I am batman

services/auth-service/internal/utils/utils.go

@@ -0,0 +1,101 @@
+package utils
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"errors"
+	"log"
+	"os"
+	"time"
+
+	"go-microservices/services/auth-service/internal/models"
+
+	"github.com/golang-jwt/jwt/v4"
+)
+
+var (
+	accessTokenSecret  []byte
+	refreshTokenSecret []byte
+)
+
+func init() {
+	access := os.Getenv("JWT_ACCESS_SECRET")
+	if access == "" {
+		access = os.Getenv("JWT_SECRET")
+	}
+	refresh := os.Getenv("JWT_REFRESH_SECRET")
+	if refresh == "" {
+		refresh = os.Getenv("JWT_SECRET")
+	}
+
+	accessTokenSecret = []byte(access)
+	refreshTokenSecret = []byte(refresh)
+}
+
+// GenerateJWT generates an access token and refresh token for the provided user.
+// The function expects the provided models.Auth (or models.User) to have ID, Email and Role fields.
+func GenerateJWT(user models.Auth) (string, string, error) {
+	accessClaims := jwt.MapClaims{
+		"sub":   user.ID,
+		"email": user.Email,
+		"role":  user.Role,
+		"exp":   time.Now().Add(15 * time.Minute).Unix(),
+		"iat":   time.Now().Unix(),
+	}
+
+	accessToken := jwt.NewWithClaims(jwt.SigningMethodHS256, accessClaims)
+	signedAccessToken, err := accessToken.SignedString(accessTokenSecret)
+	if err != nil {
+		log.Println("Error generating access token:", err)
+		return "", "", err
+	}
+
+	refreshClaims := jwt.MapClaims{
+		"sub": user.ID,
+		"exp": time.Now().Add(7 * 24 * time.Hour).Unix(),
+		"iat": time.Now().Unix(),
+	}
+
+	refreshToken := jwt.NewWithClaims(jwt.SigningMethodHS256, refreshClaims)
+	signedRefreshToken, err := refreshToken.SignedString(refreshTokenSecret)
+	if err != nil {
+		log.Println("Error generating refresh token:", err)
+		return "", "", err
+	}
+
+	return signedAccessToken, signedRefreshToken, nil
+}
+
+// ValidateJWT parses and validates the provided token string.
+// If isRefreshToken is true, the refresh secret is used; otherwise the access secret is used.
+func ValidateJWT(tokenString string, isRefreshToken bool) (jwt.MapClaims, error) {
+	secret := accessTokenSecret
+	if isRefreshToken {
+		secret = refreshTokenSecret
+	}
+
+	token, err := jwt.Parse(tokenString, func(token *jwt.Token) (interface{}, error) {
+		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
+			return nil, jwt.NewValidationError("invalid signing method", jwt.ValidationErrorSignatureInvalid)
+		}
+		return secret, nil
+	})
+	if err != nil {
+		return nil, err
+	}
+	claims, ok := token.Claims.(jwt.MapClaims)
+	if !ok || !token.Valid {
+		return nil, errors.New("invalid token")
+	}
+	return claims, nil
+}
+
+// GenerateRandomToken returns a 128-bit random hex token (32 chars).
+func GenerateRandomToken() string {
+	bytes := make([]byte, 16)
+	_, err := rand.Read(bytes)
+	if err != nil {
+		panic("Failed to generate random token")
+	}
+	return hex.EncodeToString(bytes)
+}