public async void Add([FromHeader] string auth, [FromForm] string friend) { string user; if ((user = JwtBuilder.UserJwtToken(auth).Result) == null || !UserStore.Exists(friend).Result || !UserStore.Exists(user).Result) { HttpContext.Response.StatusCode = (int)HttpStatusCode.NotFound; return; } HttpContext.Response.Headers.Add("auth", auth); await UserStore.AddFriend(user, friend); }