[FAB-1710] Add orderer addresses to chain config

https://jira.hyperledger.org/browse/FAB-1710

This adds the proto support for listing the orderer addresses as
a configuration item of type Chain.  It also implements the chainconfig
Handler for this type to expose it to consumers.

This changeset does not actually set or utilize the type, simply adds
it.

Change-Id: I225d859b4b31df8bde9afec72e1f9d22c7cfe174
Signed-off-by: Jason Yellick <[email protected]>

Author: Jason Yellick

common/chainconfig/chainconfig.go

@@ -33,6 +33,9 @@ const (
 
 	// BlockDataHashingStructureKey is the cb.ConfigurationItem type key name for the BlockDataHashingStructure message
 	BlockDataHashingStructureKey = "BlockDataHashingStructure"
+
+	// OrdererAddressesKey is the cb.ConfigurationItem type key name for the OrdererAddresses message
+	OrdererAddressesKey = "OrdererAddresses"
 )
 
 // Hashing algorithm types
@@ -55,11 +58,15 @@ type Descriptor interface {
 	// BlockDataHashingStructureWidth returns the width to use when constructing the
 	// Merkle tree to compute the BlockData hash
 	BlockDatahashingStructureWidth() int
+
+	// OrdererAddresses returns the list of valid orderer addresses to connect to to invoke Broadcast/Deliver
+	OrdererAddresses() []string
 }
 
 type chainConfig struct {
 	hashingAlgorithm               func(input []byte) []byte
 	blockDataHashingStructureWidth uint32
+	ordererAddresses               []string
 }
 
 // DescriptorImpl is an implementation of Manager and configtx.ConfigHandler
@@ -86,6 +93,11 @@ func (pm *DescriptorImpl) BlockDataHashingStructureWidth() uint32 {
 	return pm.config.blockDataHashingStructureWidth
 }
 
+// OrdererAddresses returns the list of valid orderer addresses to connect to to invoke Broadcast/Deliver
+func (pm *DescriptorImpl) OrdererAddresses() []string {
+	return pm.config.ordererAddresses
+}
+
 // BeginConfig is used to start a new configuration proposal
 func (pm *DescriptorImpl) BeginConfig() {
 	if pm.pendingConfig != nil {
@@ -137,6 +149,12 @@ func (pm *DescriptorImpl) ProposeConfig(configItem *cb.ConfigurationItem) error
 		}
 
 		pm.pendingConfig.blockDataHashingStructureWidth = blockDataHashingStructure.Width
+	case OrdererAddressesKey:
+		ordererAddresses := &cb.OrdererAddresses{}
+		if err := proto.Unmarshal(configItem.Value, ordererAddresses); err != nil {
+			return fmt.Errorf("Unmarshaling error for HashingAlgorithm: %s", err)
+		}
+		pm.pendingConfig.ordererAddresses = ordererAddresses.Addresses
 	default:
 		logger.Warningf("Uknown Chain configuration item with key %s", configItem.Key)
 	}

common/chainconfig/chainconfig_test.go

@@ -17,6 +17,7 @@ limitations under the License.
 package chainconfig
 
 import (
+	"reflect"
 	"testing"
 
 	cb "github.com/hyperledger/fabric/protos/common"
@@ -145,3 +146,35 @@ func TestBlockDataHashingStructure(t *testing.T) {
 		t.Fatalf("Unexpected width, got %d expected %d", newWidth, expectedWidth)
 	}
 }
+
+func TestOrdererAddresses(t *testing.T) {
+	expectedResult := []string{"foo", "bar:1234"}
+	invalidMessage := &cb.ConfigurationItem{
+		Type:  cb.ConfigurationItem_Chain,
+		Key:   BlockDataHashingStructureKey,
+		Value: []byte("Garbage Data"),
+	}
+	validMessage := &cb.ConfigurationItem{
+		Type:  cb.ConfigurationItem_Chain,
+		Key:   OrdererAddressesKey,
+		Value: utils.MarshalOrPanic(&cb.OrdererAddresses{Addresses: expectedResult}),
+	}
+	m := NewDescriptorImpl()
+	m.BeginConfig()
+
+	err := m.ProposeConfig(invalidMessage)
+	if err == nil {
+		t.Fatalf("Should have failed on invalid message")
+	}
+
+	err = m.ProposeConfig(validMessage)
+	if err != nil {
+		t.Fatalf("Error applying valid config: %s", err)
+	}
+
+	m.CommitConfig()
+
+	if newAddrs := m.OrdererAddresses(); !reflect.DeepEqual(newAddrs, expectedResult) {
+		t.Fatalf("Unexpected width, got %s expected %s", newAddrs, expectedResult)
+	}
+}

protos/common/common.pb.go

@@ -132,3 +132,9 @@ message BlockDataHashingStructure {
     // in order to replicate flat hashing, set this width to MAX_UINT32
     uint32 width  = 1;
 }
+
+// OrdererAddresses is encoded into the configuration transaction as a configuration item of type Chain
+// with a Key of "OrdererAddresses" and a Value of OrdererAddresses as marshaled protobuf bytes
+message OrdererAddresses {
+    repeated string addresses = 1;
+}