diff options
Diffstat (limited to 'vendor/go.opencensus.io/trace/trace.go')
-rw-r--r-- | vendor/go.opencensus.io/trace/trace.go | 187 |
1 files changed, 92 insertions, 95 deletions
diff --git a/vendor/go.opencensus.io/trace/trace.go b/vendor/go.opencensus.io/trace/trace.go index 3f8977b41..861df9d39 100644 --- a/vendor/go.opencensus.io/trace/trace.go +++ b/vendor/go.opencensus.io/trace/trace.go @@ -28,12 +28,16 @@ import ( "go.opencensus.io/trace/tracestate" ) +type tracer struct{} + +var _ Tracer = &tracer{} + // Span represents a span of a trace. It has an associated SpanContext, and // stores data accumulated while the span is active. // // Ideally users should interact with Spans by calling the functions in this // package that take a Context parameter. -type Span struct { +type span struct { // data contains information recorded about the span. // // It will be non-nil if we are exporting the span or recording events for it. @@ -66,7 +70,7 @@ type Span struct { // IsRecordingEvents returns true if events are being recorded for this span. // Use this check to avoid computing expensive annotations when they will never // be used. -func (s *Span) IsRecordingEvents() bool { +func (s *span) IsRecordingEvents() bool { if s == nil { return false } @@ -109,13 +113,13 @@ type SpanContext struct { type contextKey struct{} // FromContext returns the Span stored in a context, or nil if there isn't one. -func FromContext(ctx context.Context) *Span { +func (t *tracer) FromContext(ctx context.Context) *Span { s, _ := ctx.Value(contextKey{}).(*Span) return s } // NewContext returns a new context with the given Span attached. -func NewContext(parent context.Context, s *Span) context.Context { +func (t *tracer) NewContext(parent context.Context, s *Span) context.Context { return context.WithValue(parent, contextKey{}, s) } @@ -166,12 +170,14 @@ func WithSampler(sampler Sampler) StartOption { // // Returned context contains the newly created span. You can use it to // propagate the returned span in process. -func StartSpan(ctx context.Context, name string, o ...StartOption) (context.Context, *Span) { +func (t *tracer) StartSpan(ctx context.Context, name string, o ...StartOption) (context.Context, *Span) { var opts StartOptions var parent SpanContext - if p := FromContext(ctx); p != nil { - p.addChild() - parent = p.spanContext + if p := t.FromContext(ctx); p != nil { + if ps, ok := p.internal.(*span); ok { + ps.addChild() + } + parent = p.SpanContext() } for _, op := range o { op(&opts) @@ -180,7 +186,8 @@ func StartSpan(ctx context.Context, name string, o ...StartOption) (context.Cont ctx, end := startExecutionTracerTask(ctx, name) span.executionTracerTaskEnd = end - return NewContext(ctx, span), span + extSpan := NewSpan(span) + return t.NewContext(ctx, extSpan), extSpan } // StartSpanWithRemoteParent starts a new child span of the span from the given parent. @@ -190,7 +197,7 @@ func StartSpan(ctx context.Context, name string, o ...StartOption) (context.Cont // // Returned context contains the newly created span. You can use it to // propagate the returned span in process. -func StartSpanWithRemoteParent(ctx context.Context, name string, parent SpanContext, o ...StartOption) (context.Context, *Span) { +func (t *tracer) StartSpanWithRemoteParent(ctx context.Context, name string, parent SpanContext, o ...StartOption) (context.Context, *Span) { var opts StartOptions for _, op := range o { op(&opts) @@ -198,19 +205,24 @@ func StartSpanWithRemoteParent(ctx context.Context, name string, parent SpanCont span := startSpanInternal(name, parent != SpanContext{}, parent, true, opts) ctx, end := startExecutionTracerTask(ctx, name) span.executionTracerTaskEnd = end - return NewContext(ctx, span), span + extSpan := NewSpan(span) + return t.NewContext(ctx, extSpan), extSpan } -func startSpanInternal(name string, hasParent bool, parent SpanContext, remoteParent bool, o StartOptions) *Span { - span := &Span{} - span.spanContext = parent +func startSpanInternal(name string, hasParent bool, parent SpanContext, remoteParent bool, o StartOptions) *span { + s := &span{} + s.spanContext = parent cfg := config.Load().(*Config) + if gen, ok := cfg.IDGenerator.(*defaultIDGenerator); ok { + // lazy initialization + gen.init() + } if !hasParent { - span.spanContext.TraceID = cfg.IDGenerator.NewTraceID() + s.spanContext.TraceID = cfg.IDGenerator.NewTraceID() } - span.spanContext.SpanID = cfg.IDGenerator.NewSpanID() + s.spanContext.SpanID = cfg.IDGenerator.NewSpanID() sampler := cfg.DefaultSampler if !hasParent || remoteParent || o.Sampler != nil { @@ -222,47 +234,47 @@ func startSpanInternal(name string, hasParent bool, parent SpanContext, remotePa if o.Sampler != nil { sampler = o.Sampler } - span.spanContext.setIsSampled(sampler(SamplingParameters{ + s.spanContext.setIsSampled(sampler(SamplingParameters{ ParentContext: parent, - TraceID: span.spanContext.TraceID, - SpanID: span.spanContext.SpanID, + TraceID: s.spanContext.TraceID, + SpanID: s.spanContext.SpanID, Name: name, HasRemoteParent: remoteParent}).Sample) } - if !internal.LocalSpanStoreEnabled && !span.spanContext.IsSampled() { - return span + if !internal.LocalSpanStoreEnabled && !s.spanContext.IsSampled() { + return s } - span.data = &SpanData{ - SpanContext: span.spanContext, + s.data = &SpanData{ + SpanContext: s.spanContext, StartTime: time.Now(), SpanKind: o.SpanKind, Name: name, HasRemoteParent: remoteParent, } - span.lruAttributes = newLruMap(cfg.MaxAttributesPerSpan) - span.annotations = newEvictedQueue(cfg.MaxAnnotationEventsPerSpan) - span.messageEvents = newEvictedQueue(cfg.MaxMessageEventsPerSpan) - span.links = newEvictedQueue(cfg.MaxLinksPerSpan) + s.lruAttributes = newLruMap(cfg.MaxAttributesPerSpan) + s.annotations = newEvictedQueue(cfg.MaxAnnotationEventsPerSpan) + s.messageEvents = newEvictedQueue(cfg.MaxMessageEventsPerSpan) + s.links = newEvictedQueue(cfg.MaxLinksPerSpan) if hasParent { - span.data.ParentSpanID = parent.SpanID + s.data.ParentSpanID = parent.SpanID } if internal.LocalSpanStoreEnabled { var ss *spanStore ss = spanStoreForNameCreateIfNew(name) if ss != nil { - span.spanStore = ss - ss.add(span) + s.spanStore = ss + ss.add(s) } } - return span + return s } // End ends the span. -func (s *Span) End() { +func (s *span) End() { if s == nil { return } @@ -292,7 +304,7 @@ func (s *Span) End() { // makeSpanData produces a SpanData representing the current state of the Span. // It requires that s.data is non-nil. -func (s *Span) makeSpanData() *SpanData { +func (s *span) makeSpanData() *SpanData { var sd SpanData s.mu.Lock() sd = *s.data @@ -317,7 +329,7 @@ func (s *Span) makeSpanData() *SpanData { } // SpanContext returns the SpanContext of the span. -func (s *Span) SpanContext() SpanContext { +func (s *span) SpanContext() SpanContext { if s == nil { return SpanContext{} } @@ -325,7 +337,7 @@ func (s *Span) SpanContext() SpanContext { } // SetName sets the name of the span, if it is recording events. -func (s *Span) SetName(name string) { +func (s *span) SetName(name string) { if !s.IsRecordingEvents() { return } @@ -335,7 +347,7 @@ func (s *Span) SetName(name string) { } // SetStatus sets the status of the span, if it is recording events. -func (s *Span) SetStatus(status Status) { +func (s *span) SetStatus(status Status) { if !s.IsRecordingEvents() { return } @@ -344,32 +356,32 @@ func (s *Span) SetStatus(status Status) { s.mu.Unlock() } -func (s *Span) interfaceArrayToLinksArray() []Link { - linksArr := make([]Link, 0) +func (s *span) interfaceArrayToLinksArray() []Link { + linksArr := make([]Link, 0, len(s.links.queue)) for _, value := range s.links.queue { linksArr = append(linksArr, value.(Link)) } return linksArr } -func (s *Span) interfaceArrayToMessageEventArray() []MessageEvent { - messageEventArr := make([]MessageEvent, 0) +func (s *span) interfaceArrayToMessageEventArray() []MessageEvent { + messageEventArr := make([]MessageEvent, 0, len(s.messageEvents.queue)) for _, value := range s.messageEvents.queue { messageEventArr = append(messageEventArr, value.(MessageEvent)) } return messageEventArr } -func (s *Span) interfaceArrayToAnnotationArray() []Annotation { - annotationArr := make([]Annotation, 0) +func (s *span) interfaceArrayToAnnotationArray() []Annotation { + annotationArr := make([]Annotation, 0, len(s.annotations.queue)) for _, value := range s.annotations.queue { annotationArr = append(annotationArr, value.(Annotation)) } return annotationArr } -func (s *Span) lruAttributesToAttributeMap() map[string]interface{} { - attributes := make(map[string]interface{}) +func (s *span) lruAttributesToAttributeMap() map[string]interface{} { + attributes := make(map[string]interface{}, s.lruAttributes.len()) for _, key := range s.lruAttributes.keys() { value, ok := s.lruAttributes.get(key) if ok { @@ -380,13 +392,13 @@ func (s *Span) lruAttributesToAttributeMap() map[string]interface{} { return attributes } -func (s *Span) copyToCappedAttributes(attributes []Attribute) { +func (s *span) copyToCappedAttributes(attributes []Attribute) { for _, a := range attributes { s.lruAttributes.add(a.key, a.value) } } -func (s *Span) addChild() { +func (s *span) addChild() { if !s.IsRecordingEvents() { return } @@ -398,7 +410,7 @@ func (s *Span) addChild() { // AddAttributes sets attributes in the span. // // Existing attributes whose keys appear in the attributes parameter are overwritten. -func (s *Span) AddAttributes(attributes ...Attribute) { +func (s *span) AddAttributes(attributes ...Attribute) { if !s.IsRecordingEvents() { return } @@ -407,49 +419,27 @@ func (s *Span) AddAttributes(attributes ...Attribute) { s.mu.Unlock() } -// copyAttributes copies a slice of Attributes into a map. -func copyAttributes(m map[string]interface{}, attributes []Attribute) { - for _, a := range attributes { - m[a.key] = a.value - } -} - -func (s *Span) lazyPrintfInternal(attributes []Attribute, format string, a ...interface{}) { +func (s *span) printStringInternal(attributes []Attribute, str string) { now := time.Now() - msg := fmt.Sprintf(format, a...) - var m map[string]interface{} - s.mu.Lock() + var am map[string]interface{} if len(attributes) != 0 { - m = make(map[string]interface{}) - copyAttributes(m, attributes) + am = make(map[string]interface{}, len(attributes)) + for _, attr := range attributes { + am[attr.key] = attr.value + } } - s.annotations.add(Annotation{ - Time: now, - Message: msg, - Attributes: m, - }) - s.mu.Unlock() -} - -func (s *Span) printStringInternal(attributes []Attribute, str string) { - now := time.Now() - var a map[string]interface{} s.mu.Lock() - if len(attributes) != 0 { - a = make(map[string]interface{}) - copyAttributes(a, attributes) - } s.annotations.add(Annotation{ Time: now, Message: str, - Attributes: a, + Attributes: am, }) s.mu.Unlock() } // Annotate adds an annotation with attributes. // Attributes can be nil. -func (s *Span) Annotate(attributes []Attribute, str string) { +func (s *span) Annotate(attributes []Attribute, str string) { if !s.IsRecordingEvents() { return } @@ -457,11 +447,11 @@ func (s *Span) Annotate(attributes []Attribute, str string) { } // Annotatef adds an annotation with attributes. -func (s *Span) Annotatef(attributes []Attribute, format string, a ...interface{}) { +func (s *span) Annotatef(attributes []Attribute, format string, a ...interface{}) { if !s.IsRecordingEvents() { return } - s.lazyPrintfInternal(attributes, format, a...) + s.printStringInternal(attributes, fmt.Sprintf(format, a...)) } // AddMessageSendEvent adds a message send event to the span. @@ -470,7 +460,7 @@ func (s *Span) Annotatef(attributes []Attribute, format string, a ...interface{} // unique in this span and the same between the send event and the receive // event (this allows to identify a message between the sender and receiver). // For example, this could be a sequence id. -func (s *Span) AddMessageSendEvent(messageID, uncompressedByteSize, compressedByteSize int64) { +func (s *span) AddMessageSendEvent(messageID, uncompressedByteSize, compressedByteSize int64) { if !s.IsRecordingEvents() { return } @@ -492,7 +482,7 @@ func (s *Span) AddMessageSendEvent(messageID, uncompressedByteSize, compressedBy // unique in this span and the same between the send event and the receive // event (this allows to identify a message between the sender and receiver). // For example, this could be a sequence id. -func (s *Span) AddMessageReceiveEvent(messageID, uncompressedByteSize, compressedByteSize int64) { +func (s *span) AddMessageReceiveEvent(messageID, uncompressedByteSize, compressedByteSize int64) { if !s.IsRecordingEvents() { return } @@ -509,7 +499,7 @@ func (s *Span) AddMessageReceiveEvent(messageID, uncompressedByteSize, compresse } // AddLink adds a link to the span. -func (s *Span) AddLink(l Link) { +func (s *span) AddLink(l Link) { if !s.IsRecordingEvents() { return } @@ -518,7 +508,7 @@ func (s *Span) AddLink(l Link) { s.mu.Unlock() } -func (s *Span) String() string { +func (s *span) String() string { if s == nil { return "<nil>" } @@ -534,20 +524,9 @@ func (s *Span) String() string { var config atomic.Value // access atomically func init() { - gen := &defaultIDGenerator{} - // initialize traceID and spanID generators. - var rngSeed int64 - for _, p := range []interface{}{ - &rngSeed, &gen.traceIDAdd, &gen.nextSpanID, &gen.spanIDInc, - } { - binary.Read(crand.Reader, binary.LittleEndian, p) - } - gen.traceIDRand = rand.New(rand.NewSource(rngSeed)) - gen.spanIDInc |= 1 - config.Store(&Config{ DefaultSampler: ProbabilitySampler(defaultSamplingProbability), - IDGenerator: gen, + IDGenerator: &defaultIDGenerator{}, MaxAttributesPerSpan: DefaultMaxAttributesPerSpan, MaxAnnotationEventsPerSpan: DefaultMaxAnnotationEventsPerSpan, MaxMessageEventsPerSpan: DefaultMaxMessageEventsPerSpan, @@ -571,6 +550,24 @@ type defaultIDGenerator struct { traceIDAdd [2]uint64 traceIDRand *rand.Rand + + initOnce sync.Once +} + +// init initializes the generator on the first call to avoid consuming entropy +// unnecessarily. +func (gen *defaultIDGenerator) init() { + gen.initOnce.Do(func() { + // initialize traceID and spanID generators. + var rngSeed int64 + for _, p := range []interface{}{ + &rngSeed, &gen.traceIDAdd, &gen.nextSpanID, &gen.spanIDInc, + } { + binary.Read(crand.Reader, binary.LittleEndian, p) + } + gen.traceIDRand = rand.New(rand.NewSource(rngSeed)) + gen.spanIDInc |= 1 + }) } // NewSpanID returns a non-zero span ID from a randomly-chosen sequence. |