github.com/galamsiva2020/kubernetes-heapster-monitoring@v0.0.0-20210823134957-3c1baa7c1e70/events/api/handler.go (about)

     1  // Copyright 2017 Google Inc. All Rights Reserved.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package api
    16  
    17  import (
    18  	"errors"
    19  	"fmt"
    20  	"net/http"
    21  	"time"
    22  
    23  	"github.com/golang/glog"
    24  	"k8s.io/apiserver/pkg/server/healthz"
    25  	"k8s.io/heapster/events/manager"
    26  )
    27  
    28  const (
    29  	// MaxEventsScrapeDelay should be larger than `frequency` command line argument.
    30  	MaxEventsScrapeDelay = 3 * time.Minute
    31  )
    32  
    33  func healthzChecker() healthz.HealthzChecker {
    34  	return healthz.NamedCheck("healthz", func(r *http.Request) error {
    35  		if time.Since(manager.LatestScrapeTime) > MaxEventsScrapeDelay {
    36  			msg := fmt.Sprintf(
    37  				"No event batch within %s (latest: %s)",
    38  				MaxEventsScrapeDelay,
    39  				manager.LatestScrapeTime,
    40  			)
    41  			glog.Warning(msg)
    42  			return errors.New(msg)
    43  		}
    44  
    45  		return nil
    46  	})
    47  }