Opentracing support

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) {}

vendor/github.com/uber/jaeger-lib/metrics/factory.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
+
+// Factory creates new metrics
+type Factory interface {
+	Counter(name string, tags map[string]string) Counter
+	Timer(name string, tags map[string]string) Timer
+	Gauge(name string, tags map[string]string) Gauge
+
+	// Namespace returns a nested metrics factory.
+	Namespace(name string, tags map[string]string) Factory
+}
+
+// NullFactory is a metrics factory that returns NullCounter, NullTimer, and NullGauge.
+var NullFactory Factory = nullFactory{}
+
+type nullFactory struct{}
+
+func (nullFactory) Counter(name string, tags map[string]string) Counter   { return NullCounter }
+func (nullFactory) Timer(name string, tags map[string]string) Timer       { return NullTimer }
+func (nullFactory) Gauge(name string, tags map[string]string) Gauge       { return NullGauge }
+func (nullFactory) Namespace(name string, tags map[string]string) Factory { return NullFactory }

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) {}

vendor/github.com/uber/jaeger-lib/metrics/local.go

@@ -0,0 +1,332 @@
+// 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"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/codahale/hdrhistogram"
+)
+
+// This is intentionally very similar to github.com/codahale/metrics, the
+// main difference being that counters/gauges are scoped to the provider
+// rather than being global (to facilitate testing).
+
+// A LocalBackend is a metrics provider which aggregates data in-vm, and
+// allows exporting snapshots to shove the data into a remote collector
+type LocalBackend struct {
+	cm       sync.Mutex
+	gm       sync.Mutex
+	tm       sync.Mutex
+	counters map[string]*int64
+	gauges   map[string]*int64
+	timers   map[string]*localBackendTimer
+	stop     chan struct{}
+	wg       sync.WaitGroup
+	TagsSep  string
+	TagKVSep string
+}
+
+// NewLocalBackend returns a new LocalBackend. The collectionInterval is the histogram
+// time window for each timer.
+func NewLocalBackend(collectionInterval time.Duration) *LocalBackend {
+	b := &LocalBackend{
+		counters: make(map[string]*int64),
+		gauges:   make(map[string]*int64),
+		timers:   make(map[string]*localBackendTimer),
+		stop:     make(chan struct{}),
+		TagsSep:  "|",
+		TagKVSep: "=",
+	}
+	if collectionInterval == 0 {
+		// Use one histogram time window for all timers
+		return b
+	}
+	b.wg.Add(1)
+	go b.runLoop(collectionInterval)
+	return b
+}
+
+// Clear discards accumulated stats
+func (b *LocalBackend) Clear() {
+	b.cm.Lock()
+	defer b.cm.Unlock()
+	b.gm.Lock()
+	defer b.gm.Unlock()
+	b.tm.Lock()
+	defer b.tm.Unlock()
+	b.counters = make(map[string]*int64)
+	b.gauges = make(map[string]*int64)
+	b.timers = make(map[string]*localBackendTimer)
+}
+
+func (b *LocalBackend) runLoop(collectionInterval time.Duration) {
+	defer b.wg.Done()
+	ticker := time.NewTicker(collectionInterval)
+	for {
+		select {
+		case <-ticker.C:
+			b.tm.Lock()
+			timers := make(map[string]*localBackendTimer, len(b.timers))
+			for timerName, timer := range b.timers {
+				timers[timerName] = timer
+			}
+			b.tm.Unlock()
+
+			for _, t := range timers {
+				t.Lock()
+				t.hist.Rotate()
+				t.Unlock()
+			}
+		case <-b.stop:
+			ticker.Stop()
+			return
+		}
+	}
+}
+
+// IncCounter increments a counter value
+func (b *LocalBackend) IncCounter(name string, tags map[string]string, delta int64) {
+	name = GetKey(name, tags, b.TagsSep, b.TagKVSep)
+	b.cm.Lock()
+	defer b.cm.Unlock()
+	counter := b.counters[name]
+	if counter == nil {
+		b.counters[name] = new(int64)
+		*b.counters[name] = delta
+		return
+	}
+	atomic.AddInt64(counter, delta)
+}
+
+// UpdateGauge updates the value of a gauge
+func (b *LocalBackend) UpdateGauge(name string, tags map[string]string, value int64) {
+	name = GetKey(name, tags, b.TagsSep, b.TagKVSep)
+	b.gm.Lock()
+	defer b.gm.Unlock()
+	gauge := b.gauges[name]
+	if gauge == nil {
+		b.gauges[name] = new(int64)
+		*b.gauges[name] = value
+		return
+	}
+	atomic.StoreInt64(gauge, value)
+}
+
+// RecordTimer records a timing duration
+func (b *LocalBackend) RecordTimer(name string, tags map[string]string, d time.Duration) {
+	name = GetKey(name, tags, b.TagsSep, b.TagKVSep)
+	timer := b.findOrCreateTimer(name)
+	timer.Lock()
+	timer.hist.Current.RecordValue(int64(d / time.Millisecond))
+	timer.Unlock()
+}
+
+func (b *LocalBackend) findOrCreateTimer(name string) *localBackendTimer {
+	b.tm.Lock()
+	defer b.tm.Unlock()
+	if t, ok := b.timers[name]; ok {
+		return t
+	}
+
+	t := &localBackendTimer{
+		hist: hdrhistogram.NewWindowed(5, 0, int64((5*time.Minute)/time.Millisecond), 1),
+	}
+	b.timers[name] = t
+	return t
+}
+
+type localBackendTimer struct {
+	sync.Mutex
+	hist *hdrhistogram.WindowedHistogram
+}
+
+var (
+	percentiles = map[string]float64{
+		"P50":  50,
+		"P75":  75,
+		"P90":  90,
+		"P95":  95,
+		"P99":  99,
+		"P999": 99.9,
+	}
+)
+
+// Snapshot captures a snapshot of the current counter and gauge values
+func (b *LocalBackend) Snapshot() (counters, gauges map[string]int64) {
+	b.cm.Lock()
+	defer b.cm.Unlock()
+
+	counters = make(map[string]int64, len(b.counters))
+	for name, value := range b.counters {
+		counters[name] = atomic.LoadInt64(value)
+	}
+
+	b.gm.Lock()
+	defer b.gm.Unlock()
+
+	gauges = make(map[string]int64, len(b.gauges))
+	for name, value := range b.gauges {
+		gauges[name] = atomic.LoadInt64(value)
+	}
+
+	b.tm.Lock()
+	timers := make(map[string]*localBackendTimer)
+	for timerName, timer := range b.timers {
+		timers[timerName] = timer
+	}
+	b.tm.Unlock()
+
+	for timerName, timer := range timers {
+		timer.Lock()
+		hist := timer.hist.Merge()
+		timer.Unlock()
+		for name, q := range percentiles {
+			gauges[timerName+"."+name] = hist.ValueAtQuantile(q)
+		}
+	}
+
+	return
+}
+
+// Stop cleanly closes the background goroutine spawned by NewLocalBackend.
+func (b *LocalBackend) Stop() {
+	close(b.stop)
+	b.wg.Wait()
+}
+
+// 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
+}
+
+type stats struct {
+	name         string
+	tags         map[string]string
+	localBackend *LocalBackend
+}
+
+type localTimer struct {
+	stats
+}
+
+func (l *localTimer) Record(d time.Duration) {
+	l.localBackend.RecordTimer(l.name, l.tags, d)
+}
+
+type localCounter struct {
+	stats
+}
+
+func (l *localCounter) Inc(delta int64) {
+	l.localBackend.IncCounter(l.name, l.tags, delta)
+}
+
+type localGauge struct {
+	stats
+}
+
+func (l *localGauge) Update(value int64) {
+	l.localBackend.UpdateGauge(l.name, l.tags, value)
+}
+
+// LocalFactory stats factory that creates metrics that are stored locally
+type LocalFactory struct {
+	*LocalBackend
+	namespace string
+	tags      map[string]string
+}
+
+// NewLocalFactory returns a new LocalMetricsFactory
+func NewLocalFactory(collectionInterval time.Duration) *LocalFactory {
+	return &LocalFactory{
+		LocalBackend: NewLocalBackend(collectionInterval),
+	}
+}
+
+// appendTags adds the tags to the namespace tags and returns a combined map.
+func (l *LocalFactory) appendTags(tags map[string]string) map[string]string {
+	newTags := make(map[string]string)
+	for k, v := range l.tags {
+		newTags[k] = v
+	}
+	for k, v := range tags {
+		newTags[k] = v
+	}
+	return newTags
+}
+
+func (l *LocalFactory) newNamespace(name string) string {
+	if l.namespace == "" {
+		return name
+	}
+	return l.namespace + "." + name
+}
+
+// Counter returns a local stats counter
+func (l *LocalFactory) Counter(name string, tags map[string]string) Counter {
+	return &localCounter{
+		stats{
+			name:         l.newNamespace(name),
+			tags:         l.appendTags(tags),
+			localBackend: l.LocalBackend,
+		},
+	}
+}
+
+// Timer returns a local stats timer.
+func (l *LocalFactory) Timer(name string, tags map[string]string) Timer {
+	return &localTimer{
+		stats{
+			name:         l.newNamespace(name),
+			tags:         l.appendTags(tags),
+			localBackend: l.LocalBackend,
+		},
+	}
+}
+
+// Gauge returns a local stats gauge.
+func (l *LocalFactory) Gauge(name string, tags map[string]string) Gauge {
+	return &localGauge{
+		stats{
+			name:         l.newNamespace(name),
+			tags:         l.appendTags(tags),
+			localBackend: l.LocalBackend,
+		},
+	}
+}
+
+// Namespace returns a new namespace.
+func (l *LocalFactory) Namespace(name string, tags map[string]string) Factory {
+	return &LocalFactory{
+		namespace:    l.newNamespace(name),
+		tags:         l.appendTags(tags),
+		LocalBackend: l.LocalBackend,
+	}
+}

vendor/github.com/uber/jaeger-lib/metrics/metrics.go

@@ -0,0 +1,85 @@
+// 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"
+	"strings"
+)
+
+// Init initializes the passed in metrics and initializes its fields using the passed in factory.
+func Init(metrics interface{}, factory Factory, globalTags map[string]string) {
+	if err := initMetrics(metrics, factory, globalTags); err != nil {
+		panic(err.Error())
+	}
+}
+
+// initMetrics 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.
+func initMetrics(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()
+
+	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
+		}
+		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]
+			}
+		}
+		var obj interface{}
+		if field.Type.AssignableTo(counterPtrType) {
+			obj = factory.Counter(metric, tags)
+		} else if field.Type.AssignableTo(gaugePtrType) {
+			obj = factory.Gauge(metric, tags)
+		} else if field.Type.AssignableTo(timerPtrType) {
+			obj = factory.Timer(metric, tags)
+		} 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
+}

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)
+}

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) {}