OpenTween.Api.MicrosoftTranslatorApi.UpdateAccessTokenIfExpired C# (CSharp) Method

        public async Task UpdateAccessTokenIfExpired()
        {
            if (this.AccessToken != null && this.RefreshAccessTokenAt > DateTime.Now)
                return;

            var accessToken = await this.GetAccessTokenAsync()
                .ConfigureAwait(false);

            this.AccessToken = accessToken.Item1;

            // expires_in の示す時刻より 30 秒早めに再発行する
            this.RefreshAccessTokenAt = DateTime.Now + accessToken.Item2 - TimeSpan.FromSeconds(30);
        }