自定义DotnetOpenauth Paypal客户端（密钥不存在）

Question

我设法整合了Facebook，Twitter和Google的预定义提供商。但我需要允许人们通过Paypal登录。我创建了以下继承DotNetOpenAuth.AspNet.Clients.OAuth2Client的类。

using System;
using System.Collections.Generic;
using System.Diagnostics.CodeAnalysis;
using System.Net;
using System.Web;
using Validation;

using DotNetOpenAuth.AspNet;
using DotNetOpenAuth.Messaging;
using Newtonsoft.Json;
using System.Text.RegularExpressions;

namespace OauthClient
{
    public class PayPalProviderClient : DotNetOpenAuth.AspNet.Clients.OAuth2Client
    {
        #region Oauth2
        #region Constants and Fields

        // https://www.x.com/developers/paypal/documentation-tools/quick-start-guides/oauth-openid-connect-integration-paypal#making-first-call-register
        // 3 https://www.paypal.com/webapps/auth/protocol/openidconnect/v1/authorize?client_id=<your_app_id>&response_type=code&scope=openid&redirect_uri=https://www.example.com/my-redirect-uri
        // 5 https://your-return-url?code=auth-code&scope=space-separted-scope-list&state=state
        // 6 https://www.paypal.com/webapps/auth/protocol/openidconnect/v1/tokenservice

        private const string AuthorizationEndpoint = "https://www.paypal.com/webapps/auth/protocol/openidconnect/v1/authorize?response_type=code&scope=openid&";
        private const string TokenEndpoint = "https://www.paypal.com/webapps/auth/protocol/openidconnect/v1/tokenservice";
        private const string UserDetailsEndPoint = "https://www.paypal.com/webapps/auth/protocol/openidconnect/v1/userinfo";

        private readonly string appId;
        private readonly string appSecret;


        #endregion

        #region Constructors and Destructors

        public PayPalProviderClient(string appId, string appSecret) : base("paypal")
        {
            Requires.NotNullOrEmpty(appId, "appId");
            Requires.NotNullOrEmpty(appSecret, "appSecret");
            this.appId = appId;
            this.appSecret = appSecret;
        }

        #endregion

        protected override Uri GetServiceLoginUrl(Uri returnUrl)
        {
            var builder = new UriBuilder(AuthorizationEndpoint);
            builder.AppendQueryArgument("client_id", this.appId);
            builder.AppendQueryArgument("redirect_uri", returnUrl.AbsoluteUri);
            return builder.Uri;
        }

        protected override IDictionary<string, string> GetUserData(string accessToken)
        {
            var builder = new UriBuilder(UserDetailsEndPoint);
            builder.AppendQueryArgument("schema", "openid");
            builder.AppendQueryArgument("access_token", accessToken);

            Dictionary<string, string> userData = new Dictionary<string, string>();
            using (WebClient client = new WebClient())
            {
                string data = client.DownloadString(builder.Uri);
                if (string.IsNullOrEmpty(data))
                    return null;
                else
                    userData = JsonConvert.DeserializeObject<Dictionary<string, string>>(data);
            }
            return userData;
        }

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

        private IDictionary<string, string> GetUserData(string accessCode, Uri redirectURI)
        {
            string token = QueryAccessToken(redirectURI, accessCode);
            if (token == null || token == "")
                return null;
            return GetUserData(token);
        }

        private string QueryAccessToken(string returnUrl, string authorizationCode)
        {
            return QueryAccessToken(new Uri(returnUrl), authorizationCode);
        }

        protected override string QueryAccessToken(Uri returnUrl, string authorizationCode)
        {
            var builder = new UriBuilder(TokenEndpoint);
            //"client_id=<your_app_id>&client_secret=<your_app_secret>&grant_type=authorization_code&code=<code>&redirect_uri=<urlencoded_return_url>"
            builder.AppendQueryArgument("client_id", this.appId);
            builder.AppendQueryArgument("client_secret", this.appSecret);
            builder.AppendQueryArgument("grant_type", "authorization_code");
            builder.AppendQueryArgument("code", authorizationCode);
            builder.AppendQueryArgument("redirect_uri", returnUrl.AbsoluteUri);

            using (WebClient client = new WebClient())
            {
                string data = client.DownloadString(builder.Uri);
                if (string.IsNullOrEmpty(data))
                    return null;

                Dictionary<string, string> userData = JsonConvert.DeserializeObject<Dictionary<string, string>>(data);
                if (userData.ContainsKey("access_token"))
                    return userData["access_token"].ToString();
                else
                    return string.Empty;
            }
        }

        private string RefreshAccessToken(Uri returnUrl, string authorizationCode)
        {
            var builder = new UriBuilder(TokenEndpoint);
            builder.AppendQueryArgument("client_id", this.appId);
            builder.AppendQueryArgument("client_secret", this.appSecret);
            builder.AppendQueryArgument("grant_type", "refresh_token");
            builder.AppendQueryArgument("code", authorizationCode);
            builder.AppendQueryArgument("redirect_uri", returnUrl.AbsoluteUri);

            using (WebClient client = new WebClient())
            {
                string data = client.DownloadString(builder.Uri);
                if (string.IsNullOrEmpty(data))
                    return null;

                Dictionary<string, string> userData = JsonConvert.DeserializeObject<Dictionary<string, string>>(data);
                if (userData.ContainsKey("access_token"))
                    return userData["access_token"].ToString();
                else
                    return string.Empty;
            }
        }
        #endregion
    }
}

这是我的控制器调用的

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

导致“System.Collections.Generic.KeyNotFoundException未被用户代码处理” - 字典中没有给定的密钥。

有没有人有一个使用DNOA和PayPal的工作示例？或者知道为什么我得到这个例外/我错过了什么钥匙？

更新

我设法获得了一个正常工作的版本，请参阅下面的代码：

using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.IO;
using System.Net;
using System.Web;
using DotNetOpenAuth.AspNet;
using DotNetOpenAuth.AspNet.Clients;
using DotNetOpenAuth.Messaging;
using Newtonsoft.Json;

namespace OauthClients
{

    /// <summary>
    /// A DotNetOpenAuth client for logging in to paypal using OAuth2.
    /// Reference: https://developers.paypal.com/accounts/docs/OAuth2
    /// </summary>
    public class PaypalOAuth2Client : OAuth2Client
    {
        #region Constants and Fields

        /// <summary>
        /// The authorization endpoint.
        /// </summary>
        private const string AuthorizationEndpoint = "https://www.paypal.com/webapps/auth/protocol/openidconnect/v1/authorize?response_type=code&scope=openid&";

        /// <summary>
        /// The token endpoint.
        /// </summary>
        private const string TokenEndpoint = "https://www.paypal.com/webapps/auth/protocol/openidconnect/v1/tokenservice";

        /// <summary>
        /// The user info endpoint.
        /// </summary>
        private const string UserDetailsEndPoint = "https://www.paypal.com/webapps/auth/protocol/openidconnect/v1/userinfo";

        /// <summary>
        /// The base uri for scopes.
        /// </summary>
        private const string ScopeBaseUri = "https://www.paypal.com/webapps/auth/";

        /// <summary>
        /// The _app id.
        /// </summary>
        private readonly string _clientId;

        /// <summary>
        /// The _app secret.
        /// </summary>
        private readonly string _clientSecret;

        /// <summary>
        /// The requested scopes.
        /// </summary>
        private readonly string[] _requestedScopes;

        #endregion


        /// <summary>
        /// Creates a new paypal OAuth2 client.
        /// </summary>
        /// <param name="clientId">The paypal Client Id</param>
        /// <param name="clientSecret">The paypal Client Secret</param>
        /// <param name="requestedScopes">One or more requested scopes, passed without the base URI.</param>
        public PaypalOAuth2Client(string clientId, string clientSecret): base("paypal")
        {
            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)
        {
            var builder = new UriBuilder(AuthorizationEndpoint);
            builder.AppendQueryArgument("client_id", this._clientId);
            builder.AppendQueryArgument("redirect_uri", returnUrl.AbsoluteUri);

            return builder.Uri;
        }

        protected override IDictionary<string, string> GetUserData(string accessToken)
        {
            var request = WebRequest.Create(UserDetailsEndPoint + "?schema=openid&access_token=" + accessToken);
            Dictionary<string, string> authData;

            using (var response = request.GetResponse())
            using (var responseStream = response.GetResponseStream())
            using (var streamReader = new StreamReader(responseStream))
            {
                authData = JsonConvert.DeserializeObject<Dictionary<string, string>>(streamReader.ReadToEnd());
                return authData;
            }
        }

        protected override string QueryAccessToken(Uri returnUrl, string authorizationCode)
        {
            var builder = new UriBuilder(TokenEndpoint);

            builder.AppendQueryArgument("client_id", this._clientId);
            builder.AppendQueryArgument("client_secret", this._clientSecret);
            builder.AppendQueryArgument("grant_type", "authorization_code");
            builder.AppendQueryArgument("code", authorizationCode);
            builder.AppendQueryArgument("redirect_uri", returnUrl.AbsoluteUri);


            using (WebClient client = new WebClient())
            {
                var data = client.DownloadString(builder.Uri);

                if (string.IsNullOrEmpty(data))
                    return null;

                Dictionary<string, string> userData = JsonConvert.DeserializeObject<Dictionary<string, string>>(data);
                if (userData.ContainsKey("access_token"))
                    return userData["access_token"].ToString();
                else
                    return null;
            }
        }

        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["user_id"];
            string name = string.Empty ;

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

Answer 1

您必须在方法GetUserData中提供带键=“id”的词典条目（名称为“name”和“username”的词典键都可以）。

来自OAuth2Client.class的

代码 ... string id = userData [“id”];             字符串名称;

        // Some oAuth providers do not return value for the 'username' attribute. 
        // In that case, try the 'name' attribute. If it's still unavailable, fall back to 'id'
        if (!userData.TryGetValue("username", out name) && !userData.TryGetValue("name", out name)) {
            name = id;
        }

...

如您所见，如果缺少其中一个密钥，代码将会失败。