rpcsrv: don't init Oracle in New, drop oracle dependency

The only thing rpcsrv needs is AddResponse callback.

pkg/services/oracle/broadcaster/oracle.go

@@ -10,7 +10,6 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/rpcclient"
 	"github.com/nspcc-dev/neo-go/pkg/services/helpers/rpcbroadcaster"
-	"github.com/nspcc-dev/neo-go/pkg/services/oracle"
 	"go.uber.org/zap"
 )
 
@@ -20,16 +19,17 @@ const (
 	defaultChanCapacity = 16
 )
 
-type oracleBroadcaster struct {
+// OracleBroadcaster is an oracle broadcaster implementation.
+type OracleBroadcaster struct {
 	rpcbroadcaster.RPCBroadcaster
 }
 
 // New returns a new struct capable of broadcasting oracle responses.
-func New(cfg config.OracleConfiguration, log *zap.Logger) oracle.Broadcaster {
+func New(cfg config.OracleConfiguration, log *zap.Logger) *OracleBroadcaster {
 	if cfg.ResponseTimeout == 0 {
 		cfg.ResponseTimeout = defaultSendTimeout
 	}
-	r := &oracleBroadcaster{
+	r := &OracleBroadcaster{
 		RPCBroadcaster: *rpcbroadcaster.NewRPCBroadcaster(log, cfg.ResponseTimeout),
 	}
 	for i := range cfg.Nodes {
@@ -40,7 +40,7 @@ func New(cfg config.OracleConfiguration, log *zap.Logger) oracle.Broadcaster {
 }
 
 // SendResponse implements interfaces.Broadcaster.
-func (r *oracleBroadcaster) SendResponse(priv *keys.PrivateKey, resp *transaction.OracleResponse, txSig []byte) {
+func (r *OracleBroadcaster) SendResponse(priv *keys.PrivateKey, resp *transaction.OracleResponse, txSig []byte) {
 	pub := priv.PublicKey()
 	data := GetMessage(pub.Bytes(), resp.ID, txSig)
 	msgSig := priv.Sign(data)

pkg/services/oracle/oracle.go

@@ -13,6 +13,7 @@ import (
 	"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/services/oracle/broadcaster"
 	"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"
@@ -43,9 +44,6 @@ type (
 		oracleScript   []byte
 		verifyOffset   int
 
-		// mtx protects setting callbacks.
-		mtx sync.RWMutex
-
 		// accMtx protects account and oracle nodes.
 		accMtx             sync.RWMutex
 		currAccount        *wallet.Account
@@ -94,8 +92,6 @@ type (
 		Shutdown()
 	}
 
-	defaultResponseHandler struct{}
-
 	// TxCallback executes on new transactions when they are ready to be pooled.
 	TxCallback = func(tx *transaction.Transaction) error
 )
@@ -165,7 +161,7 @@ func NewOracle(cfg Config) (*Oracle, error) {
 	}
 
 	if o.ResponseHandler == nil {
-		o.ResponseHandler = defaultResponseHandler{}
+		o.ResponseHandler = broadcaster.New(cfg.MainCfg, cfg.Log)
 	}
 	if o.OnTransaction == nil {
 		o.OnTransaction = func(*transaction.Transaction) error { return nil }
@@ -192,7 +188,7 @@ func (o *Oracle) Shutdown() {
 	}
 	o.running = false
 	close(o.close)
-	o.getBroadcaster().Shutdown()
+	o.ResponseHandler.Shutdown()
 	<-o.done
 }
 
@@ -217,6 +213,7 @@ func (o *Oracle) start() {
 	for i := 0; i < o.MainCfg.MaxConcurrentRequests; i++ {
 		go o.runRequestWorker()
 	}
+	go o.ResponseHandler.Run()
 
 	tick := time.NewTicker(o.MainCfg.RefreshInterval)
 main:
@@ -284,28 +281,3 @@ func (o *Oracle) sendTx(tx *transaction.Transaction) {
 			zap.Error(err))
 	}
 }
-
-func (o *Oracle) getBroadcaster() Broadcaster {
-	o.mtx.RLock()
-	defer o.mtx.RUnlock()
-	return o.ResponseHandler
-}
-
-// SetBroadcaster sets callback to broadcast response.
-func (o *Oracle) SetBroadcaster(b Broadcaster) {
-	o.mtx.Lock()
-	defer o.mtx.Unlock()
-	o.ResponseHandler.Shutdown()
-	o.ResponseHandler = b
-	go b.Run()
-}
-
-// SendResponse implements Broadcaster interface.
-func (defaultResponseHandler) SendResponse(*keys.PrivateKey, *transaction.OracleResponse, []byte) {
-}
-
-// Run implements Broadcaster interface.
-func (defaultResponseHandler) Run() {}
-
-// Shutdown implements Broadcaster interface.
-func (defaultResponseHandler) Shutdown() {}

pkg/services/oracle/request.go

@@ -234,7 +234,7 @@ func (o *Oracle) processRequest(priv *keys.PrivateKey, req request) error {
 	incTx.attempts++
 	incTx.Unlock()
 
-	o.getBroadcaster().SendResponse(priv, resp, txSig)
+	o.ResponseHandler.SendResponse(priv, resp, txSig)
 	if ready {
 		o.sendTx(readyTx)
 	}
@@ -265,7 +265,7 @@ func (o *Oracle) processFailedRequest(priv *keys.PrivateKey, req request) {
 	txSig := incTx.backupSigs[string(priv.PublicKey().Bytes())].sig
 	incTx.Unlock()
 
-	o.getBroadcaster().SendResponse(priv, getFailedResponse(req.ID), txSig)
+	o.ResponseHandler.SendResponse(priv, getFailedResponse(req.ID), txSig)
 	if ready {
 		o.sendTx(readyTx)
 	}

pkg/services/rpcsrv/server.go

@@ -43,7 +43,6 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/neorpc/result"
 	"github.com/nspcc-dev/neo-go/pkg/network"
 	"github.com/nspcc-dev/neo-go/pkg/network/payload"
-	"github.com/nspcc-dev/neo-go/pkg/services/oracle"
 	"github.com/nspcc-dev/neo-go/pkg/services/oracle/broadcaster"
 	"github.com/nspcc-dev/neo-go/pkg/services/rpcsrv/params"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
@@ -108,6 +107,11 @@ type (
 		mempool.Feer // fee interface
 	}
 
+	// OracleHandler is the interface oracle service needs to provide for the Server.
+	OracleHandler interface {
+		AddResponse(pub *keys.PublicKey, reqID uint64, txSig []byte)
+	}
+
 	// Server represents the JSON-RPC 2.0 server.
 	Server struct {
 		*http.Server
@@ -118,7 +122,7 @@ type (
 		network          netmode.Magic
 		stateRootEnabled bool
 		coreServer       *network.Server
-		oracle           *oracle.Oracle
+		oracle           OracleHandler
 		log              *zap.Logger
 		https            *http.Server
 		shutdown         chan struct{}
@@ -248,7 +252,7 @@ var upgrader = websocket.Upgrader{}
 
 // New creates a new Server struct.
 func New(chain Ledger, conf config.RPC, coreServer *network.Server,
-	orc *oracle.Oracle, log *zap.Logger, errChan chan error) Server {
+	orc OracleHandler, log *zap.Logger, errChan chan error) Server {
 	httpServer := &http.Server{
 		Addr: conf.Address + ":" + strconv.FormatUint(uint64(conf.Port), 10),
 	}
@@ -260,9 +264,6 @@ func New(chain Ledger, conf config.RPC, coreServer *network.Server,
 		}
 	}
 
-	if orc != nil {
-		orc.SetBroadcaster(broadcaster.New(orc.MainCfg, log))
-	}
 	protoCfg := chain.GetConfig()
 	if conf.SessionEnabled {
 		if conf.SessionExpirationTime <= 0 {