feat: implement json marshal and unmarshal methods for wireguard key

go.mod

@@ -18,7 +18,7 @@ require (
 	github.com/shirou/gopsutil/v4 v4.24.11
 	github.com/showwin/speedtest-go v1.7.9
 	github.com/spf13/cobra v1.8.1
-	github.com/spf13/viper v1.19.0
+	github.com/spf13/pflag v1.0.5
 	github.com/v2fly/v2ray-core/v5 v5.23.0
 	golang.org/x/crypto v0.31.0
 	google.golang.org/grpc v1.69.4
@@ -126,7 +126,7 @@ require (
 	github.com/sourcegraph/conc v0.3.0 // indirect
 	github.com/spf13/afero v1.11.0 // indirect
 	github.com/spf13/cast v1.6.0 // indirect
-	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/spf13/viper v1.19.0 // indirect
 	github.com/stretchr/testify v1.9.0 // indirect
 	github.com/subosito/gotenv v1.6.0 // indirect
 	github.com/syndtr/goleveldb v1.0.1-0.20220721030215-126854af5e6d // indirect

wireguard/crypto.go

@@ -4,6 +4,7 @@ import (
 	"crypto/rand"
 	"crypto/subtle"
 	"encoding/base64"
+	"encoding/json"
 	"errors"
 	"fmt"
 
@@ -33,6 +34,27 @@ func (k *Key) Public() *Key {
 	return (*Key)(&pub)
 }
 
+// MarshalJSON encodes the Key as a base64 string.
+func (k *Key) MarshalJSON() ([]byte, error) {
+	return json.Marshal(k.String())
+}
+
+// UnmarshalJSON decodes a base64 string into a Key.
+func (k *Key) UnmarshalJSON(data []byte) error {
+	var s string
+	if err := json.Unmarshal(data, &s); err != nil {
+		return fmt.Errorf("failed to unmarshal key: %w", err)
+	}
+
+	key, err := NewKeyFromString(s)
+	if err != nil {
+		return fmt.Errorf("failed to decode key: %w", err)
+	}
+
+	*k = *key
+	return nil
+}
+
 // NewPresharedKey generates a new random 32-byte key.
 func NewPresharedKey() (*Key, error) {
 	var k Key