pkg/health/health.go

// -------------------------------------------------------------------------------------------
// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License. See License.txt in the project root for license information.
// --------------------------------------------------------------------------------------------

package health

import "net/http"

// Probe is a type alias for a function.
type Probe func() bool

// Probes is the interface for liveness and readiness probes
type Probes interface {
	Liveness() bool
	Readiness() bool
}

func makeHandler(probe Probe) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
		w.WriteHeader(map[bool]int{
			true:  http.StatusOK,
			false: http.StatusServiceUnavailable,
		}[probe()])
	})
}

// ReadinessHandler returns readiness http handlers for health
func ReadinessHandler(probe Probes) http.Handler {
	return makeHandler(probe.Readiness)
}

// LivenessHandler returns readiness http handlers for health
func LivenessHandler(probe Probes) http.Handler {
	return makeHandler(probe.Liveness)
}