[FAB-4619] enable specifying orderer kafka version

Kafka version can now be set in orderer.yaml, eg:

Kakfa:
  Version: 0.10.0.0

Default value is '0.9.0.1'.

Change-Id: Ieb69b003b400bff9c7918743e99ce76c4ad4363c
Signed-off-by: Luis Sanchez <sanchezl@us.ibm.com>

common/viperutil/config_test.go

@@ -25,6 +25,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/Shopify/sarama"
 	"github.com/hyperledger/fabric/orderer/mocks/util"
 	"github.com/spf13/viper"
 )
@@ -70,6 +71,63 @@ func TestEnvSlice(t *testing.T) {
 	}
 }
 
+func TestKafkaVersionDecode(t *testing.T) {
+
+	type testKafkaVersion struct {
+		Inner struct {
+			Version sarama.KafkaVersion
+		}
+	}
+
+	config := viper.New()
+	config.SetConfigType("yaml")
+
+	testCases := []struct {
+		data        string
+		expected    sarama.KafkaVersion
+		errExpected bool
+	}{
+		{"0.8.2.0", sarama.V0_8_2_0, false},
+		{"0.8.2.1", sarama.V0_8_2_1, false},
+		{"0.8.2.2", sarama.V0_8_2_2, false},
+		{"0.9.0.0", sarama.V0_9_0_0, false},
+		{"0.9.0.1", sarama.V0_9_0_1, false},
+		{"0.10.0.0", sarama.V0_10_0_0, false},
+		{"0.10.0.1", sarama.V0_10_0_1, false},
+		{"0.10.1.0", sarama.V0_10_1_0, false},
+		{"Unsupported", sarama.KafkaVersion{}, true},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.data, func(t *testing.T) {
+
+			data := fmt.Sprintf("---\nInner:\n    Version: %s", tc.data)
+			err := config.ReadConfig(bytes.NewReader([]byte(data)))
+			if err != nil {
+				t.Fatalf("Error reading config: %s", err)
+			}
+
+			var uconf testKafkaVersion
+			err = EnhancedExactUnmarshal(config, &uconf)
+
+			if tc.errExpected {
+				if err == nil {
+					t.Fatalf("Should have failed to unmarshal")
+				}
+			} else {
+				if err != nil {
+					t.Fatalf("Failed to unmarshal with: %s", err)
+				}
+				if uconf.Inner.Version != tc.expected {
+					t.Fatalf("Did not get back the right kafka version, expected: %v got %v", tc.expected, uconf.Inner.Version)
+				}
+			}
+
+		})
+	}
+
+}
+
 type testByteSize struct {
 	Inner struct {
 		ByteSize uint32

common/viperutil/config_util.go

@@ -29,6 +29,7 @@ import (
 	"encoding/json"
 	"encoding/pem"
 
+	"github.com/Shopify/sarama"
 	"github.com/hyperledger/fabric/common/flogging"
 	"github.com/mitchellh/mapstructure"
 	"github.com/spf13/viper"
@@ -254,6 +255,34 @@ func pemBlocksFromFileDecodeHook() mapstructure.DecodeHookFunc {
 	}
 }
 
+func kafkaVersionDecodeHook() mapstructure.DecodeHookFunc {
+	return func(f reflect.Type, t reflect.Type, data interface{}) (interface{}, error) {
+		if f.Kind() != reflect.String || t != reflect.TypeOf(sarama.KafkaVersion{}) {
+			return data, nil
+		}
+		switch data {
+		case "0.8.2.0":
+			return sarama.V0_8_2_0, nil
+		case "0.8.2.1":
+			return sarama.V0_8_2_1, nil
+		case "0.8.2.2":
+			return sarama.V0_8_2_2, nil
+		case "0.9.0.0":
+			return sarama.V0_9_0_0, nil
+		case "0.9.0.1":
+			return sarama.V0_9_0_1, nil
+		case "0.10.0.0":
+			return sarama.V0_10_0_0, nil
+		case "0.10.0.1":
+			return sarama.V0_10_0_1, nil
+		case "0.10.1.0":
+			return sarama.V0_10_1_0, nil
+		default:
+			return nil, fmt.Errorf("Unsupported Kafka version: '%s'", data)
+		}
+	}
+}
+
 // EnhancedExactUnmarshal is intended to unmarshal a config file into a structure
 // producing error when extraneous variables are introduced and supporting
 // the time.Duration type
@@ -274,6 +303,7 @@ func EnhancedExactUnmarshal(v *viper.Viper, output interface{}) error {
 			byteSizeDecodeHook(),
 			stringFromFileDecodeHook(),
 			pemBlocksFromFileDecodeHook(),
+			kafkaVersionDecodeHook(),
 		),
 	}
 

docs/source/kafka.rst

@@ -185,22 +185,15 @@ Supported Kafka versions for v1 are ``0.9`` and ``0.10``. (Fabric uses the
 version of it that supports Kafka 0.9 and 0.10.)
 
 Out of the box the Kafka version defaults to ``0.9.0.1``. If you wish to use a
-different supported version, you will have to edit the source code (modify the
-``Version`` field of the ``defaults`` struct in
-``orderer/localconfig/config.go``) and rebuild the ``orderer`` binary. For
-example, if you wish to run the ordering service in a Kafka cluster running
-0.10.0.1, you would edit the file like so:
-
-::
-
-    ...
-    Verbose: false,
-    Version: sarama.V0_10_0_1,
-    TLS: TLS{
-    ...
-
-And then rebuild the binary. (This process will be improved with
-`FAB-4619 <https://jira.hyperledger.org/browse/FAB-4619>`_.)
+different supported version, specify a supported version using the
+``Kafka.Version`` key in ``orderer.yaml``.
+
+The current supported Kafka versions are:
+
+* ``Version: 0.9.0.1``
+* ``Version: 0.10.0.0``
+* ``Version: 0.10.0.1``
+* ``Version: 0.10.1.0``
 
 Debugging
 ---------

examples/cluster/config/orderer.yaml

@@ -67,7 +67,7 @@ General:
 
     # LocalMSPID is the identity to register the local MSP material with the MSP
     # manager. IMPORTANT: The local MSP ID of an orderer needs to match the MSP
-    # ID of one of the organizations defined in the orderer system channel's 
+    # ID of one of the organizations defined in the orderer system channel's
     # /Channel/Orderer configuration. The sample organization defined in the
     # sample configuration provided has an MSP ID of "DEFAULT".
     LocalMSPID: OrdererMSP
@@ -221,3 +221,6 @@ Kafka:
         # following "File" key and specify the file name from which to load the
         # value of RootCAs.
         #File: path/to/RootCAs
+
+    # Kafka version of the Kafka cluster brokers (defaults to 0.9.0.1)
+    Version:

orderer/localconfig/config.go

@@ -340,10 +340,11 @@ func (c *TopLevel) completeInitialization(configDir string) {
 			logger.Infof("Kafka.Retry.Consumer.RetryBackoff unset, setting to %v", defaults.Kafka.Retry.Consumer.RetryBackoff)
 			c.Kafka.Retry.Consumer.RetryBackoff = defaults.Kafka.Retry.Consumer.RetryBackoff
 
-		default:
-			// A bit hacky, but its type makes it impossible to test for a nil value.
-			// This may be overwritten by the Kafka orderer upon instantiation.
+		case c.Kafka.Version == sarama.KafkaVersion{}:
+			logger.Infof("Kafka.Version unset, setting to %v", defaults.Kafka.Version)
 			c.Kafka.Version = defaults.Kafka.Version
+
+		default:
 			return
 		}
 	}

sampleconfig/orderer.yaml

@@ -67,7 +67,7 @@ General:
 
     # LocalMSPID is the identity to register the local MSP material with the MSP
     # manager. IMPORTANT: The local MSP ID of an orderer needs to match the MSP
-    # ID of one of the organizations defined in the orderer system channel's 
+    # ID of one of the organizations defined in the orderer system channel's
     # /Channel/Orderer configuration. The sample organization defined in the
     # sample configuration provided has an MSP ID of "DEFAULT".
     LocalMSPID: DEFAULT
@@ -221,3 +221,6 @@ Kafka:
         # following "File" key and specify the file name from which to load the
         # value of RootCAs.
         #File: path/to/RootCAs
+
+    # Kafka version of the Kafka cluster brokers (defaults to 0.9.0.1)
+    Version: