shell: add command volume.move

1 files changed, 124 insertions, 0 deletions

diff --git a/weed/shell/command_volume_move.go b/weed/shell/command_volume_move.go
new file mode 100644
index 000000000..771f345ac
--- /dev/null
+++ b/weed/shell/command_volume_move.go
@@ -0,0 +1,124 @@
+package shell
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"log"
+	"time"
+
+	"github.com/chrislusf/seaweedfs/weed/operation"
+	"github.com/chrislusf/seaweedfs/weed/pb/volume_server_pb"
+	"github.com/chrislusf/seaweedfs/weed/storage/needle"
+	"google.golang.org/grpc"
+)
+
+func init() {
+	commands = append(commands, &commandVolumeMove{})
+}
+
+type commandVolumeMove struct {
+	grpcDialOption grpc.DialOption
+}
+
+func (c *commandVolumeMove) Name() string {
+	return "volume.move"
+}
+
+func (c *commandVolumeMove) Help() string {
+	return `move a live volume from one volume server to another volume server
+
+	volume.move <source volume server host:port> <target volume server host:port> <volume id>
+
+	This command move a live volume from one volume server to another volume server. Here are the steps:
+
+	1. This command asks the target volume server to copy the source volume from source volume server, remember the last entry's timestamp.
+	2. This command asks the target volume server to mount the new volume
+		Now the master will mark this volume id as readonly.
+	3. This command asks the target volume server to tail the source volume for updates after the timestamp, for 1 minutes to drain the requests.
+	4. This command asks the source volume server to unmount the source volume
+		Now the master will mark this volume id as writable.
+	5. This command asks the source volume server to delete the source volume
+
+`
+}
+
+func (c *commandVolumeMove) Do(args []string, commandEnv *commandEnv, writer io.Writer) (err error) {
+
+	if len(args) != 3 {
+		fmt.Fprintf(writer, "received args: %+v\n", args)
+		return fmt.Errorf("need 3 args of <source volume server host:port> <target volume server host:port> <volume id>")
+	}
+	c.grpcDialOption = commandEnv.option.GrpcDialOption
+	ctx := context.Background()
+
+	sourceVolumeServer, targetVolumeServer, volumeIdString := args[0], args[1], args[2]
+
+	volumeId, err := needle.NewVolumeId(volumeIdString)
+	if err != nil {
+		return fmt.Errorf("wrong volume id format %s: %v", volumeId, err)
+	}
+
+	if sourceVolumeServer == targetVolumeServer {
+		return fmt.Errorf("source and target volume servers are the same!")
+	}
+
+	log.Printf("copying volume %d from %s to %s", volumeId, sourceVolumeServer, targetVolumeServer)
+	lastAppendAtNs, err := c.copyVolume(ctx, volumeId, sourceVolumeServer, targetVolumeServer)
+	if err != nil {
+		return fmt.Errorf("copy volume %d from %s to %s: %v", volumeId, sourceVolumeServer, targetVolumeServer, err)
+	}
+
+	log.Printf("tailing volume %d from %s to %s", volumeId, sourceVolumeServer, targetVolumeServer)
+	if err = c.tailVolume(ctx, volumeId, sourceVolumeServer, targetVolumeServer, lastAppendAtNs, 5*time.Second); err != nil {
+		return fmt.Errorf("tail volume %d from %s to %s: %v", volumeId, sourceVolumeServer, targetVolumeServer, err)
+	}
+
+	log.Printf("deleting volume %d from %s", volumeId, sourceVolumeServer)
+	if err = c.deleteVolume(ctx, volumeId, sourceVolumeServer); err != nil {
+		return fmt.Errorf("delete volume %d from %s: %v", volumeId, sourceVolumeServer, err)
+	}
+
+	log.Printf("moved volume %d from %s to %s", volumeId, sourceVolumeServer, targetVolumeServer)
+
+	return nil
+}
+
+func (c *commandVolumeMove) copyVolume(ctx context.Context, volumeId needle.VolumeId, sourceVolumeServer, targetVolumeServer string) (lastAppendAtNs uint64, err error) {
+
+	err = operation.WithVolumeServerClient(targetVolumeServer, c.grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		resp, replicateErr := volumeServerClient.VolumeCopy(ctx, &volume_server_pb.VolumeCopyRequest{
+			VolumeId:       uint32(volumeId),
+			SourceDataNode: sourceVolumeServer,
+		})
+		if replicateErr == nil {
+			lastAppendAtNs = resp.LastAppendAtNs
+		}
+		return replicateErr
+	})
+
+	return
+}
+
+func (c *commandVolumeMove) tailVolume(ctx context.Context, volumeId needle.VolumeId, sourceVolumeServer, targetVolumeServer string, lastAppendAtNs uint64, timeout time.Duration) (err error) {
+
+	return operation.WithVolumeServerClient(targetVolumeServer, c.grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, replicateErr := volumeServerClient.VolumeTailReceiver(ctx, &volume_server_pb.VolumeTailReceiverRequest{
+			VolumeId:           uint32(volumeId),
+			SinceNs:            lastAppendAtNs,
+			DrainingSeconds:    uint32(timeout.Seconds()),
+			SourceVolumeServer: sourceVolumeServer,
+		})
+		return replicateErr
+	})
+
+}
+
+func (c *commandVolumeMove) deleteVolume(ctx context.Context, volumeId needle.VolumeId, sourceVolumeServer string) (err error) {
+	return operation.WithVolumeServerClient(sourceVolumeServer, c.grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, unmountErr := volumeServerClient.VolumeDelete(ctx, &volume_server_pb.VolumeDeleteRequest{
+			VolumeId: uint32(volumeId),
+		})
+		return unmountErr
+	})
+}