[VOL-3142] Update dependency of voltha-lib-go to include log package registration fix
Change-Id: I36890c7aa685e46721b481d5c965f9c0bc86934c
diff --git a/vendor/github.com/uber/jaeger-client-go/sampler.go b/vendor/github.com/uber/jaeger-client-go/sampler.go
new file mode 100644
index 0000000..d0be8ad
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-client-go/sampler.go
@@ -0,0 +1,516 @@
+// 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 (
+ "fmt"
+ "math"
+ "strings"
+ "sync"
+
+ "github.com/uber/jaeger-client-go/thrift-gen/sampling"
+ "github.com/uber/jaeger-client-go/utils"
+)
+
+const (
+ defaultMaxOperations = 2000
+)
+
+// Sampler decides whether a new trace should be sampled or not.
+type Sampler interface {
+ // IsSampled decides whether a trace with given `id` and `operation`
+ // should be sampled. This function will also return the tags that
+ // can be used to identify the type of sampling that was applied to
+ // the root span. Most simple samplers would return two tags,
+ // sampler.type and sampler.param, similar to those used in the Configuration
+ IsSampled(id TraceID, operation string) (sampled bool, tags []Tag)
+
+ // Close does a clean shutdown of the sampler, stopping any background
+ // go-routines it may have started.
+ Close()
+
+ // Equal checks if the `other` sampler is functionally equivalent
+ // to this sampler.
+ // TODO (breaking change) remove this function. See PerOperationSampler.Equals for explanation.
+ Equal(other Sampler) bool
+}
+
+// -----------------------
+
+// ConstSampler is a sampler that always makes the same decision.
+type ConstSampler struct {
+ legacySamplerV1Base
+ Decision bool
+ tags []Tag
+}
+
+// NewConstSampler creates a ConstSampler.
+func NewConstSampler(sample bool) *ConstSampler {
+ tags := []Tag{
+ {key: SamplerTypeTagKey, value: SamplerTypeConst},
+ {key: SamplerParamTagKey, value: sample},
+ }
+ s := &ConstSampler{
+ Decision: sample,
+ tags: tags,
+ }
+ s.delegate = s.IsSampled
+ return s
+}
+
+// IsSampled implements IsSampled() of Sampler.
+func (s *ConstSampler) IsSampled(id TraceID, operation string) (bool, []Tag) {
+ return s.Decision, s.tags
+}
+
+// Close implements Close() of Sampler.
+func (s *ConstSampler) Close() {
+ // nothing to do
+}
+
+// Equal implements Equal() of Sampler.
+func (s *ConstSampler) Equal(other Sampler) bool {
+ if o, ok := other.(*ConstSampler); ok {
+ return s.Decision == o.Decision
+ }
+ return false
+}
+
+// String is used to log sampler details.
+func (s *ConstSampler) String() string {
+ return fmt.Sprintf("ConstSampler(decision=%t)", s.Decision)
+}
+
+// -----------------------
+
+// ProbabilisticSampler is a sampler that randomly samples a certain percentage
+// of traces.
+type ProbabilisticSampler struct {
+ legacySamplerV1Base
+ samplingRate float64
+ samplingBoundary uint64
+ tags []Tag
+}
+
+const maxRandomNumber = ^(uint64(1) << 63) // i.e. 0x7fffffffffffffff
+
+// NewProbabilisticSampler creates a sampler that randomly samples a certain percentage of traces specified by the
+// samplingRate, in the range between 0.0 and 1.0.
+//
+// It relies on the fact that new trace IDs are 63bit random numbers themselves, thus making the sampling decision
+// without generating a new random number, but simply calculating if traceID < (samplingRate * 2^63).
+// TODO remove the error from this function for next major release
+func NewProbabilisticSampler(samplingRate float64) (*ProbabilisticSampler, error) {
+ if samplingRate < 0.0 || samplingRate > 1.0 {
+ return nil, fmt.Errorf("Sampling Rate must be between 0.0 and 1.0, received %f", samplingRate)
+ }
+ return newProbabilisticSampler(samplingRate), nil
+}
+
+func newProbabilisticSampler(samplingRate float64) *ProbabilisticSampler {
+ s := new(ProbabilisticSampler)
+ s.delegate = s.IsSampled
+ return s.init(samplingRate)
+}
+
+func (s *ProbabilisticSampler) init(samplingRate float64) *ProbabilisticSampler {
+ s.samplingRate = math.Max(0.0, math.Min(samplingRate, 1.0))
+ s.samplingBoundary = uint64(float64(maxRandomNumber) * s.samplingRate)
+ s.tags = []Tag{
+ {key: SamplerTypeTagKey, value: SamplerTypeProbabilistic},
+ {key: SamplerParamTagKey, value: s.samplingRate},
+ }
+ return s
+}
+
+// SamplingRate returns the sampling probability this sampled was constructed with.
+func (s *ProbabilisticSampler) SamplingRate() float64 {
+ return s.samplingRate
+}
+
+// IsSampled implements IsSampled() of Sampler.
+func (s *ProbabilisticSampler) IsSampled(id TraceID, operation string) (bool, []Tag) {
+ return s.samplingBoundary >= id.Low&maxRandomNumber, s.tags
+}
+
+// Close implements Close() of Sampler.
+func (s *ProbabilisticSampler) Close() {
+ // nothing to do
+}
+
+// Equal implements Equal() of Sampler.
+func (s *ProbabilisticSampler) Equal(other Sampler) bool {
+ if o, ok := other.(*ProbabilisticSampler); ok {
+ return s.samplingBoundary == o.samplingBoundary
+ }
+ return false
+}
+
+// Update modifies in-place the sampling rate. Locking must be done externally.
+func (s *ProbabilisticSampler) Update(samplingRate float64) error {
+ if samplingRate < 0.0 || samplingRate > 1.0 {
+ return fmt.Errorf("Sampling Rate must be between 0.0 and 1.0, received %f", samplingRate)
+ }
+ s.init(samplingRate)
+ return nil
+}
+
+// String is used to log sampler details.
+func (s *ProbabilisticSampler) String() string {
+ return fmt.Sprintf("ProbabilisticSampler(samplingRate=%v)", s.samplingRate)
+}
+
+// -----------------------
+
+// RateLimitingSampler samples at most maxTracesPerSecond. The distribution of sampled traces follows
+// burstiness of the service, i.e. a service with uniformly distributed requests will have those
+// requests sampled uniformly as well, but if requests are bursty, especially sub-second, then a
+// number of sequential requests can be sampled each second.
+type RateLimitingSampler struct {
+ legacySamplerV1Base
+ maxTracesPerSecond float64
+ rateLimiter *utils.ReconfigurableRateLimiter
+ tags []Tag
+}
+
+// NewRateLimitingSampler creates new RateLimitingSampler.
+func NewRateLimitingSampler(maxTracesPerSecond float64) *RateLimitingSampler {
+ s := new(RateLimitingSampler)
+ s.delegate = s.IsSampled
+ return s.init(maxTracesPerSecond)
+}
+
+func (s *RateLimitingSampler) init(maxTracesPerSecond float64) *RateLimitingSampler {
+ if s.rateLimiter == nil {
+ s.rateLimiter = utils.NewRateLimiter(maxTracesPerSecond, math.Max(maxTracesPerSecond, 1.0))
+ } else {
+ s.rateLimiter.Update(maxTracesPerSecond, math.Max(maxTracesPerSecond, 1.0))
+ }
+ s.maxTracesPerSecond = maxTracesPerSecond
+ s.tags = []Tag{
+ {key: SamplerTypeTagKey, value: SamplerTypeRateLimiting},
+ {key: SamplerParamTagKey, value: maxTracesPerSecond},
+ }
+ return s
+}
+
+// IsSampled implements IsSampled() of Sampler.
+func (s *RateLimitingSampler) IsSampled(id TraceID, operation string) (bool, []Tag) {
+ return s.rateLimiter.CheckCredit(1.0), s.tags
+}
+
+// Update reconfigures the rate limiter, while preserving its accumulated balance.
+// Locking must be done externally.
+func (s *RateLimitingSampler) Update(maxTracesPerSecond float64) {
+ if s.maxTracesPerSecond != maxTracesPerSecond {
+ s.init(maxTracesPerSecond)
+ }
+}
+
+// Close does nothing.
+func (s *RateLimitingSampler) Close() {
+ // nothing to do
+}
+
+// Equal compares with another sampler.
+func (s *RateLimitingSampler) Equal(other Sampler) bool {
+ if o, ok := other.(*RateLimitingSampler); ok {
+ return s.maxTracesPerSecond == o.maxTracesPerSecond
+ }
+ return false
+}
+
+// String is used to log sampler details.
+func (s *RateLimitingSampler) String() string {
+ return fmt.Sprintf("RateLimitingSampler(maxTracesPerSecond=%v)", s.maxTracesPerSecond)
+}
+
+// -----------------------
+
+// GuaranteedThroughputProbabilisticSampler is a sampler that leverages both ProbabilisticSampler and
+// RateLimitingSampler. The RateLimitingSampler is used as a guaranteed lower bound sampler such that
+// every operation is sampled at least once in a time interval defined by the lowerBound. ie a lowerBound
+// of 1.0 / (60 * 10) will sample an operation at least once every 10 minutes.
+//
+// The ProbabilisticSampler is given higher priority when tags are emitted, ie. if IsSampled() for both
+// samplers return true, the tags for ProbabilisticSampler will be used.
+type GuaranteedThroughputProbabilisticSampler struct {
+ probabilisticSampler *ProbabilisticSampler
+ lowerBoundSampler *RateLimitingSampler
+ tags []Tag
+ samplingRate float64
+ lowerBound float64
+}
+
+// NewGuaranteedThroughputProbabilisticSampler returns a delegating sampler that applies both
+// ProbabilisticSampler and RateLimitingSampler.
+func NewGuaranteedThroughputProbabilisticSampler(
+ lowerBound, samplingRate float64,
+) (*GuaranteedThroughputProbabilisticSampler, error) {
+ return newGuaranteedThroughputProbabilisticSampler(lowerBound, samplingRate), nil
+}
+
+func newGuaranteedThroughputProbabilisticSampler(lowerBound, samplingRate float64) *GuaranteedThroughputProbabilisticSampler {
+ s := &GuaranteedThroughputProbabilisticSampler{
+ lowerBoundSampler: NewRateLimitingSampler(lowerBound),
+ lowerBound: lowerBound,
+ }
+ s.setProbabilisticSampler(samplingRate)
+ return s
+}
+
+func (s *GuaranteedThroughputProbabilisticSampler) setProbabilisticSampler(samplingRate float64) {
+ if s.probabilisticSampler == nil {
+ s.probabilisticSampler = newProbabilisticSampler(samplingRate)
+ } else if s.samplingRate != samplingRate {
+ s.probabilisticSampler.init(samplingRate)
+ }
+ // since we don't validate samplingRate, sampler may have clamped it to [0, 1] interval
+ samplingRate = s.probabilisticSampler.SamplingRate()
+ if s.samplingRate != samplingRate || s.tags == nil {
+ s.samplingRate = s.probabilisticSampler.SamplingRate()
+ s.tags = []Tag{
+ {key: SamplerTypeTagKey, value: SamplerTypeLowerBound},
+ {key: SamplerParamTagKey, value: s.samplingRate},
+ }
+ }
+}
+
+// IsSampled implements IsSampled() of Sampler.
+func (s *GuaranteedThroughputProbabilisticSampler) IsSampled(id TraceID, operation string) (bool, []Tag) {
+ if sampled, tags := s.probabilisticSampler.IsSampled(id, operation); sampled {
+ s.lowerBoundSampler.IsSampled(id, operation)
+ return true, tags
+ }
+ sampled, _ := s.lowerBoundSampler.IsSampled(id, operation)
+ return sampled, s.tags
+}
+
+// Close implements Close() of Sampler.
+func (s *GuaranteedThroughputProbabilisticSampler) Close() {
+ s.probabilisticSampler.Close()
+ s.lowerBoundSampler.Close()
+}
+
+// Equal implements Equal() of Sampler.
+func (s *GuaranteedThroughputProbabilisticSampler) Equal(other Sampler) bool {
+ // NB The Equal() function is expensive and will be removed. See PerOperationSampler.Equal() for
+ // more information.
+ return false
+}
+
+// this function should only be called while holding a Write lock
+func (s *GuaranteedThroughputProbabilisticSampler) update(lowerBound, samplingRate float64) {
+ s.setProbabilisticSampler(samplingRate)
+ if s.lowerBound != lowerBound {
+ s.lowerBoundSampler.Update(lowerBound)
+ s.lowerBound = lowerBound
+ }
+}
+
+func (s GuaranteedThroughputProbabilisticSampler) String() string {
+ return fmt.Sprintf("GuaranteedThroughputProbabilisticSampler(lowerBound=%f, samplingRate=%f)", s.lowerBound, s.samplingRate)
+}
+
+// -----------------------
+
+// PerOperationSampler is a delegating sampler that applies GuaranteedThroughputProbabilisticSampler
+// on a per-operation basis.
+type PerOperationSampler struct {
+ sync.RWMutex
+
+ samplers map[string]*GuaranteedThroughputProbabilisticSampler
+ defaultSampler *ProbabilisticSampler
+ lowerBound float64
+ maxOperations int
+
+ // see description in PerOperationSamplerParams
+ operationNameLateBinding bool
+}
+
+// NewAdaptiveSampler returns a new PerOperationSampler.
+// Deprecated: please use NewPerOperationSampler.
+func NewAdaptiveSampler(strategies *sampling.PerOperationSamplingStrategies, maxOperations int) (*PerOperationSampler, error) {
+ return NewPerOperationSampler(PerOperationSamplerParams{
+ MaxOperations: maxOperations,
+ Strategies: strategies,
+ }), nil
+}
+
+// PerOperationSamplerParams defines parameters when creating PerOperationSampler.
+type PerOperationSamplerParams struct {
+ // Max number of operations that will be tracked. Other operations will be given default strategy.
+ MaxOperations int
+
+ // Opt-in feature for applications that require late binding of span name via explicit call to SetOperationName.
+ // When this feature is enabled, the sampler will return retryable=true from OnCreateSpan(), thus leaving
+ // the sampling decision as non-final (and the span as writeable). This may lead to degraded performance
+ // in applications that always provide the correct span name on trace creation.
+ //
+ // For backwards compatibility this option is off by default.
+ OperationNameLateBinding bool
+
+ // Initial configuration of the sampling strategies (usually retrieved from the backend by Remote Sampler).
+ Strategies *sampling.PerOperationSamplingStrategies
+}
+
+// NewPerOperationSampler returns a new PerOperationSampler.
+func NewPerOperationSampler(params PerOperationSamplerParams) *PerOperationSampler {
+ if params.MaxOperations <= 0 {
+ params.MaxOperations = defaultMaxOperations
+ }
+ samplers := make(map[string]*GuaranteedThroughputProbabilisticSampler)
+ for _, strategy := range params.Strategies.PerOperationStrategies {
+ sampler := newGuaranteedThroughputProbabilisticSampler(
+ params.Strategies.DefaultLowerBoundTracesPerSecond,
+ strategy.ProbabilisticSampling.SamplingRate,
+ )
+ samplers[strategy.Operation] = sampler
+ }
+ return &PerOperationSampler{
+ samplers: samplers,
+ defaultSampler: newProbabilisticSampler(params.Strategies.DefaultSamplingProbability),
+ lowerBound: params.Strategies.DefaultLowerBoundTracesPerSecond,
+ maxOperations: params.MaxOperations,
+ operationNameLateBinding: params.OperationNameLateBinding,
+ }
+}
+
+// IsSampled is not used and only exists to match Sampler V1 API.
+// TODO (breaking change) remove when upgrading everything to SamplerV2
+func (s *PerOperationSampler) IsSampled(id TraceID, operation string) (bool, []Tag) {
+ return false, nil
+}
+
+func (s *PerOperationSampler) trySampling(span *Span, operationName string) (bool, []Tag) {
+ samplerV1 := s.getSamplerForOperation(operationName)
+ var sampled bool
+ var tags []Tag
+ if span.context.samplingState.isLocalRootSpan(span.context.spanID) {
+ sampled, tags = samplerV1.IsSampled(span.context.TraceID(), operationName)
+ }
+ return sampled, tags
+}
+
+// OnCreateSpan implements OnCreateSpan of SamplerV2.
+func (s *PerOperationSampler) OnCreateSpan(span *Span) SamplingDecision {
+ sampled, tags := s.trySampling(span, span.OperationName())
+ return SamplingDecision{Sample: sampled, Retryable: s.operationNameLateBinding, Tags: tags}
+}
+
+// OnSetOperationName implements OnSetOperationName of SamplerV2.
+func (s *PerOperationSampler) OnSetOperationName(span *Span, operationName string) SamplingDecision {
+ sampled, tags := s.trySampling(span, operationName)
+ return SamplingDecision{Sample: sampled, Retryable: false, Tags: tags}
+}
+
+// OnSetTag implements OnSetTag of SamplerV2.
+func (s *PerOperationSampler) OnSetTag(span *Span, key string, value interface{}) SamplingDecision {
+ return SamplingDecision{Sample: false, Retryable: true}
+}
+
+// OnFinishSpan implements OnFinishSpan of SamplerV2.
+func (s *PerOperationSampler) OnFinishSpan(span *Span) SamplingDecision {
+ return SamplingDecision{Sample: false, Retryable: true}
+}
+
+func (s *PerOperationSampler) getSamplerForOperation(operation string) Sampler {
+ s.RLock()
+ sampler, ok := s.samplers[operation]
+ if ok {
+ defer s.RUnlock()
+ return sampler
+ }
+ s.RUnlock()
+ s.Lock()
+ defer s.Unlock()
+
+ // Check if sampler has already been created
+ sampler, ok = s.samplers[operation]
+ if ok {
+ return sampler
+ }
+ // Store only up to maxOperations of unique ops.
+ if len(s.samplers) >= s.maxOperations {
+ return s.defaultSampler
+ }
+ newSampler := newGuaranteedThroughputProbabilisticSampler(s.lowerBound, s.defaultSampler.SamplingRate())
+ s.samplers[operation] = newSampler
+ return newSampler
+}
+
+// Close invokes Close on all underlying samplers.
+func (s *PerOperationSampler) Close() {
+ s.Lock()
+ defer s.Unlock()
+ for _, sampler := range s.samplers {
+ sampler.Close()
+ }
+ s.defaultSampler.Close()
+}
+
+func (s *PerOperationSampler) String() string {
+ var sb strings.Builder
+
+ fmt.Fprintf(&sb, "PerOperationSampler(defaultSampler=%v, ", s.defaultSampler)
+ fmt.Fprintf(&sb, "lowerBound=%f, ", s.lowerBound)
+ fmt.Fprintf(&sb, "maxOperations=%d, ", s.maxOperations)
+ fmt.Fprintf(&sb, "operationNameLateBinding=%t, ", s.operationNameLateBinding)
+ fmt.Fprintf(&sb, "numOperations=%d,\n", len(s.samplers))
+ fmt.Fprintf(&sb, "samplers=[")
+ for operationName, sampler := range s.samplers {
+ fmt.Fprintf(&sb, "\n(operationName=%s, sampler=%v)", operationName, sampler)
+ }
+ fmt.Fprintf(&sb, "])")
+
+ return sb.String()
+}
+
+// Equal is not used.
+// TODO (breaking change) remove this in the future
+func (s *PerOperationSampler) Equal(other Sampler) bool {
+ // NB The Equal() function is overly expensive for PerOperationSampler since it's composed of multiple
+ // samplers which all need to be initialized before this function can be called for a comparison.
+ // Therefore, PerOperationSampler uses the update() function to only alter the samplers that need
+ // changing. Hence this function always returns false so that the update function can be called.
+ // Once the Equal() function is removed from the Sampler API, this will no longer be needed.
+ return false
+}
+
+func (s *PerOperationSampler) update(strategies *sampling.PerOperationSamplingStrategies) {
+ s.Lock()
+ defer s.Unlock()
+ newSamplers := map[string]*GuaranteedThroughputProbabilisticSampler{}
+ for _, strategy := range strategies.PerOperationStrategies {
+ operation := strategy.Operation
+ samplingRate := strategy.ProbabilisticSampling.SamplingRate
+ lowerBound := strategies.DefaultLowerBoundTracesPerSecond
+ if sampler, ok := s.samplers[operation]; ok {
+ sampler.update(lowerBound, samplingRate)
+ newSamplers[operation] = sampler
+ } else {
+ sampler := newGuaranteedThroughputProbabilisticSampler(
+ lowerBound,
+ samplingRate,
+ )
+ newSamplers[operation] = sampler
+ }
+ }
+ s.lowerBound = strategies.DefaultLowerBoundTracesPerSecond
+ if s.defaultSampler.SamplingRate() != strategies.DefaultSamplingProbability {
+ s.defaultSampler = newProbabilisticSampler(strategies.DefaultSamplingProbability)
+ }
+ s.samplers = newSamplers
+}