feat: 初始提交云印享付费打印服务后端

cloudprint-backend/pkg/jwt/jwt.go

@@ -0,0 +1,105 @@
+package jwt
+
+import (
+	"errors"
+	"time"
+
+	"github.com/golang-jwt/jwt/v5"
+)
+
+var (
+	ErrInvalidToken = errors.New("invalid token")
+	ErrExpiredToken = errors.New("token has expired")
+)
+
+type Claims struct {
+	UserID   int32  `json:"user_id"`
+	UserType string `json:"user_type"` // "user" or "admin"
+	Username string `json:"username,omitempty"`
+	jwt.RegisteredClaims
+}
+
+type JWTManager struct {
+	secretKey       []byte
+	accessTokenTTL  time.Duration
+	refreshTokenTTL time.Duration
+}
+
+func NewJWTManager(secret string, accessTokenTTL, refreshTokenTTL time.Duration) *JWTManager {
+	return &JWTManager{
+		secretKey:       []byte(secret),
+		accessTokenTTL:  accessTokenTTL,
+		refreshTokenTTL: refreshTokenTTL,
+	}
+}
+
+func (m *JWTManager) GenerateAccessToken(userID int32, userType string, username string) (string, error) {
+	now := time.Now()
+	claims := &Claims{
+		UserID:   userID,
+		UserType: userType,
+		Username: username,
+		RegisteredClaims: jwt.RegisteredClaims{
+			ExpiresAt: jwt.NewNumericDate(now.Add(m.accessTokenTTL)),
+			IssuedAt:  jwt.NewNumericDate(now),
+			NotBefore: jwt.NewNumericDate(now),
+		},
+	}
+
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
+	return token.SignedString(m.secretKey)
+}
+
+func (m *JWTManager) GenerateRefreshToken(userID int32, userType string) (string, error) {
+	now := time.Now()
+	claims := &Claims{
+		UserID:   userID,
+		UserType: userType,
+		RegisteredClaims: jwt.RegisteredClaims{
+			ExpiresAt: jwt.NewNumericDate(now.Add(m.refreshTokenTTL)),
+			IssuedAt:  jwt.NewNumericDate(now),
+			NotBefore: jwt.NewNumericDate(now),
+			Subject:   "refresh",
+		},
+	}
+
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
+	return token.SignedString(m.secretKey)
+}
+
+func (m *JWTManager) ValidateToken(tokenString string) (*Claims, error) {
+	token, err := jwt.ParseWithClaims(tokenString, &Claims{}, func(token *jwt.Token) (interface{}, error) {
+		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
+			return nil, ErrInvalidToken
+		}
+		return m.secretKey, nil
+	})
+
+	if err != nil {
+		if errors.Is(err, jwt.ErrTokenExpired) {
+			return nil, ErrExpiredToken
+		}
+		return nil, ErrInvalidToken
+	}
+
+	claims, ok := token.Claims.(*Claims)
+	if !ok || !token.Valid {
+		return nil, ErrInvalidToken
+	}
+
+	return claims, nil
+}
+
+func (m *JWTManager) RefreshAccessToken(refreshToken string) (string, error) {
+	claims, err := m.ValidateToken(refreshToken)
+	if err != nil {
+		return "", err
+	}
+
+	// Only refresh tokens with subject "refresh" can be used
+	if claims.Subject != "refresh" {
+		return "", ErrInvalidToken
+	}
+
+	return m.GenerateAccessToken(claims.UserID, claims.UserType, claims.Username)
+}