Use local peer ledger height from ledger instead of discovery in Gate…

…way (#4048)

Discovery ledger heights can be slightly behind the actual peer ledger height. Ensure the most up-to-date information is used for the local peer by querying the ledger height directly. This avoids the possibility of a remote peer with a lower ledger height being selected as an endorser.

Signed-off-by: Mark S. Lewis <Mark.S.Lewis@outlook.com>

internal/pkg/gateway/endorse_test.go

@@ -55,6 +55,30 @@ func TestEndorse(t *testing.T) {
 			},
 			expectedEndorsers: []string{"localhost:7051", "peer2:9051"},
 		},
+		{
+			name: "use highest block height local org peer",
+			plan: endorsementPlan{
+				"g1": {{endorser: peer1Mock, height: 5}, {endorser: localhostMock, height: 4}}, // msp1
+			},
+			members: []networkMember{
+				{string(localhostMock.pkiid), localhostMock.address, localhostMock.mspid, 4},
+				{string(peer1Mock.pkiid), peer1Mock.address, peer1Mock.mspid, 5},
+			},
+			localLedgerHeight: 4,
+			expectedEndorsers: []string{peer1Mock.address},
+		},
+		{
+			name: "use local host ledger height",
+			plan: endorsementPlan{
+				"g1": {{endorser: peer1Mock, height: 5}, {endorser: localhostMock, height: 4}}, // msp1
+			},
+			members: []networkMember{
+				{string(localhostMock.pkiid), localhostMock.address, localhostMock.mspid, 4},
+				{string(peer1Mock.pkiid), peer1Mock.address, peer1Mock.mspid, 5},
+			},
+			localLedgerHeight: 6,
+			expectedEndorsers: []string{localhostMock.address},
+		},
 		{
 			name:              "endorse with specified orgs, despite block height",
 			endorsingOrgs:     []string{"msp1", "msp3"},

internal/pkg/gateway/evaluate_test.go

@@ -341,6 +341,15 @@ func TestEvaluate(t *testing.T) {
 			errCode:   codes.DeadlineExceeded,
 			errString: "evaluate timeout expired",
 		},
+		{
+			name: "uses local host ledger height",
+			members: []networkMember{
+				{"id2", "peer1:8051", "msp1", 6},
+				{"id1", "localhost:7051", "msp1", 5},
+			},
+			localLedgerHeight: 7,
+			expectedEndorsers: []string{"localhost:7051"},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {

internal/pkg/gateway/gateway.go

@@ -115,6 +115,7 @@ func newServer(localEndorser peerproto.EndorserClient,
 			remoteEndorsers:    map[string]*endorser{},
 			channelInitialized: map[string]bool{},
 			systemChaincodes:   systemChaincodes,
+			localProvider:      ledgerProvider,
 		},
 		commitFinder:   finder,
 		policy:         policy,

internal/pkg/gateway/registry.go

@@ -23,6 +23,7 @@ import (
 	gossipapi "github.com/hyperledger/fabric/gossip/api"
 	gossipcommon "github.com/hyperledger/fabric/gossip/common"
 	gossipdiscovery "github.com/hyperledger/fabric/gossip/discovery"
+	"github.com/hyperledger/fabric/internal/pkg/gateway/ledger"
 	"github.com/pkg/errors"
 )
 
@@ -44,6 +45,7 @@ type registry struct {
 	configLock         sync.RWMutex
 	channelOrderers    sync.Map // channel (string) -> orderer addresses (endpointConfig)
 	systemChaincodes   scc.BuiltinSCCs
+	localProvider      ledger.Provider
 }
 
 type endorserState struct {
@@ -200,13 +202,42 @@ func (reg *registry) endorsersByOrg(channel string, chaincode string) map[string
 }
 
 func (reg *registry) channelMembers(channel string) gossipdiscovery.Members {
-	return reg.discovery.PeersOfChannel(gossipcommon.ChannelID(channel))
+	members := reg.discovery.PeersOfChannel(gossipcommon.ChannelID(channel))
+
+	// Ensure local endorser ledger height is up-to-date
+	for _, member := range members {
+		if reg.isLocalEndorserID(member.PKIid) {
+			if ledgerHeight, ok := reg.localLedgerHeight(channel); ok {
+				member.Properties.LedgerHeight = ledgerHeight
+			}
+
+			break
+		}
+	}
+
+	return members
 }
 
 func (reg *registry) isLocalEndorserID(pkiID gossipcommon.PKIidType) bool {
 	return !pkiID.IsNotSameFilter(reg.localEndorser.pkiid)
 }
 
+func (reg *registry) localLedgerHeight(channel string) (height uint64, ok bool) {
+	ledger, err := reg.localProvider.Ledger(channel)
+	if err != nil {
+		reg.logger.Warnw("local endorser is not a member of channel", "channel", channel, "err", err)
+		return 0, false
+	}
+
+	info, err := ledger.GetBlockchainInfo()
+	if err != nil {
+		logger.Errorw("failed to get local ledger info", "err", err)
+		return 0, false
+	}
+
+	return info.GetHeight(), true
+}
+
 // evaluator returns a plan representing a single endorsement, preferably from local org, if available
 // targetOrgs specifies the orgs that are allowed receive the request, due to private data restrictions
 func (reg *registry) evaluator(channel string, chaincode string, targetOrgs []string) (*plan, error) {