public async Task <List <string> > All([FromHeader] string auth) { string user; if ((user = JwtBuilder.UserJwtToken(auth).Result) == null || !UserStore.Exists(user).Result) { HttpContext.Response.StatusCode = (int)HttpStatusCode.Unauthorized; return(null); } HttpContext.Response.Headers.Add("auth", auth); return(await ProductStore.Categories()); }