我正在使用 ASP.NET MVC 5 和 OWIN。

我做了很多研究，还没有找到如何使用刷新 token 更新访问 token 。

我的场景是:用户第一次访问我的应用程序时，他或她授予访问我读取从 API 返回的刷新 token 的帐户的权限。当用户返回我的应用程序时，我需要根据“刷新 token ”刷新访问 token 。

谁能提供一些代码？

这是我到目前为止所取得的成就:

Startup.Auth.cs:

    var googleOAuth2AuthenticationOptions = new GoogleOAuth2AuthenticationOptions
    {
        Caption = "Google+",
        ClientId = Parameters.Instance.Authentication.oAuth.GooglePlus.ClientId,
        ClientSecret = Parameters.Instance.Authentication.oAuth.GooglePlus.ClientSecret,
        CallbackPath = new PathString("/oauth-login-return"),
        Provider = new GoogleOAuth2AuthenticationProvider
        {
            OnAuthenticated = async context =>
            {
                context.Identity.AddClaim(new Claim(ClaimTypes.Name, context.Identity.FindFirstValue(ClaimTypes.Name)));
                context.Identity.AddClaim(new Claim(ClaimTypes.Email, context.Identity.FindFirstValue(ClaimTypes.Email)));
                context.Identity.AddClaim(new Claim("picture", context.User.GetValue("picture").ToString()));
                context.Identity.AddClaim(new Claim("profile", context.User.GetValue("profile").ToString()));
                context.Identity.AddClaim(
                    new Claim(Parameters.Instance.Authentication.oAuth.GooglePlus.AccessTokenClaimType,
                        context.AccessToken));
            }
        }
    };
    googleOAuth2AuthenticationOptions.Scope.Add("https://www.googleapis.com/auth/plus.login");
    googleOAuth2AuthenticationOptions.Scope.Add("https://www.googleapis.com/auth/userinfo.email");

身份验证 Controller :

[HttpPost]
[AllowAnonymous]
public ActionResult ExternalLogin(string provider, string returnUrl)
{
    RedirectIfAuthenticated();

    return new ChallengeResult(provider, Url.Content("~/oauth-login-callback"));
}

[ActionName("oauth-login-back")]
public async Task<ActionResult> ExternalLoginCallback(string returnUrl)
{
}

// Used for XSRF protection when adding external logins
private const string XsrfKey = "XsrfId";

private IAuthenticationManager AuthenticationManager
{
    get
    {
        return HttpContext.GetOwinContext().Authentication;
    }
}

private class ChallengeResult : HttpUnauthorizedResult
{
    public ChallengeResult(string provider, string redirectUri)
        : this(provider, redirectUri, null)
    {
    }

    private ChallengeResult(string provider, string redirectUri, string userId)
    {
        LoginProvider = provider;
        RedirectUri = redirectUri;
        UserId = userId;
    }

    private string LoginProvider { get; set; }

    private string RedirectUri { get; set; }

    private string UserId { get; set; }

    public override void ExecuteResult(ControllerContext context)
    {
        var properties = new AuthenticationProperties { RedirectUri = RedirectUri };
        if (UserId != null)
        {
            properties.Dictionary[XsrfKey] = UserId;
        }
        context.HttpContext.GetOwinContext().Authentication.Challenge(properties, LoginProvider);
    }
}

最佳答案

这个问题根本不是重复的。我希望这能帮助其他人不要像我一样度过几天。

将近 4 天后，我发现了如何使用 OWIN 在 google api 中获取新的访问 token 。

我将发布解决方案，但首先，我必须说，帮助我开始了解我的错误的是为 Katana 项目设置调试符号。请参阅此链接: http://www.symbolsource.org/Public/Home/VisualStudio

此图展示了如何配置调试符号服务器。

这一个显示了正在加载的 Katana 调试符号。

之后，我发现我的问题是 Google API 返回 403: Forbidden

“访问未配置。请使用 Google Developers Console 为您的项目激活 API”

然后，在stack overflow上发现了这篇帖子: "Access Not Configured. Please use Google Developers Console to activate the API for your project."

更具体地说，这个答案:https://stackoverflow.com/a/24401189/833846

之后，我转到 Google Developers Console 并设置 Google+ API

然后，瞧!它奏效了。

现在，使用刷新 token 获取新访问 token 的代码(我还没有找到使用 OWIN API 完成此操作的任何方法)。

public static class TokenValidator
{
    /// <summary>
    /// Obtém um novo access token na API do google.
    /// </summary>
    /// <param name="clientId"></param>
    /// <param name="clientSecret"></param>
    /// <param name="refreshToken"></param>
    /// <returns></returns>
    public static GoogleRefreshTokenModel ValidateGoogleToken(string clientId, string clientSecret, string refreshToken)
    {
        const string url = "https://accounts.google.com/o/oauth2/token";

        var parameters = new List<KeyValuePair<string, string>>
        {
            new KeyValuePair<string, string>("client_id", clientId),
            new KeyValuePair<string, string>("client_secret", clientSecret),
            new KeyValuePair<string, string>("grant_type", "refresh_token"),
            new KeyValuePair<string, string>("refresh_token", refreshToken)
        };

        var content = GetContentAsync(url, "POST",  parameters);

        var token = JsonConvert.DeserializeObject<GoogleRefreshTokenModel>(content);

        return token;
    }

    private static string GetContentAsync(string url, 
        string method = "POST",
        IEnumerable<KeyValuePair<string, string>> parameters = null)
    {
        return method == "POST" ? PostAsync(url, parameters) : GetAsync(url, parameters);
    }

    private static string PostAsync(string url, IEnumerable<KeyValuePair<string, string>> parameters = null)
    {
        var uri = new Uri(url);

        var request = WebRequest.Create(uri) as HttpWebRequest;
        request.Method = "POST";
        request.KeepAlive = true;
        request.ContentType = "application/x-www-form-urlencoded";

        var postParameters = GetPostParameters(parameters);

        var bs = Encoding.UTF8.GetBytes(postParameters);
        using (var reqStream = request.GetRequestStream())
        {
            reqStream.Write(bs, 0, bs.Length);
        }

        using (var response = request.GetResponse())
        {
            var sr = new StreamReader(response.GetResponseStream());
            var jsonResponse = sr.ReadToEnd();
            sr.Close();

            return jsonResponse;
        }
    }

    private static string GetPostParameters(IEnumerable<KeyValuePair<string, string>> parameters = null)
    {
        var postParameters = string.Empty;
        foreach (var parameter in parameters)
        {
            postParameters += string.Format("&{0}={1}", parameter.Key,
                HttpUtility.HtmlEncode(parameter.Value));
        }
        postParameters = postParameters.Substring(1);

        return postParameters;
    }

    private static string GetAsync(string url, IEnumerable<KeyValuePair<string, string>> parameters = null)
    {
        url += "?" + GetQueryStringParameters(parameters);

        var forIdsWebRequest = WebRequest.Create(url);
        using (var response = (HttpWebResponse)forIdsWebRequest.GetResponse())
        {
            using (var data = response.GetResponseStream())
            using (var reader = new StreamReader(data))
            {
                var jsonResponse = reader.ReadToEnd();

                return jsonResponse;
            }
        }
    }

    private static string GetQueryStringParameters(IEnumerable<KeyValuePair<string, string>> parameters = null)
    {
        var queryStringParameters = string.Empty;
        foreach (var parameter in parameters)
        {
            queryStringParameters += string.Format("&{0}={1}", parameter.Key,
                HttpUtility.HtmlEncode(parameter.Value));
        }
        queryStringParameters = queryStringParameters.Substring(1);

        return queryStringParameters;
    }
}

重要提示 1:要获得刷新 token ，您必须在“ExecuteResult”方法中将“access_type”设置为“offline”，方法如下:

properties.Dictionary["access_type"] = "offline";

重要提示 2:获得刷新 token 后，您必须将其存储在某个安全来源中。 Google API 不会向您发出新的刷新 token ，除非您在调用该行之前将“approval_prompt”设置为“force”(以相同的方法):

context.HttpContext.GetOwinContext().Authentication.Challenge(properties, LoginProvider);

我还建议您看看:

Google API Offline Access

Google OAUTH 2.0 Playground

Google API Discovery Check

关于c# - 如何使用刷新 token 更新访问 token ？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/24894789/