first

lib/jwt/jwt.go

@@ -0,0 +1,61 @@
+package jwt
+
+import (
+	"crypto/rsa"
+	"github.com/golang-jwt/jwt/v5"
+	"os"
+	"time"
+)
+
+type Jwt struct {
+	privateKey          *rsa.PrivateKey
+	TokenExpireDuration time.Duration
+}
+
+type UserClaims struct {
+	UserId uint `json:"user_id"`
+	jwt.RegisteredClaims
+}
+
+func NewJwt(privateKeyFile string, tokenExpireDuration time.Duration) *Jwt {
+	privateKeyContent, err := os.ReadFile(privateKeyFile)
+	if err != nil {
+		panic(err)
+	}
+	privateKey, err := jwt.ParseRSAPrivateKeyFromPEM(privateKeyContent)
+	if err != nil {
+		panic(err)
+	}
+	return &Jwt{
+		privateKey:          privateKey,
+		TokenExpireDuration: tokenExpireDuration,
+	}
+}
+
+func (s *Jwt) GenerateToken(userId uint) string {
+	t := jwt.NewWithClaims(jwt.SigningMethodRS256,
+		UserClaims{
+			UserId: userId,
+			RegisteredClaims: jwt.RegisteredClaims{
+				ExpiresAt: jwt.NewNumericDate(time.Now().Add(s.TokenExpireDuration)),
+			},
+		})
+	token, err := t.SignedString(s.privateKey)
+	if err != nil {
+		return ""
+	}
+	return token
+}
+
+func (s *Jwt) ParseToken(tokenString string) (uint, error) {
+	token, err := jwt.ParseWithClaims(tokenString, &UserClaims{}, func(token *jwt.Token) (interface{}, error) {
+		return s.privateKey.Public(), nil
+	})
+	if err != nil {
+		return 0, err
+	}
+	if claims, ok := token.Claims.(*UserClaims); ok && token.Valid {
+		return claims.UserId, nil
+	}
+	return 0, err
+}