all: implement command "export"

The "export" command export all issuers to file or standard output,

	$ gotp export <FORMAT> [FILE]

List of known supported FORMAT is: uri.
If FILE is not defined it will print to standard output.
The list of exported issuers are printed in order of its label.

1 files changed, 43 insertions, 0 deletions

diff --git a/cli.go b/cli.go
index a28f40a..a2bcbf5 100644
--- a/cli.go
+++ b/cli.go
@@ -7,6 +7,7 @@ import (
 	_ "embed"
 	"encoding/base32"
 	"fmt"
+	"io"
 	"os"
 	"path/filepath"
 	"sort"
@@ -72,6 +73,48 @@ func (cli *Cli) Add(issuer *Issuer) (err error) {
 	return nil
 }
 
+// Export all the issuers and its secret to the file or standard output.
+// List of supported format: "uri".
+func (cli *Cli) Export(w io.Writer, formatName string) (err error) {
+	var logp = `Export`
+
+	formatName = strings.ToLower(formatName)
+	switch formatName {
+	case formatNameURI:
+	default:
+		return fmt.Errorf(`%s: unknown format name %q`, logp, formatName)
+	}
+
+	err = cli.cfg.loadPrivateKey()
+	if err != nil {
+		return fmt.Errorf(`%s: %w`, logp, err)
+	}
+
+	var (
+		labels  = cli.List()
+		issuers = make([]*Issuer, 0, len(labels))
+
+		label  string
+		issuer *Issuer
+	)
+	for _, label = range labels {
+		issuer, err = cli.cfg.get(label)
+		if err != nil {
+			return fmt.Errorf(`%s: %w`, logp, err)
+		}
+		issuers = append(issuers, issuer)
+	}
+
+	if formatName == formatNameURI {
+		err = exportAsURI(w, issuers)
+		if err != nil {
+			return fmt.Errorf(`%s: %w`, logp, err)
+		}
+	}
+
+	return nil
+}
+
 // Generate n number of OTP from given issuer name.
 func (cli *Cli) Generate(label string, n int) (listOtp []string, err error) {
 	var (