go-quasar-partial-ssr/backend/internal/auth/service.go

150 lines
3.6 KiB
Go

package auth
import (
"errors"
"time"
"github.com/gofiber/fiber/v3"
"github.com/golang-jwt/jwt/v5"
)
type AuthService struct {
cfg Config
secret []byte
accessExpiry time.Duration
refreshExpiry time.Duration
}
const (
tokenTypeAccess = "access"
tokenTypeRefresh = "refresh"
)
func NewAuthService(cfg Config) (*AuthService, error) {
if cfg.Secret == "" {
return nil, errors.New("jwt secret is required")
}
if cfg.AccessTokenExpiry <= 0 {
return nil, errors.New("access token expiry must be positive")
}
if cfg.RefreshTokenExpiry <= 0 {
return nil, errors.New("refresh token expiry must be positive")
}
return &AuthService{
cfg: cfg,
secret: []byte(cfg.Secret),
accessExpiry: cfg.AccessTokenExpiry,
refreshExpiry: cfg.RefreshTokenExpiry,
}, nil
}
func (s *AuthService) GenerateTokenPair(username string) (TokenPair, error) {
access, err := s.generateToken(username, tokenTypeAccess, s.accessExpiry)
if err != nil {
return TokenPair{}, err
}
refresh, err := s.generateToken(username, tokenTypeRefresh, s.refreshExpiry)
if err != nil {
return TokenPair{}, err
}
return TokenPair{
AccessToken: access,
RefreshToken: refresh,
}, nil
}
func (s *AuthService) AccessExpiry() time.Duration {
return s.accessExpiry
}
func (s *AuthService) RefreshExpiry() time.Duration {
return s.refreshExpiry
}
func (s *AuthService) Middleware() fiber.Handler {
return func(c fiber.Ctx) error {
tokenString := c.Get("Auth-Token")
if tokenString == "" {
return fiber.NewError(fiber.StatusUnauthorized, "missing token header")
}
claims, err := s.parseToken(tokenString)
if err != nil {
return fiber.NewError(fiber.StatusUnauthorized, err.Error())
}
if claims.TokenType != tokenTypeAccess {
return fiber.NewError(fiber.StatusUnauthorized, "access token required")
}
c.Locals("authClaims", claims)
return c.Next()
}
}
func (s *AuthService) Refresh(refreshToken string) (TokenPair, error) {
claims, err := s.parseToken(refreshToken)
if err != nil {
return TokenPair{}, err
}
if claims.TokenType != tokenTypeRefresh {
return TokenPair{}, errors.New("refresh token required")
}
return s.GenerateTokenPair(claims.Username)
}
func (s *AuthService) ValidateAccessToken(tokenString string) (*Claims, error) {
claims, err := s.parseToken(tokenString)
if err != nil {
return nil, err
}
if claims.TokenType != tokenTypeAccess {
return nil, errors.New("access token required")
}
return claims, nil
}
func ClaimsFromCtx(c fiber.Ctx) (*Claims, bool) {
val := c.Locals("authClaims")
if val == nil {
return nil, false
}
claims, ok := val.(*Claims)
return claims, ok
}
func (s *AuthService) parseToken(tokenString string) (*Claims, error) {
claims := &Claims{}
token, err := jwt.ParseWithClaims(tokenString, claims, func(t *jwt.Token) (interface{}, error) {
if _, ok := t.Method.(*jwt.SigningMethodHMAC); !ok {
return nil, fiber.ErrUnauthorized
}
return s.secret, nil
})
if err != nil || !token.Valid {
return nil, errors.New("invalid or expired token")
}
if s.cfg.Issuer != "" && claims.Issuer != "" && claims.Issuer != s.cfg.Issuer {
return nil, errors.New("invalid token issuer")
}
return claims, nil
}
func (s *AuthService) generateToken(username, tokenType string, expiry time.Duration) (string, error) {
claims := Claims{
Username: username,
TokenType: tokenType,
RegisteredClaims: jwt.RegisteredClaims{
Issuer: s.cfg.Issuer,
ExpiresAt: jwt.NewNumericDate(time.Now().Add(expiry)),
IssuedAt: jwt.NewNumericDate(time.Now()),
},
}
token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
return token.SignedString(s.secret)
}