diff options
Diffstat (limited to 'vendor/github.com/uber/jaeger-client-go/tracer.go')
| -rw-r--r-- | vendor/github.com/uber/jaeger-client-go/tracer.go | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/vendor/github.com/uber/jaeger-client-go/tracer.go b/vendor/github.com/uber/jaeger-client-go/tracer.go new file mode 100644 index 000000000..198c32eb4 --- /dev/null +++ b/vendor/github.com/uber/jaeger-client-go/tracer.go @@ -0,0 +1,431 @@ +// Copyright (c) 2017-2018 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" + "io" + "os" + "reflect" + "strconv" + "sync" + "time" + + "github.com/opentracing/opentracing-go" + "github.com/opentracing/opentracing-go/ext" + + "github.com/uber/jaeger-client-go/internal/baggage" + "github.com/uber/jaeger-client-go/internal/throttler" + "github.com/uber/jaeger-client-go/log" + "github.com/uber/jaeger-client-go/utils" +) + +// Tracer implements opentracing.Tracer. +type Tracer struct { + serviceName string + hostIPv4 uint32 // this is for zipkin endpoint conversion + + sampler Sampler + reporter Reporter + metrics Metrics + logger log.Logger + + timeNow func() time.Time + randomNumber func() uint64 + + options struct { + poolSpans bool + gen128Bit bool // whether to generate 128bit trace IDs + zipkinSharedRPCSpan bool + highTraceIDGenerator func() uint64 // custom high trace ID generator + maxTagValueLength int + // more options to come + } + // pool for Span objects + spanPool sync.Pool + + injectors map[interface{}]Injector + extractors map[interface{}]Extractor + + observer compositeObserver + + tags []Tag + process Process + + baggageRestrictionManager baggage.RestrictionManager + baggageSetter *baggageSetter + + debugThrottler throttler.Throttler +} + +// NewTracer creates Tracer implementation that reports tracing to Jaeger. +// The returned io.Closer can be used in shutdown hooks to ensure that the internal +// queue of the Reporter is drained and all buffered spans are submitted to collectors. +func NewTracer( + serviceName string, + sampler Sampler, + reporter Reporter, + options ...TracerOption, +) (opentracing.Tracer, io.Closer) { + t := &Tracer{ + serviceName: serviceName, + sampler: sampler, + reporter: reporter, + injectors: make(map[interface{}]Injector), + extractors: make(map[interface{}]Extractor), + metrics: *NewNullMetrics(), + spanPool: sync.Pool{New: func() interface{} { + return &Span{} + }}, + } + + for _, option := range options { + option(t) + } + + // register default injectors/extractors unless they are already provided via options + textPropagator := newTextMapPropagator(getDefaultHeadersConfig(), t.metrics) + t.addCodec(opentracing.TextMap, textPropagator, textPropagator) + + httpHeaderPropagator := newHTTPHeaderPropagator(getDefaultHeadersConfig(), t.metrics) + t.addCodec(opentracing.HTTPHeaders, httpHeaderPropagator, httpHeaderPropagator) + + binaryPropagator := newBinaryPropagator(t) + t.addCodec(opentracing.Binary, binaryPropagator, binaryPropagator) + + // TODO remove after TChannel supports OpenTracing + interopPropagator := &jaegerTraceContextPropagator{tracer: t} + t.addCodec(SpanContextFormat, interopPropagator, interopPropagator) + + zipkinPropagator := &zipkinPropagator{tracer: t} + t.addCodec(ZipkinSpanFormat, zipkinPropagator, zipkinPropagator) + + if t.baggageRestrictionManager != nil { + t.baggageSetter = newBaggageSetter(t.baggageRestrictionManager, &t.metrics) + } else { + t.baggageSetter = newBaggageSetter(baggage.NewDefaultRestrictionManager(0), &t.metrics) + } + if t.debugThrottler == nil { + t.debugThrottler = throttler.DefaultThrottler{} + } + + if t.randomNumber == nil { + rng := utils.NewRand(time.Now().UnixNano()) + t.randomNumber = func() uint64 { + return uint64(rng.Int63()) + } + } + if t.timeNow == nil { + t.timeNow = time.Now + } + if t.logger == nil { + t.logger = log.NullLogger + } + // Set tracer-level tags + t.tags = append(t.tags, Tag{key: JaegerClientVersionTagKey, value: JaegerClientVersion}) + if hostname, err := os.Hostname(); err == nil { + t.tags = append(t.tags, Tag{key: TracerHostnameTagKey, value: hostname}) + } + if ip, err := utils.HostIP(); err == nil { + t.tags = append(t.tags, Tag{key: TracerIPTagKey, value: ip.String()}) + t.hostIPv4 = utils.PackIPAsUint32(ip) + } else { + t.logger.Error("Unable to determine this host's IP address: " + err.Error()) + } + + if t.options.gen128Bit { + if t.options.highTraceIDGenerator == nil { + t.options.highTraceIDGenerator = t.randomNumber + } + } else if t.options.highTraceIDGenerator != nil { + t.logger.Error("Overriding high trace ID generator but not generating " + + "128 bit trace IDs, consider enabling the \"Gen128Bit\" option") + } + if t.options.maxTagValueLength == 0 { + t.options.maxTagValueLength = DefaultMaxTagValueLength + } + t.process = Process{ + Service: serviceName, + UUID: strconv.FormatUint(t.randomNumber(), 16), + Tags: t.tags, + } + if throttler, ok := t.debugThrottler.(ProcessSetter); ok { + throttler.SetProcess(t.process) + } + + return t, t +} + +// addCodec adds registers injector and extractor for given propagation format if not already defined. +func (t *Tracer) addCodec(format interface{}, injector Injector, extractor Extractor) { + if _, ok := t.injectors[format]; !ok { + t.injectors[format] = injector + } + if _, ok := t.extractors[format]; !ok { + t.extractors[format] = extractor + } +} + +// StartSpan implements StartSpan() method of opentracing.Tracer. +func (t *Tracer) StartSpan( + operationName string, + options ...opentracing.StartSpanOption, +) opentracing.Span { + sso := opentracing.StartSpanOptions{} + for _, o := range options { + o.Apply(&sso) + } + return t.startSpanWithOptions(operationName, sso) +} + +func (t *Tracer) startSpanWithOptions( + operationName string, + options opentracing.StartSpanOptions, +) opentracing.Span { + if options.StartTime.IsZero() { + options.StartTime = t.timeNow() + } + + // Predicate whether the given span context is a valid reference + // which may be used as parent / debug ID / baggage items source + isValidReference := func(ctx SpanContext) bool { + return ctx.IsValid() || ctx.isDebugIDContainerOnly() || len(ctx.baggage) != 0 + } + + var references []Reference + var parent SpanContext + var hasParent bool // need this because `parent` is a value, not reference + for _, ref := range options.References { + ctx, ok := ref.ReferencedContext.(SpanContext) + if !ok { + t.logger.Error(fmt.Sprintf( + "Reference contains invalid type of SpanReference: %s", + reflect.ValueOf(ref.ReferencedContext))) + continue + } + if !isValidReference(ctx) { + continue + } + references = append(references, Reference{Type: ref.Type, Context: ctx}) + if !hasParent { + parent = ctx + hasParent = ref.Type == opentracing.ChildOfRef + } + } + if !hasParent && isValidReference(parent) { + // If ChildOfRef wasn't found but a FollowFromRef exists, use the context from + // the FollowFromRef as the parent + hasParent = true + } + + rpcServer := false + if v, ok := options.Tags[ext.SpanKindRPCServer.Key]; ok { + rpcServer = (v == ext.SpanKindRPCServerEnum || v == string(ext.SpanKindRPCServerEnum)) + } + + var samplerTags []Tag + var ctx SpanContext + newTrace := false + if !hasParent || !parent.IsValid() { + newTrace = true + ctx.traceID.Low = t.randomID() + if t.options.gen128Bit { + ctx.traceID.High = t.options.highTraceIDGenerator() + } + ctx.spanID = SpanID(ctx.traceID.Low) + ctx.parentID = 0 + ctx.flags = byte(0) + if hasParent && parent.isDebugIDContainerOnly() && t.isDebugAllowed(operationName) { + ctx.flags |= (flagSampled | flagDebug) + samplerTags = []Tag{{key: JaegerDebugHeader, value: parent.debugID}} + } else if sampled, tags := t.sampler.IsSampled(ctx.traceID, operationName); sampled { + ctx.flags |= flagSampled + samplerTags = tags + } + } else { + ctx.traceID = parent.traceID + if rpcServer && t.options.zipkinSharedRPCSpan { + // Support Zipkin's one-span-per-RPC model + ctx.spanID = parent.spanID + ctx.parentID = parent.parentID + } else { + ctx.spanID = SpanID(t.randomID()) + ctx.parentID = parent.spanID + } + ctx.flags = parent.flags + } + if hasParent { + // copy baggage items + if l := len(parent.baggage); l > 0 { + ctx.baggage = make(map[string]string, len(parent.baggage)) + for k, v := range parent.baggage { + ctx.baggage[k] = v + } + } + } + + sp := t.newSpan() + sp.context = ctx + sp.observer = t.observer.OnStartSpan(sp, operationName, options) + return t.startSpanInternal( + sp, + operationName, + options.StartTime, + samplerTags, + options.Tags, + newTrace, + rpcServer, + references, + ) +} + +// Inject implements Inject() method of opentracing.Tracer +func (t *Tracer) Inject(ctx opentracing.SpanContext, format interface{}, carrier interface{}) error { + c, ok := ctx.(SpanContext) + if !ok { + return opentracing.ErrInvalidSpanContext + } + if injector, ok := t.injectors[format]; ok { + return injector.Inject(c, carrier) + } + return opentracing.ErrUnsupportedFormat +} + +// Extract implements Extract() method of opentracing.Tracer +func (t *Tracer) Extract( + format interface{}, + carrier interface{}, +) (opentracing.SpanContext, error) { + if extractor, ok := t.extractors[format]; ok { + return extractor.Extract(carrier) + } + return nil, opentracing.ErrUnsupportedFormat +} + +// Close releases all resources used by the Tracer and flushes any remaining buffered spans. +func (t *Tracer) Close() error { + t.reporter.Close() + t.sampler.Close() + if mgr, ok := t.baggageRestrictionManager.(io.Closer); ok { + mgr.Close() + } + if throttler, ok := t.debugThrottler.(io.Closer); ok { + throttler.Close() + } + return nil +} + +// Tags returns a slice of tracer-level tags. +func (t *Tracer) Tags() []opentracing.Tag { + tags := make([]opentracing.Tag, len(t.tags)) + for i, tag := range t.tags { + tags[i] = opentracing.Tag{Key: tag.key, Value: tag.value} + } + return tags +} + +// newSpan returns an instance of a clean Span object. +// If options.PoolSpans is true, the spans are retrieved from an object pool. +func (t *Tracer) newSpan() *Span { + if !t.options.poolSpans { + return &Span{} + } + sp := t.spanPool.Get().(*Span) + sp.context = emptyContext + sp.tracer = nil + sp.tags = nil + sp.logs = nil + return sp +} + +func (t *Tracer) startSpanInternal( + sp *Span, + operationName string, + startTime time.Time, + internalTags []Tag, + tags opentracing.Tags, + newTrace bool, + rpcServer bool, + references []Reference, +) *Span { + sp.tracer = t + sp.operationName = operationName + sp.startTime = startTime + sp.duration = 0 + sp.references = references + sp.firstInProcess = rpcServer || sp.context.parentID == 0 + if len(tags) > 0 || len(internalTags) > 0 { + sp.tags = make([]Tag, len(internalTags), len(tags)+len(internalTags)) + copy(sp.tags, internalTags) + for k, v := range tags { + sp.observer.OnSetTag(k, v) + if k == string(ext.SamplingPriority) && !setSamplingPriority(sp, v) { + continue + } + sp.setTagNoLocking(k, v) + } + } + // emit metrics + if sp.context.IsSampled() { + t.metrics.SpansStartedSampled.Inc(1) + if newTrace { + // We cannot simply check for parentID==0 because in Zipkin model the + // server-side RPC span has the exact same trace/span/parent IDs as the + // calling client-side span, but obviously the server side span is + // no longer a root span of the trace. + t.metrics.TracesStartedSampled.Inc(1) + } else if sp.firstInProcess { + t.metrics.TracesJoinedSampled.Inc(1) + } + } else { + t.metrics.SpansStartedNotSampled.Inc(1) + if newTrace { + t.metrics.TracesStartedNotSampled.Inc(1) + } else if sp.firstInProcess { + t.metrics.TracesJoinedNotSampled.Inc(1) + } + } + return sp +} + +func (t *Tracer) reportSpan(sp *Span) { + t.metrics.SpansFinished.Inc(1) + if sp.context.IsSampled() { + t.reporter.Report(sp) + } + if t.options.poolSpans { + t.spanPool.Put(sp) + } +} + +// randomID generates a random trace/span ID, using tracer.random() generator. +// It never returns 0. +func (t *Tracer) randomID() uint64 { + val := t.randomNumber() + for val == 0 { + val = t.randomNumber() + } + return val +} + +// (NB) span must hold the lock before making this call +func (t *Tracer) setBaggage(sp *Span, key, value string) { + t.baggageSetter.setBaggage(sp, key, value) +} + +// (NB) span must hold the lock before making this call +func (t *Tracer) isDebugAllowed(operation string) bool { + return t.debugThrottler.IsAllowed(operation) +} |