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@mayankshah1607
Created October 25, 2021 07:15
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tryAcquireOrRenew
func (le *LeaderElector) tryAcquireOrRenew(ctx context.Context) bool {
now := metav1.Now()
leaderElectionRecord := rl.LeaderElectionRecord{
HolderIdentity: le.config.Lock.Identity(),
LeaseDurationSeconds: int(le.config.LeaseDuration / time.Second),
RenewTime: now,
AcquireTime: now,
}
// 1. obtain or create the ElectionRecord
oldLeaderElectionRecord, oldLeaderElectionRawRecord, err := le.config.Lock.Get(ctx)
if err != nil {
if !errors.IsNotFound(err) {
klog.Errorf("error retrieving resource lock %v: %v", le.config.Lock.Describe(), err)
return false
}
if err = le.config.Lock.Create(ctx, leaderElectionRecord); err != nil {
klog.Errorf("error initially creating leader election record: %v", err)
return false
}
le.setObservedRecord(&leaderElectionRecord)
return true
}
// 2. Record obtained, check the Identity & Time
if !bytes.Equal(le.observedRawRecord, oldLeaderElectionRawRecord) {
le.setObservedRecord(oldLeaderElectionRecord)
le.observedRawRecord = oldLeaderElectionRawRecord
}
if len(oldLeaderElectionRecord.HolderIdentity) > 0 &&
le.observedTime.Add(le.config.LeaseDuration).After(now.Time) &&
!le.IsLeader() {
klog.V(4).Infof("lock is held by %v and has not yet expired", oldLeaderElectionRecord.HolderIdentity)
return false
}
// 3. We're going to try to update. The leaderElectionRecord is set to it's default
// here. Let's correct it before updating.
if le.IsLeader() {
leaderElectionRecord.AcquireTime = oldLeaderElectionRecord.AcquireTime
leaderElectionRecord.LeaderTransitions = oldLeaderElectionRecord.LeaderTransitions
} else {
leaderElectionRecord.LeaderTransitions = oldLeaderElectionRecord.LeaderTransitions + 1
}
// update the lock itself
if err = le.config.Lock.Update(ctx, leaderElectionRecord); err != nil {
klog.Errorf("Failed to update lock: %v", err)
return false
}
le.setObservedRecord(&leaderElectionRecord)
return true
}
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