shard id starts from zero

weed/shell/command_ec_encode.go

@@ -0,0 +1,78 @@
+package shell
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"io"
+
+	"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, &commandEcEncode{})
+}
+
+type commandEcEncode struct {
+}
+
+func (c *commandEcEncode) Name() string {
+	return "ec.encode"
+}
+
+func (c *commandEcEncode) Help() string {
+	return `apply erasure coding to a volume
+
+	This command will:
+	1. freeze one volume
+	2. apply erasure coding to the volume
+	3. move the encoded shards to multiple volume servers
+
+	The erasure coding is 10.4. So ideally you have more than 14 volume servers, and you can afford
+	to lose 4 volume servers.
+
+	If the number of volumes are not high, the worst case is that you only have 4 volume servers,
+	and the shards are spread as 4,4,3,3, respectively. You can afford to lose one volume server.
+
+	If you only have less than 4 volume servers, with erasure coding, at least you can afford to
+	have 4 corrupted shard files.
+
+`
+}
+
+func (c *commandEcEncode) Do(args []string, commandEnv *commandEnv, writer io.Writer) (err error) {
+
+	encodeCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
+	volumeId := encodeCommand.Int("vid", 0, "the volume id")
+	if err = encodeCommand.Parse(args); err != nil {
+		return nil
+	}
+
+	ctx := context.Background()
+
+	locations := commandEnv.masterClient.GetLocations(uint32(*volumeId))
+
+	if len(locations) == 0 {
+		return fmt.Errorf("volume %d not found", *volumeId)
+	}
+
+	err = generateEcSlices(ctx, commandEnv.option.GrpcDialOption, needle.VolumeId(*volumeId), locations[0].Url)
+
+	return err
+}
+
+func generateEcSlices(ctx context.Context, grpcDialOption grpc.DialOption, volumeId needle.VolumeId, sourceVolumeServer string) error {
+
+	err := operation.WithVolumeServerClient(sourceVolumeServer, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
+		_, genErr := volumeServerClient.VolumeEcGenerateSlices(ctx, &volume_server_pb.VolumeEcGenerateSlicesRequest{
+			VolumeId: uint32(volumeId),
+		})
+		return genErr
+	})
+
+	return err
+
+}