meter

README

metrics

The metrics package provides a simple metrics "Reporter" interface which allows the user to submit counters, gauges and timings (along with key/value tags).

Implementations

• Prometheus (pull): will be first
• Prometheus (push): certainly achievable
• InfluxDB: could quite easily be done
• Telegraf: almost identical to the InfluxDB implementation
• Micro: Could we provide metrics over Micro's server interface?

Todo

• Include a handler middleware which uses the Reporter interface to generate per-request level metrics
  • Throughput
  • Errors
  • Duration

Documentation

Overview

Package meter is for instrumentation

Index

• Variables
• type Counter
• type FloatCounter
• type Gauge
• type Histogram
• type Meter
  • func NewMeter(opts ...Option) Meter
• type Option
  • func Address(value string) Option
  • func Context(ctx context.Context) Option
  • func Logger(l logger.Logger) Option
  • func Metadata(md metadata.Metadata) Option
  • func Path(value string) Option
• type Options
  • func NewOptions(opt ...Option) Options
• type Summary

Variables

var (
	// The Meter data will be made available on this port
	DefaultAddress = ":9090"
	// This is the endpoint where the Meter data will be made available ("/metrics" is the default)
	DefaultPath = "/metrics"
)

Types

type Counter

type Counter interface {
	Add(int)
	Dec()
	Get() uint64
	Inc()
	Set(uint64)
}

Counter is a counter

type FloatCounter

type FloatCounter interface {
	Add(float64)
	Get() float64
	Set(float64)
	Sub(float64)
}

FloatCounter is a float64 counter

type Gauge

type Gauge interface {
	Get() float64
}

Gauge is a float64 gauge

type Histogram

type Histogram interface {
	Reset()
	Update(float64)
	UpdateDuration(time.Time)
}

Histogram is a histogram for non-negative values with automatically created buckets

type Meter

type Meter interface {
	Init(...Option) error
	Counter(string, metadata.Metadata) Counter
	FloatCounter(string, metadata.Metadata) FloatCounter
	Gauge(string, func() float64, metadata.Metadata) Gauge
	Set(metadata.Metadata) Meter
	Histogram(string, metadata.Metadata) Histogram
	Summary(string, metadata.Metadata) Summary
	SummaryExt(string, time.Duration, []float64, metadata.Metadata) Summary
	Options() Options
	String() string
}

Meter is an interface for collecting and instrumenting metrics

var (
	DefaultReporter Meter = NewMeter()
)

func NewMeter

func NewMeter(opts ...Option) Meter

NewMeter returns a configured noop reporter:

type Option

type Option func(*Options)

Option powers the configuration for metrics implementations:

func Address

func Address(value string) Option

Address is the listen address to serve metrics

func Context

func Context(ctx context.Context) Option

Cntext sets the metrics context

func Logger

func Logger(l logger.Logger) Option

Logger sets the logger

func Metadata

func Metadata(md metadata.Metadata) Option

Metadata will be added to every metric

func Path

func Path(value string) Option

Path used to serve metrics over HTTP

type Options

type Options struct {
	Address  string
	Path     string
	Metadata metadata.Metadata
	//TimingObjectives map[float64]float64
	Logger  logger.Logger
	Context context.Context
}

Options for metrics implementations:

func NewOptions

func NewOptions(opt ...Option) Options

NewOptions prepares a set of options:

type Summary

type Summary interface {
	Update(float64)
	UpdateDuration(time.Time)
}

Summary is the summary