如何通過Oauth2身份驗證使用Google Contacts API

Question

我在下面的代碼中使用使用OAuth2的Google Calendar API（ https://developers.google.com/google-apps/calendar/ ）獲取日歷條目。 它運作良好。

private IList<string> scopes = new List<string>();
private CalendarService calendarService;

private void InitializeCalendarService()
{
        // Add the calendar specific scope to the scopes list
        scopes.Add(CalendarService.Scopes.Calendar.GetStringValue());

        // Display the header and initialize the sample
        CommandLine.EnableExceptionHandling();
        CommandLine.DisplayGoogleSampleHeader("Google.Api.Calendar.v3 Sample");

        // Create the authenticator
        //FullClientCredentials credentials = PromptingClientCredentials.EnsureFullClientCredentials();
        var provider = new NativeApplicationClient(GoogleAuthenticationServer.Description);

        FullClientCredentials credentials = new FullClientCredentials();
        credentials.ClientId = "XYZ.apps.googleusercontent.com";
        credentials.ClientSecret = "XYZ";
        credentials.ApiKey = "XYZ";

        provider.ClientIdentifier = credentials.ClientId;
        provider.ClientSecret = credentials.ClientSecret;
        OAuth2Authenticator<NativeApplicationClient> auth = new OAuth2Authenticator<NativeApplicationClient>(provider, GetAuthorization);

        // Create the calendar service using an initializer instance
        BaseClientService.Initializer initializer = new BaseClientService.Initializer();
        initializer.Authenticator = auth;
        calendarService = new CalendarService(initializer);

        CalendarList list = calendarService.CalendarList.List().Execute();
        // do something with the list .. the list is all good

} 

public IAuthorizationState GetAuthorization(NativeApplicationClient client)
{
        // You should use a more secure way of storing the key here as
        // .NET applications can be disassembled using a reflection tool.
        const string STORAGE = "google.samples.dotnet.calendar";
        const string KEY = "s0mekey";

        // Check if there is a cached refresh token available.
        IAuthorizationState state = AuthorizationMgr.GetCachedRefreshToken(STORAGE, KEY);
        if ((state != null))
        {
            try
            {
                client.RefreshToken(state);
                return state;
                // we are done
            }
            catch (DotNetOpenAuth.Messaging.ProtocolException ex)
            {
                CommandLine.WriteError("Using an existing refresh token failed: " + ex.Message);
                CommandLine.WriteLine();
            }
        }

        // Retrieve the authorization from the user
        string[] array = new string[scopes.Count];
        scopes.CopyTo(array,0);
        state = AuthorizationMgr.RequestNativeAuthorization(client, array);
        AuthorizationMgr.SetCachedRefreshToken(STORAGE, KEY, state);
        return state;
} 

如何使用類似的OAuth2Authenticator來獲取聯系人？

我可以使用下面的代碼獲取聯系人，但它不是密碼，我需要使用Oath2使其工作。 以下示例使用Gdata聯系人api v2。 我可以看到我可以通過OAuth2Authenticator，但我不確定如何正確地做到這一點（我無法在谷歌網站上看到C＃中的任何有效示例）並根據用戶選擇的內容獲取訪問代碼。 我無法看到如何將OAuth2Authenticator與聯系人api v3一起使用（ https://developers.google.com/google-apps/contacts/v3/ ）

RequestSettings rsLoginInfo = new RequestSettings("", email,pwd);
rsLoginInfo.AutoPaging = true;
ContactsRequest cRequest = new ContactsRequest(rsLoginInfo);

// fetch contacts list
Feed<Contact> feedContacts = cRequest.GetContacts();
foreach (Contact gmailAddresses in feedContacts.Entries)
{
        // Looping to read  email addresses
        foreach (EMail emailId in gmailAddresses.Emails)
        {
           lstContacts.Add(emailId.Address);
        }
}

Answer 1

我最后通過在用戶選擇Google帳戶並授予訪問權限時讓瀏覽器控件讀取文檔標題值來獲取訪問代碼。

例如：

生成URL

RedirectURI = "urn:ietf:wg:oauth:2.0:oob"

OAuth2Parameters parameters = new OAuth2Parameters()
{
    ClientId = clientId,
    ClientSecret = clientSecret,
    RedirectUri = redirectUri,
    Scope = requiredScope
};


// Request authorization from the user (by opening a browser window):
string url = OAuthUtil.CreateOAuth2AuthorizationUrl(parameters);
var loginUri = new Uri(url);

// This form has browser control
GoogleLoginForm form = new GoogleLoginForm(loginUri, redirectUri);
var dr = form.ShowDialog();

if (dr == System.Windows.Forms.DialogResult.OK)
{
    parameters.AccessCode = form.OAuthVerifierToken;
}

然后在GoogleLoginForm中：我們有一個瀏覽器控件並注冊了browserControl_Navigated事件並執行以下操作。 DocumentTitle包含用於生成令牌的AccessCode。

private void GoogleLoginForm_Load(object sender, EventArgs e)
{
   wbGoogleLogin.Url = _loginUri;
}

private void wbGoogleLogin_Navigated(object sender, WebBrowserNavigatedEventArgs e)
{
    string fullPath = e.Url.ToString();
    WebBrowser control = sender as WebBrowser;
    if (control != null &&  !string.IsNullOrEmpty(control.DocumentTitle) && control.DocumentTitle.Contains("Success code"))
    {
       _OAuthVerifierToken = control.DocumentTitle.Replace("Success code=","");
       DialogResult = DialogResult.OK;
    }
}

這樣就可以在同一段代碼中完成，而無需編寫某種復雜的回調服務來將訪問令牌讀回到我們的系統中。

不完全確定為什么日歷api內置了這個，而聯系人API沒有。

Answer 2

首先，快速回答您的問題。 我相信IAuthorizationState具有與OAuth2Parameters類似的屬性。 因此，您應該能夠這樣做（將它與您對日歷的代碼結合起來）：

OAuth2Authenticator<NativeApplicationClient> auth = new OAuth2Authenticator<NativeApplicationClient>(provider, GetAuthorization);

//This will call your GetAuthorization method
auth.LoadAccessToken()
RequestSettings settings = new RequestSettings("appName", auth.State.AccessToken);
ContactsRequest cRequest = new ContactsRequest(settings);

// fetch contacts list
Feed<Contact> feedContacts = cRequest.GetContacts();
foreach (Contact gmailAddresses in feedContacts.Entries)
{
        // Looping to read  email addresses
        foreach (EMail emailId in gmailAddresses.Emails)
        {
           lstContacts.Add(emailId.Address);
        }
}

這應該起作用，因為RequestSettings允許您指定訪問令牌。 話雖這么說，我自己更喜歡使用：

var parameters = new OAuth2Parameters()
{
    //Client 
    ClientId = CLIENT_ID,
    ClientSecret = CLIENT_SECRET,
    RedirectUri = redirectUri,
    Scope = "https://www.google.com/m8/feeds",
    ResponseType = "code"
};

//User clicks this auth url and will then be sent to your redirect url with a code parameter
var authorizationUrl = OAuthUtil.CreateOAuth2AuthorizationUrl(parameters);
.
.
.
//using the code parameter
parameters.AccessCode = code;
OAuthUtil.GetAccessToken(parameters);
var settings = new RequestSettings(applicationName, parameters);
var cr = new ContactsRequest(settings);
//Now you can use contacts as you would have before

雖然，我只使用Web服務器應用程序對此進行了測試，因此您的情況可能需要驗證器嗎？ 我發現這些源代碼很方便：

OAuth2Demo

IAuthorizationState

OAuth2Authenticator