diff --git a/vendor/github.com/uber/jaeger-client-go/zipkin_thrift_span.go b/vendor/github.com/uber/jaeger-client-go/zipkin_thrift_span.go
new file mode 100644
index 0000000..73aeb00
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-client-go/zipkin_thrift_span.go
@@ -0,0 +1,329 @@
+// Copyright (c) 2017 Uber Technologies, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package jaeger
+
+import (
+	"encoding/binary"
+	"fmt"
+	"time"
+
+	"github.com/opentracing/opentracing-go/ext"
+
+	"github.com/uber/jaeger-client-go/internal/spanlog"
+	z "github.com/uber/jaeger-client-go/thrift-gen/zipkincore"
+	"github.com/uber/jaeger-client-go/utils"
+)
+
+const (
+	// Zipkin UI does not work well with non-string tag values
+	allowPackedNumbers = false
+)
+
+var specialTagHandlers = map[string]func(*zipkinSpan, interface{}){
+	string(ext.SpanKind):     setSpanKind,
+	string(ext.PeerHostIPv4): setPeerIPv4,
+	string(ext.PeerPort):     setPeerPort,
+	string(ext.PeerService):  setPeerService,
+	TracerIPTagKey:           removeTag,
+}
+
+// BuildZipkinThrift builds thrift span based on internal span.
+// TODO: (breaking change) move to transport/zipkin and make private.
+func BuildZipkinThrift(s *Span) *z.Span {
+	span := &zipkinSpan{Span: s}
+	span.handleSpecialTags()
+	parentID := int64(span.context.parentID)
+	var ptrParentID *int64
+	if parentID != 0 {
+		ptrParentID = &parentID
+	}
+	traceIDHigh := int64(span.context.traceID.High)
+	var ptrTraceIDHigh *int64
+	if traceIDHigh != 0 {
+		ptrTraceIDHigh = &traceIDHigh
+	}
+	timestamp := utils.TimeToMicrosecondsSinceEpochInt64(span.startTime)
+	duration := span.duration.Nanoseconds() / int64(time.Microsecond)
+	endpoint := &z.Endpoint{
+		ServiceName: span.tracer.serviceName,
+		Ipv4:        int32(span.tracer.hostIPv4)}
+	thriftSpan := &z.Span{
+		TraceID:           int64(span.context.traceID.Low),
+		TraceIDHigh:       ptrTraceIDHigh,
+		ID:                int64(span.context.spanID),
+		ParentID:          ptrParentID,
+		Name:              span.operationName,
+		Timestamp:         &timestamp,
+		Duration:          &duration,
+		Debug:             span.context.IsDebug(),
+		Annotations:       buildAnnotations(span, endpoint),
+		BinaryAnnotations: buildBinaryAnnotations(span, endpoint)}
+	return thriftSpan
+}
+
+func buildAnnotations(span *zipkinSpan, endpoint *z.Endpoint) []*z.Annotation {
+	// automatically adding 2 Zipkin CoreAnnotations
+	annotations := make([]*z.Annotation, 0, 2+len(span.logs))
+	var startLabel, endLabel string
+	if span.spanKind == string(ext.SpanKindRPCClientEnum) {
+		startLabel, endLabel = z.CLIENT_SEND, z.CLIENT_RECV
+	} else if span.spanKind == string(ext.SpanKindRPCServerEnum) {
+		startLabel, endLabel = z.SERVER_RECV, z.SERVER_SEND
+	}
+	if !span.startTime.IsZero() && startLabel != "" {
+		start := &z.Annotation{
+			Timestamp: utils.TimeToMicrosecondsSinceEpochInt64(span.startTime),
+			Value:     startLabel,
+			Host:      endpoint}
+		annotations = append(annotations, start)
+		if span.duration != 0 {
+			endTs := span.startTime.Add(span.duration)
+			end := &z.Annotation{
+				Timestamp: utils.TimeToMicrosecondsSinceEpochInt64(endTs),
+				Value:     endLabel,
+				Host:      endpoint}
+			annotations = append(annotations, end)
+		}
+	}
+	for _, log := range span.logs {
+		anno := &z.Annotation{
+			Timestamp: utils.TimeToMicrosecondsSinceEpochInt64(log.Timestamp),
+			Host:      endpoint}
+		if content, err := spanlog.MaterializeWithJSON(log.Fields); err == nil {
+			anno.Value = truncateString(string(content), span.tracer.options.maxTagValueLength)
+		} else {
+			anno.Value = err.Error()
+		}
+		annotations = append(annotations, anno)
+	}
+	return annotations
+}
+
+func buildBinaryAnnotations(span *zipkinSpan, endpoint *z.Endpoint) []*z.BinaryAnnotation {
+	// automatically adding local component or server/client address tag, and client version
+	annotations := make([]*z.BinaryAnnotation, 0, 2+len(span.tags))
+
+	if span.peerDefined() && span.isRPC() {
+		peer := z.Endpoint{
+			Ipv4:        span.peer.Ipv4,
+			Port:        span.peer.Port,
+			ServiceName: span.peer.ServiceName}
+		label := z.CLIENT_ADDR
+		if span.isRPCClient() {
+			label = z.SERVER_ADDR
+		}
+		anno := &z.BinaryAnnotation{
+			Key:            label,
+			Value:          []byte{1},
+			AnnotationType: z.AnnotationType_BOOL,
+			Host:           &peer}
+		annotations = append(annotations, anno)
+	}
+	if !span.isRPC() {
+		componentName := endpoint.ServiceName
+		for _, tag := range span.tags {
+			if tag.key == string(ext.Component) {
+				componentName = stringify(tag.value)
+				break
+			}
+		}
+		local := &z.BinaryAnnotation{
+			Key:            z.LOCAL_COMPONENT,
+			Value:          []byte(componentName),
+			AnnotationType: z.AnnotationType_STRING,
+			Host:           endpoint}
+		annotations = append(annotations, local)
+	}
+	for _, tag := range span.tags {
+		// "Special tags" are already handled by this point, we'd be double reporting the
+		// tags if we don't skip here
+		if _, ok := specialTagHandlers[tag.key]; ok {
+			continue
+		}
+		if anno := buildBinaryAnnotation(tag.key, tag.value, span.tracer.options.maxTagValueLength, nil); anno != nil {
+			annotations = append(annotations, anno)
+		}
+	}
+	return annotations
+}
+
+func buildBinaryAnnotation(key string, val interface{}, maxTagValueLength int, endpoint *z.Endpoint) *z.BinaryAnnotation {
+	bann := &z.BinaryAnnotation{Key: key, Host: endpoint}
+	if value, ok := val.(string); ok {
+		bann.Value = []byte(truncateString(value, maxTagValueLength))
+		bann.AnnotationType = z.AnnotationType_STRING
+	} else if value, ok := val.([]byte); ok {
+		if len(value) > maxTagValueLength {
+			value = value[:maxTagValueLength]
+		}
+		bann.Value = value
+		bann.AnnotationType = z.AnnotationType_BYTES
+	} else if value, ok := val.(int32); ok && allowPackedNumbers {
+		bann.Value = int32ToBytes(value)
+		bann.AnnotationType = z.AnnotationType_I32
+	} else if value, ok := val.(int64); ok && allowPackedNumbers {
+		bann.Value = int64ToBytes(value)
+		bann.AnnotationType = z.AnnotationType_I64
+	} else if value, ok := val.(int); ok && allowPackedNumbers {
+		bann.Value = int64ToBytes(int64(value))
+		bann.AnnotationType = z.AnnotationType_I64
+	} else if value, ok := val.(bool); ok {
+		bann.Value = []byte{boolToByte(value)}
+		bann.AnnotationType = z.AnnotationType_BOOL
+	} else {
+		value := stringify(val)
+		bann.Value = []byte(truncateString(value, maxTagValueLength))
+		bann.AnnotationType = z.AnnotationType_STRING
+	}
+	return bann
+}
+
+func stringify(value interface{}) string {
+	if s, ok := value.(string); ok {
+		return s
+	}
+	return fmt.Sprintf("%+v", value)
+}
+
+func truncateString(value string, maxLength int) string {
+	// we ignore the problem of utf8 runes possibly being sliced in the middle,
+	// as it is rather expensive to iterate through each tag just to find rune
+	// boundaries.
+	if len(value) > maxLength {
+		return value[:maxLength]
+	}
+	return value
+}
+
+func boolToByte(b bool) byte {
+	if b {
+		return 1
+	}
+	return 0
+}
+
+// int32ToBytes converts int32 to bytes.
+func int32ToBytes(i int32) []byte {
+	buf := make([]byte, 4)
+	binary.BigEndian.PutUint32(buf, uint32(i))
+	return buf
+}
+
+// int64ToBytes converts int64 to bytes.
+func int64ToBytes(i int64) []byte {
+	buf := make([]byte, 8)
+	binary.BigEndian.PutUint64(buf, uint64(i))
+	return buf
+}
+
+type zipkinSpan struct {
+	*Span
+
+	// peer points to the peer service participating in this span,
+	// e.g. the Client if this span is a server span,
+	// or Server if this span is a client span
+	peer struct {
+		Ipv4        int32
+		Port        int16
+		ServiceName string
+	}
+
+	// used to distinguish local vs. RPC Server vs. RPC Client spans
+	spanKind string
+}
+
+func (s *zipkinSpan) handleSpecialTags() {
+	s.Lock()
+	defer s.Unlock()
+	if s.firstInProcess {
+		// append the process tags
+		s.tags = append(s.tags, s.tracer.tags...)
+	}
+	filteredTags := make([]Tag, 0, len(s.tags))
+	for _, tag := range s.tags {
+		if handler, ok := specialTagHandlers[tag.key]; ok {
+			handler(s, tag.value)
+		} else {
+			filteredTags = append(filteredTags, tag)
+		}
+	}
+	s.tags = filteredTags
+}
+
+func setSpanKind(s *zipkinSpan, value interface{}) {
+	if val, ok := value.(string); ok {
+		s.spanKind = val
+		return
+	}
+	if val, ok := value.(ext.SpanKindEnum); ok {
+		s.spanKind = string(val)
+	}
+}
+
+func setPeerIPv4(s *zipkinSpan, value interface{}) {
+	if val, ok := value.(string); ok {
+		if ip, err := utils.ParseIPToUint32(val); err == nil {
+			s.peer.Ipv4 = int32(ip)
+			return
+		}
+	}
+	if val, ok := value.(uint32); ok {
+		s.peer.Ipv4 = int32(val)
+		return
+	}
+	if val, ok := value.(int32); ok {
+		s.peer.Ipv4 = val
+	}
+}
+
+func setPeerPort(s *zipkinSpan, value interface{}) {
+	if val, ok := value.(string); ok {
+		if port, err := utils.ParsePort(val); err == nil {
+			s.peer.Port = int16(port)
+			return
+		}
+	}
+	if val, ok := value.(uint16); ok {
+		s.peer.Port = int16(val)
+		return
+	}
+	if val, ok := value.(int); ok {
+		s.peer.Port = int16(val)
+	}
+}
+
+func setPeerService(s *zipkinSpan, value interface{}) {
+	if val, ok := value.(string); ok {
+		s.peer.ServiceName = val
+	}
+}
+
+func removeTag(s *zipkinSpan, value interface{}) {}
+
+func (s *zipkinSpan) peerDefined() bool {
+	return s.peer.ServiceName != "" || s.peer.Ipv4 != 0 || s.peer.Port != 0
+}
+
+func (s *zipkinSpan) isRPC() bool {
+	s.RLock()
+	defer s.RUnlock()
+	return s.spanKind == string(ext.SpanKindRPCClientEnum) || s.spanKind == string(ext.SpanKindRPCServerEnum)
+}
+
+func (s *zipkinSpan) isRPCClient() bool {
+	s.RLock()
+	defer s.RUnlock()
+	return s.spanKind == string(ext.SpanKindRPCClientEnum)
+}