metrics

Documentation

Overview

Package metrics provides a unified interface for different metrics backends (prometheus etc.).

Index

• Variables
• func Active() bool
• func CtxGetScope(ctx context.Context) string
• func CtxScope(ctx context.Context, scope string) context.Context
• func CtxSubScope(ctx context.Context, subscope string) context.Context
• func InjectImpl(newimpl InternalNew) error
• type Counter
• type CounterVec
• type Creator
  • func New(name, helptext string) Creator
  • func NewCtx(ctx context.Context, name, helptext string) Creator
• type Gauge
• type Histogram
• type InternalNew
• type Summary
• type SummaryOpts

Variables

var CtxScopeKey = ctxScopeKey{}

var ErrImplemented = errors.New("there is implemenation already injected")

Functions

func Active

func Active() bool

func CtxGetScope

func CtxGetScope(ctx context.Context) string

func CtxScope

func CtxScope(ctx context.Context, scope string) context.Context

func CtxSubScope

func CtxSubScope(ctx context.Context, subscope string) context.Context

func InjectImpl

func InjectImpl(newimpl InternalNew) error

Types

type Counter

type Counter interface {
	Inc()
	Add(float64) // Only positive
}

Counter is a metric that can only be incremented.

type CounterVec

type CounterVec interface {
	WithLabelValues(lvs ...string) Counter
}

CounterVec is a counter with tags.

type Creator

type Creator interface {
	Counter() Counter
	CounterVec(labelNames []string) CounterVec
	Gauge() Gauge
	Histogram(buckets []float64) Histogram

	// opts cannot be nil, use empty summary instance
	Summary(opts SummaryOpts) Summary
}

Creator can be used to create different types of metrics.

func New

func New(name, helptext string) Creator

New returns a Creator. Name is a dot separated path which must be unique. Examples: ipfs.blockstore.bloomcache.bloom.miss.total ipfs.routing.dht.notresuingstream.total

Both arguemnts are mandatory.

func NewCtx

func NewCtx(ctx context.Context, name, helptext string) Creator

NewCtx is like New but obtains the metric scope from the given context.

type Gauge

type Gauge interface {
	Set(float64) // Introduced discontinuity
	Inc()
	Dec()
	Add(float64)
	Sub(float64)
}

Gauge is a metric that can be increased and decreased.

type Histogram

type Histogram interface {
	Observe(float64) // Adds observation to Histogram
}

Histogram metric.

type InternalNew

type InternalNew func(string, string) Creator

type Summary

type Summary interface {
	Observe(float64) // Adds observation to Summary
}

type SummaryOpts

type SummaryOpts struct {
	Objectives map[float64]float64
	MaxAge     time.Duration
	AgeBuckets uint32
	BufCap     uint32
}

SummaryOpts allow specifying options for Summary. See: http://godoc.org/github.com/prometheus/client_golang/prometheus#SummaryOpts .