tracing

Documentation

Index

• func InitJaeger(app string) error
• type Tracer
  • func NewTracer(pkgName, componentName string) Tracer

Functions

func InitJaeger

func InitJaeger(app string) error

InitJaeger asserts that the global tracer is initialized.

This will read the configuration from the "JAEGER_*"" environment variables. Overriding the empty values with the supplied app value. If a sampler type is not configured via the environment variables, then InitJaeger will be configured with the constant sampler.

Types

type Tracer

type Tracer interface {
	StartSpan(ctx context.Context, operationName string) (opentracing.Span, context.Context)
	FinishSpan(opentracing.Span, error)
}

Tracer contains all the tracing-related functions for any module of the server that uses tracing

Normally, if you have a module that needs tracing you embed the Tracer as following:

type Some struct {
  tracing.Tracer
}

And then initialize the tracer when you initialize the module:

func NewSome() Some {
  return Some{
    Tracer: tracing.NewTracer("package", "Some"),
  }
}

To use the tracing capabilities you use it as following:

func (s Some) Foo(ctx context.Context) (err error) {
  span, ctx := s.StartSpan(ctx, "Foo")
  // since the err is not assigned yet we have to take it into the closure
  defer func() {
    s.FinishSpan(span, err)
  }()
  span.SetTag("something", "important")
  ...
}

func NewTracer

func NewTracer(pkgName, componentName string) Tracer

NewTracer create a new tracer that contains implementation for all tracing-related actions