1 files changed, 161 insertions, 0 deletions
diff --git a/weed/server/filer_grpc_server_remote.go b/weed/server/filer_grpc_server_remote.go
new file mode 100644
index 000000000..93953f99d
--- /dev/null
+++ b/weed/server/filer_grpc_server_remote.go
@@ -0,0 +1,161 @@
+package weed_server
+
+import (
+	"context"
+	"fmt"
+	"github.com/chrislusf/seaweedfs/weed/filer"
+	"github.com/chrislusf/seaweedfs/weed/operation"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/pb/volume_server_pb"
+	"github.com/chrislusf/seaweedfs/weed/storage/needle"
+	"github.com/chrislusf/seaweedfs/weed/util"
+	"github.com/golang/protobuf/proto"
+	"strings"
+	"time"
+)
+
+func (fs *FilerServer) DownloadToLocal(ctx context.Context, req *filer_pb.DownloadToLocalRequest) (*filer_pb.DownloadToLocalResponse, error) {
+
+	// load all mappings
+	mappingEntry, err := fs.filer.FindEntry(ctx, util.JoinPath(filer.DirectoryEtcRemote, filer.REMOTE_STORAGE_MOUNT_FILE))
+	if err != nil {
+		return nil, err
+	}
+	mappings, err := filer.UnmarshalRemoteStorageMappings(mappingEntry.Content)
+	if err != nil {
+		return nil, err
+	}
+
+	// find mapping
+	var remoteStorageMountedLocation *filer_pb.RemoteStorageLocation
+	var localMountedDir string
+	for k, loc := range mappings.Mappings {
+		if strings.HasPrefix(req.Directory, k) {
+			localMountedDir, remoteStorageMountedLocation = k, loc
+		}
+	}
+	if localMountedDir == "" {
+		return nil, fmt.Errorf("%s is not mounted", req.Directory)
+	}
+
+	// find storage configuration
+	storageConfEntry, err := fs.filer.FindEntry(ctx, util.JoinPath(filer.DirectoryEtcRemote, remoteStorageMountedLocation.Name+filer.REMOTE_STORAGE_CONF_SUFFIX))
+	if err != nil {
+		return nil, err
+	}
+	storageConf := &filer_pb.RemoteConf{}
+	if unMarshalErr := proto.Unmarshal(storageConfEntry.Content, storageConf); unMarshalErr != nil {
+		return nil, fmt.Errorf("unmarshal remote storage conf %s/%s: %v", filer.DirectoryEtcRemote, remoteStorageMountedLocation.Name+filer.REMOTE_STORAGE_CONF_SUFFIX, unMarshalErr)
+	}
+
+	// find the entry
+	entry, err := fs.filer.FindEntry(ctx, util.JoinPath(req.Directory, req.Name))
+	if err == filer_pb.ErrNotFound {
+		return nil, err
+	}
+
+	resp := &filer_pb.DownloadToLocalResponse{}
+	if entry.Remote == nil || entry.Remote.RemoteSize == 0 {
+		return resp, nil
+	}
+
+	// detect storage option
+	so, err := fs.detectStorageOption(req.Directory, "", "000", 0, "", "", "")
+	if err != nil {
+		return resp, err
+	}
+	assignRequest, altRequest := so.ToAssignRequests(1)
+
+	// find a good chunk size
+	chunkSize := int64(5 * 1024 * 1024)
+	chunkCount := entry.Remote.RemoteSize/chunkSize + 1
+	for chunkCount > 1000 {
+		chunkSize *= 2
+		chunkCount = entry.Remote.RemoteSize/chunkSize + 1
+	}
+
+	dest := util.FullPath(remoteStorageMountedLocation.Path).Child(string(util.FullPath(req.Directory).Child(req.Name))[len(localMountedDir):])
+
+	var chunks []*filer_pb.FileChunk
+
+	for offset := int64(0); offset < entry.Remote.RemoteSize; offset += chunkSize {
+		size := chunkSize
+		if offset+chunkSize > entry.Remote.RemoteSize {
+			size = entry.Remote.RemoteSize - offset
+		}
+
+		// assign one volume server
+		assignResult, err := operation.Assign(fs.filer.GetMaster, fs.grpcDialOption, assignRequest, altRequest)
+		if err != nil {
+			return resp, err
+		}
+		if assignResult.Error != "" {
+			return resp, fmt.Errorf("assign: %v", assignResult.Error)
+		}
+		fileId, parseErr := needle.ParseFileIdFromString(assignResult.Fid)
+		if assignResult.Error != "" {
+			return resp, fmt.Errorf("unrecognized file id %s: %v", assignResult.Fid, parseErr)
+		}
+
+		// tell filer to tell volume server to download into needles
+		err = operation.WithVolumeServerClient(assignResult.Url, fs.grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+			_, fetchAndWriteErr := volumeServerClient.FetchAndWriteNeedle(context.Background(), &volume_server_pb.FetchAndWriteNeedleRequest{
+				VolumeId:     uint32(fileId.VolumeId),
+				NeedleId:     uint64(fileId.Key),
+				Cookie:       uint32(fileId.Cookie),
+				Offset:       offset,
+				Size:         size,
+				RemoteType:   storageConf.Type,
+				RemoteName:   storageConf.Name,
+				S3AccessKey:  storageConf.S3AccessKey,
+				S3SecretKey:  storageConf.S3SecretKey,
+				S3Region:     storageConf.S3Region,
+				S3Endpoint:   storageConf.S3Endpoint,
+				RemoteBucket: remoteStorageMountedLocation.Bucket,
+				RemotePath:   string(dest),
+			})
+			if fetchAndWriteErr != nil {
+				return fmt.Errorf("volume server %s fetchAndWrite %s/$s: %v", assignResult.Url, req.Directory, req.Name, fetchAndWriteErr)
+			}
+			return nil
+		})
+
+		if err != nil {
+			return nil, err
+		}
+
+		chunks = append(chunks, &filer_pb.FileChunk{
+			FileId: assignResult.Fid,
+			Offset: offset,
+			Size:   uint64(size),
+			Mtime:  time.Now().Unix(),
+			Fid: &filer_pb.FileId{
+				VolumeId: uint32(fileId.VolumeId),
+				FileKey:  uint64(fileId.Key),
+				Cookie:   uint32(fileId.Cookie),
+			},
+		})
+
+	}
+
+	garbage := entry.Chunks
+
+	newEntry := entry.ShallowClone()
+	newEntry.Chunks = chunks
+	newEntry.Remote = proto.Clone(entry.Remote).(*filer_pb.RemoteEntry)
+	newEntry.Remote.LocalMtime = time.Now().Unix()
+
+	// this skips meta data log events
+
+	if err := fs.filer.Store.UpdateEntry(context.Background(), newEntry); err != nil {
+		return nil, err
+	}
+	fs.filer.DeleteChunks(garbage)
+
+	fs.filer.NotifyUpdateEvent(ctx, entry, newEntry, true, false, nil)
+
+	resp.Entry = entry.ToProtoEntry()
+
+	return resp, nil
+
+}