add: login & token validation tapi belum connect ke DB

internal/auth/jwt.go

@@ -0,0 +1,101 @@
+package auth
+
+import (
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/golang-jwt/jwt/v5"
+)
+
+var (
+	ErrInvalidToken = errors.New("invalid token")
+	ErrExpiredToken = errors.New("token has expired")
+)
+
+// JWTManager handles JWT token operations
+type JWTManager struct {
+	secretKey     string
+	accessExpiry  time.Duration
+	refreshExpiry time.Duration
+}
+
+// NewJWTManager creates a new JWT manager
+func NewJWTManager(secretKey string, accessExpiry, refreshExpiry time.Duration) *JWTManager {
+	return &JWTManager{
+		secretKey:     secretKey,
+		accessExpiry:  accessExpiry,
+		refreshExpiry: refreshExpiry,
+	}
+}
+
+// CustomClaims contains the claims we want in our tokens
+type CustomClaims struct {
+	UserID    string `json:"user_id"`
+	Email     string `json:"email"`
+	Role      string `json:"role"`
+	TokenType string `json:"token_type"` // access or refresh
+	jwt.RegisteredClaims
+}
+
+// GenerateAccessToken creates a new access token
+func (m *JWTManager) GenerateAccessToken(userID, email, role string) (string, error) {
+	claims := CustomClaims{
+		UserID:    userID,
+		Email:     email,
+		Role:      role,
+		TokenType: "access",
+		RegisteredClaims: jwt.RegisteredClaims{
+			ExpiresAt: jwt.NewNumericDate(time.Now().Add(m.accessExpiry)),
+			IssuedAt:  jwt.NewNumericDate(time.Now()),
+		},
+	}
+
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
+	return token.SignedString([]byte(m.secretKey))
+}
+
+// GenerateRefreshToken creates a new refresh token
+func (m *JWTManager) GenerateRefreshToken(userID, email, role string) (string, error) {
+	claims := CustomClaims{
+		UserID:    userID,
+		Email:     email,
+		Role:      role,
+		TokenType: "refresh",
+		RegisteredClaims: jwt.RegisteredClaims{
+			ExpiresAt: jwt.NewNumericDate(time.Now().Add(m.refreshExpiry)),
+			IssuedAt:  jwt.NewNumericDate(time.Now()),
+		},
+	}
+
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
+	return token.SignedString([]byte(m.secretKey))
+}
+
+// ValidateToken validates a token and returns the claims
+func (m *JWTManager) ValidateToken(tokenString string) (*CustomClaims, error) {
+	token, err := jwt.ParseWithClaims(
+		tokenString,
+		&CustomClaims{},
+		func(token *jwt.Token) (interface{}, error) {
+			if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
+				return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
+			}
+			return []byte(m.secretKey), nil
+		},
+	)
+
+	if err != nil {
+		if errors.Is(err, jwt.ErrTokenExpired) {
+			return nil, ErrExpiredToken
+		}
+		return nil, ErrInvalidToken
+	}
+
+	claims, ok := token.Claims.(*CustomClaims)
+	if !ok || !token.Valid {
+		return nil, ErrInvalidToken
+	}
+
+	return claims, nil
+}