lock returns host and owner

1 files changed, 49 insertions, 58 deletions

diff --git a/weed/cluster/lock_client.go b/weed/cluster/lock_client.go
index 5c17e1918..f212f9ea0 100644
--- a/weed/cluster/lock_client.go
+++ b/weed/cluster/lock_client.go
@@ -35,9 +35,10 @@ type LiveLock struct {
 	filer          pb.ServerAddress
 	cancelCh       chan struct{}
 	grpcDialOption grpc.DialOption
-	isLocked       bool
-	owner          string
-	lc             *LockClient
+	isLocked bool
+	self     string
+	lc       *LockClient
+	owner	string
 }
 
 // NewShortLivedLock creates a lock with a 5-second duration
@@ -48,27 +49,50 @@ func (lc *LockClient) NewShortLivedLock(key string, owner string) (lock *LiveLoc
 		cancelCh:       make(chan struct{}),
 		expireAtNs:     time.Now().Add(5*time.Second).UnixNano(),
 		grpcDialOption: lc.grpcDialOption,
-		owner:          owner,
+		self:           owner,
 		lc:             lc,
 	}
 	lock.retryUntilLocked(5*time.Second)
 	return
 }
 
-// StartLock starts a goroutine to lock the key and returns immediately.
-func (lc *LockClient) StartLock(key string, owner string) (lock *LiveLock) {
+// StartLongLivedLock starts a goroutine to lock the key and returns immediately.
+func (lc *LockClient) StartLongLivedLock(key string, owner string, onLockOwnerChange func(newLockOwner string)) (lock *LiveLock) {
 	lock = &LiveLock{
 		key:            key,
 		filer:          lc.seedFiler,
 		cancelCh:       make(chan struct{}),
 		expireAtNs:     time.Now().Add(lock_manager.MaxDuration).UnixNano(),
 		grpcDialOption: lc.grpcDialOption,
-		owner:          owner,
+		self:           owner,
 		lc:             lc,
 	}
 	go func() {
-		lock.retryUntilLocked(lock_manager.MaxDuration)
-		lc.keepLock(lock)
+		isLocked := false
+		lockOwner := ""
+		for {
+			if isLocked {
+				if err := lock.AttemptToLock(lock_manager.MaxDuration); err != nil {
+					glog.V(0).Infof("Lost lock %s: %v", key, err)
+					isLocked = false
+				}
+			} else {
+				if err := lock.AttemptToLock(lock_manager.MaxDuration); err == nil {
+					isLocked = true
+				}
+			}
+			if lockOwner != lock.LockOwner() && lock.LockOwner() != "" {
+				glog.V(0).Infof("Lock owner changed from %s to %s", lockOwner, lock.LockOwner())
+				onLockOwnerChange(lock.LockOwner())
+				lockOwner = lock.LockOwner()
+			}
+			select {
+			case <-lock.cancelCh:
+				return
+			default:
+				time.Sleep(5*time.Second)
+			}
+		}
 	}()
 	return
 }
@@ -118,51 +142,6 @@ func (lock *LiveLock) StopShortLivedLock() error {
 	})
 }
 
-func (lc *LockClient) keepLock(lock *LiveLock) {
-	ticker := time.Tick(lc.sleepDuration)
-	for {
-		select {
-		case <-ticker:
-			// renew the lock if lock.expireAtNs is still greater than now
-			util.RetryUntil("keep lock:"+lock.key, func() error {
-				lockDuration := time.Duration(lock.expireAtNs-time.Now().UnixNano()) * time.Nanosecond
-				if lockDuration > lc.maxLockDuration {
-					lockDuration = lc.maxLockDuration
-				}
-				if lockDuration <= 0 {
-					return nil
-				}
-
-				errorMessage, err := lock.doLock(lockDuration)
-				if err != nil {
-					lock.isLocked = false
-					time.Sleep(time.Second)
-					glog.V(0).Infof("keep lock %s: %v", lock.key, err)
-					return err
-				}
-				if errorMessage != "" {
-					lock.isLocked = false
-					time.Sleep(time.Second)
-					glog.V(4).Infof("keep lock message %s: %v", lock.key, errorMessage)
-					return fmt.Errorf("keep lock error: %v", errorMessage)
-				}
-				return nil
-			}, func(err error) (shouldContinue bool) {
-				if err == nil {
-					return false
-				}
-				glog.Warningf("keep lock %s: %v", lock.key, err)
-				return true
-			})
-			if !lock.isLocked {
-				return
-			}
-		case <-lock.cancelCh:
-			return
-		}
-	}
-}
-
 func (lock *LiveLock) doLock(lockDuration time.Duration) (errorMessage string, err error) {
 	err = pb.WithFilerClient(false, 0, lock.filer, lock.grpcDialOption, func(client filer_pb.SeaweedFilerClient) error {
 		resp, err := client.DistributedLock(context.Background(), &filer_pb.LockRequest{
@@ -170,19 +149,31 @@ func (lock *LiveLock) doLock(lockDuration time.Duration) (errorMessage string, e
 			SecondsToLock: int64(lockDuration.Seconds()),
 			RenewToken:    lock.renewToken,
 			IsMoved:       false,
-			Owner:         lock.owner,
+			Owner:         lock.self,
 		})
-		if err == nil {
+		if err == nil && resp != nil {
 			lock.renewToken = resp.RenewToken
+		} else {
+			// this can be retried. Need to remember the last valid renewToken
+			// lock.renewToken = ""
 		}
 		if resp != nil {
 			errorMessage = resp.Error
-			if resp.MovedTo != "" {
-				lock.filer = pb.ServerAddress(resp.MovedTo)
+			if resp.LockHostMovedTo != "" {
+				lock.filer = pb.ServerAddress(resp.LockHostMovedTo)
 				lock.lc.seedFiler = lock.filer
 			}
+			if resp.LockOwner != "" {
+				lock.owner = resp.LockOwner
+			} else {
+				lock.owner = ""
+			}
 		}
 		return err
 	})
 	return
 }
+
+func (lock *LiveLock) LockOwner() string {
+	return lock.owner
+}