Asp.net 如何让用户使用SoundCloud登录到我的站点

我想让用户通过SoundCloud对我的ASP.NET MVC 4项目进行身份验证。由于没有.NET SDK，我编写了一个自定义的

OAuth2Client

来处理身份验证。在将客户端添加到my

AuthConfig.cs

之后，它适当地显示为一个登录选项。问题是，当我点击按钮登录时，它总是返回

Login Failure.

Unsuccessful login with service.

甚至不要求我登录SoundCloud。有什么问题？我为GitHub实现了一个非常类似的客户端，它工作起来没有问题

这是我的客户：

 public class SoundCloudOAuth2Client : OAuth2Client
 {
     private const string ENDUSERAUTHLINK = "https://soundcloud.com/connect";
     private const string TOKENLINK = "https://api.soundcloud.com/oauth2/token";
     private readonly string _clientID;
     private readonly string _clientSecret;

     public SoundCloudOAuth2Client(string clientID, string clientSecret) : base("SoundCloud")
     {
         if (string.IsNullOrWhiteSpace(clientID)) {
                throw new ArgumentNullException("clientID");
         }

         if (string.IsNullOrWhiteSpace(clientSecret)) {
                throw new ArgumentNullException("clientSecret");
         }

         _clientID = clientID;
         _clientSecret = clientSecret;
     }

     protected override Uri GetServiceLoginUrl(Uri returnUrl)
     {
         StringBuilder serviceUrl = new StringBuilder();
         serviceUrl.Append(ENDUSERAUTHLINK);
         serviceUrl.AppendFormat("?client_id={0}", _clientID);
         serviceUrl.AppendFormat("&response_type={0}", "code");
         serviceUrl.AppendFormat("&scope={0}", "non-expiring");
         serviceUrl.AppendFormat("&redirect_uri={0}", System.Uri.EscapeDataString(returnUrl.ToString()));

         return new Uri(serviceUrl.ToString());
     }

     public override void RequestAuthentication(HttpContextBase context, Uri returnUrl)
     {
         base.RequestAuthentication(context, returnUrl);
     }

     protected override IDictionary<string, string> GetUserData(string accessToken)
     {
         IDictionary<String, String> extraData = new Dictionary<String, String>();

         var webRequest = (HttpWebRequest)WebRequest.Create("https://api.soundcloud.com/me.json?oauth_token=" + accessToken);
         webRequest.Method = "GET";
         string response = "";
         using (HttpWebResponse webResponse = HttpWebResponse)webRequest.GetResponse())
         {
             using (StreamReader reader = new StreamReader(webResponse.GetResponseStream()))
             {
                 response = reader.ReadToEnd();
             }
         }

         var json = JObject.Parse(response);
         string id = (string)json["id"];
         string username = (string)json["username"];
         string permalinkUrl = (string)json["permalink_url"];

         extraData = new Dictionary<String, String>
         {
             {"SCAccessToken", accessToken},
             {"username", username}, 
             {"permalinkUrl", permalinkUrl}, 
             {"id", id}                                           
         };

         return extraData;
     }

     protected override string QueryAccessToken(Uri returnUrl, string authorizationCode)
     {
         StringBuilder postData = new StringBuilder();
         postData.AppendFormat("client_id={0}", this._clientID);
         postData.AppendFormat("&redirect_uri={0}", HttpUtility.UrlEncode(returnUrl.ToString()));
         postData.AppendFormat("&client_secret={0}", this._clientSecret);
         postData.AppendFormat("&grant_type={0}", "authorization_code");
         postData.AppendFormat("&code={0}", authorizationCode);

         string response = "";
         string accessToken = "";

         var webRequest = (HttpWebRequest)WebRequest.Create(TOKENLINK);    
         webRequest.Method = "POST";
         webRequest.ContentType = "application/x-www-form-urlencoded";

         using (Stream s = webRequest.GetRequestStream())
         {
             using (StreamWriter sw = new StreamWriter(s))
                    sw.Write(postData.ToString());
         }

         using (WebResponse webResponse = webRequest.GetResponse())
         {
             using (StreamReader reader = new StreamReader(webResponse.GetResponseStream()))
             {
                 response = reader.ReadToEnd();
             }
         }

         var json = JObject.Parse(response);
         accessToken = (string)json["access_token"];

         return accessToken;
     }

     public override AuthenticationResult VerifyAuthentication(HttpContextBase context, Uri returnPageUrl)
     {    
         string code = context.Request.QueryString["code"];  
         string u = context.Request.Url.ToString();

         if (string.IsNullOrEmpty(code))
         {
             return AuthenticationResult.Failed;
         }

         string accessToken = this.QueryAccessToken(returnPageUrl, code);
         if (accessToken == null)
         {
             return AuthenticationResult.Failed;
         }

         IDictionary<string, string> userData = this.GetUserData(accessToken);
         if (userData == null)
         {
             return AuthenticationResult.Failed;
         }

         string id = userData["id"];
         string name;

         if (!userData.TryGetValue("username", out name) && !userData.TryGetValue("name", out name))
         {
             name = id;
         }

         return new AuthenticationResult(
             isSuccessful: true, provider: "SoundCloud", providerUserId: id, userName: name, extraData: userData);
     }
 }

---

有多个问题需要解决，从运行的第一个函数开始：

GetServiceLoginUrl（Uri returnUrl）

自动创建的

returnUrl

，包含SoundCloud不喜欢的符号。您需要去掉符号，并确保SoundCloud帐户中的“用于身份验证的重定向URI”与发送的内容（querystring和all）完全匹配。以下是默认情况下作为returnURL发送的内容的示例：

https://localhost:44301/Account/ExternalLoginCallback?__provider__=SoundCloud&__sid__=blahblahyoursid

第一步是删除

和\uuuu sid\uuu

值。您可以去掉

sid

值并将其作为

state

参数传递，以备需要。新函数如下所示：

protected override Uri GetServiceLoginUrl(Uri returnUrl)
{
    StringBuilder serviceUrl = new StringBuilder();
    string sid = String.Empty;
    if (returnUrl.ToString().Contains("__sid__"))
    {
        int index = returnUrl.ToString().IndexOf("__sid__") + 8;
        int len = returnUrl.ToString().Length;
        sid = returnUrl.ToString().Substring(index, len - index-1);
    }

    string redirectUri = returnUrl.ToString().Contains('&') ? 
    returnUrl.ToString().Substring(0,returnUrl.ToString().IndexOf("&")) : 
    returnUrl.ToString();
    serviceUrl.Append(ENDUSERAUTHLINK);
    serviceUrl.AppendFormat("?client_id={0}", _clientID);
    serviceUrl.AppendFormat("&response_type={0}", "code");
    serviceUrl.AppendFormat("&scope={0}", "non-expiring");
    serviceUrl.AppendFormat("&state={0}", sid);
    serviceUrl.AppendFormat("&redirect_uri={0}", System.Uri.EscapeDataString(redirectUri));

    return new Uri(serviceUrl.ToString());
}

这解决了部分问题。SoundlCloud中的重定向URI现在只是

https://localhost:44301/Account/ExternalLoginCallback?__provider__=SoundCloud

）。但尝试验证仍将返回

false

。下一个要解决的问题是

AccountController.cs

，具体来说：

[AllowAnonymous]
public ActionResult ExternalLoginCallback(string returnUrl)

因为在第一行中，它试图返回：

AuthenticationResult result = OAuthWebSecurity.VerifyAuthentication(Url.Action("ExternalLoginCallback", new { ReturnUrl = returnUrl }));

这不适用于我的自定义

OAuth2Client

，因为

VerifyAuthentication

采用不同的参数。通过检测是否为SoundCloud客户端，然后使用自定义VerifyAuthentication进行修复：

[AllowAnonymous]
public ActionResult ExternalLoginCallback(string returnUrl)
{
    AuthenticationResult result;
    var context = this.HttpContext;
    string p = Tools.GetProviderNameFromQueryString(context.Request.QueryString);

    if (!String.IsNullOrEmpty(p) && p.ToLower() == "soundcloud")
    {
        result = new SoundCloudOAuth2Client(
                clientID: MyValues.SCCLIENTID,
                clientSecret: MyValues.SCCLIENTSECRET).VerifyAuthentication(this.HttpContext, new Uri(String.Format("{0}/Account/ExternalLoginCallback?__provider__=SoundCloud", context.Request.Url.GetLeftPart(UriPartial.Authority).ToString())));
    }
    else
    {
        result = OAuthWebSecurity.VerifyAuthentication(Url.Action("ExternalLoginCallback", new { ReturnUrl = returnUrl }));
    }

在哪里

public static string GetProviderNameFromQueryString(NameValueCollection queryString)
{
    var result = queryString["__provider__"];
    ///commented out stuff
    return result;
}

---

之后，一切正常，您可以成功地进行身份验证。您可以配置

GetUserData

以获取您想要保存的任何SoundCloud数据，然后将其保存到您的UserProfile或相关表中。关键是

SCAccessToken

，因为这是您将来上传到他们帐户所需的。

您知道如何使用Owin进行SoundCloud身份验证吗？@gldraphael No，抱歉。我最近对Sound Cloud auth的所有使用都在node.js中。尽管我认为（希望）自从我写了这篇文章之后，会有一个关于nuget之类的软件包。

public static string GetProviderNameFromQueryString(NameValueCollection queryString)
{
    var result = queryString["__provider__"];
    ///commented out stuff
    return result;
}