Added /refresh endpoint and make some refactor again

src/internal/service/auth.go

@@ -6,16 +6,17 @@ import (
 	"fmt"
 
 	db "git.ego.freeddns.org/egommerce/identity-service/pkg/database"
+
 	"github.com/go-redis/redis/v8"
 	"github.com/jackc/pgx/v5/pgxpool"
 )
 
 var (
 	AuthService *Auth
-	jwtSrv      *JWT
 
 	ErrLoginIncorrect     = errors.New("login incorrect")
 	ErrUnableToCacheToken = errors.New("unable to save token in cache")
+	ErrInvalidAccessToken = errors.New("invalid access token")
 )
 
 func init() {
@@ -48,13 +49,30 @@ func (a *Auth) Login(login, passwd string) (string, error) {
 
 	accessToken, _ := jwtSrv.CreateAccessToken(id)
 	refreshToken, _ := jwtSrv.CreateRefreshToken(id)
-	if err = a.saveTokensToCache(accessToken, refreshToken, id); err != nil {
+	if err = a.saveTokensToCache(id, accessToken, refreshToken); err != nil {
 		return "", ErrUnableToCacheToken
 	}
 
 	return accessToken, nil
 }
 
+func (a *Auth) RefreshToken(accessToken string) (string, error) {
+	token, claims, err := jwtSrv.ValidateAccessToken(accessToken)
+	if err != nil || !token.Valid {
+		return "", ErrInvalidAccessToken
+	}
+
+	id := claims["sub"]
+
+	newAccessToken, _ := jwtSrv.CreateAccessToken(id.(string))
+	newRefreshToken, _ := jwtSrv.CreateRefreshToken(id.(string))
+	if err = a.saveTokensToCache(id.(string), newAccessToken, newRefreshToken); err != nil {
+		return "", ErrUnableToCacheToken
+	}
+
+	return newAccessToken, nil
+}
+
 func (a *Auth) Register(email, login, passwd string) (string, error) {
 	var id string
 
@@ -71,7 +89,7 @@ func (a *Auth) Register(email, login, passwd string) (string, error) {
 	return id, nil
 }
 
-func (a *Auth) saveTokensToCache(accessToken, refreshToken, id string) error {
+func (a *Auth) saveTokensToCache(id, accessToken, refreshToken string) error {
 	res := a.cache.Set(context.Background(), "auth:access_token:"+id, accessToken, accessTokenExpireTime)
 	if err := res.Err(); err != nil {
 		fmt.Println("failed to save access token in redis: ", err.Error())