1 files changed, 85 insertions, 0 deletions
diff --git a/weed/server/volume_grpc_tier_download.go b/weed/server/volume_grpc_tier_download.go
new file mode 100644
index 000000000..7b3982e40
--- /dev/null
+++ b/weed/server/volume_grpc_tier_download.go
@@ -0,0 +1,85 @@
+package weed_server
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/chrislusf/seaweedfs/weed/pb/volume_server_pb"
+	"github.com/chrislusf/seaweedfs/weed/storage/backend"
+	"github.com/chrislusf/seaweedfs/weed/storage/needle"
+)
+
+// VolumeTierMoveDatFromRemote copy dat file from a remote tier to local volume server
+func (vs *VolumeServer) VolumeTierMoveDatFromRemote(req *volume_server_pb.VolumeTierMoveDatFromRemoteRequest, stream volume_server_pb.VolumeServer_VolumeTierMoveDatFromRemoteServer) error {
+
+	// find existing volume
+	v := vs.store.GetVolume(needle.VolumeId(req.VolumeId))
+	if v == nil {
+		return fmt.Errorf("volume %d not found", req.VolumeId)
+	}
+
+	// verify the collection
+	if v.Collection != req.Collection {
+		return fmt.Errorf("existing collection:%v unexpected input: %v", v.Collection, req.Collection)
+	}
+
+	// locate the disk file
+	storageName, storageKey := v.RemoteStorageNameKey()
+	if storageName == "" || storageKey == "" {
+		return fmt.Errorf("volume %d is already on local disk", req.VolumeId)
+	}
+
+	// check whether the local .dat already exists
+	_, ok := v.DataBackend.(*backend.DiskFile)
+	if ok {
+		return fmt.Errorf("volume %d is already on local disk", req.VolumeId)
+	}
+
+	// check valid storage backend type
+	backendStorage, found := backend.BackendStorages[storageName]
+	if !found {
+		var keys []string
+		for key := range backend.BackendStorages {
+			keys = append(keys, key)
+		}
+		return fmt.Errorf("remote storage %s not found from suppported: %v", storageName, keys)
+	}
+
+	startTime := time.Now()
+	fn := func(progressed int64, percentage float32) error {
+		now := time.Now()
+		if now.Sub(startTime) < time.Second {
+			return nil
+		}
+		startTime = now
+		return stream.Send(&volume_server_pb.VolumeTierMoveDatFromRemoteResponse{
+			Processed:           progressed,
+			ProcessedPercentage: percentage,
+		})
+	}
+	// copy the data file
+	_, err := backendStorage.DownloadFile(v.FileName()+".dat", storageKey, fn)
+	if err != nil {
+		return fmt.Errorf("backend %s copy file %s: %v", storageName, v.FileName()+".dat", err)
+	}
+
+	if req.KeepRemoteDatFile {
+		return nil
+	}
+
+	// remove remote file
+	if err := backendStorage.DeleteFile(storageKey); err != nil {
+		return fmt.Errorf("volume %d fail to delete remote file %s: %v", v.Id, storageKey, err)
+	}
+
+	// forget remote file
+	v.GetVolumeInfo().Files = v.GetVolumeInfo().Files[1:]
+	if err := v.SaveVolumeInfo(); err != nil {
+		return fmt.Errorf("volume %d fail to save remote file info: %v", v.Id, err)
+	}
+
+	v.DataBackend.Close()
+	v.DataBackend = nil
+
+	return nil
+}