tailscale/cmd/containerboot/healthz.go

52 lines
1.3 KiB
Go

// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause
//go:build linux
package main
import (
"log"
"net"
"net/http"
"sync"
)
// healthz is a simple health check server, if enabled it returns 200 OK if
// this tailscale node currently has at least one tailnet IP address else
// returns 503.
type healthz struct {
sync.Mutex
hasAddrs bool
}
func (h *healthz) ServeHTTP(w http.ResponseWriter, r *http.Request) {
h.Lock()
defer h.Unlock()
if h.hasAddrs {
w.Write([]byte("ok"))
} else {
http.Error(w, "node currently has no tailscale IPs", http.StatusInternalServerError)
}
}
// runHealthz runs a simple HTTP health endpoint on /healthz, listening on the
// provided address. A containerized tailscale instance is considered healthy if
// it has at least one tailnet IP address.
func runHealthz(addr string, h *healthz) {
lis, err := net.Listen("tcp", addr)
if err != nil {
log.Fatalf("error listening on the provided health endpoint address %q: %v", addr, err)
}
mux := http.NewServeMux()
mux.Handle("/healthz", h)
log.Printf("Running healthcheck endpoint at %s/healthz", addr)
hs := &http.Server{Handler: mux}
go func() {
if err := hs.Serve(lis); err != nil {
log.Fatalf("failed running health endpoint: %v", err)
}
}()
}