github.com/zppinho/prow@v0.0.0-20240510014325-1738badeb017/pkg/pjutil/health.go (about)

     1  /*
     2  Copyright 2019 The Kubernetes Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  // Package pjutil contains helpers for working with ProwJobs.
    18  package pjutil
    19  
    20  import (
    21  	"fmt"
    22  	"net/http"
    23  	"strconv"
    24  	"time"
    25  
    26  	"sigs.k8s.io/prow/pkg/interrupts"
    27  )
    28  
    29  const healthPort = 8081
    30  
    31  // Health keeps a request multiplexer for health liveness and readiness endpoints
    32  type Health struct {
    33  	healthMux *http.ServeMux
    34  }
    35  
    36  // NewHealth creates a new health request multiplexer and starts serving the liveness endpoint
    37  // on the default port
    38  func NewHealth() *Health {
    39  	return NewHealthOnPort(healthPort)
    40  }
    41  
    42  // NewHealth creates a new health request multiplexer and starts serving the liveness endpoint
    43  // on the given port
    44  func NewHealthOnPort(port int) *Health {
    45  	healthMux := http.NewServeMux()
    46  	healthMux.HandleFunc("/healthz", func(w http.ResponseWriter, r *http.Request) { fmt.Fprint(w, "OK") })
    47  	server := &http.Server{Addr: ":" + strconv.Itoa(port), Handler: healthMux}
    48  	interrupts.ListenAndServe(server, 5*time.Second)
    49  	return &Health{
    50  		healthMux: healthMux,
    51  	}
    52  }
    53  
    54  type ReadynessCheck func() bool
    55  
    56  // ServeReady starts serving the readiness endpoint
    57  func (h *Health) ServeReady(readynessChecks ...ReadynessCheck) {
    58  	h.healthMux.HandleFunc("/healthz/ready", func(w http.ResponseWriter, r *http.Request) {
    59  		for _, readynessCheck := range readynessChecks {
    60  			if !readynessCheck() {
    61  				w.WriteHeader(http.StatusServiceUnavailable)
    62  				fmt.Fprint(w, "ReadynessCheck failed")
    63  				return
    64  			}
    65  		}
    66  		fmt.Fprint(w, "OK")
    67  	})
    68  }