zipper

Documentation

Overview

Package zipper exposes following non-monitoring endpoints:

• /metrics/find
• /render
• /info

Error codes policy (applies to find, render, info endpoints)

• if at least one backend succeeds, it's a success with code 200.
• if all bakends fail
• if all errors are not-found, it's a not found. But code is 200 + a monitoring counter incremented.
• if errors are of mixed type we fail with code 500.

Index

• Variables
• type App
  • func New(config cfg.Zipper, logger *zap.Logger, buildVersion string) (*App, error)
  • func (app *App) Start(logger *zap.Logger) func()
• type PrometheusMetrics
  • func NewPrometheusMetrics(config cfg.Zipper) *PrometheusMetrics

Variables

var BuildVersion string

BuildVersion is replaced by ldflags

var Metrics = struct {
	Requests  *expvar.Int
	Responses *expvar.Int
	Errors    *expvar.Int

	Goroutines expvar.Func
	Uptime     expvar.Func

	FindRequests *expvar.Int
	FindErrors   *expvar.Int

	RenderRequests *expvar.Int
	RenderErrors   *expvar.Int

	InfoRequests *expvar.Int
	InfoErrors   *expvar.Int

	Timeouts *expvar.Int

	CacheSize   expvar.Func
	CacheItems  expvar.Func
	CacheMisses *expvar.Int
	CacheHits   *expvar.Int
}{
	Requests:  expvar.NewInt("requests"),
	Responses: expvar.NewInt("responses"),
	Errors:    expvar.NewInt("errors"),

	FindRequests: expvar.NewInt("find_requests"),
	FindErrors:   expvar.NewInt("find_errors"),

	RenderRequests: expvar.NewInt("render_requests"),
	RenderErrors:   expvar.NewInt("render_errors"),

	InfoRequests: expvar.NewInt("info_requests"),
	InfoErrors:   expvar.NewInt("info_errors"),

	Timeouts: expvar.NewInt("timeouts"),

	CacheHits:   expvar.NewInt("cache_hits"),
	CacheMisses: expvar.NewInt("cache_misses"),
}

Metrics contains grouped expvars for /debug/vars and graphite

Types

type App

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

App represents the main zipper runnable

func New

func New(config cfg.Zipper, logger *zap.Logger, buildVersion string) (*App, error)

New inits backends and makes a new copy of the app. Does not run the app

func (*App) Start

func (app *App) Start(logger *zap.Logger) func()

Start start launches the goroutines starts the app execution

type PrometheusMetrics

type PrometheusMetrics struct {
	Requests                  prometheus.Counter
	Responses                 *prometheus.CounterVec
	RenderMismatches          prometheus.Counter
	RenderFixedMismatches     prometheus.Counter
	RenderMismatchedResponses prometheus.Counter
	Renders                   prometheus.Counter
	FindNotFound              prometheus.Counter
	RequestCancel             *prometheus.CounterVec
	DurationExp               prometheus.Histogram
	DurationLin               prometheus.Histogram
	RenderDurationExp         prometheus.Histogram
	RenderOutDurationExp      *prometheus.HistogramVec
	FindDurationExp           prometheus.Histogram
	FindDurationLin           prometheus.Histogram
	TimeInQueueExp            prometheus.Histogram
	TimeInQueueLin            prometheus.Histogram
}

PrometheusMetrics keeps all the metrics exposed on /metrics endpoint

func NewPrometheusMetrics

func NewPrometheusMetrics(config cfg.Zipper) *PrometheusMetrics

NewPrometheusMetrics creates a set of default Prom metrics