rpc: allow to track notary requests via Notification subsystem

pkg/network/payload/notary_request.go

@@ -13,8 +13,8 @@ import (
 
 // P2PNotaryRequest contains main and fallback transactions for the Notary service.
 type P2PNotaryRequest struct {
-	MainTransaction     *transaction.Transaction
+	MainTransaction     *transaction.Transaction `json:"maintx"`
-	FallbackTransaction *transaction.Transaction
+	FallbackTransaction *transaction.Transaction `json:"fallbacktx"`
 
 	Witness transaction.Witness
 

pkg/network/server.go

@@ -16,6 +16,7 @@ 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/mempool"
+	"github.com/nspcc-dev/neo-go/pkg/core/mempoolevent"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/network/capability"
 	"github.com/nspcc-dev/neo-go/pkg/network/extpool"
@@ -143,7 +144,7 @@ func newServerFromConstructors(config ServerConfig, chain blockchainer.Blockchai
 	}
 	if chain.P2PSigExtensionsEnabled() {
 		s.notaryFeer = NewNotaryFeer(chain)
-		s.notaryRequestPool = mempool.New(chain.GetConfig().P2PNotaryRequestPayloadPoolSize, 1, config.P2PNotaryCfg.Enabled)
+		s.notaryRequestPool = mempool.New(chain.GetConfig().P2PNotaryRequestPayloadPoolSize, 1, true)
 		chain.RegisterPostBlock(func(bc blockchainer.Blockchainer, txpool *mempool.Pool, _ *block.Block) {
 			s.notaryRequestPool.RemoveStale(func(t *transaction.Transaction) bool {
 				return bc.IsTxStillRelevant(t, txpool, true)
@@ -295,6 +296,8 @@ func (s *Server) Shutdown() {
 	}
 	if s.notaryModule != nil {
 		s.notaryModule.Stop()
+	}
+	if s.chain.P2PSigExtensionsEnabled() {
 		s.notaryRequestPool.StopSubscriptions()
 	}
 	close(s.quit)
@@ -449,13 +452,39 @@ func (s *Server) tryStartServices() {
 		if s.oracle != nil {
 			go s.oracle.Run()
 		}
+		if s.chain.P2PSigExtensionsEnabled() {
+			s.notaryRequestPool.RunSubscriptions() // WSClient is also a subscriber.
+		}
 		if s.notaryModule != nil {
-			s.notaryRequestPool.RunSubscriptions()
 			go s.notaryModule.Run()
 		}
 	}
 }
 
+// SubscribeForNotaryRequests adds given channel to a notary request event
+// broadcasting, so when a new P2PNotaryRequest is received or an existing
+// P2PNotaryRequest is removed from pool you'll receive it via this channel.
+// Make sure it's read from regularly as not reading these events might affect
+// other Server functions.
+// Ensure that P2PSigExtensions are enabled before calling this method.
+func (s *Server) SubscribeForNotaryRequests(ch chan<- mempoolevent.Event) {
+	if !s.chain.P2PSigExtensionsEnabled() {
+		panic("P2PSigExtensions are disabled")
+	}
+	s.notaryRequestPool.SubscribeForTransactions(ch)
+}
+
+// UnsubscribeFromNotaryRequests unsubscribes given channel from notary request
+// notifications, you can close it afterwards. Passing non-subscribed channel
+// is a no-op.
+// Ensure that P2PSigExtensions are enabled before calling this method.
+func (s *Server) UnsubscribeFromNotaryRequests(ch chan<- mempoolevent.Event) {
+	if !s.chain.P2PSigExtensionsEnabled() {
+		panic("P2PSigExtensions are disabled")
+	}
+	s.notaryRequestPool.UnsubscribeFromTransactions(ch)
+}
+
 // Peers returns the current list of peers connected to
 // the server.
 func (s *Server) Peers() map[Peer]bool {

pkg/rpc/client/wsclient.go

@@ -149,6 +149,8 @@ readloop:
 				val = new(state.NotificationEvent)
 			case response.ExecutionEventID:
 				val = new(state.AppExecResult)
+			case response.NotaryRequestEventID:
+				val = new(response.NotaryRequestEvent)
 			case response.MissedEventID:
 				// No value.
 			default:
@@ -300,6 +302,18 @@ func (c *WSClient) SubscribeForTransactionExecutions(state *string) (string, err
 	return c.performSubscription(params)
 }
 
+// SubscribeForNotaryRequests adds subscription for notary request payloads
+// addition or removal events to this instance of client. It can be filtered by
+// request sender's hash, or main tx signer's hash, nil value puts no such
+// restrictions.
+func (c *WSClient) SubscribeForNotaryRequests(sender *util.Uint160, mainSigner *util.Uint160) (string, error) {
+	params := request.NewRawParams("notary_request_event")
+	if sender != nil {
+		params.Values = append(params.Values, request.TxFilter{Sender: sender, Signer: mainSigner})
+	}
+	return c.performSubscription(params)
+}
+
 // Unsubscribe removes subscription for given event stream.
 func (c *WSClient) Unsubscribe(id string) error {
 	return c.performUnsubscription(id)

pkg/rpc/response/events.go

@@ -3,11 +3,20 @@ package response
 import (
 	"encoding/json"
 	"errors"
+
+	"github.com/nspcc-dev/neo-go/pkg/core/mempoolevent"
+	"github.com/nspcc-dev/neo-go/pkg/network/payload"
 )
 
 type (
 	// EventID represents an event type happening on the chain.
 	EventID byte
+	// NotaryRequestEvent represents P2PNotaryRequest event either added or removed
+	// from notary payload pool.
+	NotaryRequestEvent struct {
+		Type          mempoolevent.Type         `json:"type"`
+		NotaryRequest *payload.P2PNotaryRequest `json:"notaryrequest"`
+	}
 )
 
 const (
@@ -22,6 +31,8 @@ const (
 	NotificationEventID
 	// ExecutionEventID is used for `transaction_executed` events.
 	ExecutionEventID
+	// NotaryRequestEventID is used for `notary_request_event` event.
+	NotaryRequestEventID
 	// MissedEventID notifies user of missed events.
 	MissedEventID EventID = 255
 )
@@ -37,6 +48,8 @@ func (e EventID) String() string {
 		return "notification_from_execution"
 	case ExecutionEventID:
 		return "transaction_executed"
+	case NotaryRequestEventID:
+		return "notary_request_event"
 	case MissedEventID:
 		return "event_missed"
 	default:
@@ -55,6 +68,8 @@ func GetEventIDFromString(s string) (EventID, error) {
 		return NotificationEventID, nil
 	case "transaction_executed":
 		return ExecutionEventID, nil
+	case "notary_request_event":
+		return NotaryRequestEventID, nil
 	case "event_missed":
 		return MissedEventID, nil
 	default:

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
+		subsLock          sync.RWMutex
-		subscribers      map[*subscriber]bool
+		subscribers       map[*subscriber]bool
-		blockSubs        int
+		blockSubs         int
-		executionSubs    int
+		executionSubs     int
-		notificationSubs int
+		notificationSubs  int
-		transactionSubs  int
+		transactionSubs   int
-		blockCh          chan *block.Block
+		notaryRequestSubs int
-		executionCh      chan *state.AppExecResult
+		blockCh           chan *block.Block
-		notificationCh   chan *state.NotificationEvent
+		executionCh       chan *state.AppExecResult
-		transactionCh    chan *transaction.Transaction
+		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),
+		blockCh:         make(chan *block.Block),
-		executionCh:    make(chan *state.AppExecResult),
+		executionCh:     make(chan *state.AppExecResult),
-		notificationCh: make(chan *state.NotificationEvent),
+		notificationCh:  make(chan *state.NotificationEvent),
-		transactionCh:  make(chan *transaction.Transaction),
+		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) {

pkg/rpc/server/server_test.go

@@ -1107,42 +1107,7 @@ func TestSubmitNotaryRequest(t *testing.T) {
 	})
 	t.Run("valid request", func(t *testing.T) {
 		sender := testchain.PrivateKeyByID(0) // owner of the deposit in testchain
-		mainTx := &transaction.Transaction{
+		p := createValidNotaryRequest(chain, sender, 1)
-			Attributes:      []transaction.Attribute{{Type: transaction.NotaryAssistedT, Value: &transaction.NotaryAssisted{NKeys: 1}}},
-			Script:          []byte{byte(opcode.RET)},
-			ValidUntilBlock: 123,
-			Signers:         []transaction.Signer{{Account: util.Uint160{1, 5, 9}}},
-			Scripts: []transaction.Witness{{
-				InvocationScript:   []byte{1, 4, 7},
-				VerificationScript: []byte{3, 6, 9},
-			}},
-		}
-		fallbackTx := &transaction.Transaction{
-			Script:          []byte{byte(opcode.RET)},
-			ValidUntilBlock: 123,
-			Attributes: []transaction.Attribute{
-				{Type: transaction.NotValidBeforeT, Value: &transaction.NotValidBefore{Height: 123}},
-				{Type: transaction.ConflictsT, Value: &transaction.Conflicts{Hash: mainTx.Hash()}},
-				{Type: transaction.NotaryAssistedT, Value: &transaction.NotaryAssisted{NKeys: 0}},
-			},
-			Signers: []transaction.Signer{{Account: chain.GetNotaryContractScriptHash()}, {Account: sender.GetScriptHash()}},
-			Scripts: []transaction.Witness{
-				{InvocationScript: append([]byte{byte(opcode.PUSHDATA1), 64}, make([]byte, 64)...), VerificationScript: []byte{}},
-			},
-			NetworkFee: 2_0000_0000,
-		}
-		fallbackTx.Scripts = append(fallbackTx.Scripts, transaction.Witness{
-			InvocationScript:   append([]byte{byte(opcode.PUSHDATA1), 64}, sender.SignHashable(uint32(testchain.Network()), fallbackTx)...),
-			VerificationScript: sender.PublicKey().GetVerificationScript(),
-		})
-		p := &payload.P2PNotaryRequest{
-			MainTransaction:     mainTx,
-			FallbackTransaction: fallbackTx,
-		}
-		p.Witness = transaction.Witness{
-			InvocationScript:   append([]byte{byte(opcode.PUSHDATA1), 64}, sender.SignHashable(uint32(testchain.Network()), p)...),
-			VerificationScript: sender.PublicKey().GetVerificationScript(),
-		}
 		bytes, err := p.Bytes()
 		require.NoError(t, err)
 		str := fmt.Sprintf(`"%s"`, base64.StdEncoding.EncodeToString(bytes))
@@ -1150,6 +1115,50 @@ func TestSubmitNotaryRequest(t *testing.T) {
 	})
 }
 
+// createValidNotaryRequest creates and signs P2PNotaryRequest payload which can
+// pass verification.
+func createValidNotaryRequest(chain *core.Blockchain, sender *keys.PrivateKey, nonce uint32) *payload.P2PNotaryRequest {
+	h := chain.BlockHeight()
+	mainTx := &transaction.Transaction{
+		Nonce:           nonce,
+		Attributes:      []transaction.Attribute{{Type: transaction.NotaryAssistedT, Value: &transaction.NotaryAssisted{NKeys: 1}}},
+		Script:          []byte{byte(opcode.RET)},
+		ValidUntilBlock: h + 100,
+		Signers:         []transaction.Signer{{Account: sender.GetScriptHash()}},
+		Scripts: []transaction.Witness{{
+			InvocationScript:   []byte{1, 4, 7},
+			VerificationScript: []byte{3, 6, 9},
+		}},
+	}
+	fallbackTx := &transaction.Transaction{
+		Script:          []byte{byte(opcode.RET)},
+		ValidUntilBlock: h + 100,
+		Attributes: []transaction.Attribute{
+			{Type: transaction.NotValidBeforeT, Value: &transaction.NotValidBefore{Height: h + 50}},
+			{Type: transaction.ConflictsT, Value: &transaction.Conflicts{Hash: mainTx.Hash()}},
+			{Type: transaction.NotaryAssistedT, Value: &transaction.NotaryAssisted{NKeys: 0}},
+		},
+		Signers: []transaction.Signer{{Account: chain.GetNotaryContractScriptHash()}, {Account: sender.GetScriptHash()}},
+		Scripts: []transaction.Witness{
+			{InvocationScript: append([]byte{byte(opcode.PUSHDATA1), 64}, make([]byte, 64)...), VerificationScript: []byte{}},
+		},
+		NetworkFee: 2_0000_0000,
+	}
+	fallbackTx.Scripts = append(fallbackTx.Scripts, transaction.Witness{
+		InvocationScript:   append([]byte{byte(opcode.PUSHDATA1), 64}, sender.SignHashable(uint32(testchain.Network()), fallbackTx)...),
+		VerificationScript: sender.PublicKey().GetVerificationScript(),
+	})
+	p := &payload.P2PNotaryRequest{
+		MainTransaction:     mainTx,
+		FallbackTransaction: fallbackTx,
+	}
+	p.Witness = transaction.Witness{
+		InvocationScript:   append([]byte{byte(opcode.PUSHDATA1), 64}, sender.SignHashable(uint32(testchain.Network()), p)...),
+		VerificationScript: sender.PublicKey().GetVerificationScript(),
+	}
+	return p
+}
+
 // testRPCProtocol runs a full set of tests using given callback to make actual
 // calls. Some tests change the chain state, thus we reinitialize the chain from
 // scratch here.

pkg/rpc/server/subscription.go

@@ -80,6 +80,21 @@ func (f *feed) Matches(r *response.Notification) bool {
 		filt := f.filter.(request.ExecutionFilter)
 		applog := r.Payload[0].(*state.AppExecResult)
 		return applog.VMState.String() == filt.State
+	case response.NotaryRequestEventID:
+		filt := f.filter.(request.TxFilter)
+		req := r.Payload[0].(*response.NotaryRequestEvent)
+		senderOk := filt.Sender == nil || req.NotaryRequest.FallbackTransaction.Signers[1].Account == *filt.Sender
+		signerOK := true
+		if filt.Signer != nil {
+			signerOK = false
+			for _, signer := range req.NotaryRequest.MainTransaction.Signers {
+				if signer.Account.Equals(*filt.Signer) {
+					signerOK = true
+					break
+				}
+			}
+		}
+		return senderOk && signerOK
 	}
 	return false
 }

pkg/rpc/server/subscription_test.go

@@ -86,10 +86,12 @@ func callUnsubscribe(t *testing.T, ws *websocket.Conn, msgs <-chan []byte, id st
 
 func TestSubscriptions(t *testing.T) {
 	var subIDs = make([]string, 0)
-	var subFeeds = []string{"block_added", "transaction_added", "notification_from_execution", "transaction_executed"}
+	var subFeeds = []string{"block_added", "transaction_added", "notification_from_execution", "transaction_executed", "notary_request_event"}
 
 	chain, rpcSrv, c, respMsgs, finishedFlag := initCleanServerAndWSClient(t)
 
+	go rpcSrv.coreServer.Start(make(chan error))
+	defer rpcSrv.coreServer.Shutdown()
 	defer chain.Close()
 	defer func() { _ = rpcSrv.Shutdown() }()
 
@@ -133,6 +135,17 @@ func TestSubscriptions(t *testing.T) {
 		require.Equal(t, response.BlockEventID, resp.Event)
 	}
 
+	// We should manually add NotaryRequest to test notification.
+	sender := testchain.PrivateKeyByID(0)
+	err := rpcSrv.coreServer.RelayP2PNotaryRequest(createValidNotaryRequest(chain, sender, 1))
+	require.NoError(t, err)
+	for {
+		resp := getNotification(t, respMsgs)
+		if resp.Event == response.NotaryRequestEventID {
+			break
+		}
+	}
+
 	for _, id := range subIDs {
 		callUnsubscribe(t, c, respMsgs, id)
 	}
@@ -277,6 +290,100 @@ func TestFilteredSubscriptions(t *testing.T) {
 	}
 }
 
+func TestFilteredNotaryRequestSubscriptions(t *testing.T) {
+	// We can't fit this into TestFilteredSubscriptions, because notary requests
+	// event doesn't depend on blocks events.
+	priv0 := testchain.PrivateKeyByID(0)
+	var goodSender = priv0.GetScriptHash()
+
+	var cases = map[string]struct {
+		params string
+		check  func(*testing.T, *response.Notification)
+	}{
+		"matching sender": {
+			params: `["notary_request_event", {"sender":"` + goodSender.StringLE() + `"}]`,
+			check: func(t *testing.T, resp *response.Notification) {
+				rmap := resp.Payload[0].(map[string]interface{})
+				require.Equal(t, response.NotaryRequestEventID, resp.Event)
+				require.Equal(t, "added", rmap["type"].(string))
+				req := rmap["notaryrequest"].(map[string]interface{})
+				fbTx := req["fallbacktx"].(map[string]interface{})
+				sender := fbTx["signers"].([]interface{})[1].(map[string]interface{})["account"].(string)
+				require.Equal(t, "0x"+goodSender.StringLE(), sender)
+			},
+		},
+		"matching signer": {
+			params: `["notary_request_event", {"signer":"` + goodSender.StringLE() + `"}]`,
+			check: func(t *testing.T, resp *response.Notification) {
+				rmap := resp.Payload[0].(map[string]interface{})
+				require.Equal(t, response.NotaryRequestEventID, resp.Event)
+				require.Equal(t, "added", rmap["type"].(string))
+				req := rmap["notaryrequest"].(map[string]interface{})
+				mainTx := req["maintx"].(map[string]interface{})
+				signers := mainTx["signers"].([]interface{})
+				signer0 := signers[0].(map[string]interface{})
+				signer0acc := signer0["account"].(string)
+				require.Equal(t, "0x"+goodSender.StringLE(), signer0acc)
+			},
+		},
+		"matching sender and signer": {
+			params: `["notary_request_event", {"sender":"` + goodSender.StringLE() + `", "signer":"` + goodSender.StringLE() + `"}]`,
+			check: func(t *testing.T, resp *response.Notification) {
+				rmap := resp.Payload[0].(map[string]interface{})
+				require.Equal(t, response.NotaryRequestEventID, resp.Event)
+				require.Equal(t, "added", rmap["type"].(string))
+				req := rmap["notaryrequest"].(map[string]interface{})
+				mainTx := req["maintx"].(map[string]interface{})
+				fbTx := req["fallbacktx"].(map[string]interface{})
+				sender := fbTx["signers"].([]interface{})[1].(map[string]interface{})["account"].(string)
+				require.Equal(t, "0x"+goodSender.StringLE(), sender)
+				signers := mainTx["signers"].([]interface{})
+				signer0 := signers[0].(map[string]interface{})
+				signer0acc := signer0["account"].(string)
+				require.Equal(t, "0x"+goodSender.StringLE(), signer0acc)
+			},
+		},
+	}
+
+	chain, rpcSrv, c, respMsgs, finishedFlag := initCleanServerAndWSClient(t)
+	go rpcSrv.coreServer.Start(make(chan error, 1))
+
+	defer chain.Close()
+	defer func() { _ = rpcSrv.Shutdown() }()
+
+	// blocks are needed to make GAS deposit for priv0
+	blocks := getTestBlocks(t)
+	for _, b := range blocks {
+		require.NoError(t, chain.AddBlock(b))
+	}
+
+	var nonce uint32 = 100
+	for name, this := range cases {
+		t.Run(name, func(t *testing.T) {
+			subID := callSubscribe(t, c, respMsgs, this.params)
+
+			err := rpcSrv.coreServer.RelayP2PNotaryRequest(createValidNotaryRequest(chain, priv0, nonce))
+			require.NoError(t, err)
+			nonce++
+
+			var resp = new(response.Notification)
+			select {
+			case body := <-respMsgs:
+				require.NoError(t, json.Unmarshal(body, resp))
+			case <-time.After(time.Second):
+				t.Fatal("timeout waiting for event")
+			}
+
+			require.Equal(t, response.NotaryRequestEventID, resp.Event)
+			this.check(t, resp)
+
+			callUnsubscribe(t, c, respMsgs, subID)
+		})
+	}
+	finishedFlag.CAS(false, true)
+	c.Close()
+}
+
 func TestFilteredBlockSubscriptions(t *testing.T) {
 	// We can't fit this into TestFilteredSubscriptions, because it uses
 	// blocks as EOF events to wait for.