Merge pull request #1710 from filecoin-project/feat/bitfield-decode-shed

add method to decode and print all bitfield entries to lotus shed

cmd/lotus-shed/bitfield.go

@@ -10,6 +10,7 @@ import (
 	"golang.org/x/xerrors"
 	"gopkg.in/urfave/cli.v2"
 
+	"github.com/filecoin-project/go-bitfield"
 	rlepluslazy "github.com/filecoin-project/go-bitfield/rle"
 )
 
@@ -26,6 +27,7 @@ var bitFieldCmd = &cli.Command{
 	Subcommands: []*cli.Command{
 		bitFieldRunsCmd,
 		bitFieldStatCmd,
+		bitFieldDecodeCmd,
 	},
 }
 
@@ -186,3 +188,58 @@ var bitFieldStatCmd = &cli.Command{
 		return nil
 	},
 }
+
+var bitFieldDecodeCmd = &cli.Command{
+	Name:        "decode",
+	Description: "decode bitfield and print all numbers in it",
+	Flags: []cli.Flag{
+		&cli.StringFlag{
+			Name:  "enc",
+			Value: "base64",
+			Usage: "specify input encoding to parse",
+		},
+	},
+	Action: func(cctx *cli.Context) error {
+		var val string
+		if cctx.Args().Present() {
+			val = cctx.Args().Get(0)
+		} else {
+			b, err := ioutil.ReadAll(os.Stdin)
+			if err != nil {
+				return err
+			}
+			val = string(b)
+		}
+
+		var dec []byte
+		switch cctx.String("enc") {
+		case "base64":
+			d, err := base64.StdEncoding.DecodeString(val)
+			if err != nil {
+				return fmt.Errorf("decoding base64 value: %w", err)
+			}
+			dec = d
+		case "hex":
+			d, err := hex.DecodeString(val)
+			if err != nil {
+				return fmt.Errorf("decoding hex value: %w", err)
+			}
+			dec = d
+		default:
+			return fmt.Errorf("unrecognized encoding: %s", cctx.String("enc"))
+		}
+
+		rle, err := bitfield.NewFromBytes(dec)
+		if err != nil {
+			return xerrors.Errorf("failed to parse bitfield: %w", err)
+		}
+
+		vals, err := rle.All(100000000000)
+		if err != nil {
+			return xerrors.Errorf("getting all items: %w", err)
+		}
+		fmt.Println(vals)
+
+		return nil
+	},
+}