go.etcd.io/etcd@v3.3.27+incompatible/functional/runner/lease_renewer_command.go (about)

     1  // Copyright 2016 The etcd Authors
     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 runner
    16  
    17  import (
    18  	"context"
    19  	"errors"
    20  	"fmt"
    21  	"log"
    22  	"time"
    23  
    24  	"github.com/coreos/etcd/clientv3"
    25  
    26  	"github.com/spf13/cobra"
    27  	"google.golang.org/grpc/codes"
    28  	"google.golang.org/grpc/status"
    29  )
    30  
    31  var (
    32  	leaseTTL int64
    33  )
    34  
    35  // NewLeaseRenewerCommand returns the cobra command for "lease-renewer runner".
    36  func NewLeaseRenewerCommand() *cobra.Command {
    37  	cmd := &cobra.Command{
    38  		Use:   "lease-renewer",
    39  		Short: "Performs lease renew operation",
    40  		Run:   runLeaseRenewerFunc,
    41  	}
    42  	cmd.Flags().Int64Var(&leaseTTL, "ttl", 5, "lease's ttl")
    43  	return cmd
    44  }
    45  
    46  func runLeaseRenewerFunc(cmd *cobra.Command, args []string) {
    47  	if len(args) > 0 {
    48  		ExitWithError(ExitBadArgs, errors.New("lease-renewer does not take any argument"))
    49  	}
    50  
    51  	eps := endpointsFromFlag(cmd)
    52  	c := newClient(eps, dialTimeout)
    53  	ctx := context.Background()
    54  
    55  	for {
    56  		var (
    57  			l   *clientv3.LeaseGrantResponse
    58  			lk  *clientv3.LeaseKeepAliveResponse
    59  			err error
    60  		)
    61  		for {
    62  			l, err = c.Lease.Grant(ctx, leaseTTL)
    63  			if err == nil {
    64  				break
    65  			}
    66  		}
    67  		expire := time.Now().Add(time.Duration(l.TTL-1) * time.Second)
    68  
    69  		for {
    70  			lk, err = c.Lease.KeepAliveOnce(ctx, l.ID)
    71  			if ev, ok := status.FromError(err); ok && ev.Code() == codes.NotFound {
    72  				if time.Since(expire) < 0 {
    73  					log.Fatalf("bad renew! exceeded: %v", time.Since(expire))
    74  					for {
    75  						lk, err = c.Lease.KeepAliveOnce(ctx, l.ID)
    76  						fmt.Println(lk, err)
    77  						time.Sleep(time.Second)
    78  					}
    79  				}
    80  				log.Fatalf("lost lease %d, expire: %v\n", l.ID, expire)
    81  				break
    82  			}
    83  			if err != nil {
    84  				continue
    85  			}
    86  			expire = time.Now().Add(time.Duration(lk.TTL-1) * time.Second)
    87  			log.Printf("renewed lease %d, expire: %v\n", lk.ID, expire)
    88  			time.Sleep(time.Duration(lk.TTL-2) * time.Second)
    89  		}
    90  	}
    91  }