[FAB-2703] (PA) Expose committed configEnvelope

The config manager does not currently store the raw config envelope
which generated the current config.  For constructions which require
access to the raw keys, this is problematic, so this CR stores, and adds
a method to access this config envelop.

Change-Id: Icf41cbef118f920f346325fcb11b710dbdeccf97
Signed-off-by: Jason Yellick <jyellick@us.ibm.com>
Signed-off-by: Kostas Christidis <kostas@christidis.io>

common/configtx/api/api.go

@@ -41,6 +41,9 @@ type Manager interface {
 	// ChainID retrieves the chain ID associated with this manager
 	ChainID() string
 
+	// ConfigEnvelope returns the current config envelope
+	ConfigEnvelope() *cb.ConfigEnvelope
+
 	// Sequence returns the current sequence number of the config
 	Sequence() uint64
 }

common/configtx/manager.go

@@ -43,6 +43,7 @@ type configSet struct {
 	channelID string
 	sequence  uint64
 	configMap map[string]comparable
+	configEnv *cb.ConfigEnvelope
 }
 
 type configManager struct {
@@ -113,6 +114,7 @@ func NewManagerImpl(envConfig *cb.Envelope, initializer api.Initializer, callOnU
 			sequence:  configEnv.Config.Sequence,
 			configMap: configMap,
 			channelID: header.ChannelId,
+			configEnv: configEnv,
 		},
 		callOnUpdate: callOnUpdate,
 	}
@@ -142,12 +144,12 @@ func (cm *configManager) ProposeConfigUpdate(configtx *cb.Envelope) (*cb.ConfigE
 func (cm *configManager) proposeConfigUpdate(configtx *cb.Envelope) (*cb.ConfigEnvelope, error) {
 	configUpdateEnv, err := envelopeToConfigUpdate(configtx)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("Error converting envelope to config update: %s", err)
 	}
 
 	configMap, err := cm.authorizeUpdate(configUpdateEnv)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("Error authorizing update: %s", err)
 	}
 
 	channelGroup, err := configMapToConfig(configMap)
@@ -157,7 +159,7 @@ func (cm *configManager) proposeConfigUpdate(configtx *cb.Envelope) (*cb.ConfigE
 
 	result, err := cm.processConfig(channelGroup)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("Error processing updated config: %s", err)
 	}
 
 	result.rollback()
@@ -231,14 +233,16 @@ func (cm *configManager) Apply(configEnv *cb.ConfigEnvelope) error {
 	}
 
 	result.commit()
-	cm.commitCallbacks()
 
 	cm.current = &configSet{
 		configMap: configMap,
 		channelID: cm.current.channelID,
 		sequence:  configEnv.Config.Sequence,
+		configEnv: configEnv,
 	}
 
+	cm.commitCallbacks()
+
 	return nil
 }
 
@@ -251,3 +255,8 @@ func (cm *configManager) ChainID() string {
 func (cm *configManager) Sequence() uint64 {
 	return cm.current.sequence
 }
+
+// ConfigEnvelope returns the current config envelope
+func (cm *configManager) ConfigEnvelope() *cb.ConfigEnvelope {
+	return cm.current.configEnv
+}

common/mocks/configtx/configtx.go

@@ -179,11 +179,14 @@ type Manager struct {
 
 	// ProposeConfigUpdateVal is returns as the value for ProposeConfigUpdate
 	ProposeConfigUpdateVal *cb.ConfigEnvelope
+
+	// ConfigEnvelopeVal is returned as the value for ConfigEnvelope()
+	ConfigEnvelopeVal *cb.ConfigEnvelope
 }
 
-// ConfigEnvelope is currently unimplemented
+// ConfigEnvelope returns the ConfigEnvelopeVal
 func (cm *Manager) ConfigEnvelope() *cb.ConfigEnvelope {
-	panic("Unimplemented")
+	return cm.ConfigEnvelopeVal
 }
 
 // ConsensusType returns the ConsensusTypeVal