trace

Documentation

Overview

Package trace abstracts virtual-kubelet's tracing capabilties into a set of interfaces. While this does allow consumers to use whatever tracing library they want, the primary goal is to share logging data between the configured logger and tracing spans instead of duplicating calls.

Index

• type Span
  • func StartSpan(ctx context.Context, name string) (context.Context, Span)
• type Tracer

Types

type Span

type Span interface {
	End()

	// SetStatus sets the final status of the span.
	// errors passed to this should use interfaces defined in
	// github.com/virtual-kubelet/virtual-kubelet/errdefs
	//
	// If the error is nil, the span should be considered successful.
	SetStatus(err error)

	// WithField and WithFields adds attributes to an entire span
	//
	// This interface is a bit weird, but allows us to manage loggers in the context
	// It is expected that implementations set `log.WithLogger` so the logger stored
	// in the context is updated with the new fields.
	WithField(context.Context, string, interface{}) context.Context
	WithFields(context.Context, log.Fields) context.Context

	// Logger is used to log individual entries.
	// Calls to functions like `WithField` and `WithFields` on the logger should
	// not affect the rest of the span but rather individual entries.
	Logger() log.Logger
}

Span encapsulates a tracing event

func StartSpan

func StartSpan(ctx context.Context, name string) (context.Context, Span)

StartSpan starts a span from the configured default tracer

type Tracer

type Tracer interface {
	// StartSpan starts a new span. The span details are emebedded into the returned
	// context
	StartSpan(context.Context, string) (context.Context, Span)
}

Tracer is the interface used for creating a tracing span

var (
	// T is the Tracer to use this should be initialized before starting up
	// virtual-kubelet
	T Tracer = nopTracer{}
)