Draft sign command implementation

See #1953

client/keys/sign.go

@@ -0,0 +1,76 @@
+package keys
+
+import (
+	"fmt"
+	"io/ioutil"
+
+	"github.com/spf13/viper"
+
+	"github.com/cosmos/cosmos-sdk/client"
+	"github.com/cosmos/cosmos-sdk/x/auth"
+	"github.com/spf13/cobra"
+	amino "github.com/tendermint/go-amino"
+)
+
+// GetSignCommand returns the sign command
+func GetSignCommand(codec *amino.Codec) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "sign <file>",
+		Short: "Sign transactions",
+		Long: `Sign transactions created with the --generate-only flag.
+Read a transaction from <file>, sign it, and print the JSON
+encoding of the signed transaction to STDOUT.`,
+		RunE: makeSignCmd(codec),
+		Args: cobra.ExactArgs(1),
+	}
+	cmd.Flags().String(client.FlagName, "", "Name of private key with which to sign")
+	cmd.Flags().String("file", "", "Transaction filename")
+	// cmd.Flags().Bool(client.FlagUseLedger, false, "Store a local reference to a private key on a Ledger device")
+	// cmd.Flags().Uint32(flagAccount, 0, "Account number for HD derivation")
+	// cmd.Flags().Uint32(flagIndex, 0, "Index number for HD derivation")
+	return cmd
+}
+
+func sign(codec *amino.Codec, key string, msg auth.StdSignMsg) ([]byte, error) {
+	keybase, err := GetKeyBase()
+	if err != nil {
+		return nil, err
+	}
+	passphrase, err := GetPassphrase(key)
+	if err != nil {
+		return nil, err
+	}
+	sig, pubkey, err := keybase.Sign(key, passphrase, msg.Bytes())
+	if err != nil {
+		return nil, err
+	}
+
+	sigs := []auth.StdSignature{{
+		AccountNumber: msg.AccountNumber,
+		Sequence:      msg.Sequence,
+		PubKey:        pubkey,
+		Signature:     sig,
+	}}
+
+	return codec.MarshalJSON(auth.NewStdTx(msg.Msgs, msg.Fee, sigs, msg.Memo))
+}
+
+func makeSignCmd(codec *amino.Codec) func(cmd *cobra.Command, args []string) error {
+	return func(cmd *cobra.Command, args []string) (err error) {
+		bytes, err := ioutil.ReadFile(args[0])
+		if err != nil {
+			return
+		}
+		var tx auth.StdSignMsg
+		err = codec.UnmarshalJSON(bytes, &tx)
+		if err != nil {
+			return
+		}
+		bytes, err = sign(codec, viper.GetString(client.FlagName), tx)
+		if err != nil {
+			return
+		}
+		fmt.Printf("%s\n", bytes)
+		return
+	}
+}

cmd/gaia/cmd/gaiacli/main.go

@@ -136,6 +136,7 @@ func main() {
 	// add proxy, version and key info
 	rootCmd.AddCommand(
 		keys.Commands(),
+		keys.GetSignCommand(cdc),
 		client.LineBreak,
 		version.VersionCmd,
 	)