propagation

Documentation

Overview

Package propagation manages propagation of trace context headers.

Index

• type Extractor
  • func (e Extractor) Extract(events ...interface{}) (*TraceContext, error)
  • func (e Extractor) ExtractFromLayer(hdr http.Header) *TraceContextExtended
  • func (e Extractor) InjectToLayer(tc *TraceContext, hdr http.Header)
• type TraceContext
• type TraceContextExtended

Types

type Extractor

type Extractor struct {
	// contains filtered or unexported fields
}

Extractor inserts trace context into and extracts trace context out of different types.

func (Extractor) Extract

func (e Extractor) Extract(events ...interface{}) (*TraceContext, error)

Extract looks in the given events one by one and returns once a proper trace context is found.

func (Extractor) ExtractFromLayer

func (e Extractor) ExtractFromLayer(hdr http.Header) *TraceContextExtended

ExtractFromLayer is used for extracting context from the request headers sent from a tracing layer. Currently, only datadog style headers are extracted. If a trace id or parent id are not found, then the embedded *TraceContext will be nil.

func (Extractor) InjectToLayer

func (e Extractor) InjectToLayer(tc *TraceContext, hdr http.Header)

InjectToLayer is used for injecting context into the response headers sent to a tracing layer. Currently, only datadog style headers are injected.

type TraceContext

type TraceContext struct {
	TraceID           uint64
	TraceIDUpper64Hex string
	ParentID          uint64
	SamplingPriority  sampler.SamplingPriority
}

TraceContext stores the propagated trace context values.

type TraceContextExtended

type TraceContextExtended struct {
	*TraceContext
	SpanID          uint64
	InvocationError bool
}

TraceContextExtended stores the propagated trace context values plus other non-standard header values.