[#120] Add utility command to sign bearer token in CLI

Signed-off-by: Alex Vanin <alexey@nspcc.ru>

cmd/neofs-cli/modules/util.go

@@ -0,0 +1,122 @@
+package cmd
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io/ioutil"
+
+	"github.com/nspcc-dev/neofs-api-go/pkg"
+	"github.com/nspcc-dev/neofs-api-go/pkg/token"
+	v2ACL "github.com/nspcc-dev/neofs-api-go/v2/acl"
+	"github.com/spf13/cobra"
+)
+
+var (
+	utilCmd = &cobra.Command{
+		Use:   "util",
+		Short: "Utility operations",
+	}
+
+	signCmd = &cobra.Command{
+		Use:   "sign",
+		Short: "sign NeoFS structure",
+	}
+
+	signBearerCmd = &cobra.Command{
+		Use:   "bearer-token",
+		Short: "sign bearer token to use it in requests",
+		RunE:  signBearerToken,
+	}
+)
+
+func init() {
+	rootCmd.AddCommand(utilCmd)
+
+	utilCmd.AddCommand(signCmd)
+
+	signCmd.AddCommand(signBearerCmd)
+	signBearerCmd.Flags().String("from", "", "File with JSON or binary encoded bearer token to sign")
+	_ = signBearerCmd.MarkFlagFilename("from")
+	_ = signBearerCmd.MarkFlagRequired("from")
+	signBearerCmd.Flags().String("to", "", "File to dump signed bearer token")
+	signBearerCmd.Flags().Bool("json", false, "Dump bearer token in JSON encoding")
+}
+
+func signBearerToken(cmd *cobra.Command, _ []string) error {
+	btok, err := getBearerToken(cmd, "from")
+	if err != nil {
+		return err
+	}
+
+	key, err := getKey()
+	if err != nil {
+		return err
+	}
+
+	err = completeBearerToken(btok)
+	if err != nil {
+		return err
+	}
+
+	err = btok.SignToken(key)
+	if err != nil {
+		return err
+	}
+
+	to := cmd.Flag("to").Value.String()
+	jsonFlag, _ := cmd.Flags().GetBool("json")
+
+	var data []byte
+	if jsonFlag || len(to) == 0 {
+		data = v2ACL.BearerTokenToJSON(btok.ToV2())
+		if len(data) == 0 {
+			return errors.New("can't JSON encode bearer token")
+		}
+	} else {
+		data, err = btok.ToV2().StableMarshal(nil)
+		if err != nil {
+			return errors.New("can't binary encode bearer token")
+		}
+	}
+
+	if len(to) == 0 {
+		prettyPrintJSON(cmd, data)
+
+		return nil
+	}
+
+	err = ioutil.WriteFile(to, data, 0644)
+	if err != nil {
+		return fmt.Errorf("can't write signed bearer token to file: %w", err)
+	}
+
+	cmd.Printf("signed bearer token was successfully dumped to %s\n", to)
+
+	return nil
+}
+
+func completeBearerToken(btok *token.BearerToken) error {
+	if v2 := btok.ToV2(); v2 != nil {
+		// set eACL table version, because it usually omitted
+		table := v2.GetBody().GetEACL()
+		table.SetVersion(pkg.SDKVersion().ToV2())
+
+		// back to SDK token
+		btok = token.NewBearerTokenFromV2(v2)
+	} else {
+		return errors.New("unsupported bearer token version")
+	}
+
+	return nil
+}
+
+func prettyPrintJSON(cmd *cobra.Command, data []byte) {
+	buf := new(bytes.Buffer)
+	if err := json.Indent(buf, data, "", "  "); err != nil {
+		printVerbose("Can't pretty print json: %w", err)
+	}
+
+	cmd.Println(buf)
+}