Opentracing support

vendor/github.com/Shopify/sarama/request.go

@@ -0,0 +1,119 @@
+package sarama
+
+import (
+	"encoding/binary"
+	"fmt"
+	"io"
+)
+
+type protocolBody interface {
+	encoder
+	versionedDecoder
+	key() int16
+	version() int16
+	requiredVersion() KafkaVersion
+}
+
+type request struct {
+	correlationID int32
+	clientID      string
+	body          protocolBody
+}
+
+func (r *request) encode(pe packetEncoder) (err error) {
+	pe.push(&lengthField{})
+	pe.putInt16(r.body.key())
+	pe.putInt16(r.body.version())
+	pe.putInt32(r.correlationID)
+	err = pe.putString(r.clientID)
+	if err != nil {
+		return err
+	}
+	err = r.body.encode(pe)
+	if err != nil {
+		return err
+	}
+	return pe.pop()
+}
+
+func (r *request) decode(pd packetDecoder) (err error) {
+	var key int16
+	if key, err = pd.getInt16(); err != nil {
+		return err
+	}
+	var version int16
+	if version, err = pd.getInt16(); err != nil {
+		return err
+	}
+	if r.correlationID, err = pd.getInt32(); err != nil {
+		return err
+	}
+	r.clientID, err = pd.getString()
+
+	r.body = allocateBody(key, version)
+	if r.body == nil {
+		return PacketDecodingError{fmt.Sprintf("unknown request key (%d)", key)}
+	}
+	return r.body.decode(pd, version)
+}
+
+func decodeRequest(r io.Reader) (req *request, bytesRead int, err error) {
+	lengthBytes := make([]byte, 4)
+	if _, err := io.ReadFull(r, lengthBytes); err != nil {
+		return nil, bytesRead, err
+	}
+	bytesRead += len(lengthBytes)
+
+	length := int32(binary.BigEndian.Uint32(lengthBytes))
+	if length <= 4 || length > MaxRequestSize {
+		return nil, bytesRead, PacketDecodingError{fmt.Sprintf("message of length %d too large or too small", length)}
+	}
+
+	encodedReq := make([]byte, length)
+	if _, err := io.ReadFull(r, encodedReq); err != nil {
+		return nil, bytesRead, err
+	}
+	bytesRead += len(encodedReq)
+
+	req = &request{}
+	if err := decode(encodedReq, req); err != nil {
+		return nil, bytesRead, err
+	}
+	return req, bytesRead, nil
+}
+
+func allocateBody(key, version int16) protocolBody {
+	switch key {
+	case 0:
+		return &ProduceRequest{}
+	case 1:
+		return &FetchRequest{}
+	case 2:
+		return &OffsetRequest{Version: version}
+	case 3:
+		return &MetadataRequest{}
+	case 8:
+		return &OffsetCommitRequest{Version: version}
+	case 9:
+		return &OffsetFetchRequest{}
+	case 10:
+		return &ConsumerMetadataRequest{}
+	case 11:
+		return &JoinGroupRequest{}
+	case 12:
+		return &HeartbeatRequest{}
+	case 13:
+		return &LeaveGroupRequest{}
+	case 14:
+		return &SyncGroupRequest{}
+	case 15:
+		return &DescribeGroupsRequest{}
+	case 16:
+		return &ListGroupsRequest{}
+	case 17:
+		return &SaslHandshakeRequest{}
+	case 18:
+		return &ApiVersionsRequest{}
+	}
+	return nil
+}