healthz

Documentation

Overview

Package healthz implements basic http server health checking. Usage:

import "k8s.io/apiserver/pkg/server/healthz"
healthz.InstallHandler(mux)

Index

• Constants
• func InstallHandler(mux mux, checks ...HealthChecker)
• func InstallLivezHandler(mux mux, checks ...HealthChecker)
• func InstallPathHandler(mux mux, path string, checks ...HealthChecker)
• func InstallPathHandlerWithHealthyFunc(mux mux, path string, firstTimeHealthy func(), checks ...HealthChecker)
• func InstallReadyzHandler(mux mux, checks ...HealthChecker)
• type HealthChecker
  • func NamedCheck(name string, check func(r *http.Request) error) HealthChecker
  • func NewInformerSyncHealthz(cacheSyncWaiter cacheSyncWaiter) HealthChecker
  • func NewShutdownHealthz(stopCh <-chan struct{}) HealthChecker

Constants

const DefaultHealthzPath = "/healthz"

Functions

func InstallHandler

func InstallHandler(mux mux, checks ...HealthChecker)

InstallHandler registers handlers for health checking on the path "/healthz" to mux. *All handlers* for mux must be specified in exactly one call to InstallHandler. Calling InstallHandler more than once for the same mux will result in a panic.

func InstallLivezHandler

func InstallLivezHandler(mux mux, checks ...HealthChecker)

InstallLivezHandler registers handlers for liveness checking on the path "/livez" to mux. *All handlers* for mux must be specified in exactly one call to InstallHandler. Calling InstallHandler more than once for the same mux will result in a panic.

func InstallPathHandler

func InstallPathHandler(mux mux, path string, checks ...HealthChecker)

InstallPathHandler registers handlers for health checking on a specific path to mux. *All handlers* for the path must be specified in exactly one call to InstallPathHandler. Calling InstallPathHandler more than once for the same path and mux will result in a panic.

func InstallPathHandlerWithHealthyFunc

func InstallPathHandlerWithHealthyFunc(mux mux, path string, firstTimeHealthy func(), checks ...HealthChecker)

InstallPathHandlerWithHealthyFunc is like InstallPathHandler, but calls firstTimeHealthy exactly once when the handler succeeds for the first time.

func InstallReadyzHandler

func InstallReadyzHandler(mux mux, checks ...HealthChecker)

InstallReadyzHandler registers handlers for health checking on the path "/readyz" to mux. *All handlers* for mux must be specified in exactly one call to InstallHandler. Calling InstallHandler more than once for the same mux will result in a panic.

Types

type HealthChecker

type HealthChecker interface {
	Name() string
	Check(req *http.Request) error
}

HealthChecker is a named healthz checker.

var LogHealthz HealthChecker = &log{}

LogHealthz returns true if logging is not blocked

var PingHealthz HealthChecker = ping{}

PingHealthz returns true automatically when checked

func NamedCheck

func NamedCheck(name string, check func(r *http.Request) error) HealthChecker

NamedCheck returns a healthz checker for the given name and function.

func NewInformerSyncHealthz

func NewInformerSyncHealthz(cacheSyncWaiter cacheSyncWaiter) HealthChecker

NewInformerSyncHealthz returns a new HealthChecker that will pass only if all informers in the given cacheSyncWaiter sync.

func NewShutdownHealthz

func NewShutdownHealthz(stopCh <-chan struct{}) HealthChecker

NewShutdownHealthz returns a new HealthChecker that will fail if the embedded channel is closed. This is intended to allow for graceful shutdown sequences.