diff --git a/vendor/github.com/uber/jaeger-lib/LICENSE b/vendor/github.com/uber/jaeger-lib/LICENSE
new file mode 100644
index 0000000..261eeb9
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-lib/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
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+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
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+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
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+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
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+   6. Trademarks. This License does not grant permission to use the trade
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+       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,
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diff --git a/vendor/github.com/uber/jaeger-lib/metrics/counter.go b/vendor/github.com/uber/jaeger-lib/metrics/counter.go
new file mode 100644
index 0000000..2a6a43e
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-lib/metrics/counter.go
@@ -0,0 +1,28 @@
+// 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 metrics
+
+// Counter tracks the number of times an event has occurred
+type Counter interface {
+	// Inc adds the given value to the counter.
+	Inc(int64)
+}
+
+// NullCounter counter that does nothing
+var NullCounter Counter = nullCounter{}
+
+type nullCounter struct{}
+
+func (nullCounter) Inc(int64) {}
diff --git a/vendor/github.com/uber/jaeger-lib/metrics/factory.go b/vendor/github.com/uber/jaeger-lib/metrics/factory.go
new file mode 100644
index 0000000..0ead061
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-lib/metrics/factory.go
@@ -0,0 +1,78 @@
+// 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 metrics
+
+import (
+	"time"
+)
+
+// NSOptions defines the name and tags map associated with a factory namespace
+type NSOptions struct {
+	Name string
+	Tags map[string]string
+}
+
+// Options defines the information associated with a metric
+type Options struct {
+	Name string
+	Tags map[string]string
+	Help string
+}
+
+// TimerOptions defines the information associated with a metric
+type TimerOptions struct {
+	Name    string
+	Tags    map[string]string
+	Help    string
+	Buckets []time.Duration
+}
+
+// HistogramOptions defines the information associated with a metric
+type HistogramOptions struct {
+	Name    string
+	Tags    map[string]string
+	Help    string
+	Buckets []float64
+}
+
+// Factory creates new metrics
+type Factory interface {
+	Counter(metric Options) Counter
+	Timer(metric TimerOptions) Timer
+	Gauge(metric Options) Gauge
+	Histogram(metric HistogramOptions) Histogram
+
+	// Namespace returns a nested metrics factory.
+	Namespace(scope NSOptions) Factory
+}
+
+// NullFactory is a metrics factory that returns NullCounter, NullTimer, and NullGauge.
+var NullFactory Factory = nullFactory{}
+
+type nullFactory struct{}
+
+func (nullFactory) Counter(options Options) Counter {
+	return NullCounter
+}
+func (nullFactory) Timer(options TimerOptions) Timer {
+	return NullTimer
+}
+func (nullFactory) Gauge(options Options) Gauge {
+	return NullGauge
+}
+func (nullFactory) Histogram(options HistogramOptions) Histogram {
+	return NullHistogram
+}
+func (nullFactory) Namespace(scope NSOptions) Factory { return NullFactory }
diff --git a/vendor/github.com/uber/jaeger-lib/metrics/gauge.go b/vendor/github.com/uber/jaeger-lib/metrics/gauge.go
new file mode 100644
index 0000000..3c60639
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-lib/metrics/gauge.go
@@ -0,0 +1,28 @@
+// 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 metrics
+
+// Gauge returns instantaneous measurements of something as an int64 value
+type Gauge interface {
+	// Update the gauge to the value passed in.
+	Update(int64)
+}
+
+// NullGauge gauge that does nothing
+var NullGauge Gauge = nullGauge{}
+
+type nullGauge struct{}
+
+func (nullGauge) Update(int64) {}
diff --git a/vendor/github.com/uber/jaeger-lib/metrics/histogram.go b/vendor/github.com/uber/jaeger-lib/metrics/histogram.go
new file mode 100644
index 0000000..d3bd617
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-lib/metrics/histogram.go
@@ -0,0 +1,28 @@
+// Copyright (c) 2018 The Jaeger Authors
+//
+// 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 metrics
+
+// Histogram that keeps track of a distribution of values.
+type Histogram interface {
+	// Records the value passed in.
+	Record(float64)
+}
+
+// NullHistogram that does nothing
+var NullHistogram Histogram = nullHistogram{}
+
+type nullHistogram struct{}
+
+func (nullHistogram) Record(float64) {}
diff --git a/vendor/github.com/uber/jaeger-lib/metrics/keys.go b/vendor/github.com/uber/jaeger-lib/metrics/keys.go
new file mode 100644
index 0000000..c24445a
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-lib/metrics/keys.go
@@ -0,0 +1,35 @@
+// 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 metrics
+
+import (
+	"sort"
+)
+
+// GetKey converts name+tags into a single string of the form
+// "name|tag1=value1|...|tagN=valueN", where tag names are
+// sorted alphabetically.
+func GetKey(name string, tags map[string]string, tagsSep string, tagKVSep string) string {
+	keys := make([]string, 0, len(tags))
+	for k := range tags {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	key := name
+	for _, k := range keys {
+		key = key + tagsSep + k + tagKVSep + tags[k]
+	}
+	return key
+}
diff --git a/vendor/github.com/uber/jaeger-lib/metrics/metrics.go b/vendor/github.com/uber/jaeger-lib/metrics/metrics.go
new file mode 100644
index 0000000..0df0c66
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-lib/metrics/metrics.go
@@ -0,0 +1,137 @@
+// 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 metrics
+
+import (
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+)
+
+// MustInit initializes the passed in metrics and initializes its fields using the passed in factory.
+//
+// It uses reflection to initialize a struct containing metrics fields
+// by assigning new Counter/Gauge/Timer values with the metric name retrieved
+// from the `metric` tag and stats tags retrieved from the `tags` tag.
+//
+// Note: all fields of the struct must be exported, have a `metric` tag, and be
+// of type Counter or Gauge or Timer.
+//
+// Errors during Init lead to a panic.
+func MustInit(metrics interface{}, factory Factory, globalTags map[string]string) {
+	if err := Init(metrics, factory, globalTags); err != nil {
+		panic(err.Error())
+	}
+}
+
+// Init does the same as MustInit, but returns an error instead of
+// panicking.
+func Init(m interface{}, factory Factory, globalTags map[string]string) error {
+	// Allow user to opt out of reporting metrics by passing in nil.
+	if factory == nil {
+		factory = NullFactory
+	}
+
+	counterPtrType := reflect.TypeOf((*Counter)(nil)).Elem()
+	gaugePtrType := reflect.TypeOf((*Gauge)(nil)).Elem()
+	timerPtrType := reflect.TypeOf((*Timer)(nil)).Elem()
+	histogramPtrType := reflect.TypeOf((*Histogram)(nil)).Elem()
+
+	v := reflect.ValueOf(m).Elem()
+	t := v.Type()
+	for i := 0; i < t.NumField(); i++ {
+		tags := make(map[string]string)
+		for k, v := range globalTags {
+			tags[k] = v
+		}
+		var buckets []float64
+		field := t.Field(i)
+		metric := field.Tag.Get("metric")
+		if metric == "" {
+			return fmt.Errorf("Field %s is missing a tag 'metric'", field.Name)
+		}
+		if tagString := field.Tag.Get("tags"); tagString != "" {
+			tagPairs := strings.Split(tagString, ",")
+			for _, tagPair := range tagPairs {
+				tag := strings.Split(tagPair, "=")
+				if len(tag) != 2 {
+					return fmt.Errorf(
+						"Field [%s]: Tag [%s] is not of the form key=value in 'tags' string [%s]",
+						field.Name, tagPair, tagString)
+				}
+				tags[tag[0]] = tag[1]
+			}
+		}
+		if bucketString := field.Tag.Get("buckets"); bucketString != "" {
+			if field.Type.AssignableTo(timerPtrType) {
+				// TODO: Parse timer duration buckets
+				return fmt.Errorf(
+					"Field [%s]: Buckets are not currently initialized for timer metrics",
+					field.Name)
+			} else if field.Type.AssignableTo(histogramPtrType) {
+				bucketValues := strings.Split(bucketString, ",")
+				for _, bucket := range bucketValues {
+					b, err := strconv.ParseFloat(bucket, 64)
+					if err != nil {
+						return fmt.Errorf(
+							"Field [%s]: Bucket [%s] could not be converted to float64 in 'buckets' string [%s]",
+							field.Name, bucket, bucketString)
+					}
+					buckets = append(buckets, b)
+				}
+			} else {
+				return fmt.Errorf(
+					"Field [%s]: Buckets should only be defined for Timer and Histogram metric types",
+					field.Name)
+			}
+		}
+		help := field.Tag.Get("help")
+		var obj interface{}
+		if field.Type.AssignableTo(counterPtrType) {
+			obj = factory.Counter(Options{
+				Name: metric,
+				Tags: tags,
+				Help: help,
+			})
+		} else if field.Type.AssignableTo(gaugePtrType) {
+			obj = factory.Gauge(Options{
+				Name: metric,
+				Tags: tags,
+				Help: help,
+			})
+		} else if field.Type.AssignableTo(timerPtrType) {
+			// TODO: Add buckets once parsed (see TODO above)
+			obj = factory.Timer(TimerOptions{
+				Name: metric,
+				Tags: tags,
+				Help: help,
+			})
+		} else if field.Type.AssignableTo(histogramPtrType) {
+			obj = factory.Histogram(HistogramOptions{
+				Name:    metric,
+				Tags:    tags,
+				Help:    help,
+				Buckets: buckets,
+			})
+		} else {
+			return fmt.Errorf(
+				"Field %s is not a pointer to timer, gauge, or counter",
+				field.Name)
+		}
+		v.Field(i).Set(reflect.ValueOf(obj))
+	}
+	return nil
+}
diff --git a/vendor/github.com/uber/jaeger-lib/metrics/stopwatch.go b/vendor/github.com/uber/jaeger-lib/metrics/stopwatch.go
new file mode 100644
index 0000000..4a8abdb
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-lib/metrics/stopwatch.go
@@ -0,0 +1,43 @@
+// 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 metrics
+
+import (
+	"time"
+)
+
+// StartStopwatch begins recording the executing time of an event, returning
+// a Stopwatch that should be used to stop the recording the time for
+// that event.  Multiple events can be occurring simultaneously each
+// represented by different active Stopwatches
+func StartStopwatch(timer Timer) Stopwatch {
+	return Stopwatch{t: timer, start: time.Now()}
+}
+
+// A Stopwatch tracks the execution time of a specific event
+type Stopwatch struct {
+	t     Timer
+	start time.Time
+}
+
+// Stop stops executing of the stopwatch and records the amount of elapsed time
+func (s Stopwatch) Stop() {
+	s.t.Record(s.ElapsedTime())
+}
+
+// ElapsedTime returns the amount of elapsed time (in time.Duration)
+func (s Stopwatch) ElapsedTime() time.Duration {
+	return time.Since(s.start)
+}
diff --git a/vendor/github.com/uber/jaeger-lib/metrics/timer.go b/vendor/github.com/uber/jaeger-lib/metrics/timer.go
new file mode 100644
index 0000000..e18d222
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-lib/metrics/timer.go
@@ -0,0 +1,33 @@
+// 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 metrics
+
+import (
+	"time"
+)
+
+// Timer accumulates observations about how long some operation took,
+// and also maintains a historgam of percentiles.
+type Timer interface {
+	// Records the time passed in.
+	Record(time.Duration)
+}
+
+// NullTimer timer that does nothing
+var NullTimer Timer = nullTimer{}
+
+type nullTimer struct{}
+
+func (nullTimer) Record(time.Duration) {}