asp.net-mvc - 具有定义范围的 .NET ASP.NET MVC 应用程序 Facebook OAuth

Question

创建.NET的最简单方法是什么？ ASP.NET MVC Facebook 申请OAuth有明确的范围吗？

我尝试了很多例子。 OAuthWebSecurity.RegisterClient 不支持添加更多 Facebook 范围。 Facebook application template创建一个 Canvas ，我需要非 Canvas 应用程序。 FacebookScopedClient 不完整，无法使用此修复程序。

你有什么建议？

我也开放 JavaScript/jQuery 解决方案。

Answer 1

可能我来得太晚了，但几天前我遇到了这个问题，我在网上发现了一些糟糕的解决方案。所以我写了自己的解决方案，现在只能发布。

我利用了 DotNetOpenAuth.AspNet.Clients.OAuth2Client 类来完成大部分工作。我只是将其扩展为包括范围和额外的用户数据。

public class FacebookExtendedClient : DotNetOpenAuth.AspNet.Clients.OAuth2Client
{   
    protected FacebookClient facebookClient;
    protected string fields;
    protected string scope;
    protected Func<string, object, string> fieldTransformer;
    protected bool emailAsUsername;
    protected IDictionary<string, string> userData;

    private string[] splittedFields;
    private string[] splittedScope;

    protected const string serviceLoginBaseUrl = "https://www.facebook.com/dialog/oauth";
    protected const string serviceMeBaseUrl = "https://graph.facebook.com/me";
    protected const string serviceAccessTokenBaseUrl = "https://graph.facebook.com/oauth/access_token";

    /// <summary>
    /// Create an instrance of the class.
    /// </summary>
    /// <param name="appId">The App ID of the application used to connect to Facebook service.</param>
    /// <param name="appSecret">The App Secret of the application used to connect to Facebook service.</param>
    /// <param name="fields">
    /// String containing comma separated fields to add to the request.
    /// If empty the request will retrieve the default fields based of the specified scope.
    /// </param>
    /// <param name="fieldTransformer">
    /// Function to be applied to the values retrived from facebook.
    /// If null provided the method will try to cast values from object to string explicitly,
    /// an InvalidCastException will be thrown if the cast will not be possible.
    /// </param>
    /// <param name="scope">
    /// String containing comma separated permissions to add to the request.
    /// If empty the request will have the basic scope.
    /// </param>
    /// <param name="emailAsUsername">Makes the email of the facebook user used as authentication username.</param>
    public FacebookExtendedClient(string appId, string appSecret, string fields = "", Func<string, object, string> fieldTransformer = null, string scope = "", bool emailAsUsername = false)
        : base("facebook")
    {
        if (string.IsNullOrEmpty(appId))
            throw new ArgumentException("The appId argument can not be null or empty.", "appId");
        if (string.IsNullOrEmpty(appSecret))
            throw new ArgumentException("The appSecret argument can not be null or empty.", "appSecret");

        fields = fields.Replace(" ", "");
        scope = scope.Replace(" ", "");
        this.splittedFields = fields.Split(',');
        this.splittedScope = scope.Split(',');

        if (emailAsUsername == true && !this.splittedFields.Contains("email") && !this.splittedScope.Contains("email"))
            throw new ArgumentException("The scope argument must contain the 'email' permission and the 'email' field to allow emailAsUsername to true.", "scope");

        this.facebookClient = new FacebookClient();
        this.facebookClient.AppId = appId;
        this.facebookClient.AppSecret = appSecret;
        this.fields = fields;
        this.fieldTransformer = fieldTransformer;
        this.scope = scope;
        this.emailAsUsername = emailAsUsername;
    }

    public FacebookClient FacebookClient
    {
        get
        {
            return this.facebookClient;
        }
    }

    public IDictionary<string, string> UserData
    {
        get
        {
            return this.userData;
        }
    }

    protected override Uri GetServiceLoginUrl(Uri returnUrl)
    {
        Dictionary<string, object> parameters = new Dictionary<string, object>();
        parameters.Add("redirect_uri", returnUrl.AbsoluteUri);

        if (!string.IsNullOrEmpty(this.scope))
            parameters.Add("scope", this.scope);

        return this.facebookClient.GetLoginUrl(parameters);
    }

    protected override IDictionary<string, string> GetUserData(string accessToken)
    {
        // This method makes the AuthenticationResult's UserName property be the facebook username of the logged user,
        // but if the facebook username is missing the facebook id will be used.
        // If emailAsUsername is true then AuthenticationResult's UserName property is the email retrieved from facebook
        // and the facebook username can be retrieved by the key "fb_username" in this.userData

        FacebookClient facebookClient = new FacebookClient(accessToken);

        var getResult = facebookClient.Get<IDictionary<string, object>>("me", new { fields = this.fields });
        Dictionary<string, string> result = new Dictionary<string, string>();

        if (this.fieldTransformer != null)
        {
            foreach (var pair in getResult)
                result.Add(pair.Key, this.fieldTransformer(pair.Key, pair.Value));
        }
        else
        {
            foreach (var pair in getResult)
            {
                string value = pair.Value.ToString();

                if (value == null)
                    throw new InvalidCastException("Cast not possible for the object associate to the key '" + pair.Key + "'.");

                result.Add(pair.Key, value);
            }
        }

        if (this.splittedFields.Contains("username"))
            result["fb_username"] = result["username"];

        if (this.emailAsUsername)
            result["username"] = result["email"];

        this.userData = result;

        return result;
    }

    protected override string QueryAccessToken(Uri returnUrl, string authorizationCode)
    {
        UriBuilder builder = new UriBuilder(serviceAccessTokenBaseUrl);
        builder.Query = string.Format("client_id={0}&client_secret={1}&redirect_uri={2}&code={3}",
            this.facebookClient.AppId, this.facebookClient.AppSecret, HttpUtility.UrlEncode(Encoding.ASCII.GetBytes(returnUrl.AbsoluteUri)), authorizationCode);

        using (WebClient client = new WebClient())
        {
            string str = client.DownloadString(builder.Uri);

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

            return HttpUtility.ParseQueryString(str)["access_token"];
        }
    }
}

您也可以像这样在 OAuthWebSecurity 中注册它(将 RegisterAuth 方法放在 Application_Start 中，就像在 InternetApplication 模板中一样):

public static class AuthConfig
{
    public static void RegisterAuth()
    {
        configuration.LoadFromAppSettings();

        OAuthWebSecurity.RegisterClient(new FacebookExtendedClient(
            "##YOUR_APP_ID##",
            "##YOUR_APP_SECRET##",
            "id,first_name,last_name,link,username,gender,email,age_range,picture.height(200)",
            new Func<string, object, string>(fieldsTransformer),
            "email"));
    }

    private static string fieldsTransformer(string key, object value)
    {
        switch (key)
        {
            case "picture":
                var data = (value as IDictionary<string, object>)["data"] as IDictionary<string, object>;
                return data["url"].ToString();
            case "age_range":
                var min = (value as IDictionary<string, object>)["min"];
                return min.ToString();
            default:
                return value.ToString();
        }
    }
}

正如您在上面的示例中看到的，fieldsTransformer 方法将获取所选每个字段的键和值，在本例中，它将把 facebook 检索到的图片对象转换为图片的 url。这是一个方便的方法，如果为 Func 参数提供 null，则将保存值对象的 JSON 表示形式。

稍后登录后检索客户端信息，可以这样做:

[Authorize]
public class HomeController : Controller
{
    public ActionResult Index()
    {
        IDictionary<string, string> userData = (OAuthWebSecurity.GetOAuthClientData("facebook").AuthenticationClient as FacebookExtendedClient).UserData;
        string email = userData["email"];

        // If leave null the fieldTransform of the client you can access to complex properties like this:
        JObject picture = JObject.Parse(userData["picture"]);
        string url = (picture["data"] as JObject)["url"].ToString();

        ViewBag.Email = userData["email"];
        ViewBag.PictureUrl = url;
        return View();
    }
}

希望您喜欢这段代码，即使有点晚了! :)