Add support for decoding versioned responses

This will be needed to properly parse kafka's 0.10.0 messages where the version
does not just affect the request format but also the response.

api_versions_request.go

@@ -7,7 +7,7 @@ func (r *ApiVersionsRequest) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *ApiVersionsRequest) decode(pd packetDecoder) (err error) {
+func (r *ApiVersionsRequest) decode(pd packetDecoder, version int16) (err error) {
 	return nil
 }
 

api_versions_response.go

@@ -49,7 +49,7 @@ func (r *ApiVersionsResponse) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *ApiVersionsResponse) decode(pd packetDecoder) error {
+func (r *ApiVersionsResponse) decode(pd packetDecoder, version int16) error {
 	if kerr, err := pd.getInt16(); err != nil {
 		return err
 	} else {
@@ -72,3 +72,11 @@ func (r *ApiVersionsResponse) decode(pd packetDecoder) error {
 
 	return nil
 }
+
+func (r *ApiVersionsResponse) key() int16 {
+	return 18
+}
+
+func (r *ApiVersionsResponse) version() int16 {
+	return 0
+}

api_versions_response_test.go

@@ -16,7 +16,7 @@ func TestApiVersionsResponse(t *testing.T) {
 	var response *ApiVersionsResponse
 
 	response = new(ApiVersionsResponse)
-	testDecodable(t, "no error", response, apiVersionResponse)
+	testVersionDecodable(t, "no error", response, apiVersionResponse, 0)
 	if response.Err != ErrNoError {
 		t.Error("Decoding error failed: no error expected but found", response.Err)
 	}

broker.go

@@ -317,7 +317,7 @@ func (b *Broker) DescribeGroups(request *DescribeGroupsRequest) (*DescribeGroups
 	return response, nil
 }
 
-func (b *Broker) send(rb requestBody, promiseResponse bool) (*responsePromise, error) {
+func (b *Broker) send(rb protocolBody, promiseResponse bool) (*responsePromise, error) {
 	b.lock.Lock()
 	defer b.lock.Unlock()
 
@@ -355,7 +355,7 @@ func (b *Broker) send(rb requestBody, promiseResponse bool) (*responsePromise, e
 	return &promise, nil
 }
 
-func (b *Broker) sendAndReceive(req requestBody, res decoder) error {
+func (b *Broker) sendAndReceive(req protocolBody, res versionedDecoder) error {
 	promise, err := b.send(req, res != nil)
 
 	if err != nil {
@@ -368,7 +368,7 @@ func (b *Broker) sendAndReceive(req requestBody, res decoder) error {
 
 	select {
 	case buf := <-promise.packets:
-		return decode(buf, res)
+		return versionedDecode(buf, res, req.version())
 	case err = <-promise.errors:
 		return err
 	}

consumer_metadata_request.go

@@ -8,7 +8,7 @@ func (r *ConsumerMetadataRequest) encode(pe packetEncoder) error {
 	return pe.putString(r.ConsumerGroup)
 }
 
-func (r *ConsumerMetadataRequest) decode(pd packetDecoder) (err error) {
+func (r *ConsumerMetadataRequest) decode(pd packetDecoder, version int16) (err error) {
 	r.ConsumerGroup, err = pd.getString()
 	return err
 }

consumer_metadata_response.go

@@ -13,7 +13,7 @@ type ConsumerMetadataResponse struct {
 	CoordinatorPort int32  // deprecated: use Coordinator.Addr()
 }
 
-func (r *ConsumerMetadataResponse) decode(pd packetDecoder) (err error) {
+func (r *ConsumerMetadataResponse) decode(pd packetDecoder, version int16) (err error) {
 	tmp, err := pd.getInt16()
 	if err != nil {
 		return err
@@ -71,3 +71,11 @@ func (r *ConsumerMetadataResponse) encode(pe packetEncoder) error {
 	pe.putInt32(r.CoordinatorPort)
 	return nil
 }
+
+func (r *ConsumerMetadataResponse) key() int16 {
+	return 10
+}
+
+func (r *ConsumerMetadataResponse) version() int16 {
+	return 0
+}

describe_groups_request.go

@@ -8,7 +8,7 @@ func (r *DescribeGroupsRequest) encode(pe packetEncoder) error {
 	return pe.putStringArray(r.Groups)
 }
 
-func (r *DescribeGroupsRequest) decode(pd packetDecoder) (err error) {
+func (r *DescribeGroupsRequest) decode(pd packetDecoder, version int16) (err error) {
 	r.Groups, err = pd.getStringArray()
 	return
 }

describe_groups_response.go

@@ -18,7 +18,7 @@ func (r *DescribeGroupsResponse) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *DescribeGroupsResponse) decode(pd packetDecoder) (err error) {
+func (r *DescribeGroupsResponse) decode(pd packetDecoder, version int16) (err error) {
 	n, err := pd.getArrayLength()
 	if err != nil {
 		return err
@@ -35,6 +35,14 @@ func (r *DescribeGroupsResponse) decode(pd packetDecoder) (err error) {
 	return nil
 }
 
+func (r *DescribeGroupsResponse) key() int16 {
+	return 15
+}
+
+func (r *DescribeGroupsResponse) version() int16 {
+	return 0
+}
+
 type GroupDescription struct {
 	Err          KError
 	GroupId      string

describe_groups_response_test.go

@@ -38,13 +38,13 @@ func TestDescribeGroupsResponse(t *testing.T) {
 	var response *DescribeGroupsResponse
 
 	response = new(DescribeGroupsResponse)
-	testDecodable(t, "empty", response, describeGroupsResponseEmpty)
+	testVersionDecodable(t, "empty", response, describeGroupsResponseEmpty, 0)
 	if len(response.Groups) != 0 {
 		t.Error("Expected no groups")
 	}
 
 	response = new(DescribeGroupsResponse)
-	testDecodable(t, "populated", response, describeGroupsResponsePopulated)
+	testVersionDecodable(t, "populated", response, describeGroupsResponsePopulated, 0)
 	if len(response.Groups) != 2 {
 		t.Error("Expected two groups")
 	}

encoder_decoder.go

@@ -41,6 +41,10 @@ type decoder interface {
 	decode(pd packetDecoder) error
 }
 
+type versionedDecoder interface {
+	decode(pd packetDecoder, version int16) error
+}
+
 // Decode takes bytes and a Decoder and fills the fields of the decoder from the bytes,
 // interpreted using Kafka's encoding rules.
 func decode(buf []byte, in decoder) error {
@@ -60,3 +64,21 @@ func decode(buf []byte, in decoder) error {
 
 	return nil
 }
+
+func versionedDecode(buf []byte, in versionedDecoder, version int16) error {
+	if buf == nil {
+		return nil
+	}
+
+	helper := realDecoder{raw: buf}
+	err := in.decode(&helper, version)
+	if err != nil {
+		return err
+	}
+
+	if helper.off != len(buf) {
+		return PacketDecodingError{"invalid length"}
+	}
+
+	return nil
+}

fetch_request.go

@@ -55,7 +55,7 @@ func (f *FetchRequest) encode(pe packetEncoder) (err error) {
 	return nil
 }
 
-func (f *FetchRequest) decode(pd packetDecoder) (err error) {
+func (f *FetchRequest) decode(pd packetDecoder, version int16) (err error) {
 	if _, err = pd.getInt32(); err != nil {
 		return err
 	}

fetch_response.go

@@ -49,7 +49,7 @@ func (pr *FetchResponseBlock) encode(pe packetEncoder) (err error) {
 	return pe.pop()
 }
 
-func (fr *FetchResponse) decode(pd packetDecoder) (err error) {
+func (fr *FetchResponse) decode(pd packetDecoder, version int16) (err error) {
 	numTopics, err := pd.getArrayLength()
 	if err != nil {
 		return err
@@ -116,6 +116,14 @@ func (fr *FetchResponse) encode(pe packetEncoder) (err error) {
 	return nil
 }
 
+func (r *FetchResponse) key() int16 {
+	return 1
+}
+
+func (r *FetchResponse) version() int16 {
+	return 0
+}
+
 func (fr *FetchResponse) GetBlock(topic string, partition int32) *FetchResponseBlock {
 	if fr.Blocks == nil {
 		return nil

fetch_response_test.go

@@ -30,7 +30,7 @@ var (
 
 func TestEmptyFetchResponse(t *testing.T) {
 	response := FetchResponse{}
-	testDecodable(t, "empty", &response, emptyFetchResponse)
+	testVersionDecodable(t, "empty", &response, emptyFetchResponse, 0)
 
 	if len(response.Blocks) != 0 {
 		t.Error("Decoding produced topic blocks where there were none.")
@@ -40,7 +40,7 @@ func TestEmptyFetchResponse(t *testing.T) {
 
 func TestOneMessageFetchResponse(t *testing.T) {
 	response := FetchResponse{}
-	testDecodable(t, "one message", &response, oneMessageFetchResponse)
+	testVersionDecodable(t, "one message", &response, oneMessageFetchResponse, 0)
 
 	if len(response.Blocks) != 1 {
 		t.Fatal("Decoding produced incorrect number of topic blocks.")

heartbeat_request.go

@@ -20,7 +20,7 @@ func (r *HeartbeatRequest) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *HeartbeatRequest) decode(pd packetDecoder) (err error) {
+func (r *HeartbeatRequest) decode(pd packetDecoder, version int16) (err error) {
 	if r.GroupId, err = pd.getString(); err != nil {
 		return
 	}

heartbeat_response.go

@@ -9,7 +9,7 @@ func (r *HeartbeatResponse) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *HeartbeatResponse) decode(pd packetDecoder) error {
+func (r *HeartbeatResponse) decode(pd packetDecoder, version int16) error {
 	if kerr, err := pd.getInt16(); err != nil {
 		return err
 	} else {
@@ -18,3 +18,11 @@ func (r *HeartbeatResponse) decode(pd packetDecoder) error {
 
 	return nil
 }
+
+func (r *HeartbeatResponse) key() int16 {
+	return 12
+}
+
+func (r *HeartbeatResponse) version() int16 {
+	return 0
+}

heartbeat_response_test.go

@@ -11,7 +11,7 @@ func TestHeartbeatResponse(t *testing.T) {
 	var response *HeartbeatResponse
 
 	response = new(HeartbeatResponse)
-	testDecodable(t, "no error", response, heartbeatResponseNoError)
+	testVersionDecodable(t, "no error", response, heartbeatResponseNoError, 0)
 	if response.Err != ErrNoError {
 		t.Error("Decoding error failed: no error expected but found", response.Err)
 	}

join_group_request.go

@@ -35,7 +35,7 @@ func (r *JoinGroupRequest) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *JoinGroupRequest) decode(pd packetDecoder) (err error) {
+func (r *JoinGroupRequest) decode(pd packetDecoder, version int16) (err error) {
 	if r.GroupId, err = pd.getString(); err != nil {
 		return
 	}

join_group_response.go

@@ -52,7 +52,7 @@ func (r *JoinGroupResponse) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *JoinGroupResponse) decode(pd packetDecoder) (err error) {
+func (r *JoinGroupResponse) decode(pd packetDecoder, version int16) (err error) {
 	if kerr, err := pd.getInt16(); err != nil {
 		return err
 	} else {
@@ -100,3 +100,11 @@ func (r *JoinGroupResponse) decode(pd packetDecoder) (err error) {
 
 	return nil
 }
+
+func (r *JoinGroupResponse) key() int16 {
+	return 11
+}
+
+func (r *JoinGroupResponse) version() int16 {
+	return 0
+}

join_group_response_test.go

@@ -40,7 +40,7 @@ func TestJoinGroupResponse(t *testing.T) {
 	var response *JoinGroupResponse
 
 	response = new(JoinGroupResponse)
-	testDecodable(t, "no error", response, joinGroupResponseNoError)
+	testVersionDecodable(t, "no error", response, joinGroupResponseNoError, 0)
 	if response.Err != ErrNoError {
 		t.Error("Decoding Err failed: no error expected but found", response.Err)
 	}
@@ -58,7 +58,7 @@ func TestJoinGroupResponse(t *testing.T) {
 	}
 
 	response = new(JoinGroupResponse)
-	testDecodable(t, "with error", response, joinGroupResponseWithError)
+	testVersionDecodable(t, "with error", response, joinGroupResponseWithError, 0)
 	if response.Err != ErrInconsistentGroupProtocol {
 		t.Error("Decoding Err failed: ErrInconsistentGroupProtocol expected but found", response.Err)
 	}
@@ -76,7 +76,7 @@ func TestJoinGroupResponse(t *testing.T) {
 	}
 
 	response = new(JoinGroupResponse)
-	testDecodable(t, "with error", response, joinGroupResponseLeader)
+	testVersionDecodable(t, "with error", response, joinGroupResponseLeader, 0)
 	if response.Err != ErrNoError {
 		t.Error("Decoding Err failed: ErrNoError expected but found", response.Err)
 	}

leave_group_request.go

@@ -16,7 +16,7 @@ func (r *LeaveGroupRequest) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *LeaveGroupRequest) decode(pd packetDecoder) (err error) {
+func (r *LeaveGroupRequest) decode(pd packetDecoder, version int16) (err error) {
 	if r.GroupId, err = pd.getString(); err != nil {
 		return
 	}

leave_group_response.go

@@ -9,7 +9,7 @@ func (r *LeaveGroupResponse) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *LeaveGroupResponse) decode(pd packetDecoder) (err error) {
+func (r *LeaveGroupResponse) decode(pd packetDecoder, version int16) (err error) {
 	if kerr, err := pd.getInt16(); err != nil {
 		return err
 	} else {
@@ -18,3 +18,11 @@ func (r *LeaveGroupResponse) decode(pd packetDecoder) (err error) {
 
 	return nil
 }
+
+func (r *LeaveGroupResponse) key() int16 {
+	return 13
+}
+
+func (r *LeaveGroupResponse) version() int16 {
+	return 0
+}

leave_group_response_test.go

@@ -11,13 +11,13 @@ func TestLeaveGroupResponse(t *testing.T) {
 	var response *LeaveGroupResponse
 
 	response = new(LeaveGroupResponse)
-	testDecodable(t, "no error", response, leaveGroupResponseNoError)
+	testVersionDecodable(t, "no error", response, leaveGroupResponseNoError, 0)
 	if response.Err != ErrNoError {
 		t.Error("Decoding error failed: no error expected but found", response.Err)
 	}
 
 	response = new(LeaveGroupResponse)
-	testDecodable(t, "with error", response, leaveGroupResponseWithError)
+	testVersionDecodable(t, "with error", response, leaveGroupResponseWithError, 0)
 	if response.Err != ErrUnknownMemberId {
 		t.Error("Decoding error failed: ErrUnknownMemberId expected but found", response.Err)
 	}

list_groups_request.go

@@ -7,7 +7,7 @@ func (r *ListGroupsRequest) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *ListGroupsRequest) decode(pd packetDecoder) (err error) {
+func (r *ListGroupsRequest) decode(pd packetDecoder, version int16) (err error) {
 	return nil
 }
 

list_groups_response.go

@@ -23,7 +23,7 @@ func (r *ListGroupsResponse) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *ListGroupsResponse) decode(pd packetDecoder) error {
+func (r *ListGroupsResponse) decode(pd packetDecoder, version int16) error {
 	if kerr, err := pd.getInt16(); err != nil {
 		return err
 	} else {
@@ -54,3 +54,11 @@ func (r *ListGroupsResponse) decode(pd packetDecoder) error {
 
 	return nil
 }
+
+func (r *ListGroupsResponse) key() int16 {
+	return 16
+}
+
+func (r *ListGroupsResponse) version() int16 {
+	return 0
+}

list_groups_response_test.go

@@ -27,7 +27,7 @@ func TestListGroupsResponse(t *testing.T) {
 	var response *ListGroupsResponse
 
 	response = new(ListGroupsResponse)
-	testDecodable(t, "no error", response, listGroupsResponseEmpty)
+	testVersionDecodable(t, "no error", response, listGroupsResponseEmpty, 0)
 	if response.Err != ErrNoError {
 		t.Error("Expected no gerror, found:", response.Err)
 	}
@@ -36,7 +36,7 @@ func TestListGroupsResponse(t *testing.T) {
 	}
 
 	response = new(ListGroupsResponse)
-	testDecodable(t, "no error", response, listGroupsResponseError)
+	testVersionDecodable(t, "no error", response, listGroupsResponseError, 0)
 	if response.Err != ErrClusterAuthorizationFailed {
 		t.Error("Expected no gerror, found:", response.Err)
 	}
@@ -45,7 +45,7 @@ func TestListGroupsResponse(t *testing.T) {
 	}
 
 	response = new(ListGroupsResponse)
-	testDecodable(t, "no error", response, listGroupsResponseWithConsumer)
+	testVersionDecodable(t, "no error", response, listGroupsResponseWithConsumer, 0)
 	if response.Err != ErrNoError {
 		t.Error("Expected no gerror, found:", response.Err)
 	}

metadata_request.go

@@ -19,7 +19,7 @@ func (mr *MetadataRequest) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (mr *MetadataRequest) decode(pd packetDecoder) error {
+func (mr *MetadataRequest) decode(pd packetDecoder, version int16) error {
 	topicCount, err := pd.getArrayLength()
 	if err != nil {
 		return err

metadata_response.go

@@ -118,7 +118,7 @@ type MetadataResponse struct {
 	Topics  []*TopicMetadata
 }
 
-func (m *MetadataResponse) decode(pd packetDecoder) (err error) {
+func (m *MetadataResponse) decode(pd packetDecoder, version int16) (err error) {
 	n, err := pd.getArrayLength()
 	if err != nil {
 		return err
@@ -176,6 +176,14 @@ func (m *MetadataResponse) encode(pe packetEncoder) error {
 	return nil
 }
 
+func (r *MetadataResponse) key() int16 {
+	return 3
+}
+
+func (r *MetadataResponse) version() int16 {
+	return 0
+}
+
 // testing API
 
 func (m *MetadataResponse) AddBroker(addr string, id int32) {

metadata_response_test.go

@@ -41,7 +41,7 @@ var (
 func TestEmptyMetadataResponse(t *testing.T) {
 	response := MetadataResponse{}
 
-	testDecodable(t, "empty", &response, emptyMetadataResponse)
+	testVersionDecodable(t, "empty", &response, emptyMetadataResponse, 0)
 	if len(response.Brokers) != 0 {
 		t.Error("Decoding produced", len(response.Brokers), "brokers where there were none!")
 	}
@@ -53,7 +53,7 @@ func TestEmptyMetadataResponse(t *testing.T) {
 func TestMetadataResponseWithBrokers(t *testing.T) {
 	response := MetadataResponse{}
 
-	testDecodable(t, "brokers, no topics", &response, brokersNoTopicsMetadataResponse)
+	testVersionDecodable(t, "brokers, no topics", &response, brokersNoTopicsMetadataResponse, 0)
 	if len(response.Brokers) != 2 {
 		t.Fatal("Decoding produced", len(response.Brokers), "brokers where there were two!")
 	}
@@ -79,7 +79,7 @@ func TestMetadataResponseWithBrokers(t *testing.T) {
 func TestMetadataResponseWithTopics(t *testing.T) {
 	response := MetadataResponse{}
 
-	testDecodable(t, "topics, no brokers", &response, topicsNoBrokersMetadataResponse)
+	testVersionDecodable(t, "topics, no brokers", &response, topicsNoBrokersMetadataResponse, 0)
 	if len(response.Brokers) != 0 {
 		t.Error("Decoding produced", len(response.Brokers), "brokers where there were none!")
 	}

mockbroker.go

@@ -60,7 +60,7 @@ type MockBroker struct {
 
 // RequestResponse represents a Request/Response pair processed by MockBroker.
 type RequestResponse struct {
-	Request  requestBody
+	Request  protocolBody
 	Response encoder
 }
 

mockresponses.go

@@ -17,7 +17,7 @@ type TestReporter interface {
 // allows generating a response based on a request body. MockResponses are used
 // to program behavior of MockBroker in tests.
 type MockResponse interface {
-	For(reqBody decoder) (res encoder)
+	For(reqBody versionedDecoder) (res encoder)
 }
 
 // MockWrapper is a mock response builder that returns a particular concrete
@@ -26,7 +26,7 @@ type MockWrapper struct {
 	res encoder
 }
 
-func (mw *MockWrapper) For(reqBody decoder) (res encoder) {
+func (mw *MockWrapper) For(reqBody versionedDecoder) (res encoder) {
 	return mw.res
 }
 
@@ -58,7 +58,7 @@ func NewMockSequence(responses ...interface{}) *MockSequence {
 	return ms
 }
 
-func (mc *MockSequence) For(reqBody decoder) (res encoder) {
+func (mc *MockSequence) For(reqBody versionedDecoder) (res encoder) {
 	res = mc.responses[0].For(reqBody)
 	if len(mc.responses) > 1 {
 		mc.responses = mc.responses[1:]
@@ -96,7 +96,7 @@ func (mmr *MockMetadataResponse) SetBroker(addr string, brokerID int32) *MockMet
 	return mmr
 }
 
-func (mmr *MockMetadataResponse) For(reqBody decoder) encoder {
+func (mmr *MockMetadataResponse) For(reqBody versionedDecoder) encoder {
 	metadataRequest := reqBody.(*MetadataRequest)
 	metadataResponse := &MetadataResponse{}
 	for addr, brokerID := range mmr.brokers {
@@ -146,7 +146,7 @@ func (mor *MockOffsetResponse) SetOffset(topic string, partition int32, time, of
 	return mor
 }
 
-func (mor *MockOffsetResponse) For(reqBody decoder) encoder {
+func (mor *MockOffsetResponse) For(reqBody versionedDecoder) encoder {
 	offsetRequest := reqBody.(*OffsetRequest)
 	offsetResponse := &OffsetResponse{}
 	for topic, partitions := range offsetRequest.blocks {
@@ -216,7 +216,7 @@ func (mfr *MockFetchResponse) SetHighWaterMark(topic string, partition int32, of
 	return mfr
 }
 
-func (mfr *MockFetchResponse) For(reqBody decoder) encoder {
+func (mfr *MockFetchResponse) For(reqBody versionedDecoder) encoder {
 	fetchRequest := reqBody.(*FetchRequest)
 	res := &FetchResponse{}
 	for topic, partitions := range fetchRequest.blocks {
@@ -298,7 +298,7 @@ func (mr *MockConsumerMetadataResponse) SetError(group string, kerror KError) *M
 	return mr
 }
 
-func (mr *MockConsumerMetadataResponse) For(reqBody decoder) encoder {
+func (mr *MockConsumerMetadataResponse) For(reqBody versionedDecoder) encoder {
 	req := reqBody.(*ConsumerMetadataRequest)
 	group := req.ConsumerGroup
 	res := &ConsumerMetadataResponse{}
@@ -340,7 +340,7 @@ func (mr *MockOffsetCommitResponse) SetError(group, topic string, partition int3
 	return mr
 }
 
-func (mr *MockOffsetCommitResponse) For(reqBody decoder) encoder {
+func (mr *MockOffsetCommitResponse) For(reqBody versionedDecoder) encoder {
 	req := reqBody.(*OffsetCommitRequest)
 	group := req.ConsumerGroup
 	res := &OffsetCommitResponse{}
@@ -391,7 +391,7 @@ func (mr *MockProduceResponse) SetError(topic string, partition int32, kerror KE
 	return mr
 }
 
-func (mr *MockProduceResponse) For(reqBody decoder) encoder {
+func (mr *MockProduceResponse) For(reqBody versionedDecoder) encoder {
 	req := reqBody.(*ProduceRequest)
 	res := &ProduceResponse{}
 	for topic, partitions := range req.msgSets {
@@ -442,7 +442,7 @@ func (mr *MockOffsetFetchResponse) SetOffset(group, topic string, partition int3
 	return mr
 }
 
-func (mr *MockOffsetFetchResponse) For(reqBody decoder) encoder {
+func (mr *MockOffsetFetchResponse) For(reqBody versionedDecoder) encoder {
 	req := reqBody.(*OffsetFetchRequest)
 	group := req.ConsumerGroup
 	res := &OffsetFetchResponse{}

offset_commit_request.go

@@ -103,7 +103,9 @@ func (r *OffsetCommitRequest) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *OffsetCommitRequest) decode(pd packetDecoder) (err error) {
+func (r *OffsetCommitRequest) decode(pd packetDecoder, version int16) (err error) {
+	r.Version = version
+
 	if r.ConsumerGroup, err = pd.getString(); err != nil {
 		return err
 	}

offset_commit_response.go

@@ -35,7 +35,7 @@ func (r *OffsetCommitResponse) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *OffsetCommitResponse) decode(pd packetDecoder) (err error) {
+func (r *OffsetCommitResponse) decode(pd packetDecoder, version int16) (err error) {
 	numTopics, err := pd.getArrayLength()
 	if err != nil || numTopics == 0 {
 		return err
@@ -71,3 +71,11 @@ func (r *OffsetCommitResponse) decode(pd packetDecoder) (err error) {
 
 	return nil
 }
+
+func (r *OffsetCommitResponse) key() int16 {
+	return 8
+}
+
+func (r *OffsetCommitResponse) version() int16 {
+	return 0
+}

offset_fetch_request.go

@@ -28,7 +28,8 @@ func (r *OffsetFetchRequest) encode(pe packetEncoder) (err error) {
 	return nil
 }
 
-func (r *OffsetFetchRequest) decode(pd packetDecoder) (err error) {
+func (r *OffsetFetchRequest) decode(pd packetDecoder, version int16) (err error) {
+	r.Version = version
 	if r.ConsumerGroup, err = pd.getString(); err != nil {
 		return err
 	}

offset_fetch_response.go

@@ -64,7 +64,7 @@ func (r *OffsetFetchResponse) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *OffsetFetchResponse) decode(pd packetDecoder) (err error) {
+func (r *OffsetFetchResponse) decode(pd packetDecoder, version int16) (err error) {
 	numTopics, err := pd.getArrayLength()
 	if err != nil || numTopics == 0 {
 		return err
@@ -106,6 +106,14 @@ func (r *OffsetFetchResponse) decode(pd packetDecoder) (err error) {
 	return nil
 }
 
+func (r *OffsetFetchResponse) key() int16 {
+	return 9
+}
+
+func (r *OffsetFetchResponse) version() int16 {
+	return 0
+}
+
 func (r *OffsetFetchResponse) GetBlock(topic string, partition int32) *OffsetFetchResponseBlock {
 	if r.Blocks == nil {
 		return nil

offset_request.go

@@ -50,7 +50,7 @@ func (r *OffsetRequest) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *OffsetRequest) decode(pd packetDecoder) error {
+func (r *OffsetRequest) decode(pd packetDecoder, version int16) error {
 	// Ignore replica ID
 	if _, err := pd.getInt32(); err != nil {
 		return err

offset_response.go

@@ -27,7 +27,7 @@ type OffsetResponse struct {
 	Blocks map[string]map[int32]*OffsetResponseBlock
 }
 
-func (r *OffsetResponse) decode(pd packetDecoder) (err error) {
+func (r *OffsetResponse) decode(pd packetDecoder, version int16) (err error) {
 	numTopics, err := pd.getArrayLength()
 	if err != nil {
 		return err
@@ -115,6 +115,14 @@ func (r *OffsetResponse) encode(pe packetEncoder) (err error) {
 	return nil
 }
 
+func (r *OffsetResponse) key() int16 {
+	return 2
+}
+
+func (r *OffsetResponse) version() int16 {
+	return 0
+}
+
 // testing API
 
 func (r *OffsetResponse) AddTopicPartition(topic string, partition int32, offset int64) {

offset_response_test.go

@@ -24,7 +24,7 @@ var (
 func TestEmptyOffsetResponse(t *testing.T) {
 	response := OffsetResponse{}
 
-	testDecodable(t, "empty", &response, emptyOffsetResponse)
+	testVersionDecodable(t, "empty", &response, emptyOffsetResponse, 0)
 	if len(response.Blocks) != 0 {
 		t.Error("Decoding produced", len(response.Blocks), "topics where there were none.")
 	}
@@ -33,7 +33,7 @@ func TestEmptyOffsetResponse(t *testing.T) {
 func TestNormalOffsetResponse(t *testing.T) {
 	response := OffsetResponse{}
 
-	testDecodable(t, "normal", &response, normalOffsetResponse)
+	testVersionDecodable(t, "normal", &response, normalOffsetResponse, 0)
 
 	if len(response.Blocks) != 2 {
 		t.Fatal("Decoding produced", len(response.Blocks), "topics where there were two.")

produce_request.go

@@ -54,7 +54,7 @@ func (p *ProduceRequest) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (p *ProduceRequest) decode(pd packetDecoder) error {
+func (p *ProduceRequest) decode(pd packetDecoder, version int16) error {
 	requiredAcks, err := pd.getInt16()
 	if err != nil {
 		return err

produce_response.go

@@ -24,7 +24,7 @@ type ProduceResponse struct {
 	Blocks map[string]map[int32]*ProduceResponseBlock
 }
 
-func (pr *ProduceResponse) decode(pd packetDecoder) (err error) {
+func (pr *ProduceResponse) decode(pd packetDecoder, version int16) (err error) {
 	numTopics, err := pd.getArrayLength()
 	if err != nil {
 		return err
@@ -85,6 +85,14 @@ func (pr *ProduceResponse) encode(pe packetEncoder) error {
 	return nil
 }
 
+func (r *ProduceResponse) key() int16 {
+	return 0
+}
+
+func (r *ProduceResponse) version() int16 {
+	return 0
+}
+
 func (pr *ProduceResponse) GetBlock(topic string, partition int32) *ProduceResponseBlock {
 	if pr.Blocks == nil {
 		return nil

produce_response_test.go

@@ -27,12 +27,12 @@ var (
 func TestProduceResponse(t *testing.T) {
 	response := ProduceResponse{}
 
-	testDecodable(t, "no blocks", &response, produceResponseNoBlocks)
+	testVersionDecodable(t, "no blocks", &response, produceResponseNoBlocks, 0)
 	if len(response.Blocks) != 0 {
 		t.Error("Decoding produced", len(response.Blocks), "topics where there were none")
 	}
 
-	testDecodable(t, "many blocks", &response, produceResponseManyBlocks)
+	testVersionDecodable(t, "many blocks", &response, produceResponseManyBlocks, 0)
 	if len(response.Blocks) != 2 {
 		t.Error("Decoding produced", len(response.Blocks), "topics where there were 2")
 	}

request.go

@@ -6,9 +6,9 @@ import (
 	"io"
 )
 
-type requestBody interface {
+type protocolBody interface {
 	encoder
-	decoder
+	versionedDecoder
 	key() int16
 	version() int16
 }
@@ -16,7 +16,7 @@ type requestBody interface {
 type request struct {
 	correlationID int32
 	clientID      string
-	body          requestBody
+	body          protocolBody
 }
 
 func (r *request) encode(pe packetEncoder) (err error) {
@@ -53,7 +53,7 @@ func (r *request) decode(pd packetDecoder) (err error) {
 	if r.body == nil {
 		return PacketDecodingError{fmt.Sprintf("unknown request key (%d)", key)}
 	}
-	return r.body.decode(pd)
+	return r.body.decode(pd, version)
 }
 
 func decodeRequest(r io.Reader) (req *request, err error) {
@@ -79,7 +79,7 @@ func decodeRequest(r io.Reader) (req *request, err error) {
 	return req, nil
 }
 
-func allocateBody(key, version int16) requestBody {
+func allocateBody(key, version int16) protocolBody {
 	switch key {
 	case 0:
 		return &ProduceRequest{}

request_test.go

@@ -40,7 +40,14 @@ func testDecodable(t *testing.T, name string, out decoder, in []byte) {
 	}
 }
 
-func testRequest(t *testing.T, name string, rb requestBody, expected []byte) {
+func testVersionDecodable(t *testing.T, name string, out versionedDecoder, in []byte, version int16) {
+	err := versionedDecode(in, out, version)
+	if err != nil {
+		t.Error("Decoding", name, "version", version, "failed:", err)
+	}
+}
+
+func testRequest(t *testing.T, name string, rb protocolBody, expected []byte) {
 	// Encoder request
 	req := &request{correlationID: 123, clientID: "foo", body: rb}
 	packet, err := encode(req)
@@ -61,7 +68,7 @@ func testRequest(t *testing.T, name string, rb requestBody, expected []byte) {
 	}
 }
 
-func testResponse(t *testing.T, name string, res encoder, expected []byte) {
+func testResponse(t *testing.T, name string, res protocolBody, expected []byte) {
 	encoded, err := encode(res)
 	if err != nil {
 		t.Error(err)
@@ -69,8 +76,8 @@ func testResponse(t *testing.T, name string, res encoder, expected []byte) {
 		t.Error("Encoding", name, "failed\ngot ", encoded, "\nwant", expected)
 	}
 
-	decoded := reflect.New(reflect.TypeOf(res).Elem()).Interface().(decoder)
-	if err := decode(encoded, decoded); err != nil {
+	decoded := reflect.New(reflect.TypeOf(res).Elem()).Interface().(versionedDecoder)
+	if err := versionedDecode(encoded, decoded, res.version()); err != nil {
 		t.Error("Decoding", name, "failed:", err)
 	}
 

sasl_handshake_request.go

@@ -12,7 +12,7 @@ func (r *SaslHandshakeRequest) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *SaslHandshakeRequest) decode(pd packetDecoder) (err error) {
+func (r *SaslHandshakeRequest) decode(pd packetDecoder, version int16) (err error) {
 	if r.Mechanism, err = pd.getString(); err != nil {
 		return err
 	}

sasl_handshake_response.go

@@ -10,7 +10,7 @@ func (r *SaslHandshakeResponse) encode(pe packetEncoder) error {
 	return pe.putStringArray(r.EnabledMechanisms)
 }
 
-func (r *SaslHandshakeResponse) decode(pd packetDecoder) error {
+func (r *SaslHandshakeResponse) decode(pd packetDecoder, version int16) error {
 	if kerr, err := pd.getInt16(); err != nil {
 		return err
 	} else {
@@ -24,3 +24,11 @@ func (r *SaslHandshakeResponse) decode(pd packetDecoder) error {
 
 	return nil
 }
+
+func (r *SaslHandshakeResponse) key() int16 {
+	return 17
+}
+
+func (r *SaslHandshakeResponse) version() int16 {
+	return 0
+}

sasl_handshake_response_test.go

@@ -14,7 +14,7 @@ func TestSaslHandshakeResponse(t *testing.T) {
 	var response *SaslHandshakeResponse
 
 	response = new(SaslHandshakeResponse)
-	testDecodable(t, "no error", response, saslHandshakeResponse)
+	testVersionDecodable(t, "no error", response, saslHandshakeResponse, 0)
 	if response.Err != ErrNoError {
 		t.Error("Decoding error failed: no error expected but found", response.Err)
 	}

sync_group_request.go

@@ -33,7 +33,7 @@ func (r *SyncGroupRequest) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *SyncGroupRequest) decode(pd packetDecoder) (err error) {
+func (r *SyncGroupRequest) decode(pd packetDecoder, version int16) (err error) {
 	if r.GroupId, err = pd.getString(); err != nil {
 		return
 	}

sync_group_response.go

@@ -16,7 +16,7 @@ func (r *SyncGroupResponse) encode(pe packetEncoder) error {
 	return pe.putBytes(r.MemberAssignment)
 }
 
-func (r *SyncGroupResponse) decode(pd packetDecoder) (err error) {
+func (r *SyncGroupResponse) decode(pd packetDecoder, version int16) (err error) {
 	if kerr, err := pd.getInt16(); err != nil {
 		return err
 	} else {
@@ -26,3 +26,11 @@ func (r *SyncGroupResponse) decode(pd packetDecoder) (err error) {
 	r.MemberAssignment, err = pd.getBytes()
 	return
 }
+
+func (r *SyncGroupResponse) key() int16 {
+	return 14
+}
+
+func (r *SyncGroupResponse) version() int16 {
+	return 0
+}

sync_group_response_test.go

@@ -21,7 +21,7 @@ func TestSyncGroupResponse(t *testing.T) {
 	var response *SyncGroupResponse
 
 	response = new(SyncGroupResponse)
-	testDecodable(t, "no error", response, syncGroupResponseNoError)
+	testVersionDecodable(t, "no error", response, syncGroupResponseNoError, 0)
 	if response.Err != ErrNoError {
 		t.Error("Decoding Err failed: no error expected but found", response.Err)
 	}
@@ -30,7 +30,7 @@ func TestSyncGroupResponse(t *testing.T) {
 	}
 
 	response = new(SyncGroupResponse)
-	testDecodable(t, "no error", response, syncGroupResponseWithError)
+	testVersionDecodable(t, "no error", response, syncGroupResponseWithError, 0)
 	if response.Err != ErrRebalanceInProgress {
 		t.Error("Decoding Err failed: ErrRebalanceInProgress expected but found", response.Err)
 	}