tracing

func AnnotateTrace ¶

func AnnotateTrace()

AnnotateTrace adds an annotation to the golang executation tracer by calling a no-op cgo function.

func ChildSpan ¶

func ChildSpan(ctx context.Context, opName string) (context.Context, opentracing.Span)

ChildSpan opens a span as a child of the current span in the context (if there is one).

Returns the new context and the new span (if any). The span should be closed via FinishSpan.

func DecodeRawSpan ¶

func DecodeRawSpan(enc []byte, dest *basictracer.RawSpan) error

DecodeRawSpan unmarshals into the given RawSpan.

func Disable ¶

func Disable() func()

Disable is for benchmarking use and causes all future tracers to deal in no-ops. Calling the returned closure undoes this effect. There is no synchronization, so no moving parts are allowed while Disable and the closure are called.

func EncodeRawSpan ¶

func EncodeRawSpan(rawSpan *basictracer.RawSpan, dest []byte) ([]byte, error)

EncodeRawSpan encodes a raw span into bytes, using the given dest slice as a buffer.

func EnsureContext ¶

func EnsureContext(ctx context.Context, tracer opentracing.Tracer) (context.Context, func())

EnsureContext checks whether the given context.Context contains a Span. If not, it creates one using the provided Tracer and wraps it in the returned Span. The returned closure must be called after the request has been fully processed.

func FinishSpan ¶

func FinishSpan(span opentracing.Span)

FinishSpan closes the given span (if not nil). It is a convenience wrapper for span.Finish() which tolerates nil spans.

func ForkCtxSpan ¶

func ForkCtxSpan(ctx context.Context, opName string) (context.Context, opentracing.Span)

ForkCtxSpan checks if ctx has a Span open; if it does, it creates a new Span that follows from the original Span. This allows the resulting context to be used in an async task that might outlive the original operation.

Returns the new context and the new span (if any). The span should be closed via FinishSpan.

func FormatRawSpans ¶

func FormatRawSpans(spans []basictracer.RawSpan) string

FormatRawSpans formats the given spans for human consumption, showing the relationship using nesting and times as both relative to the previous event and cumulative.

func JoinOrNew ¶

func JoinOrNew(tr opentracing.Tracer, carrier *Span, opName string) (opentracing.Span, error)

JoinOrNew creates a new Span joined to the provided DelegatingCarrier or creates Span from the given tracer.

func JoinOrNewSnowball ¶

func JoinOrNewSnowball(
	opName string, carrier *Span, recorder func(sp basictracer.RawSpan),
) (opentracing.Span, error)

JoinOrNewSnowball returns a Span which records directly via the specified callback. If the given DelegatingCarrier is nil, a new Span is created. otherwise, the created Span is a child.

The recorder should be nil if we don't need to record spans.

TODO(andrei): JoinOrNewSnowball creates a new tracer, which is not kosher. Also this can't use the lightstep tracer.

func NewTeeTracer ¶

func NewTeeTracer(tracers ...opentracing.Tracer) opentracing.Tracer

NewTeeTracer creates a Tracer that sends events to multiple Tracers.

Note that only the span from the first tracer is used for serialization purposes (Inject/Extract).

func NewTracer ¶

func NewTracer() opentracing.Tracer

NewTracer creates a Tracer which records to the net/trace endpoint.

func NewTracerAndSpanFor7881 ¶

func NewTracerAndSpanFor7881(
	callback func(sp basictracer.RawSpan),
) (opentracing.Span, opentracing.Tracer, error)

NewTracerAndSpanFor7881 creates a new tracer and a root span. The tracer is to be used for tracking down #7881; it runs a callback for each finished span (and the callback used accumulates the spans in a SQL txn).

func TracerFromCtx ¶

func TracerFromCtx(ctx context.Context) opentracing.Tracer

TracerFromCtx returns the tracer set on the context (or a parent context) via WithTracer.

func WithTracer ¶

func WithTracer(ctx context.Context, tracer opentracing.Tracer) context.Context

WithTracer returns a context derived from the given context, for which TracerFromCtx returns the given tracer.