[FAB-8944] Refresh membership only on config update

Change-Id: Ia919caf72c247ed0df25a658c4575befb119bf09
Signed-off-by: Divyank Katira <Divyank.Katira@securekey.com>

Author: d1vyank

pkg/common/providers/fab/channel.go

@@ -30,6 +30,7 @@ type ChannelConfig interface {
 // ChannelCfg contains channel configuration
 type ChannelCfg interface {
 	ID() string
+	BlockNumber() uint64
 	MSPs() []*mspCfg.MSPConfig
 	AnchorPeers() []*OrgAnchorPeer
 	Orderers() []string

pkg/fab/channel/ledger.go

@@ -209,8 +209,7 @@ func createChaincodeQueryResponse(tpr *fab.TransactionProposalResponse) (*pb.Cha
 
 // QueryConfigBlock returns the current configuration block for the specified channel. If the
 // peer doesn't belong to the channel, return error
-func (c *Ledger) QueryConfigBlock(reqCtx reqContext.Context, targets []fab.ProposalProcessor, verifier ResponseVerifier) (*common.ConfigEnvelope, error) {
-
+func (c *Ledger) QueryConfigBlock(reqCtx reqContext.Context, targets []fab.ProposalProcessor, verifier ResponseVerifier) (*common.Block, error) {
 	if len(targets) == 0 {
 		return nil, errors.New("target(s) required")
 	}
@@ -226,10 +225,7 @@ func (c *Ledger) QueryConfigBlock(reqCtx reqContext.Context, targets []fab.Propo
 		return nil, matchErr
 	}
 
-	block, _ := createCommonBlock(tprs[0])
-
-	return createConfigEnvelope(block.Data.Data[0])
-
+	return createCommonBlock(tprs[0])
 }
 
 func collectProposalResponses(tprs []*fab.TransactionProposalResponse) [][]byte {
@@ -286,28 +282,3 @@ func createChaincodeInvokeRequest() fab.ChaincodeInvokeRequest {
 	}
 	return cir
 }
-
-func createConfigEnvelope(data []byte) (*common.ConfigEnvelope, error) {
-
-	envelope := &common.Envelope{}
-	if err := proto.Unmarshal(data, envelope); err != nil {
-		return nil, errors.Wrap(err, "unmarshal envelope from config block failed")
-	}
-	payload := &common.Payload{}
-	if err := proto.Unmarshal(envelope.Payload, payload); err != nil {
-		return nil, errors.Wrap(err, "unmarshal payload from envelope failed")
-	}
-	channelHeader := &common.ChannelHeader{}
-	if err := proto.Unmarshal(payload.Header.ChannelHeader, channelHeader); err != nil {
-		return nil, errors.Wrap(err, "unmarshal payload from envelope failed")
-	}
-	if common.HeaderType(channelHeader.Type) != common.HeaderType_CONFIG {
-		return nil, errors.New("block must be of type 'CONFIG'")
-	}
-	configEnvelope := &common.ConfigEnvelope{}
-	if err := proto.Unmarshal(payload.Data, configEnvelope); err != nil {
-		return nil, errors.Wrap(err, "unmarshal config envelope failed")
-	}
-
-	return configEnvelope, nil
-}

pkg/fab/channel/membership/reference.go

@@ -19,6 +19,9 @@ type Ref struct {
 	*lazyref.Reference
 	chConfigRef *lazyref.Reference
 	context     Context
+	// Note: the following variables are only accessed from Ref.initializer which is synchronized
+	configBlockNumber uint64
+	mem               fab.ChannelMembership
 }
 
 // NewRef returns a new membership reference
@@ -64,7 +67,7 @@ func (ref *Ref) get() (fab.ChannelMembership, error) {
 
 func (ref *Ref) initializer() lazyref.Initializer {
 	return func() (interface{}, error) {
-		logger.Debugf("Creating membership...")
+		logger.Debugf("Initializing membership reference...")
 
 		channelCfg, err := ref.chConfigRef.Get()
 		if err != nil {
@@ -75,12 +78,17 @@ func (ref *Ref) initializer() lazyref.Initializer {
 			return nil, errors.New("chConfigRef.Get() returned unexpected value ")
 		}
 
-		//TODO: create new membership only if config block number has changed
-		membership, err := New(ref.context, cfg)
-		if err != nil {
-			return nil, err
+		logger.Debugf("Got config block with number %d have %d", cfg.BlockNumber(), ref.configBlockNumber)
+
+		// Membership is refreshed only if we have a newer config block
+		if ref.mem == nil || cfg.BlockNumber() > ref.configBlockNumber {
+			logger.Debugf("Creating membership...")
+			ref.mem, err = New(ref.context, cfg)
+			if err != nil {
+				return nil, err
+			}
 		}
 
-		return membership, nil
+		return ref.mem, nil
 	}
 }

pkg/fab/chconfig/chconfig.go

@@ -63,6 +63,7 @@ type ChannelConfig struct {
 // ChannelCfg contains channel configuration
 type ChannelCfg struct {
 	id          string
+	blockNumber uint64
 	msps        []*mb.MSPConfig
 	anchorPeers []*fab.OrgAnchorPeer
 	orderers    []string
@@ -80,6 +81,11 @@ func (cfg *ChannelCfg) ID() string {
 	return cfg.id
 }
 
+// BlockNumber returns the channel config block number
+func (cfg *ChannelCfg) BlockNumber() uint64 {
+	return cfg.blockNumber
+}
+
 // MSPs returns msps
 func (cfg *ChannelCfg) MSPs() []*mb.MSPConfig {
 	return cfg.msps
@@ -157,22 +163,22 @@ func (c *ChannelConfig) queryPeers(reqCtx reqContext.Context) (*ChannelCfg, erro
 		targets = peersToTxnProcessors(c.opts.Targets)
 	}
 
-	configEnvelope, err := l.QueryConfigBlock(reqCtx, targets, &channel.TransactionProposalResponseVerifier{MinResponses: minResponses})
+	block, err := l.QueryConfigBlock(reqCtx, targets, &channel.TransactionProposalResponseVerifier{MinResponses: minResponses})
 	if err != nil {
 		return nil, errors.WithMessage(err, "QueryBlockConfig failed")
 	}
 
-	return extractConfig(c.channelID, configEnvelope)
+	return extractConfig(c.channelID, block)
 }
 
 func (c *ChannelConfig) queryOrderer(reqCtx reqContext.Context) (*ChannelCfg, error) {
 
-	configEnvelope, err := resource.LastConfigFromOrderer(reqCtx, c.channelID, c.opts.Orderer)
+	block, err := resource.LastConfigFromOrderer(reqCtx, c.channelID, c.opts.Orderer)
 	if err != nil {
 		return nil, errors.WithMessage(err, "LastConfigFromOrderer failed")
 	}
 
-	return extractConfig(c.channelID, configEnvelope)
+	return extractConfig(c.channelID, block)
 }
 
 func (c *ChannelConfig) getLimitOpts(ctx context.Client) (int, int) {
@@ -251,7 +257,15 @@ func prepareOpts(options ...Option) (Opts, error) {
 	return opts, nil
 }
 
-func extractConfig(channelID string, configEnvelope *common.ConfigEnvelope) (*ChannelCfg, error) {
+func extractConfig(channelID string, block *common.Block) (*ChannelCfg, error) {
+	if block.Header == nil {
+		return nil, errors.New("expected header in block")
+	}
+
+	configEnvelope, err := resource.CreateConfigEnvelope(block.Data.Data[0])
+	if err != nil {
+		return nil, err
+	}
 
 	group := configEnvelope.Config.ChannelGroup
 
@@ -261,13 +275,14 @@ func extractConfig(channelID string, configEnvelope *common.ConfigEnvelope) (*Ch
 
 	config := &ChannelCfg{
 		id:          channelID,
+		blockNumber: block.Header.Number,
 		msps:        []*mb.MSPConfig{},
 		anchorPeers: []*fab.OrgAnchorPeer{},
 		orderers:    []string{},
 		versions:    versions,
 	}
 
-	err := loadConfig(config, config.versions.Channel, group, "base", "", true)
+	err = loadConfig(config, config.versions.Channel, group, "base", "", true)
 	if err != nil {
 		return nil, errors.WithMessage(err, "load config items from config group failed")
 	}

pkg/fab/mocks/mockchconfig.go

@@ -17,6 +17,7 @@ import (
 // MockChannelCfg contains mock channel configuration
 type MockChannelCfg struct {
 	MockID          string
+	MockBlockNumber uint64
 	MockMSPs        []*msp.MSPConfig
 	MockAnchorPeers []*fab.OrgAnchorPeer
 	MockOrderers    []string
@@ -34,6 +35,11 @@ func (cfg *MockChannelCfg) ID() string {
 	return cfg.MockID
 }
 
+// BlockNumber returns block number
+func (cfg *MockChannelCfg) BlockNumber() uint64 {
+	return cfg.MockBlockNumber
+}
+
 // MSPs returns msps
 func (cfg *MockChannelCfg) MSPs() []*msp.MSPConfig {
 	return cfg.MockMSPs

pkg/fab/resource/resource.go

@@ -116,7 +116,7 @@ func GenesisBlockFromOrderer(reqCtx reqContext.Context, channelName string, orde
 
 // LastConfigFromOrderer fetches the current configuration block for the specified channel
 // from the given orderer
-func LastConfigFromOrderer(reqCtx reqContext.Context, channelName string, orderer fab.Orderer) (*common.ConfigEnvelope, error) {
+func LastConfigFromOrderer(reqCtx reqContext.Context, channelName string, orderer fab.Orderer) (*common.Block, error) {
 	logger.Debugf("channelConfig - start for channel %s", channelName)
 
 	// Get the newest block
@@ -144,7 +144,7 @@ func LastConfigFromOrderer(reqCtx reqContext.Context, channelName string, ordere
 		return nil, errors.New("apiconfig block must contain one transaction")
 	}
 
-	return CreateConfigEnvelope(block.Data.Data[0])
+	return block, nil
 }
 
 // JoinChannel sends a join channel proposal to the target peer.