rpc: allow to track notary requests via Notification subsystem

pkg/rpc/server/server.go

@@ -21,6 +21,7 @@ import (
 	"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/fee"
+	"github.com/nspcc-dev/neo-go/pkg/core/mempoolevent"
 	"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/transaction"
@@ -57,16 +58,18 @@ type (
 		https            *http.Server
 		shutdown         chan struct{}
 
-		subsLock         sync.RWMutex
-		subscribers      map[*subscriber]bool
-		blockSubs        int
-		executionSubs    int
-		notificationSubs int
-		transactionSubs  int
-		blockCh          chan *block.Block
-		executionCh      chan *state.AppExecResult
-		notificationCh   chan *state.NotificationEvent
-		transactionCh    chan *transaction.Transaction
+		subsLock          sync.RWMutex
+		subscribers       map[*subscriber]bool
+		blockSubs         int
+		executionSubs     int
+		notificationSubs  int
+		transactionSubs   int
+		notaryRequestSubs int
+		blockCh           chan *block.Block
+		executionCh       chan *state.AppExecResult
+		notificationCh    chan *state.NotificationEvent
+		transactionCh     chan *transaction.Transaction
+		notaryRequestCh   chan mempoolevent.Event
 	}
 )
 
@@ -174,10 +177,11 @@ func New(chain blockchainer.Blockchainer, conf rpc.Config, coreServer *network.S
 
 		subscribers: make(map[*subscriber]bool),
 		// These are NOT buffered to preserve original order of events.
-		blockCh:        make(chan *block.Block),
-		executionCh:    make(chan *state.AppExecResult),
-		notificationCh: make(chan *state.NotificationEvent),
-		transactionCh:  make(chan *transaction.Transaction),
+		blockCh:         make(chan *block.Block),
+		executionCh:     make(chan *state.AppExecResult),
+		notificationCh:  make(chan *state.NotificationEvent),
+		transactionCh:   make(chan *transaction.Transaction),
+		notaryRequestCh: make(chan mempoolevent.Event),
 	}
 }
 
@@ -1448,6 +1452,9 @@ func (s *Server) subscribe(reqParams request.Params, sub *subscriber) (interface
 	if err != nil || event == response.MissedEventID {
 		return nil, response.ErrInvalidParams
 	}
+	if event == response.NotaryRequestEventID && !s.chain.P2PSigExtensionsEnabled() {
+		return nil, response.WrapErrorWithData(response.ErrInvalidParams, errors.New("P2PSigExtensions are disabled"))
+	}
 	// Optional filter.
 	var filter interface{}
 	if p := reqParams.Value(1); p != nil {
@@ -1468,6 +1475,10 @@ func (s *Server) subscribe(reqParams request.Params, sub *subscriber) (interface
 			if p.Type != request.ExecutionFilterT {
 				return nil, response.ErrInvalidParams
 			}
+		case response.NotaryRequestEventID:
+			if p.Type != request.TxFilterT {
+				return nil, response.ErrInvalidParams
+			}
 		}
 		filter = p.Value
 	}
@@ -1519,6 +1530,11 @@ func (s *Server) subscribeToChannel(event response.EventID) {
 			s.chain.SubscribeForExecutions(s.executionCh)
 		}
 		s.executionSubs++
+	case response.NotaryRequestEventID:
+		if s.notaryRequestSubs == 0 {
+			s.coreServer.SubscribeForNotaryRequests(s.notaryRequestCh)
+		}
+		s.notaryRequestSubs++
 	}
 }
 
@@ -1565,6 +1581,11 @@ func (s *Server) unsubscribeFromChannel(event response.EventID) {
 		if s.executionSubs == 0 {
 			s.chain.UnsubscribeFromExecutions(s.executionCh)
 		}
+	case response.NotaryRequestEventID:
+		s.notaryRequestSubs--
+		if s.notaryRequestSubs == 0 {
+			s.coreServer.UnsubscribeFromNotaryRequests(s.notaryRequestCh)
+		}
 	}
 }
 
@@ -1605,6 +1626,12 @@ chloop:
 		case tx := <-s.transactionCh:
 			resp.Event = response.TransactionEventID
 			resp.Payload[0] = tx
+		case e := <-s.notaryRequestCh:
+			resp.Event = response.NotaryRequestEventID
+			resp.Payload[0] = &response.NotaryRequestEvent{
+				Type:          e.Type,
+				NotaryRequest: e.Data.(*payload.P2PNotaryRequest),
+			}
 		}
 		s.subsLock.RLock()
 	subloop:
@@ -1657,6 +1684,9 @@ chloop:
 	s.chain.UnsubscribeFromTransactions(s.transactionCh)
 	s.chain.UnsubscribeFromNotifications(s.notificationCh)
 	s.chain.UnsubscribeFromExecutions(s.executionCh)
+	if s.chain.P2PSigExtensionsEnabled() {
+		s.coreServer.UnsubscribeFromNotaryRequests(s.notaryRequestCh)
+	}
 	s.subsLock.Unlock()
 drainloop:
 	for {
@@ -1665,6 +1695,7 @@ drainloop:
 		case <-s.executionCh:
 		case <-s.notificationCh:
 		case <-s.transactionCh:
+		case <-s.notaryRequestCh:
 		default:
 			break drainloop
 		}
@@ -1675,6 +1706,7 @@ drainloop:
 	close(s.transactionCh)
 	close(s.notificationCh)
 	close(s.executionCh)
+	close(s.notaryRequestCh)
 }
 
 func (s *Server) blockHeightFromParam(param *request.Param) (int, *response.Error) {