filer.remote.sync: exit when directory is unmounted

this will not propagate the deletions back to the cloud

weed/command/filer_remote_sync.go

@@ -12,7 +12,10 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/replication/source"
 	"github.com/chrislusf/seaweedfs/weed/security"
 	"github.com/chrislusf/seaweedfs/weed/util"
+	"github.com/golang/protobuf/proto"
 	"google.golang.org/grpc"
+	"os"
+	"strings"
 	"time"
 )
 
@@ -102,8 +105,6 @@ func followUpdatesAndUploadToRemote(option *RemoteSyncOptions, filerSource *sour
 		return fmt.Errorf("read mount info: %v", detectErr)
 	}
 
-	dirHash := util.HashStringToLong(mountedDir)
-
 	// 1. specified by timeAgo
 	// 2. last offset timestamp for this directory
 	// 3. directory creation time
@@ -114,7 +115,7 @@ func followUpdatesAndUploadToRemote(option *RemoteSyncOptions, filerSource *sour
 			return fmt.Errorf("lookup %s: %v", mountedDir, err)
 		}
 
-		lastOffsetTsNs, err := getOffset(option.grpcDialOption, *option.filerAddress, RemoteSyncKeyPrefix, int32(dirHash))
+		lastOffsetTsNs, err := remote_storage.GetSyncOffset(option.grpcDialOption, *option.filerAddress, mountedDir)
 		if mountedDirEntry != nil {
 			if err == nil && mountedDirEntry.Attributes.Crtime < lastOffsetTsNs/1000000 {
 				lastOffsetTs = time.Unix(0, lastOffsetTsNs)
@@ -134,8 +135,44 @@ func followUpdatesAndUploadToRemote(option *RemoteSyncOptions, filerSource *sour
 		return err
 	}
 
+	handleEtcRemoteChanges := func(resp *filer_pb.SubscribeMetadataResponse) error {
+		message := resp.EventNotification
+		if message.NewEntry == nil {
+			return nil
+		}
+		if message.NewEntry.Name == filer.REMOTE_STORAGE_MOUNT_FILE {
+			mappings, readErr := filer.UnmarshalRemoteStorageMappings(message.NewEntry.Content)
+			if readErr != nil {
+				return fmt.Errorf("unmarshal mappings: %v", readErr)
+			}
+			if remoteLoc, found := mappings.Mappings[mountedDir]; found {
+				if remoteStorageMountLocation.Bucket != remoteLoc.Bucket || remoteStorageMountLocation.Path != remoteLoc.Path {
+					glog.Fatalf("Unexpected mount changes %+v => %+v", remoteStorageMountLocation, remoteLoc)
+				}
+			} else {
+				glog.V(0).Infof("unmounted %s exiting ...", mountedDir)
+				os.Exit(0)
+			}
+		}
+		if message.NewEntry.Name == remoteStorage.Name + filer.REMOTE_STORAGE_CONF_SUFFIX {
+			conf := &remote_pb.RemoteConf{}
+			if err := proto.Unmarshal(message.NewEntry.Content, conf); err != nil {
+				return fmt.Errorf("unmarshal %s/%s: %v", filer.DirectoryEtcRemote, message.NewEntry.Name, err)
+			}
+			remoteStorage = conf
+			client, err = remote_storage.GetRemoteStorage(remoteStorage)
+			return err
+		}
+
+		return nil
+	}
+
 	eachEntryFunc := func(resp *filer_pb.SubscribeMetadataResponse) error {
 		message := resp.EventNotification
+		if strings.HasPrefix(resp.Directory, filer.DirectoryEtcRemote) {
+			return handleEtcRemoteChanges(resp)
+		}
+
 		if message.OldEntry == nil && message.NewEntry == nil {
 			return nil
 		}
@@ -207,11 +244,11 @@ func followUpdatesAndUploadToRemote(option *RemoteSyncOptions, filerSource *sour
 	processEventFnWithOffset := pb.AddOffsetFunc(eachEntryFunc, 3*time.Second, func(counter int64, lastTsNs int64) error {
 		lastTime := time.Unix(0, lastTsNs)
 		glog.V(0).Infof("remote sync %s progressed to %v %0.2f/sec", *option.filerAddress, lastTime, float64(counter)/float64(3))
-		return setOffset(option.grpcDialOption, *option.filerAddress, RemoteSyncKeyPrefix, int32(dirHash), lastTsNs)
+		return remote_storage.SetSyncOffset(option.grpcDialOption, *option.filerAddress, mountedDir, lastTsNs)
 	})
 
 	return pb.FollowMetadata(*option.filerAddress, option.grpcDialOption, "filer.remote.sync",
-		mountedDir, nil, lastOffsetTs.UnixNano(), 0, processEventFnWithOffset, false)
+		mountedDir, []string{filer.DirectoryEtcRemote}, lastOffsetTs.UnixNano(), 0, processEventFnWithOffset, false)
 }
 
 func toRemoteStorageLocation(mountDir, sourcePath util.FullPath, remoteMountLocation *remote_pb.RemoteStorageLocation) *remote_pb.RemoteStorageLocation {