health

Documentation

Overview

Copyright 2020 The UnDistro authors

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Index

• func HandleLive(w http.ResponseWriter, _ *http.Request)
• type Checker
• type CheckerFunc
  • func (f CheckerFunc) CheckHealth() error
• type Handler
  • func (h *Handler) Add(c Checker)
  • func (h *Handler) ServeHTTP(w http.ResponseWriter, _ *http.Request)

Functions

func HandleLive

func HandleLive(w http.ResponseWriter, _ *http.Request)

HandleLive is an http.HandlerFunc that handles liveness checks by immediately responding with an HTTP 200 status.

Types

type Checker

type Checker interface {
	CheckHealth() error
}

Checker wraps the CheckHealth method.

CheckHealth returns nil if the resource is healthy, or a non-nil error if the resource is not healthy. CheckHealth must be safe to call from multiple goroutines.

type CheckerFunc

type CheckerFunc func() error

CheckerFunc is an adapter type to allow the use of ordinary functions as health checks. If f is a function with the appropriate signature, CheckerFunc(f) is a Checker that calls f.

func (CheckerFunc) CheckHealth

func (f CheckerFunc) CheckHealth() error

CheckHealth calls f().

type Handler

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

Handler is an HTTP handler that reports on the success of an aggregate of Checkers. The zero value is always healthy.

func (*Handler) Add

func (h *Handler) Add(c Checker)

Add adds a new check to the handler.

func (*Handler) ServeHTTP

func (h *Handler) ServeHTTP(w http.ResponseWriter, _ *http.Request)

ServeHTTP returns 200 if it is healthy, 500 otherwise.