface {
 	GetTokenLastUpdated(acc util.Uint160) (map[int32]uint32, error)
 	GetNotaryContractScriptHash() util.Uint160
 	GetNotaryBalance(acc util.Uint160) *big.Int
-	GetPolicer() Policer
 	GetValidators() ([]*keys.PublicKey, error)
 	GetStandByCommittee() keys.PublicKeys
 	GetStandByValidators() keys.PublicKeys
 	GetStateModule() StateRoot
-	GetStateSyncModule() StateSync
 	GetStorageItem(id int32, key []byte) state.StorageItem
 	GetStorageItems(id int32) ([]state.StorageItemWithKey, error)
-	GetTestVM(t trigger.Type, tx *transaction.Transaction, b *block.Block) (*vm.VM, func())
+	GetTestVM(t trigger.Type, tx *transaction.Transaction, b *block.Block) *interop.Context
 	GetTransaction(util.Uint256) (*transaction.Transaction, uint32, error)
 	SetOracle(service services.Oracle)
 	mempool.Feer // fee interface
 	ManagementContractHash() util.Uint160
 	PoolTx(t *transaction.Transaction, pools ...*mempool.Pool) error
-	PoolTxWithData(t *transaction.Transaction, data interface{}, mp *mempool.Pool, feer mempool.Feer, verificationFunction func(bc Blockchainer, t *transaction.Transaction, data interface{}) error) error
-	RegisterPostBlock(f func(Blockchainer, *mempool.Pool, *block.Block))
+	PoolTxWithData(t *transaction.Transaction, data interface{}, mp *mempool.Pool, feer mempool.Feer, verificationFunction func(t *transaction.Transaction, data interface{}) error) error
 	SetNotary(mod services.Notary)
 	SubscribeForBlocks(ch chan<- *block.Block)
 	SubscribeForExecutions(ch chan<- *state.AppExecResult)
@@ -81,4 +80,9 @@ type Blockchainer interface {
 	UnsubscribeFromExecutions(ch chan<- *state.AppExecResult)
 	UnsubscribeFromNotifications(ch chan<- *subscriptions.NotificationEvent)
 	UnsubscribeFromTransactions(ch chan<- *transaction.Transaction)
+	// Policer.
+	GetBaseExecFee() int64
+	GetMaxVerificationGAS() int64
+	GetStoragePrice() int64
+	FeePerByte() int64
 }

pkg/core/blockchainer/blockqueuer.go

@@ -1,10 +0,0 @@
-package blockchainer
-
-import "github.com/nspcc-dev/neo-go/pkg/core/block"
-
-// Blockqueuer is an interface for blockqueue.
-type Blockqueuer interface {
-	AddBlock(block *block.Block) error
-	AddHeaders(...*block.Header) error
-	BlockHeight() uint32
-}

pkg/core/blockchainer/policer.go

@@ -1,9 +0,0 @@
-package blockchainer
-
-// Policer is an interface that abstracts the implementation of policy methods.
-type Policer interface {
-	GetBaseExecFee() int64
-	GetMaxVerificationGAS() int64
-	GetStoragePrice() int64
-	FeePerByte() int64
-}

pkg/core/blockchainer/services/oracle.go

@@ -16,8 +16,8 @@ type Oracle interface {
 	UpdateOracleNodes(keys.PublicKeys)
 	// UpdateNativeContract updates oracle contract native script and hash.
 	UpdateNativeContract([]byte, []byte, util.Uint160, int)
-	// Run runs oracle module. Must be invoked in a separate goroutine.
-	Run()
+	// Start runs oracle module.
+	Start()
 	// Shutdown shutdowns oracle module.
 	Shutdown()
 }

pkg/core/blockchainer/state_root.go

@@ -3,14 +3,11 @@ package blockchainer
 import (
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
-	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 )
 
 // StateRoot represents local state root module.
 type StateRoot interface {
-	AddStateRoot(root *state.MPTRoot) error
-	CleanStorage() error
 	CurrentLocalHeight() uint32
 	CurrentLocalStateRoot() util.Uint256
 	CurrentValidatedHeight() uint32
@@ -18,7 +15,4 @@ type StateRoot interface {
 	GetState(root util.Uint256, key []byte) ([]byte, error)
 	GetStateProof(root util.Uint256, key []byte) ([][]byte, error)
 	GetStateRoot(height uint32) (*state.MPTRoot, error)
-	GetStateValidators(height uint32) keys.PublicKeys
-	SetUpdateValidatorsCallback(func(uint32, keys.PublicKeys))
-	UpdateStateValidators(height uint32, pubs keys.PublicKeys)
 }

pkg/core/chaindump/dump.go

@@ -3,14 +3,23 @@ package chaindump
 import (
 	"fmt"
 
+	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/io"
+	"github.com/nspcc-dev/neo-go/pkg/util"
 )
 
+// DumperRestorer in the interface to get/add blocks from/to.
+type DumperRestorer interface {
+	AddBlock(block *block.Block) error
+	GetBlock(hash util.Uint256) (*block.Block, error)
+	GetConfig() config.ProtocolConfiguration
+	GetHeaderHash(int) util.Uint256
+}
+
 // Dump writes count blocks from start to the provided writer.
 // Note: header needs to be written separately by client.
-func Dump(bc blockchainer.Blockchainer, w *io.BinWriter, start, count uint32) error {
+func Dump(bc DumperRestorer, w *io.BinWriter, start, count uint32) error {
 	for i := start; i < start+count; i++ {
 		bh := bc.GetHeaderHash(int(i))
 		b, err := bc.GetBlock(bh)
@@ -31,7 +40,7 @@ func Dump(bc blockchainer.Blockchainer, w *io.BinWriter, start, count uint32) er
 
 // Restore restores blocks from provided reader.
 // f is called after addition of every block.
-func Restore(bc blockchainer.Blockchainer, r *io.BinReader, skip, count uint32, f func(b *block.Block) error) error {
+func Restore(bc DumperRestorer, r *io.BinReader, skip, count uint32, f func(b *block.Block) error) error {
 	readBlock := func(r *io.BinReader) ([]byte, error) {
 		var size = r.ReadU32LE()
 		buf := make([]byte, size)

pkg/core/helper_test.go

@@ -635,12 +635,12 @@ func setTxSystemFee(bc *Blockchain, sysFee int64, tx *transaction.Transaction) {
 	}
 
 	ttx := *tx // prevent setting 'hash' field
-	v, f := bc.GetTestVM(trigger.Application, &ttx, b)
-	defer f()
+	ic := bc.GetTestVM(trigger.Application, &ttx, b)
+	defer ic.Finalize()
 
-	v.LoadWithFlags(tx.Script, callflag.All)
-	_ = v.Run()
-	tx.SystemFee = v.GasConsumed()
+	ic.VM.LoadWithFlags(tx.Script, callflag.All)
+	_ = ic.VM.Run()
+	tx.SystemFee = ic.VM.GasConsumed()
 }
 
 func signTxWithAccounts(chain *Blockchain, sysFee int64, tx *transaction.Transaction, accs ...*wallet.Account) {

pkg/core/interop/context.go

@@ -8,13 +8,14 @@ import (
 	"sort"
 	"strings"
 
+	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/dao"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop/interopnames"
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
+	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
@@ -33,9 +34,22 @@ const (
 	DefaultBaseExecFee = 30
 )
 
+// Ledger is the interface to Blockchain required for Context functionality.
+type Ledger interface {
+	BlockHeight() uint32
+	CurrentBlockHash() util.Uint256
+	GetBaseExecFee() int64
+	GetBlock(hash util.Uint256) (*block.Block, error)
+	GetConfig() config.ProtocolConfiguration
+	GetHeaderHash(int) util.Uint256
+	GetStandByCommittee() keys.PublicKeys
+	GetStandByValidators() keys.PublicKeys
+	GetStoragePrice() int64
+}
+
 // Context represents context in which interops are executed.
 type Context struct {
-	Chain         blockchainer.Blockchainer
+	Chain         Ledger
 	Container     hash.Hashable
 	Network       uint32
 	Natives       []Contract
@@ -56,14 +70,14 @@ type Context struct {
 }
 
 // NewContext returns new interop context.
-func NewContext(trigger trigger.Type, bc blockchainer.Blockchainer, d dao.DAO,
+func NewContext(trigger trigger.Type, bc Ledger, d dao.DAO,
 	getContract func(dao.DAO, util.Uint160) (*state.Contract, error), natives []Contract,
 	block *block.Block, tx *transaction.Transaction, log *zap.Logger) *Context {
 	baseExecFee := int64(DefaultBaseExecFee)
 	dao := d.GetWrapped()
 
 	if bc != nil && (block == nil || block.Index != 0) {
-		baseExecFee = bc.GetPolicer().GetBaseExecFee()
+		baseExecFee = bc.GetBaseExecFee()
 	}
 	return &Context{
 		Chain:       bc,

pkg/core/interop_system.go

@@ -125,7 +125,7 @@ func putWithContext(ic *interop.Context, stc *StorageContext, key []byte, value
 			sizeInc = (len(si)-1)/4 + 1 + len(value) - len(si)
 		}
 	}
-	if !ic.VM.AddGas(int64(sizeInc) * ic.Chain.GetPolicer().GetStoragePrice()) {
+	if !ic.VM.AddGas(int64(sizeInc) * ic.Chain.GetStoragePrice()) {
 		return errGasLimitExceeded
 	}
 	return ic.DAO.PutStorageItem(stc.ID, key, value)

pkg/core/native/designate.go

@@ -8,7 +8,6 @@ import (
 	"sort"
 	"sync/atomic"
 
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer/services"
 	"github.com/nspcc-dev/neo-go/pkg/core/dao"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop"
@@ -16,6 +15,7 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/native/nativenames"
 	"github.com/nspcc-dev/neo-go/pkg/core/native/noderoles"
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
+	"github.com/nspcc-dev/neo-go/pkg/core/stateroot"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
@@ -43,7 +43,7 @@ type Designate struct {
 	// NotaryService represents Notary node module.
 	NotaryService atomic.Value
 	// StateRootService represents StateRoot node module.
-	StateRootService blockchainer.StateRoot
+	StateRootService *stateroot.Module
 }
 
 type roleData struct {

pkg/core/native/interop.go

@@ -41,8 +41,8 @@ func Call(ic *interop.Context) error {
 		return fmt.Errorf("missing call flags for native %d `%s` operation call: %05b vs %05b",
 			version, m.MD.Name, ic.VM.Context().GetCallFlags(), m.RequiredFlags)
 	}
-	invokeFee := m.CPUFee*ic.Chain.GetPolicer().GetBaseExecFee() +
-		m.StorageFee*ic.Chain.GetPolicer().GetStoragePrice()
+	invokeFee := m.CPUFee*ic.Chain.GetBaseExecFee() +
+		m.StorageFee*ic.Chain.GetStoragePrice()
 	if !ic.VM.AddGas(invokeFee) {
 		return errors.New("gas limit exceeded")
 	}

pkg/core/native/ledger.go

@@ -6,7 +6,6 @@ import (
 	"math/big"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/dao"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	"github.com/nspcc-dev/neo-go/pkg/core/native/nativenames"
@@ -145,17 +144,17 @@ func (l *Ledger) getTransactionFromBlock(ic *interop.Context, params []stackitem
 
 // isTraceableBlock defines whether we're able to give information about
 // the block with index specified.
-func isTraceableBlock(bc blockchainer.Blockchainer, index uint32) bool {
+func isTraceableBlock(bc interop.Ledger, index uint32) bool {
 	height := bc.BlockHeight()
 	MaxTraceableBlocks := bc.GetConfig().MaxTraceableBlocks
 	return index <= height && index+MaxTraceableBlocks > height
 }
 
 // getBlockHashFromItem converts given stackitem.Item to block hash using given
-// Blockchainer if needed. Interop functions accept both block numbers and
+// Ledger if needed. Interop functions accept both block numbers and
 // block hashes as parameters, thus this function is needed. It's supposed to
 // be called within VM context, so it panics if anything goes wrong.
-func getBlockHashFromItem(bc blockchainer.Blockchainer, item stackitem.Item) util.Uint256 {
+func getBlockHashFromItem(bc interop.Ledger, item stackitem.Item) util.Uint256 {
 	bigindex, err := item.TryInteger()
 	if err == nil && bigindex.IsUint64() {
 		index := bigindex.Uint64()

pkg/core/native/management.go

@@ -198,7 +198,7 @@ func (m *Management) getNefAndManifestFromItems(ic *interop.Context, args []stac
 		return nil, nil, fmt.Errorf("invalid manifest: %w", err)
 	}
 
-	gas := ic.Chain.GetPolicer().GetStoragePrice() * int64(len(nefBytes)+len(manifestBytes))
+	gas := ic.Chain.GetStoragePrice() * int64(len(nefBytes)+len(manifestBytes))
 	if isDeploy {
 		fee := m.GetMinimumDeploymentFee(ic.DAO)
 		if fee > gas {

pkg/core/native/native_neo.go

@@ -10,7 +10,6 @@ import (
 	"strings"
 	"sync/atomic"
 
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/dao"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop/runtime"
@@ -244,7 +243,7 @@ func (n *NEO) Initialize(ic *interop.Context) error {
 // InitializeCache initializes all NEO cache with the proper values from storage.
 // Cache initialisation should be done apart from Initialize because Initialize is
 // called only when deploying native contracts.
-func (n *NEO) InitializeCache(bc blockchainer.Blockchainer, d dao.DAO) error {
+func (n *NEO) InitializeCache(bc interop.Ledger, d dao.DAO) error {
 	var committee = keysWithVotes{}
 	si := d.GetStorageItem(n.ID, prefixCommittee)
 	if err := committee.DecodeBytes(si); err != nil {
@@ -264,7 +263,7 @@ func (n *NEO) InitializeCache(bc blockchainer.Blockchainer, d dao.DAO) error {
 	return nil
 }
 
-func (n *NEO) updateCache(cvs keysWithVotes, bc blockchainer.Blockchainer) error {
+func (n *NEO) updateCache(cvs keysWithVotes, bc interop.Ledger) error {
 	n.committee.Store(cvs)
 
 	var committee = n.GetCommitteeMembers()
@@ -300,7 +299,7 @@ func (n *NEO) updateCommittee(ic *interop.Context) error {
 }
 
 // ShouldUpdateCommittee returns true if committee is updated at block h.
-func ShouldUpdateCommittee(h uint32, bc blockchainer.Blockchainer) bool {
+func ShouldUpdateCommittee(h uint32, bc interop.Ledger) bool {
 	cfg := bc.GetConfig()
 	r := len(cfg.StandbyCommittee)
 	return h%uint32(r) == 0
@@ -936,7 +935,7 @@ func (n *NEO) getAccountState(ic *interop.Context, args []stackitem.Item) stacki
 }
 
 // ComputeNextBlockValidators returns an actual list of current validators.
-func (n *NEO) ComputeNextBlockValidators(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, error) {
+func (n *NEO) ComputeNextBlockValidators(bc interop.Ledger, d dao.DAO) (keys.PublicKeys, error) {
 	if vals := n.validators.Load().(keys.PublicKeys); vals != nil {
 		return vals.Copy(), nil
 	}
@@ -993,7 +992,7 @@ func toKeysWithVotes(pubs keys.PublicKeys) keysWithVotes {
 }
 
 // computeCommitteeMembers returns public keys of nodes in committee.
-func (n *NEO) computeCommitteeMembers(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, keysWithVotes, error) {
+func (n *NEO) computeCommitteeMembers(bc interop.Ledger, d dao.DAO) (keys.PublicKeys, keysWithVotes, error) {
 	key := []byte{prefixVotersCount}
 	si := d.GetStorageItem(n.ID, key)
 	if si == nil {

pkg/core/notary_test.go

@@ -13,7 +13,6 @@ import (
 	"github.com/nspcc-dev/neo-go/internal/testchain"
 	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/mempool"
 	"github.com/nspcc-dev/neo-go/pkg/core/native/noderoles"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
@@ -135,14 +134,14 @@ func TestNotary(t *testing.T) {
 	require.NoError(t, err)
 
 	bc.SetNotary(ntr1)
-	bc.RegisterPostBlock(func(bc blockchainer.Blockchainer, pool *mempool.Pool, b *block.Block) {
+	bc.RegisterPostBlock(func(f func(*transaction.Transaction, *mempool.Pool, bool) bool, pool *mempool.Pool, b *block.Block) {
 		ntr1.PostPersist()
 	})
 
 	mp1.RunSubscriptions()
-	go ntr1.Run()
+	ntr1.Start()
 	t.Cleanup(func() {
-		ntr1.Stop()
+		ntr1.Shutdown()
 		mp1.StopSubscriptions()
 	})
 

pkg/core/oracle_test.go

@@ -445,14 +445,14 @@ func TestOracleFull(t *testing.T) {
 	bc := initTestChain(t, nil, nil)
 	acc, orc, _, _ := getTestOracle(t, bc, "./testdata/oracle2.json", "two")
 	mp := bc.GetMemPool()
-	orc.OnTransaction = func(tx *transaction.Transaction) { _ = mp.Add(tx, bc) }
+	orc.OnTransaction = func(tx *transaction.Transaction) error { return mp.Add(tx, bc) }
 	bc.SetOracle(orc)
 
 	cs := getOracleContractState(t, util.Uint160{}, 42)
 	require.NoError(t, bc.contracts.Management.PutContractState(bc.dao, cs))
 
 	go bc.Run()
-	go orc.Run()
+	orc.Start()
 	t.Cleanup(orc.Shutdown)
 
 	bc.setNodesByRole(t, true, noderoles.Oracle, keys.PublicKeys{acc.PrivateKey().PublicKey()})
@@ -470,7 +470,7 @@ func TestNotYetRunningOracle(t *testing.T) {
 	bc := initTestChain(t, nil, nil)
 	acc, orc, _, _ := getTestOracle(t, bc, "./testdata/oracle2.json", "two")
 	mp := bc.GetMemPool()
-	orc.OnTransaction = func(tx *transaction.Transaction) { _ = mp.Add(tx, bc) }
+	orc.OnTransaction = func(tx *transaction.Transaction) error { return mp.Add(tx, bc) }
 	bc.SetOracle(orc)
 
 	cs := getOracleContractState(t, util.Uint160{}, 42)
@@ -498,7 +498,7 @@ func TestNotYetRunningOracle(t *testing.T) {
 	ids = []uint64{3}
 	orc.RemoveRequests(ids) // 3 removed from pending -> 2, 4 in pending.
 
-	go orc.Run()
+	orc.Start()
 	t.Cleanup(orc.Shutdown)
 
 	require.Eventually(t, func() bool { return mp.Count() == 2 },
@@ -541,8 +541,9 @@ type responseWithSig struct {
 }
 
 func saveTxToChan(ch chan *transaction.Transaction) oracle.TxCallback {
-	return func(tx *transaction.Transaction) {
+	return func(tx *transaction.Transaction) error {
 		ch <- tx
+		return nil
 	}
 }
 

pkg/core/stateroot/module.go

@@ -6,11 +6,13 @@ import (
 	"fmt"
 	"sync"
 
+	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/mpt"
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
+	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
+	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 	"go.uber.org/atomic"
@@ -18,13 +20,17 @@ import (
 )
 
 type (
+	// VerifierFunc is a function that allows to check witness of account
+	// for Hashable item with GAS limit.
+	VerifierFunc func(util.Uint160, hash.Hashable, *transaction.Witness, int64) (int64, error)
 	// Module represents module for local processing of state roots.
 	Module struct {
-		Store   *storage.MemCachedStore
-		network netmode.Magic
-		mpt     *mpt.Trie
-		bc      blockchainer.Blockchainer
-		log     *zap.Logger
+		Store    *storage.MemCachedStore
+		network  netmode.Magic
+		srInHead bool
+		mpt      *mpt.Trie
+		verifier VerifierFunc
+		log      *zap.Logger
 
 		currentLocal    atomic.Value
 		localHeight     atomic.Uint32
@@ -45,12 +51,13 @@ type (
 )
 
 // NewModule returns new instance of stateroot module.
-func NewModule(bc blockchainer.Blockchainer, log *zap.Logger, s *storage.MemCachedStore) *Module {
+func NewModule(cfg config.ProtocolConfiguration, verif VerifierFunc, log *zap.Logger, s *storage.MemCachedStore) *Module {
 	return &Module{
-		network: bc.GetConfig().Magic,
-		bc:      bc,
-		log:     log,
-		Store:   s,
+		network:  cfg.Magic,
+		srInHead: cfg.StateRootInHeader,
+		verifier: verif,
+		log:      log,
+		Store:    s,
 	}
 }
 
@@ -191,7 +198,7 @@ func (s *Module) UpdateCurrentLocal(mpt *mpt.Trie, sr *state.MPTRoot) {
 	s.mpt = mpt
 	s.currentLocal.Store(sr.Root)
 	s.localHeight.Store(sr.Index)
-	if s.bc.GetConfig().StateRootInHeader {
+	if s.srInHead {
 		s.validatedHeight.Store(sr.Index)
 		updateStateHeightMetric(sr.Index)
 	}
@@ -216,6 +223,6 @@ func (s *Module) verifyWitness(r *state.MPTRoot) error {
 	s.mtx.Lock()
 	h := s.getKeyCacheForHeight(r.Index).validatorsHash
 	s.mtx.Unlock()
-	_, err := s.bc.VerifyWitness(h, r, &r.Witness[0], maxVerificationGAS)
+	_, err := s.verifier(h, r, &r.Witness[0], maxVerificationGAS)
 	return err
 }

pkg/core/stateroot/store.go

@@ -83,7 +83,7 @@ func (s *Module) AddStateRoot(sr *state.MPTRoot) error {
 		return err
 	}
 	s.validatedHeight.Store(sr.Index)
-	if !s.bc.GetConfig().StateRootInHeader {
+	if !s.srInHead {
 		updateStateHeightMetric(sr.Index)
 	}
 	return nil

pkg/core/stateroot_test.go

@@ -80,32 +80,32 @@ func TestStateRoot(t *testing.T) {
 	tmpDir := t.TempDir()
 	w := createAndWriteWallet(t, accs[0], filepath.Join(tmpDir, "w"), "pass")
 	cfg := createStateRootConfig(w.Path(), "pass")
-	srv, err := stateroot.New(cfg, zaptest.NewLogger(t), bc, nil)
+	srv, err := stateroot.New(cfg, bc.stateRoot, zaptest.NewLogger(t), bc, nil)
 	require.NoError(t, err)
-	require.EqualValues(t, 0, srv.CurrentValidatedHeight())
-	r, err := srv.GetStateRoot(bc.BlockHeight())
+	require.EqualValues(t, 0, bc.stateRoot.CurrentValidatedHeight())
+	r, err := bc.stateRoot.GetStateRoot(bc.BlockHeight())
 	require.NoError(t, err)
-	require.Equal(t, r.Root, srv.CurrentLocalStateRoot())
+	require.Equal(t, r.Root, bc.stateRoot.CurrentLocalStateRoot())
 
 	t.Run("invalid message", func(t *testing.T) {
 		require.Error(t, srv.OnPayload(&payload.Extensible{Data: []byte{42}}))
-		require.EqualValues(t, 0, srv.CurrentValidatedHeight())
+		require.EqualValues(t, 0, bc.stateRoot.CurrentValidatedHeight())
 	})
 	t.Run("drop zero index", func(t *testing.T) {
-		r, err := srv.GetStateRoot(0)
+		r, err := bc.stateRoot.GetStateRoot(0)
 		require.NoError(t, err)
 		data, err := testserdes.EncodeBinary(stateroot.NewMessage(stateroot.RootT, r))
 		require.NoError(t, err)
 		require.NoError(t, srv.OnPayload(&payload.Extensible{Data: data}))
-		require.EqualValues(t, 0, srv.CurrentValidatedHeight())
+		require.EqualValues(t, 0, bc.stateRoot.CurrentValidatedHeight())
 	})
 	t.Run("invalid height", func(t *testing.T) {
-		r, err := srv.GetStateRoot(1)
+		r, err := bc.stateRoot.GetStateRoot(1)
 		require.NoError(t, err)
 		r.Index = 10
 		data := testSignStateRoot(t, r, pubs, accs...)
 		require.Error(t, srv.OnPayload(&payload.Extensible{Data: data}))
-		require.EqualValues(t, 0, srv.CurrentValidatedHeight())
+		require.EqualValues(t, 0, bc.stateRoot.CurrentValidatedHeight())
 	})
 	t.Run("invalid signer", func(t *testing.T) {
 		accInv, err := wallet.NewAccount()
@@ -113,21 +113,21 @@ func TestStateRoot(t *testing.T) {
 		pubs := keys.PublicKeys{accInv.PrivateKey().PublicKey()}
 		require.NoError(t, accInv.ConvertMultisig(1, pubs))
 		transferTokenFromMultisigAccount(t, bc, accInv.Contract.ScriptHash(), bc.contracts.GAS.Hash, 1_0000_0000)
-		r, err := srv.GetStateRoot(1)
+		r, err := bc.stateRoot.GetStateRoot(1)
 		require.NoError(t, err)
 		data := testSignStateRoot(t, r, pubs, accInv)
 		err = srv.OnPayload(&payload.Extensible{Data: data})
 		require.True(t, errors.Is(err, ErrWitnessHashMismatch), "got: %v", err)
-		require.EqualValues(t, 0, srv.CurrentValidatedHeight())
+		require.EqualValues(t, 0, bc.stateRoot.CurrentValidatedHeight())
 	})
 
-	r, err = srv.GetStateRoot(updateIndex + 1)
+	r, err = bc.stateRoot.GetStateRoot(updateIndex + 1)
 	require.NoError(t, err)
 	data := testSignStateRoot(t, r, pubs, accs...)
 	require.NoError(t, srv.OnPayload(&payload.Extensible{Data: data}))
-	require.EqualValues(t, 2, srv.CurrentValidatedHeight())
+	require.EqualValues(t, 2, bc.stateRoot.CurrentValidatedHeight())
 
-	r, err = srv.GetStateRoot(updateIndex + 1)
+	r, err = bc.stateRoot.GetStateRoot(updateIndex + 1)
 	require.NoError(t, err)
 	require.NotEqual(t, 0, len(r.Witness))
 	require.Equal(t, h, r.Witness[0].ScriptHash())
@@ -148,14 +148,14 @@ func TestStateRootInitNonZeroHeight(t *testing.T) {
 		tmpDir := t.TempDir()
 		w := createAndWriteWallet(t, accs[0], filepath.Join(tmpDir, "w"), "pass")
 		cfg := createStateRootConfig(w.Path(), "pass")
-		srv, err := stateroot.New(cfg, zaptest.NewLogger(t), bc, nil)
+		srv, err := stateroot.New(cfg, bc.stateRoot, zaptest.NewLogger(t), bc, nil)
 		require.NoError(t, err)
-		r, err := srv.GetStateRoot(2)
+		r, err := bc.stateRoot.GetStateRoot(2)
 		require.NoError(t, err)
 		data := testSignStateRoot(t, r, pubs, accs...)
 		require.NoError(t, srv.OnPayload(&payload.Extensible{Data: data}))
-		require.EqualValues(t, 2, srv.CurrentValidatedHeight())
-		root = srv.CurrentLocalStateRoot()
+		require.EqualValues(t, 2, bc.stateRoot.CurrentValidatedHeight())
+		root = bc.stateRoot.CurrentLocalStateRoot()
 	})
 
 	bc2 := newTestChainWithCustomCfgAndStore(t, st, nil)
@@ -194,12 +194,12 @@ func TestStateRootFull(t *testing.T) {
 
 	var lastValidated atomic.Value
 	var lastHeight atomic.Uint32
-	srv, err := stateroot.New(cfg, zaptest.NewLogger(t), bc, func(ep *payload.Extensible) {
+	srv, err := stateroot.New(cfg, bc.stateRoot, zaptest.NewLogger(t), bc, func(ep *payload.Extensible) {
 		lastHeight.Store(ep.ValidBlockStart)
 		lastValidated.Store(ep)
 	})
 	require.NoError(t, err)
-	srv.Run()
+	srv.Start()
 	t.Cleanup(srv.Shutdown)
 
 	bc.setNodesByRole(t, true, noderoles.StateValidator, pubs)
@@ -211,7 +211,7 @@ func TestStateRootFull(t *testing.T) {
 	require.Eventually(t, func() bool { return lastHeight.Load() == 3 }, time.Second, time.Millisecond)
 	checkVoteBroadcasted(t, bc, lastValidated.Load().(*payload.Extensible), 3, 1)
 
-	r, err := srv.GetStateRoot(2)
+	r, err := bc.stateRoot.GetStateRoot(2)
 	require.NoError(t, err)
 	require.NoError(t, srv.AddSignature(2, 0, accs[0].PrivateKey().SignHashable(uint32(netmode.UnitTestNet), r)))
 	require.NotNil(t, lastValidated.Load().(*payload.Extensible))
@@ -220,7 +220,7 @@ func TestStateRootFull(t *testing.T) {
 	require.NoError(t, testserdes.DecodeBinary(lastValidated.Load().(*payload.Extensible).Data, msg))
 	require.NotEqual(t, stateroot.RootT, msg.Type) // not a sender for this root
 
-	r, err = srv.GetStateRoot(3)
+	r, err = bc.stateRoot.GetStateRoot(3)
 	require.NoError(t, err)
 	require.Error(t, srv.AddSignature(2, 0, accs[0].PrivateKey().SignHashable(uint32(netmode.UnitTestNet), r)))
 	require.NoError(t, srv.AddSignature(3, 0, accs[0].PrivateKey().SignHashable(uint32(netmode.UnitTestNet), r)))

pkg/core/statesync/module.go

@@ -23,10 +23,11 @@ import (
 	"fmt"
 	"sync"
 
+	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/dao"
 	"github.com/nspcc-dev/neo-go/pkg/core/mpt"
+	"github.com/nspcc-dev/neo-go/pkg/core/stateroot"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
 	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/util"
@@ -59,6 +60,16 @@ const (
 	blocksSynced
 )
 
+// Ledger is the interface required from Blockchain for Module to operate.
+type Ledger interface {
+	AddHeaders(...*block.Header) error
+	BlockHeight() uint32
+	GetConfig() config.ProtocolConfiguration
+	GetHeader(hash util.Uint256) (*block.Header, error)
+	GetHeaderHash(int) util.Uint256
+	HeaderHeight() uint32
+}
+
 // Module represents state sync module and aimed to gather state-related data to
 // perform an atomic state jump.
 type Module struct {
@@ -74,9 +85,10 @@ type Module struct {
 	// blockHeight is the index of the latest stored block.
 	blockHeight uint32
 
-	dao     *dao.Simple
-	bc      blockchainer.Blockchainer
-	mptpool *Pool
+	dao      *dao.Simple
+	bc       Ledger
+	stateMod *stateroot.Module
+	mptpool  *Pool
 
 	billet *mpt.Billet
 
@@ -84,17 +96,19 @@ type Module struct {
 }
 
 // NewModule returns new instance of statesync module.
-func NewModule(bc blockchainer.Blockchainer, log *zap.Logger, s *dao.Simple, jumpCallback func(p uint32) error) *Module {
+func NewModule(bc Ledger, stateMod *stateroot.Module, log *zap.Logger, s *dao.Simple, jumpCallback func(p uint32) error) *Module {
 	if !(bc.GetConfig().P2PStateExchangeExtensions && bc.GetConfig().RemoveUntraceableBlocks) {
 		return &Module{
 			dao:       s,
 			bc:        bc,
+			stateMod:  stateMod,
 			syncStage: inactive,
 		}
 	}
 	return &Module{
 		dao:          s,
 		bc:           bc,
+		stateMod:     stateMod,
 		log:          log,
 		syncInterval: uint32(bc.GetConfig().StateSyncInterval),
 		mptpool:      NewPool(),
@@ -146,7 +160,7 @@ func (s *Module) Init(currChainHeight uint32) error {
 		// current chain's state until new state is completely fetched, outdated state-related data
 		// will be removed from storage during (*Blockchain).jumpToState(...) execution.
 		// All we need to do right now is to remove genesis-related MPT nodes.
-		err = s.bc.GetStateModule().CleanStorage()
+		err = s.stateMod.CleanStorage()
 		if err != nil {
 			return fmt.Errorf("failed to remove outdated MPT data from storage: %w", err)
 		}
@@ -201,7 +215,7 @@ func (s *Module) defineSyncStage() error {
 	if s.blockHeight > s.syncPoint {
 		s.syncStage |= mptSynced
 		s.log.Info("MPT is in sync",
-			zap.Uint32("stateroot height", s.bc.GetStateModule().CurrentLocalHeight()))
+			zap.Uint32("stateroot height", s.stateMod.CurrentLocalHeight()))
 	} else if s.syncStage&headersSynced != 0 {
 		header, err := s.bc.GetHeader(s.bc.GetHeaderHash(int(s.syncPoint + 1)))
 		if err != nil {

pkg/neotest/basic.go

@@ -255,7 +255,7 @@ func addSystemFee(bc blockchainer.Blockchainer, tx *transaction.Transaction, sys
 }
 
 func addNetworkFee(bc blockchainer.Blockchainer, tx *transaction.Transaction, signers ...Signer) {
-	baseFee := bc.GetPolicer().GetBaseExecFee()
+	baseFee := bc.GetBaseExecFee()
 	size := io.GetVarSize(tx)
 	for _, sgr := range signers {
 		netFee, sizeDelta := fee.Calculate(baseFee, sgr.Script())
@@ -335,12 +335,12 @@ func TestInvoke(bc blockchainer.Blockchainer, tx *transaction.Transaction) (*vm.
 	// `GetTestVM` as well as `Run` can use transaction hash which will set cached value.
 	// This is unwanted behaviour so we explicitly copy transaction to perform execution.
 	ttx := *tx
-	v, f := bc.GetTestVM(trigger.Application, &ttx, b)
-	defer f()
+	ic := bc.GetTestVM(trigger.Application, &ttx, b)
+	defer ic.Finalize()
 
-	v.LoadWithFlags(tx.Script, callflag.All)
-	err = v.Run()
-	return v, err
+	ic.VM.LoadWithFlags(tx.Script, callflag.All)
+	err = ic.VM.Run()
+	return ic.VM, err
 }
 
 // GetTransaction returns transaction and its height by the specified hash.

pkg/neotest/client.go

@@ -41,12 +41,12 @@ func (e *Executor) ValidatorInvoker(h util.Uint160) *ContractInvoker {
 func (c *ContractInvoker) TestInvoke(t *testing.T, method string, args ...interface{}) (*vm.Stack, error) {
 	tx := c.PrepareInvokeNoSign(t, method, args...)
 	b := c.NewUnsignedBlock(t, tx)
-	v, f := c.Chain.GetTestVM(trigger.Application, tx, b)
-	t.Cleanup(f)
+	ic := c.Chain.GetTestVM(trigger.Application, tx, b)
+	t.Cleanup(ic.Finalize)
 
-	v.LoadWithFlags(tx.Script, callflag.All)
-	err := v.Run()
-	return v.Estack(), err
+	ic.VM.LoadWithFlags(tx.Script, callflag.All)
+	err := ic.VM.Run()
+	return ic.VM.Estack(), err
 }
 
 // WithSigners creates new client with the provided signer.

pkg/network/blockqueue.go

@@ -4,17 +4,23 @@ import (
 	"sync"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"go.uber.org/atomic"
 	"go.uber.org/zap"
 )
 
+// Blockqueuer is the interface for block queue.
+type Blockqueuer interface {
+	AddBlock(block *block.Block) error
+	AddHeaders(...*block.Header) error
+	BlockHeight() uint32
+}
+
 type blockQueue struct {
 	log         *zap.Logger
 	queueLock   sync.Mutex
 	queue       []*block.Block
 	checkBlocks chan struct{}
-	chain       blockchainer.Blockqueuer
+	chain       Blockqueuer
 	relayF      func(*block.Block)
 	discarded   *atomic.Bool
 	len         int
@@ -26,7 +32,7 @@ const (
 	blockCacheSize = 2000
 )
 
-func newBlockQueue(capacity int, bc blockchainer.Blockqueuer, log *zap.Logger, relayer func(*block.Block)) *blockQueue {
+func newBlockQueue(capacity int, bc Blockqueuer, log *zap.Logger, relayer func(*block.Block)) *blockQueue {
 	if log == nil {
 		return nil
 	}

pkg/network/extpool/pool.go

@@ -5,11 +5,19 @@ import (
 	"errors"
 	"sync"
 
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
+	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
+	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
 	"github.com/nspcc-dev/neo-go/pkg/network/payload"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 )
 
+// Ledger is enough of Blockchain to satisfy Pool.
+type Ledger interface {
+	BlockHeight() uint32
+	IsExtensibleAllowed(util.Uint160) bool
+	VerifyWitness(util.Uint160, hash.Hashable, *transaction.Witness, int64) (int64, error)
+}
+
 // Pool represents pool of extensible payloads.
 type Pool struct {
 	lock     sync.RWMutex
@@ -17,11 +25,11 @@ type Pool struct {
 	senders  map[util.Uint160]*list.List
 	// singleCap represents maximum number of payloads from the single sender.
 	singleCap int
-	chain     blockchainer.Blockchainer
+	chain     Ledger
 }
 
 // New returns new payload pool using provided chain.
-func New(bc blockchainer.Blockchainer, capacity int) *Pool {
+func New(bc Ledger, capacity int) *Pool {
 	if capacity <= 0 {
 		panic("invalid capacity")
 	}

pkg/network/extpool/pool_test.go

@@ -4,7 +4,6 @@ import (
 	"errors"
 	"testing"
 
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
 	"github.com/nspcc-dev/neo-go/pkg/network/payload"
@@ -116,7 +115,7 @@ func (p *Pool) testAdd(t *testing.T, expectedOk bool, expectedErr error, ep *pay
 }
 
 type testChain struct {
-	blockchainer.Blockchainer
+	Ledger
 	height        uint32
 	verifyWitness func(util.Uint160) bool
 	isAllowed     func(util.Uint160) bool

pkg/network/helper_test.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/nspcc-dev/neo-go/internal/fakechain"
 	"github.com/nspcc-dev/neo-go/pkg/config"
+	"github.com/nspcc-dev/neo-go/pkg/consensus"
 	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/network/capability"
 	"github.com/nspcc-dev/neo-go/pkg/network/payload"
@@ -192,9 +193,13 @@ func newTestServer(t *testing.T, serverConfig ServerConfig) *Server {
 }
 
 func newTestServerWithCustomCfg(t *testing.T, serverConfig ServerConfig, protocolCfg func(*config.ProtocolConfiguration)) *Server {
-	s, err := newServerFromConstructors(serverConfig, fakechain.NewFakeChainWithCustomCfg(protocolCfg), zaptest.NewLogger(t),
-		newFakeTransp, newFakeConsensus, newTestDiscovery)
+	s, err := newServerFromConstructors(serverConfig, fakechain.NewFakeChainWithCustomCfg(protocolCfg), new(fakechain.FakeStateSync), zaptest.NewLogger(t),
+		newFakeTransp, newTestDiscovery)
 	require.NoError(t, err)
+	if serverConfig.Wallet != nil {
+		cons := new(fakeConsensus)
+		s.AddExtensibleHPService(cons, consensus.Category, cons.OnPayload, cons.OnTransaction)
+	}
 	t.Cleanup(s.discovery.Close)
 	return s
 }

pkg/network/notary_feer.go

@@ -3,13 +3,12 @@ package network
 import (
 	"math/big"
 
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 )
 
 // NotaryFeer implements mempool.Feer interface for Notary balance handling.
 type NotaryFeer struct {
-	bc blockchainer.Blockchainer
+	bc Ledger
 }
 
 // FeePerByte implements mempool.Feer interface.
@@ -33,7 +32,7 @@ func (f NotaryFeer) P2PSigExtensionsEnabled() bool {
 }
 
 // NewNotaryFeer returns new NotaryFeer instance.
-func NewNotaryFeer(bc blockchainer.Blockchainer) NotaryFeer {
+func NewNotaryFeer(bc Ledger) NotaryFeer {
 	return NotaryFeer{
 		bc: bc,
 	}

pkg/network/server.go

@@ -5,6 +5,7 @@ import (
 	"encoding/binary"
 	"errors"
 	"fmt"
+	"math/big"
 	mrand "math/rand"
 	"net"
 	"sort"
@@ -12,10 +13,9 @@ import (
 	"sync"
 	"time"
 
+	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
-	"github.com/nspcc-dev/neo-go/pkg/consensus"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/mempool"
 	"github.com/nspcc-dev/neo-go/pkg/core/mempoolevent"
 	"github.com/nspcc-dev/neo-go/pkg/core/mpt"
@@ -24,9 +24,6 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/network/capability"
 	"github.com/nspcc-dev/neo-go/pkg/network/extpool"
 	"github.com/nspcc-dev/neo-go/pkg/network/payload"
-	"github.com/nspcc-dev/neo-go/pkg/services/notary"
-	"github.com/nspcc-dev/neo-go/pkg/services/oracle"
-	"github.com/nspcc-dev/neo-go/pkg/services/stateroot"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 	"go.uber.org/atomic"
 	"go.uber.org/zap"
@@ -52,6 +49,37 @@ var (
 )
 
 type (
+	// Ledger is everything Server needs from the blockchain.
+	Ledger interface {
+		extpool.Ledger
+		mempool.Feer
+		Blockqueuer
+		GetBlock(hash util.Uint256) (*block.Block, error)
+		GetConfig() config.ProtocolConfiguration
+		GetHeader(hash util.Uint256) (*block.Header, error)
+		GetHeaderHash(int) util.Uint256
+		GetMaxVerificationGAS() int64
+		GetMemPool() *mempool.Pool
+		GetNotaryBalance(acc util.Uint160) *big.Int
+		GetNotaryContractScriptHash() util.Uint160
+		GetNotaryDepositExpiration(acc util.Uint160) uint32
+		GetTransaction(util.Uint256) (*transaction.Transaction, uint32, error)
+		HasBlock(util.Uint256) bool
+		HeaderHeight() uint32
+		P2PSigExtensionsEnabled() bool
+		PoolTx(t *transaction.Transaction, pools ...*mempool.Pool) error
+		PoolTxWithData(t *transaction.Transaction, data interface{}, mp *mempool.Pool, feer mempool.Feer, verificationFunction func(t *transaction.Transaction, data interface{}) error) error
+		RegisterPostBlock(f func(func(*transaction.Transaction, *mempool.Pool, bool) bool, *mempool.Pool, *block.Block))
+		SubscribeForBlocks(ch chan<- *block.Block)
+		UnsubscribeFromBlocks(ch chan<- *block.Block)
+	}
+
+	// Service is a service abstraction (oracle, state root, consensus, etc).
+	Service interface {
+		Start()
+		Shutdown()
+	}
+
 	// Server represents the local Node in the network. Its transport could
 	// be of any kind.
 	Server struct {
@@ -68,15 +96,17 @@ type (
 
 		transport         Transporter
 		discovery         Discoverer
-		chain             blockchainer.Blockchainer
+		chain             Ledger
 		bQueue            *blockQueue
 		bSyncQueue        *blockQueue
-		consensus         consensus.Service
 		mempool           *mempool.Pool
 		notaryRequestPool *mempool.Pool
 		extensiblePool    *extpool.Pool
 		notaryFeer        NotaryFeer
-		notaryModule      *notary.Notary
+		services          []Service
+		extensHandlers    map[string]func(*payload.Extensible) error
+		extensHighPrio    string
+		txCallback        func(*transaction.Transaction)
 
 		txInLock sync.Mutex
 		txInMap  map[util.Uint256]struct{}
@@ -97,9 +127,7 @@ type (
 
 		syncReached *atomic.Bool
 
-		oracle    *oracle.Oracle
-		stateRoot stateroot.Service
-		stateSync blockchainer.StateSync
+		stateSync StateSync
 
 		log *zap.Logger
 	}
@@ -117,15 +145,14 @@ func randomID() uint32 {
 }
 
 // NewServer returns a new Server, initialized with the given configuration.
-func NewServer(config ServerConfig, chain blockchainer.Blockchainer, log *zap.Logger) (*Server, error) {
-	return newServerFromConstructors(config, chain, log, func(s *Server) Transporter {
+func NewServer(config ServerConfig, chain Ledger, stSync StateSync, log *zap.Logger) (*Server, error) {
+	return newServerFromConstructors(config, chain, stSync, log, func(s *Server) Transporter {
 		return NewTCPTransport(s, net.JoinHostPort(s.ServerConfig.Address, strconv.Itoa(int(s.ServerConfig.Port))), s.log)
-	}, consensus.NewService, newDefaultDiscovery)
+	}, newDefaultDiscovery)
 }
 
-func newServerFromConstructors(config ServerConfig, chain blockchainer.Blockchainer, log *zap.Logger,
+func newServerFromConstructors(config ServerConfig, chain Ledger, stSync StateSync, log *zap.Logger,
 	newTransport func(*Server) Transporter,
-	newConsensus func(consensus.Config) (consensus.Service, error),
 	newDiscovery func([]string, time.Duration, Transporter) Discoverer,
 ) (*Server, error) {
 	if log == nil {
@@ -154,91 +181,23 @@ func newServerFromConstructors(config ServerConfig, chain blockchainer.Blockchai
 		extensiblePool:    extpool.New(chain, config.ExtensiblePoolSize),
 		log:               log,
 		transactions:      make(chan *transaction.Transaction, 64),
+		extensHandlers:    make(map[string]func(*payload.Extensible) error),
+		stateSync:         stSync,
 	}
 	if chain.P2PSigExtensionsEnabled() {
 		s.notaryFeer = NewNotaryFeer(chain)
 		s.notaryRequestPool = mempool.New(chain.GetConfig().P2PNotaryRequestPayloadPoolSize, 1, true)
-		chain.RegisterPostBlock(func(bc blockchainer.Blockchainer, txpool *mempool.Pool, _ *block.Block) {
+		chain.RegisterPostBlock(func(isRelevant func(*transaction.Transaction, *mempool.Pool, bool) bool, txpool *mempool.Pool, _ *block.Block) {
 			s.notaryRequestPool.RemoveStale(func(t *transaction.Transaction) bool {
-				return bc.IsTxStillRelevant(t, txpool, true)
+				return isRelevant(t, txpool, true)
 			}, s.notaryFeer)
 		})
-		if config.P2PNotaryCfg.Enabled {
-			cfg := notary.Config{
-				MainCfg: config.P2PNotaryCfg,
-				Chain:   chain,
-				Log:     log,
-			}
-			n, err := notary.NewNotary(cfg, s.network, s.notaryRequestPool, func(tx *transaction.Transaction) error {
-				if err := s.RelayTxn(tx); err != nil {
-					return fmt.Errorf("can't relay completed notary transaction: hash %s, error: %w", tx.Hash().StringLE(), err)
-				}
-				return nil
-			})
-			if err != nil {
-				return nil, fmt.Errorf("failed to create Notary module: %w", err)
-			}
-			s.notaryModule = n
-			chain.SetNotary(n)
-		}
-	} else if config.P2PNotaryCfg.Enabled {
-		return nil, errors.New("P2PSigExtensions are disabled, but Notary service is enabled")
 	}
 	s.bQueue = newBlockQueue(maxBlockBatch, chain, log, func(b *block.Block) {
 		s.tryStartServices()
 	})
 
-	if config.StateRootCfg.Enabled && chain.GetConfig().StateRootInHeader {
-		return nil, errors.New("`StateRootInHeader` should be disabled when state service is enabled")
-	}
-
-	sr, err := stateroot.New(config.StateRootCfg, s.log, chain, s.handleNewPayload)
-	if err != nil {
-		return nil, fmt.Errorf("can't initialize StateRoot service: %w", err)
-	}
-	s.stateRoot = sr
-
-	sSync := chain.GetStateSyncModule()
-	s.stateSync = sSync
-	s.bSyncQueue = newBlockQueue(maxBlockBatch, sSync, log, nil)
-
-	if config.OracleCfg.Enabled {
-		orcCfg := oracle.Config{
-			Log:     log,
-			Network: config.Net,
-			MainCfg: config.OracleCfg,
-			Chain:   chain,
-		}
-		orc, err := oracle.NewOracle(orcCfg)
-		if err != nil {
-			return nil, fmt.Errorf("can't initialize Oracle module: %w", err)
-		}
-		orc.SetOnTransaction(func(tx *transaction.Transaction) {
-			if err := s.RelayTxn(tx); err != nil {
-				orc.Log.Error("can't pool oracle tx",
-					zap.String("hash", tx.Hash().StringLE()),
-					zap.Error(err))
-			}
-		})
-		s.oracle = orc
-		chain.SetOracle(orc)
-	}
-
-	srv, err := newConsensus(consensus.Config{
-		Logger:                log,
-		Broadcast:             s.handleNewPayload,
-		Chain:                 chain,
-		ProtocolConfiguration: chain.GetConfig(),
-		RequestTx:             s.requestTx,
-		Wallet:                config.Wallet,
-
-		TimePerBlock: config.TimePerBlock,
-	})
-	if err != nil {
-		return nil, err
-	}
-
-	s.consensus = srv
+	s.bSyncQueue = newBlockQueue(maxBlockBatch, s.stateSync, log, nil)
 
 	if s.MinPeers < 0 {
 		s.log.Info("bad MinPeers configured, using the default value",
@@ -299,20 +258,13 @@ func (s *Server) Shutdown() {
 	s.log.Info("shutting down server", zap.Int("peers", s.PeerCount()))
 	s.transport.Close()
 	s.discovery.Close()
-	s.consensus.Shutdown()
 	for _, p := range s.getPeers(nil) {
 		p.Disconnect(errServerShutdown)
 	}
 	s.bQueue.discard()
 	s.bSyncQueue.discard()
-	if s.StateRootCfg.Enabled {
-		s.stateRoot.Shutdown()
-	}
-	if s.oracle != nil {
-		s.oracle.Shutdown()
-	}
-	if s.notaryModule != nil {
-		s.notaryModule.Stop()
+	for _, svc := range s.services {
+		svc.Shutdown()
 	}
 	if s.chain.P2PSigExtensionsEnabled() {
 		s.notaryRequestPool.StopSubscriptions()
@@ -320,14 +272,27 @@ func (s *Server) Shutdown() {
 	close(s.quit)
 }
 
-// GetOracle returns oracle module instance.
-func (s *Server) GetOracle() *oracle.Oracle {
-	return s.oracle
+// AddService allows to add a service to be started/stopped by Server.
+func (s *Server) AddService(svc Service) {
+	s.services = append(s.services, svc)
 }
 
-// GetStateRoot returns state root service instance.
-func (s *Server) GetStateRoot() stateroot.Service {
-	return s.stateRoot
+// AddExtensibleService register a service that handles extensible payload of some kind.
+func (s *Server) AddExtensibleService(svc Service, category string, handler func(*payload.Extensible) error) {
+	s.extensHandlers[category] = handler
+	s.AddService(svc)
+}
+
+// AddExtensibleHPService registers a high-priority service that handles extensible payload of some kind.
+func (s *Server) AddExtensibleHPService(svc Service, category string, handler func(*payload.Extensible) error, txCallback func(*transaction.Transaction)) {
+	s.txCallback = txCallback
+	s.extensHighPrio = category
+	s.AddExtensibleService(svc, category, handler)
+}
+
+// GetNotaryPool allows to retrieve notary pool, if it's configured.
+func (s *Server) GetNotaryPool() *mempool.Pool {
+	return s.notaryRequestPool
 }
 
 // UnconnectedPeers returns a list of peers that are in the discovery peer list
@@ -460,20 +425,11 @@ func (s *Server) tryStartServices() {
 
 	if s.IsInSync() && s.syncReached.CAS(false, true) {
 		s.log.Info("node reached synchronized state, starting services")
-		if s.Wallet != nil {
-			s.consensus.Start()
-		}
-		if s.StateRootCfg.Enabled {
-			s.stateRoot.Run()
-		}
-		if s.oracle != nil {
-			go s.oracle.Run()
-		}
 		if s.chain.P2PSigExtensionsEnabled() {
 			s.notaryRequestPool.RunSubscriptions() // WSClient is also a subscriber.
 		}
-		if s.notaryModule != nil {
-			go s.notaryModule.Run()
+		for _, svc := range s.services {
+			svc.Start()
 		}
 	}
 }
@@ -674,7 +630,7 @@ func (s *Server) requestBlocksOrHeaders(p Peer) error {
 		return nil
 	}
 	var (
-		bq              blockchainer.Blockqueuer = s.chain
+		bq              Blockqueuer = s.chain
 		requestMPTNodes bool
 	)
 	if s.stateSync.IsActive() {
@@ -974,25 +930,26 @@ func (s *Server) handleExtensibleCmd(e *payload.Extensible) error {
 	if !ok { // payload is already in cache
 		return nil
 	}
-	switch e.Category {
-	case consensus.Category:
-		s.consensus.OnPayload(e)
-	case stateroot.Category:
-		err := s.stateRoot.OnPayload(e)
+	handler := s.extensHandlers[e.Category]
+	if handler != nil {
+		err = handler(e)
 		if err != nil {
 			return err
 		}
-	default:
-		return errors.New("invalid category")
 	}
+	s.advertiseExtensible(e)
+	return nil
+}
 
+func (s *Server) advertiseExtensible(e *payload.Extensible) {
 	msg := NewMessage(CMDInv, payload.NewInventory(payload.ExtensibleType, []util.Uint256{e.Hash()}))
-	if e.Category == consensus.Category {
+	if e.Category == s.extensHighPrio {
+		// It's high priority because it directly affects consensus process,
+		// even though it's just an inv.
 		s.broadcastHPMessage(msg)
 	} else {
 		s.broadcastMessage(msg)
 	}
-	return nil
 }
 
 // handleTxCmd processes received transaction.
@@ -1008,8 +965,10 @@ func (s *Server) handleTxCmd(tx *transaction.Transaction) error {
 	}
 	s.txInMap[tx.Hash()] = struct{}{}
 	s.txInLock.Unlock()
+	if s.txCallback != nil {
+		s.txCallback(tx)
+	}
 	if s.verifyAndPoolTX(tx) == nil {
-		s.consensus.OnTransaction(tx)
 		s.broadcastTX(tx, nil)
 	}
 	s.txInLock.Lock()
@@ -1041,21 +1000,21 @@ func (s *Server) RelayP2PNotaryRequest(r *payload.P2PNotaryRequest) error {
 
 // verifyAndPoolNotaryRequest verifies NotaryRequest payload and adds it to the payload mempool.
 func (s *Server) verifyAndPoolNotaryRequest(r *payload.P2PNotaryRequest) error {
-	return s.chain.PoolTxWithData(r.FallbackTransaction, r, s.notaryRequestPool, s.notaryFeer, verifyNotaryRequest)
+	return s.chain.PoolTxWithData(r.FallbackTransaction, r, s.notaryRequestPool, s.notaryFeer, s.verifyNotaryRequest)
 }
 
 // verifyNotaryRequest is a function for state-dependant P2PNotaryRequest payload verification which is executed before ordinary blockchain's verification.
-func verifyNotaryRequest(bc blockchainer.Blockchainer, _ *transaction.Transaction, data interface{}) error {
+func (s *Server) verifyNotaryRequest(_ *transaction.Transaction, data interface{}) error {
 	r := data.(*payload.P2PNotaryRequest)
 	payer := r.FallbackTransaction.Signers[1].Account
-	if _, err := bc.VerifyWitness(payer, r, &r.Witness, bc.GetPolicer().GetMaxVerificationGAS()); err != nil {
+	if _, err := s.chain.VerifyWitness(payer, r, &r.Witness, s.chain.GetMaxVerificationGAS()); err != nil {
 		return fmt.Errorf("bad P2PNotaryRequest payload witness: %w", err)
 	}
-	notaryHash := bc.GetNotaryContractScriptHash()
+	notaryHash := s.chain.GetNotaryContractScriptHash()
 	if r.FallbackTransaction.Sender() != notaryHash {
 		return errors.New("P2PNotary contract should be a sender of the fallback transaction")
 	}
-	depositExpiration := bc.GetNotaryDepositExpiration(payer)
+	depositExpiration := s.chain.GetNotaryDepositExpiration(payer)
 	if r.FallbackTransaction.ValidUntilBlock >= depositExpiration {
 		return fmt.Errorf("fallback transaction is valid after deposit is unlocked: ValidUntilBlock is %d, deposit lock expires at %d", r.FallbackTransaction.ValidUntilBlock, depositExpiration)
 	}
@@ -1110,7 +1069,7 @@ func (s *Server) handleGetAddrCmd(p Peer) error {
 // 1. Block range is divided into chunks of payload.MaxHashesCount.
 // 2. Send requests for chunk in increasing order.
 // 3. After all requests were sent, request random height.
-func (s *Server) requestBlocks(bq blockchainer.Blockqueuer, p Peer) error {
+func (s *Server) requestBlocks(bq Blockqueuer, p Peer) error {
 	pl := getRequestBlocksPayload(p, bq.BlockHeight(), &s.lastRequestedBlock)
 	return p.EnqueueP2PMessage(NewMessage(CMDGetBlockByIndex, pl))
 }
@@ -1277,25 +1236,21 @@ func (s *Server) tryInitStateSync() {
 		}
 	}
 }
-func (s *Server) handleNewPayload(p *payload.Extensible) {
+
+// BroadcastExtensible add locally-generated Extensible payload to the pool
+// and advertises it to peers.
+func (s *Server) BroadcastExtensible(p *payload.Extensible) {
 	_, err := s.extensiblePool.Add(p)
 	if err != nil {
 		s.log.Error("created payload is not valid", zap.Error(err))
 		return
 	}
 
-	msg := NewMessage(CMDInv, payload.NewInventory(payload.ExtensibleType, []util.Uint256{p.Hash()}))
-	switch p.Category {
-	case consensus.Category:
-		// It's high priority because it directly affects consensus process,
-		// even though it's just an inv.
-		s.broadcastHPMessage(msg)
-	default:
-		s.broadcastMessage(msg)
-	}
+	s.advertiseExtensible(p)
 }
 
-func (s *Server) requestTx(hashes ...util.Uint256) {
+// RequestTx asks for given transactions from Server peers using GetData message.
+func (s *Server) RequestTx(hashes ...util.Uint256) {
 	if len(hashes) == 0 {
 		return
 	}

pkg/network/server_test.go

@@ -38,12 +38,12 @@ type fakeConsensus struct {
 
 var _ consensus.Service = (*fakeConsensus)(nil)
 
-func newFakeConsensus(c consensus.Config) (consensus.Service, error) {
-	return new(fakeConsensus), nil
+func (f *fakeConsensus) Start()    { f.started.Store(true) }
+func (f *fakeConsensus) Shutdown() { f.stopped.Store(true) }
+func (f *fakeConsensus) OnPayload(p *payload.Extensible) error {
+	f.payloads = append(f.payloads, p)
+	return nil
 }
-func (f *fakeConsensus) Start()                                        { f.started.Store(true) }
-func (f *fakeConsensus) Shutdown()                                     { f.stopped.Store(true) }
-func (f *fakeConsensus) OnPayload(p *payload.Extensible)               { f.payloads = append(f.payloads, p) }
 func (f *fakeConsensus) OnTransaction(tx *transaction.Transaction)     { f.txs = append(f.txs, tx) }
 func (f *fakeConsensus) GetPayload(h util.Uint256) *payload.Extensible { panic("implement me") }
 
@@ -52,7 +52,7 @@ func TestNewServer(t *testing.T) {
 		P2PStateExchangeExtensions: true,
 		StateRootInHeader:          true,
 	}}
-	s, err := newServerFromConstructors(ServerConfig{}, bc, nil, newFakeTransp, newFakeConsensus, newTestDiscovery)
+	s, err := newServerFromConstructors(ServerConfig{}, bc, new(fakechain.FakeStateSync), nil, newFakeTransp, newTestDiscovery)
 	require.Error(t, err)
 
 	t.Run("set defaults", func(t *testing.T) {
@@ -76,13 +76,6 @@ func TestNewServer(t *testing.T) {
 		require.Equal(t, 2, s.ServerConfig.MaxPeers)
 		require.Equal(t, 3, s.ServerConfig.AttemptConnPeers)
 	})
-	t.Run("consensus error is not dropped", func(t *testing.T) {
-		errConsensus := errors.New("can't create consensus")
-		_, err = newServerFromConstructors(ServerConfig{MinPeers: -1}, bc, zaptest.NewLogger(t), newFakeTransp,
-			func(consensus.Config) (consensus.Service, error) { return nil, errConsensus },
-			newTestDiscovery)
-		require.True(t, errors.Is(err, errConsensus), "got: %#v", err)
-	})
 }
 
 func startWithChannel(s *Server) chan error {
@@ -104,13 +97,12 @@ func TestServerStartAndShutdown(t *testing.T) {
 		require.Eventually(t, func() bool { return 1 == s.PeerCount() }, time.Second, time.Millisecond*10)
 
 		assert.True(t, s.transport.(*fakeTransp).started.Load())
-		assert.False(t, s.consensus.(*fakeConsensus).started.Load())
+		assert.Nil(t, s.txCallback)
 
 		s.Shutdown()
 		<-ch
 
 		require.True(t, s.transport.(*fakeTransp).closed.Load())
-		require.True(t, s.consensus.(*fakeConsensus).stopped.Load())
 		err, ok := p.droppedWith.Load().(error)
 		require.True(t, ok)
 		require.True(t, errors.Is(err, errServerShutdown))
@@ -122,12 +114,12 @@ func TestServerStartAndShutdown(t *testing.T) {
 		p := newLocalPeer(t, s)
 		s.register <- p
 
-		assert.True(t, s.consensus.(*fakeConsensus).started.Load())
+		assert.True(t, s.services[0].(*fakeConsensus).started.Load())
 
 		s.Shutdown()
 		<-ch
 
-		require.True(t, s.consensus.(*fakeConsensus).stopped.Load())
+		require.True(t, s.services[0].(*fakeConsensus).stopped.Load())
 	})
 }
 
@@ -416,7 +408,8 @@ func TestBlock(t *testing.T) {
 }
 
 func TestConsensus(t *testing.T) {
-	s := startTestServer(t)
+	s := newTestServer(t, ServerConfig{Wallet: new(config.Wallet)})
+	startWithCleanup(t, s)
 
 	atomic2.StoreUint32(&s.chain.(*fakechain.FakeChain).Blockheight, 4)
 	p := newLocalPeer(t, s)
@@ -438,13 +431,13 @@ func TestConsensus(t *testing.T) {
 
 	s.chain.(*fakechain.FakeChain).VerifyWitnessF = func() (int64, error) { return 0, nil }
 	require.NoError(t, s.handleMessage(p, msg))
-	require.Contains(t, s.consensus.(*fakeConsensus).payloads, msg.Payload.(*payload.Extensible))
+	require.Contains(t, s.services[0].(*fakeConsensus).payloads, msg.Payload.(*payload.Extensible))
 
 	t.Run("small ValidUntilBlockEnd", func(t *testing.T) {
 		t.Run("current height", func(t *testing.T) {
 			msg := newConsensusMessage(0, s.chain.BlockHeight())
 			require.NoError(t, s.handleMessage(p, msg))
-			require.NotContains(t, s.consensus.(*fakeConsensus).payloads, msg.Payload.(*payload.Extensible))
+			require.NotContains(t, s.services[0].(*fakeConsensus).payloads, msg.Payload.(*payload.Extensible))
 		})
 		t.Run("invalid", func(t *testing.T) {
 			msg := newConsensusMessage(0, s.chain.BlockHeight()-1)
@@ -455,17 +448,11 @@ func TestConsensus(t *testing.T) {
 		msg := newConsensusMessage(s.chain.BlockHeight()+1, s.chain.BlockHeight()+2)
 		require.Error(t, s.handleMessage(p, msg))
 	})
-	t.Run("invalid category", func(t *testing.T) {
-		pl := payload.NewExtensible()
-		pl.Category = "invalid"
-		pl.ValidBlockEnd = s.chain.BlockHeight() + 1
-		msg := NewMessage(CMDExtensible, pl)
-		require.Error(t, s.handleMessage(p, msg))
-	})
 }
 
 func TestTransaction(t *testing.T) {
-	s := startTestServer(t)
+	s := newTestServer(t, ServerConfig{Wallet: new(config.Wallet)})
+	startWithCleanup(t, s)
 
 	t.Run("good", func(t *testing.T) {
 		tx := newDummyTx()
@@ -481,15 +468,13 @@ func TestTransaction(t *testing.T) {
 		s.register <- p
 
 		s.testHandleMessage(t, nil, CMDTX, tx)
-		require.Contains(t, s.consensus.(*fakeConsensus).txs, tx)
+		require.Contains(t, s.services[0].(*fakeConsensus).txs, tx)
 	})
 	t.Run("bad", func(t *testing.T) {
 		tx := newDummyTx()
 		s.chain.(*fakechain.FakeChain).PoolTxF = func(*transaction.Transaction) error { return core.ErrInsufficientFunds }
 		s.testHandleMessage(t, nil, CMDTX, tx)
-		for _, ftx := range s.consensus.(*fakeConsensus).txs {
-			require.NotEqual(t, ftx, tx)
-		}
+		require.Contains(t, s.services[0].(*fakeConsensus).txs, tx) // Consensus receives everything.
 	})
 }
 
@@ -907,13 +892,13 @@ func TestRequestTx(t *testing.T) {
 
 	t.Run("no hashes, no message", func(t *testing.T) {
 		actual = nil
-		s.requestTx()
+		s.RequestTx()
 		require.Nil(t, actual)
 	})
 	t.Run("good, small", func(t *testing.T) {
 		actual = nil
 		expected := []util.Uint256{random.Uint256(), random.Uint256()}
-		s.requestTx(expected...)
+		s.RequestTx(expected...)
 		require.Equal(t, expected, actual)
 	})
 	t.Run("good, exactly one chunk", func(t *testing.T) {
@@ -922,7 +907,7 @@ func TestRequestTx(t *testing.T) {
 		for i := range expected {
 			expected[i] = random.Uint256()
 		}
-		s.requestTx(expected...)
+		s.RequestTx(expected...)
 		require.Equal(t, expected, actual)
 	})
 	t.Run("good, multiple chunks", func(t *testing.T) {
@@ -931,7 +916,7 @@ func TestRequestTx(t *testing.T) {
 		for i := range expected {
 			expected[i] = random.Uint256()
 		}
-		s.requestTx(expected...)
+		s.RequestTx(expected...)
 		require.Equal(t, expected, actual)
 	})
 }
@@ -1022,6 +1007,9 @@ func TestVerifyNotaryRequest(t *testing.T) {
 	bc := fakechain.NewFakeChain()
 	bc.MaxVerificationGAS = 10
 	bc.NotaryContractScriptHash = util.Uint160{1, 2, 3}
+	s, err := newServerFromConstructors(ServerConfig{}, bc, new(fakechain.FakeStateSync), zaptest.NewLogger(t), newFakeTransp, newTestDiscovery)
+	require.NoError(t, err)
+	t.Cleanup(s.Shutdown)
 	newNotaryRequest := func() *payload.P2PNotaryRequest {
 		return &payload.P2PNotaryRequest{
 			MainTransaction: &transaction.Transaction{Script: []byte{0, 1, 2}},
@@ -1035,26 +1023,26 @@ func TestVerifyNotaryRequest(t *testing.T) {
 
 	t.Run("bad payload witness", func(t *testing.T) {
 		bc.VerifyWitnessF = func() (int64, error) { return 0, errors.New("bad witness") }
-		require.Error(t, verifyNotaryRequest(bc, nil, newNotaryRequest()))
+		require.Error(t, s.verifyNotaryRequest(nil, newNotaryRequest()))
 	})
 
 	t.Run("bad fallback sender", func(t *testing.T) {
 		bc.VerifyWitnessF = func() (int64, error) { return 0, nil }
 		r := newNotaryRequest()
 		r.FallbackTransaction.Signers[0] = transaction.Signer{Account: util.Uint160{7, 8, 9}}
-		require.Error(t, verifyNotaryRequest(bc, nil, r))
+		require.Error(t, s.verifyNotaryRequest(nil, r))
 	})
 
 	t.Run("expired deposit", func(t *testing.T) {
 		r := newNotaryRequest()
 		bc.NotaryDepositExpiration = r.FallbackTransaction.ValidUntilBlock
-		require.Error(t, verifyNotaryRequest(bc, nil, r))
+		require.Error(t, s.verifyNotaryRequest(nil, r))
 	})
 
 	t.Run("good", func(t *testing.T) {
 		r := newNotaryRequest()
 		bc.NotaryDepositExpiration = r.FallbackTransaction.ValidUntilBlock + 1
-		require.NoError(t, verifyNotaryRequest(bc, nil, r))
+		require.NoError(t, s.verifyNotaryRequest(nil, r))
 	})
 }
 

pkg/network/state_sync.go

@@ -1,4 +1,4 @@
-package blockchainer
+package network
 
 import (
 	"github.com/nspcc-dev/neo-go/pkg/core/mpt"
@@ -8,7 +8,7 @@ import (
 // StateSync represents state sync module.
 type StateSync interface {
 	AddMPTNodes([][]byte) error
-	Blockqueuer // Blockqueuer interface
+	Blockqueuer
 	Init(currChainHeight uint32) error
 	IsActive() bool
 	IsInitialized() bool

pkg/rpc/response/result/block.go

@@ -5,12 +5,16 @@ import (
 	"errors"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 )
 
 type (
+	// LedgerAux is a set of methods needed to construct some outputs.
+	LedgerAux interface {
+		BlockHeight() uint32
+		GetHeaderHash(int) util.Uint256
+	}
 	// Block wrapper used for the representation of
 	// block.Block / block.Base on the RPC Server.
 	Block struct {
@@ -28,7 +32,7 @@ type (
 )
 
 // NewBlock creates a new Block wrapper.
-func NewBlock(b *block.Block, chain blockchainer.Blockchainer) Block {
+func NewBlock(b *block.Block, chain LedgerAux) Block {
 	res := Block{
 		Block: *b,
 		BlockMetadata: BlockMetadata{

pkg/rpc/response/result/block_header.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 )
@@ -20,7 +19,7 @@ type (
 )
 
 // NewHeader creates a new Header wrapper.
-func NewHeader(h *block.Header, chain blockchainer.Blockchainer) Header {
+func NewHeader(h *block.Header, chain LedgerAux) Header {
 	res := Header{
 		Header: *h,
 		BlockMetadata: BlockMetadata{

pkg/rpc/response/result/tx_raw_output.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/util"
@@ -27,7 +26,7 @@ type TransactionMetadata struct {
 }
 
 // NewTransactionOutputRaw returns a new ransactionOutputRaw object.
-func NewTransactionOutputRaw(tx *transaction.Transaction, header *block.Header, appExecResult *state.AppExecResult, chain blockchainer.Blockchainer) TransactionOutputRaw {
+func NewTransactionOutputRaw(tx *transaction.Transaction, header *block.Header, appExecResult *state.AppExecResult, chain LedgerAux) TransactionOutputRaw {
 	result := TransactionOutputRaw{
 		Transaction: *tx,
 	}

pkg/rpc/server/client_test.go

@@ -715,9 +715,9 @@ func TestCreateNEP17TransferTx(t *testing.T) {
 		require.NoError(t, err)
 		require.NoError(t, acc.SignTx(testchain.Network(), tx))
 		require.NoError(t, chain.VerifyTx(tx))
-		v, _ := chain.GetTestVM(trigger.Application, tx, nil)
-		v.LoadScriptWithFlags(tx.Script, callflag.All)
-		require.NoError(t, v.Run())
+		ic := chain.GetTestVM(trigger.Application, tx, nil)
+		ic.VM.LoadScriptWithFlags(tx.Script, callflag.All)
+		require.NoError(t, ic.VM.Run())
 	})
 	t.Run("none scope", func(t *testing.T) {
 		_, err := c.CreateNEP17TransferTx(acc, util.Uint160{}, gasContractHash, 1000, 0, nil, []client.SignerAccount{{
@@ -739,9 +739,9 @@ func TestCreateNEP17TransferTx(t *testing.T) {
 		require.NoError(t, err)
 		require.NoError(t, acc.SignTx(testchain.Network(), tx))
 		require.NoError(t, chain.VerifyTx(tx))
-		v, _ := chain.GetTestVM(trigger.Application, tx, nil)
-		v.LoadScriptWithFlags(tx.Script, callflag.All)
-		require.NoError(t, v.Run())
+		ic := chain.GetTestVM(trigger.Application, tx, nil)
+		ic.VM.LoadScriptWithFlags(tx.Script, callflag.All)
+		require.NoError(t, ic.VM.Run())
 	})
 }
 

pkg/rpc/server/server.go

@@ -620,13 +620,13 @@ func (s *Server) calculateNetworkFee(reqParams request.Params) (interface{}, *re
 		}
 
 		if ef == 0 {
-			ef = s.chain.GetPolicer().GetBaseExecFee()
+			ef = s.chain.GetBaseExecFee()
 		}
 		fee, sizeDelta := fee.Calculate(ef, verificationScript)
 		netFee += fee
 		size += sizeDelta
 	}
-	fee := s.chain.GetPolicer().FeePerByte()
+	fee := s.chain.FeePerByte()
 	netFee += int64(size) * fee
 	return result.NetworkFee{Value: netFee}, nil
 }
@@ -853,19 +853,19 @@ func (s *Server) invokeReadOnly(bw *io.BufBinWriter, h util.Uint160, method stri
 	if err != nil {
 		return nil, nil, err
 	}
-	v, finalize := s.chain.GetTestVM(trigger.Application, tx, b)
-	v.GasLimit = core.HeaderVerificationGasLimit
-	v.LoadScriptWithFlags(script, callflag.All)
-	err = v.Run()
+	ic := s.chain.GetTestVM(trigger.Application, tx, b)
+	ic.VM.GasLimit = core.HeaderVerificationGasLimit
+	ic.VM.LoadScriptWithFlags(script, callflag.All)
+	err = ic.VM.Run()
 	if err != nil {
-		finalize()
+		ic.Finalize()
 		return nil, nil, fmt.Errorf("failed to run `%s` for %s: %w", method, h.StringLE(), err)
 	}
-	if v.Estack().Len() != 1 {
-		finalize()
-		return nil, nil, fmt.Errorf("invalid `%s` return values count: expected 1, got %d", method, v.Estack().Len())
+	if ic.VM.Estack().Len() != 1 {
+		ic.Finalize()
+		return nil, nil, fmt.Errorf("invalid `%s` return values count: expected 1, got %d", method, ic.VM.Estack().Len())
 	}
-	return v.Estack().Pop().Item(), finalize, nil
+	return ic.VM.Estack().Pop().Item(), ic.Finalize, nil
 }
 
 func (s *Server) getTokenBalance(h util.Uint160, acc util.Uint160, id []byte, bw *io.BufBinWriter) (*big.Int, error) {
@@ -1690,38 +1690,32 @@ func (s *Server) runScriptInVM(t trigger.Type, script []byte, contractScriptHash
 	if err != nil {
 		return nil, response.NewInternalServerError("can't create fake block", err)
 	}
-	vm, finalize := s.chain.GetTestVM(t, tx, b)
+	ic := s.chain.GetTestVM(t, tx, b)
 	if verbose {
-		vm.EnableInvocationTree()
+		ic.VM.EnableInvocationTree()
 	}
-	vm.GasLimit = int64(s.config.MaxGasInvoke)
+	ic.VM.GasLimit = int64(s.config.MaxGasInvoke)
 	if t == trigger.Verification {
 		// We need this special case because witnesses verification is not the simple System.Contract.Call,
 		// and we need to define exactly the amount of gas consumed for a contract witness verification.
-		gasPolicy := s.chain.GetPolicer().GetMaxVerificationGAS()
-		if vm.GasLimit > gasPolicy {
-			vm.GasLimit = gasPolicy
+		gasPolicy := s.chain.GetMaxVerificationGAS()
+		if ic.VM.GasLimit > gasPolicy {
+			ic.VM.GasLimit = gasPolicy
 		}
 
-		err := s.chain.InitVerificationVM(vm, func(h util.Uint160) (*state.Contract, error) {
-			res := s.chain.GetContractState(h)
-			if res == nil {
-				return nil, fmt.Errorf("unknown contract: %s", h.StringBE())
-			}
-			return res, nil
-		}, contractScriptHash, &transaction.Witness{InvocationScript: script, VerificationScript: []byte{}})
+		err := s.chain.InitVerificationContext(ic, contractScriptHash, &transaction.Witness{InvocationScript: script, VerificationScript: []byte{}})
 		if err != nil {
 			return nil, response.NewInternalServerError("can't prepare verification VM", err)
 		}
 	} else {
-		vm.LoadScriptWithFlags(script, callflag.All)
+		ic.VM.LoadScriptWithFlags(script, callflag.All)
 	}
-	err = vm.Run()
+	err = ic.VM.Run()
 	var faultException string
 	if err != nil {
 		faultException = err.Error()
 	}
-	return result.NewInvoke(vm, finalize, script, faultException, s.config.MaxIteratorResultItems), nil
+	return result.NewInvoke(ic.VM, ic.Finalize, script, faultException, s.config.MaxIteratorResultItems), nil
 }
 
 // submitBlock broadcasts a raw block over the NEO network.

pkg/rpc/server/server_helper_test.go

@@ -102,7 +102,7 @@ func initClearServerWithServices(t testing.TB, needOracle bool, needNotary bool)
 
 	serverConfig := network.NewServerConfig(cfg)
 	serverConfig.Port = 0
-	server, err := network.NewServer(serverConfig, chain, logger)
+	server, err := network.NewServer(serverConfig, chain, chain.GetStateSyncModule(), logger)
 	require.NoError(t, err)
 	rpcServer := New(chain, cfg.ApplicationConfiguration.RPC, server, orc, logger)
 	errCh := make(chan error, 2)

pkg/rpc/server/server_test.go

@@ -2325,7 +2325,7 @@ func BenchmarkHandleIn(b *testing.B) {
 
 	serverConfig := network.NewServerConfig(cfg)
 	serverConfig.LogLevel = zapcore.FatalLevel
-	server, err := network.NewServer(serverConfig, chain, logger)
+	server, err := network.NewServer(serverConfig, chain, chain.GetStateSyncModule(), logger)
 	require.NoError(b, err)
 	rpcServer := New(chain, cfg.ApplicationConfiguration.RPC, server, orc, logger)
 	defer chain.Close()

pkg/services/notary/node_test.go

@@ -6,7 +6,6 @@ import (
 	"github.com/nspcc-dev/neo-go/internal/fakechain"
 	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/mempool"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/wallet"
@@ -14,7 +13,7 @@ import (
 	"go.uber.org/zap/zaptest"
 )
 
-func getTestNotary(t *testing.T, bc blockchainer.Blockchainer, walletPath, pass string) (*wallet.Account, *Notary, *mempool.Pool) {
+func getTestNotary(t *testing.T, bc Ledger, walletPath, pass string) (*wallet.Account, *Notary, *mempool.Pool) {
 	mainCfg := config.P2PNotary{
 		Enabled: true,
 		UnlockWallet: config.Wallet{

pkg/services/notary/notary.go

@@ -11,7 +11,6 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/mempool"
 	"github.com/nspcc-dev/neo-go/pkg/core/mempoolevent"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
@@ -27,6 +26,16 @@ import (
 )
 
 type (
+	// Ledger is the interface to Blockchain sufficient for Notary.
+	Ledger interface {
+		BlockHeight() uint32
+		GetMaxVerificationGAS() int64
+		GetNotaryContractScriptHash() util.Uint160
+		SubscribeForBlocks(ch chan<- *block.Block)
+		UnsubscribeFromBlocks(ch chan<- *block.Block)
+		VerifyWitness(util.Uint160, hash.Hashable, *transaction.Witness, int64) (int64, error)
+	}
+
 	// Notary represents Notary module.
 	Notary struct {
 		Config Config
@@ -60,7 +69,7 @@ type (
 	// Config represents external configuration for Notary module.
 	Config struct {
 		MainCfg config.P2PNotary
-		Chain   blockchainer.Blockchainer
+		Chain   Ledger
 		Log     *zap.Logger
 	}
 )
@@ -143,12 +152,16 @@ func NewNotary(cfg Config, net netmode.Magic, mp *mempool.Pool, onTransaction fu
 	}, nil
 }
 
-// Run runs Notary module and should be called in a separate goroutine.
-func (n *Notary) Run() {
+// Start runs Notary module in a separate goroutine.
+func (n *Notary) Start() {
 	n.Config.Log.Info("starting notary service")
 	n.Config.Chain.SubscribeForBlocks(n.blocksCh)
 	n.mp.SubscribeForTransactions(n.reqCh)
 	go n.newTxCallbackLoop()
+	go n.mainLoop()
+}
+
+func (n *Notary) mainLoop() {
 	for {
 		select {
 		case <-n.stopCh:
@@ -171,8 +184,8 @@ func (n *Notary) Run() {
 	}
 }
 
-// Stop shutdowns Notary module.
-func (n *Notary) Stop() {
+// Shutdown stops Notary module.
+func (n *Notary) Shutdown() {
 	close(n.stopCh)
 }
 
@@ -227,7 +240,7 @@ func (n *Notary) OnNewRequest(payload *payload.P2PNotaryRequest) {
 		switch r.witnessInfo[i].typ {
 		case Contract:
 			// Need to check even if r.main.Scripts[i].InvocationScript is already filled in.
-			_, err := n.Config.Chain.VerifyWitness(r.main.Signers[i].Account, r.main, &w, n.Config.Chain.GetPolicer().GetMaxVerificationGAS())
+			_, err := n.Config.Chain.VerifyWitness(r.main.Signers[i].Account, r.main, &w, n.Config.Chain.GetMaxVerificationGAS())
 			if err != nil {
 				continue
 			}

pkg/services/oracle/oracle.go

@@ -9,10 +9,12 @@ import (
 
 	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
+	"github.com/nspcc-dev/neo-go/pkg/core/block"
+	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract/trigger"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 	"github.com/nspcc-dev/neo-go/pkg/util/slice"
 	"github.com/nspcc-dev/neo-go/pkg/wallet"
@@ -20,6 +22,17 @@ import (
 )
 
 type (
+	// Ledger is the interface to Blockchain sufficient for Oracle.
+	Ledger interface {
+		BlockHeight() uint32
+		FeePerByte() int64
+		GetBaseExecFee() int64
+		GetConfig() config.ProtocolConfiguration
+		GetMaxVerificationGAS() int64
+		GetTestVM(t trigger.Type, tx *transaction.Transaction, b *block.Block) *interop.Context
+		GetTransaction(util.Uint256) (*transaction.Transaction, uint32, error)
+	}
+
 	// Oracle represents oracle module capable of talking
 	// with the external world.
 	Oracle struct {
@@ -64,7 +77,7 @@ type (
 		Network         netmode.Magic
 		MainCfg         config.OracleConfiguration
 		Client          HTTPClient
-		Chain           blockchainer.Blockchainer
+		Chain           Ledger
 		ResponseHandler Broadcaster
 		OnTransaction   TxCallback
 		URIValidator    URIValidator
@@ -85,7 +98,7 @@ type (
 	defaultResponseHandler struct{}
 
 	// TxCallback executes on new transactions when they are ready to be pooled.
-	TxCallback = func(tx *transaction.Transaction)
+	TxCallback = func(tx *transaction.Transaction) error
 	// URIValidator is used to check if provided URL is valid.
 	URIValidator = func(*url.URL) error
 )
@@ -156,7 +169,7 @@ func NewOracle(cfg Config) (*Oracle, error) {
 		o.ResponseHandler = defaultResponseHandler{}
 	}
 	if o.OnTransaction == nil {
-		o.OnTransaction = func(*transaction.Transaction) {}
+		o.OnTransaction = func(*transaction.Transaction) error { return nil }
 	}
 	if o.URIValidator == nil {
 		o.URIValidator = defaultURIValidator
@@ -170,15 +183,18 @@ func (o *Oracle) Shutdown() {
 	o.getBroadcaster().Shutdown()
 }
 
-// Run runs must be executed in a separate goroutine.
-func (o *Oracle) Run() {
+// Start runs the oracle service in a separate goroutine.
+func (o *Oracle) Start() {
 	o.respMtx.Lock()
 	if o.running {
 		o.respMtx.Unlock()
 		return
 	}
 	o.Log.Info("starting oracle service")
+	go o.start()
+}
 
+func (o *Oracle) start() {
 	o.requestMap <- o.pending // Guaranteed to not block, only AddRequests sends to it.
 	o.pending = nil
 	o.running = true
@@ -236,17 +252,12 @@ func (o *Oracle) UpdateNativeContract(script, resp []byte, h util.Uint160, verif
 	o.verifyOffset = verifyOffset
 }
 
-func (o *Oracle) getOnTransaction() TxCallback {
-	o.mtx.RLock()
-	defer o.mtx.RUnlock()
-	return o.OnTransaction
-}
-
-// SetOnTransaction sets callback to pool and broadcast tx.
-func (o *Oracle) SetOnTransaction(cb TxCallback) {
-	o.mtx.Lock()
-	defer o.mtx.Unlock()
-	o.OnTransaction = cb
+func (o *Oracle) sendTx(tx *transaction.Transaction) {
+	if err := o.OnTransaction(tx); err != nil {
+		o.Log.Error("can't pool oracle tx",
+			zap.String("hash", tx.Hash().StringLE()),
+			zap.Error(err))
+	}
 }
 
 func (o *Oracle) getBroadcaster() Broadcaster {

pkg/services/oracle/request.go

@@ -240,7 +240,7 @@ func (o *Oracle) processRequest(priv *keys.PrivateKey, req request) error {
 
 	o.getBroadcaster().SendResponse(priv, resp, txSig)
 	if ready {
-		o.getOnTransaction()(readyTx)
+		o.sendTx(readyTx)
 	}
 	return nil
 }
@@ -253,7 +253,7 @@ func (o *Oracle) processFailedRequest(priv *keys.PrivateKey, req request) {
 		return
 	} else if incTx.isSent {
 		// Tx was sent but not yet persisted. Try to pool it again.
-		o.getOnTransaction()(incTx.tx)
+		o.sendTx(incTx.tx)
 		return
 	}
 
@@ -271,7 +271,7 @@ func (o *Oracle) processFailedRequest(priv *keys.PrivateKey, req request) {
 
 	o.getBroadcaster().SendResponse(priv, getFailedResponse(req.ID), txSig)
 	if ready {
-		o.getOnTransaction()(readyTx)
+		o.sendTx(readyTx)
 	}
 }
 

pkg/services/oracle/response.go

@@ -6,13 +6,13 @@ import (
 	gio "io"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/fee"
+	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/trigger"
-	"github.com/nspcc-dev/neo-go/pkg/vm"
 	"go.uber.org/zap"
 )
 
@@ -59,7 +59,7 @@ func (o *Oracle) AddResponse(pub *keys.PublicKey, reqID uint64, txSig []byte) {
 	incTx.Unlock()
 
 	if ready {
-		o.getOnTransaction()(readyTx)
+		o.sendTx(readyTx)
 	}
 }
 
@@ -115,7 +115,7 @@ func (o *Oracle) CreateResponseTx(gasForResponse int64, vub uint32, resp *transa
 	}
 	tx.NetworkFee += gasConsumed
 
-	netFee, sizeDelta := fee.Calculate(o.Chain.GetPolicer().GetBaseExecFee(), tx.Scripts[1].VerificationScript)
+	netFee, sizeDelta := fee.Calculate(o.Chain.GetBaseExecFee(), tx.Scripts[1].VerificationScript)
 	tx.NetworkFee += netFee
 	size += sizeDelta
 
@@ -138,24 +138,24 @@ func (o *Oracle) testVerify(tx *transaction.Transaction) (int64, bool) {
 	// method caches transaction hash, but tx building is not yet completed and hash will be changed.
 	// So make a copy of tx to avoid wrong hash caching.
 	cp := *tx
-	v, finalize := o.Chain.GetTestVM(trigger.Verification, &cp, nil)
-	v.GasLimit = o.Chain.GetPolicer().GetMaxVerificationGAS()
-	v.LoadScriptWithHash(o.oracleScript, o.oracleHash, callflag.ReadOnly)
-	v.Context().Jump(o.verifyOffset)
+	ic := o.Chain.GetTestVM(trigger.Verification, &cp, nil)
+	ic.VM.GasLimit = o.Chain.GetMaxVerificationGAS()
+	ic.VM.LoadScriptWithHash(o.oracleScript, o.oracleHash, callflag.ReadOnly)
+	ic.VM.Context().Jump(o.verifyOffset)
 
-	ok := isVerifyOk(v, finalize)
-	return v.GasConsumed(), ok
+	ok := isVerifyOk(ic)
+	return ic.VM.GasConsumed(), ok
 }
 
-func isVerifyOk(v *vm.VM, finalize func()) bool {
-	defer finalize()
-	if err := v.Run(); err != nil {
+func isVerifyOk(ic *interop.Context) bool {
+	defer ic.Finalize()
+	if err := ic.VM.Run(); err != nil {
 		return false
 	}
-	if v.Estack().Len() != 1 {
+	if ic.VM.Estack().Len() != 1 {
 		return false
 	}
-	ok, err := v.Estack().Pop().Item().TryBool()
+	ok, err := ic.VM.Estack().Pop().Item().TryBool()
 	return err == nil && ok
 }
 

pkg/services/stateroot/service.go

@@ -8,7 +8,6 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
-	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/stateroot"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
@@ -19,19 +18,26 @@ import (
 )
 
 type (
+	// Ledger is the interface to Blockchain sufficient for Service.
+	Ledger interface {
+		GetConfig() config.ProtocolConfiguration
+		HeaderHeight() uint32
+		SubscribeForBlocks(ch chan<- *block.Block)
+		UnsubscribeFromBlocks(ch chan<- *block.Block)
+	}
+
 	// Service represents state root service.
 	Service interface {
-		blockchainer.StateRoot
 		OnPayload(p *payload.Extensible) error
 		AddSignature(height uint32, validatorIndex int32, sig []byte) error
 		GetConfig() config.StateRoot
-		Run()
+		Start()
 		Shutdown()
 	}
 
 	service struct {
-		blockchainer.StateRoot
-		chain blockchainer.Blockchainer
+		*stateroot.Module
+		chain Ledger
 
 		MainCfg config.StateRoot
 		Network netmode.Magic
@@ -60,10 +66,10 @@ const (
 )
 
 // New returns new state root service instance using underlying module.
-func New(cfg config.StateRoot, log *zap.Logger, bc blockchainer.Blockchainer, cb RelayCallback) (Service, error) {
+func New(cfg config.StateRoot, sm *stateroot.Module, log *zap.Logger, bc Ledger, cb RelayCallback) (Service, error) {
 	bcConf := bc.GetConfig()
 	s := &service{
-		StateRoot:       bc.GetStateModule(),
+		Module:          sm,
 		Network:         bcConf.Magic,
 		chain:           bc,
 		log:             log,
@@ -77,6 +83,9 @@ func New(cfg config.StateRoot, log *zap.Logger, bc blockchainer.Blockchainer, cb
 
 	s.MainCfg = cfg
 	if cfg.Enabled {
+		if bcConf.StateRootInHeader {
+			return nil, errors.New("`StateRootInHeader` should be disabled when state service is enabled")
+		}
 		var err error
 		w := cfg.UnlockWallet
 		if s.wallet, err = wallet.NewWalletFromFile(w.Path); err != nil {

pkg/services/stateroot/validators.go

@@ -17,8 +17,8 @@ const (
 	firstVoteResendDelay = 3 * time.Second
 )
 
-// Run runs service instance in a separate goroutine.
-func (s *service) Run() {
+// Start runs service instance in a separate goroutine.
+func (s *service) Start() {
 	s.log.Info("starting state validation service")
 	s.chain.SubscribeForBlocks(s.blockCh)
 	go s.run()