我正在尝试使用Xamarin.Auth和Xamarin Google-APIs登录Google并访问云端硬盘。我已经设法使几乎所有工作,但身份验证令牌似乎在大约一个小时后到期。一切都运行良好一段时间,但大约一个小时后,当我尝试访问时,我收到一个无效的凭据[401]错误和泄漏:
Google.Apis.Requests.RequestError
Invalid Credentials [401]
Errors [
Message[Invalid Credentials] Location[Authorization - header] Reason[authError] Domain[global]
]
: GoogleDriveAgent: FetchRemoteFileList() Failed! with Exception: {0}
[0:] Google.Apis.Requests.RequestError
Invalid Credentials [401]
Errors [
Message[Invalid Credentials] Location[Authorization - header] Reason[authError] Domain[global]
]
: GoogleDriveAgent: FetchRemoteFileList() Failed! with Exception: {0}
objc[37488]: Object 0x7f1530c0 of class __NSDate autoreleased with no pool in place - just leaking - break on objc_autoreleaseNoPool() to debug
objc[37488]: Object 0x7f151e50 of class __NSCFString autoreleased with no pool in place - just leaking - break on objc_autoreleaseNoPool() to debug
//...more leaks.
我想确保我按预期使用Xamarin.Auth和Google API,所以这是我的代码:
在我的GoogleDriveService课程中,我有一个帐户商店和一个已保存的帐户:
AccountStore Store {
get {
if (m_store == null)
m_store = AccountStore.Create ();
return m_store;
}
}
Account SavedAccount {
get {
var savedAccounts = Store.FindAccountsForService ("google");
m_savedAccount = (savedAccounts as List<Account>).Count > 0 ? (savedAccounts as List<Account>) [0] : null;
return m_savedAccount;
}
}
我初始化会话并启动服务:
void InitializeSession ()
{
Authenticator = new GoogleAuthenticator (ClientID, new Uri (RedirectUrl), GoogleDriveScope);
Authenticator.Completed += HandleAuthenticationCompletedEvents;
if (SavedAccount != null) {
Authenticator.Account = SavedAccount;
StartService ();
}
UpdateSignInStatus ();
}
bool StartService ()
{
try {
Service = new DriveService (Authenticator);
return true;
} catch (Exception ex) {
// Log exception
return false;
}
}
...并回复认证已完成的事件:
void HandleAuthenticationCompletedEvents (object sender, AuthenticatorCompletedEventArgs e)
{
if (e.IsAuthenticated) { // Success
UpdateSignInStatus();
Store.Save (e.Account, "google");
Authenticator.Account = e.Account;
StartService();
LoginController.DismissViewController(true, null);
} else { // Cancelled or no success
UpdateSignInStatus();
LoginController.DismissViewController(true, null);
LoginController = null;
InitializeSession (); // Start a new session
}
}
同样,一切正常,一段时间,但身份验证到期。我理解it should,但我认为保存在AccountStore中的凭据应该仍然有效。
在Xamarin.Auth getting started docs中,它表示再次调用Save将覆盖凭据,并且“这对于使帐户对象中存储的凭据到期的服务很方便”。听起来很有希望......
所以我尝试了另一种方法:拥有一个始终覆盖getter中凭据的IsSignedIn属性......
public bool IsSignedIn {
get {
if (Authenticator == null) {
m_isSignedIn = false;
return m_isSignedIn;
}
if (Authenticator.Account != null) {
Store.Save (Authenticator.Account, "google"); // refresh the account store
Authenticator.Account = SavedAccount;
m_isSignedIn = StartService ();
} else {
m_isSignedIn = false;
}
return m_isSignedIn;
}
}
...然后在任何API调用(获取元数据,下载等)之前访问IsSignedIn。它不起作用:我上面仍然显示过期的凭据错误。
这是否需要refresh the token?我究竟做错了什么?
答案 0 :(得分:2)
访问令牌应该相对较快到期。这就是为什么在第一次授权之后你还会收到一个refresh_token,你可以用它来获取一个新的访问令牌,如果当前的一个到期。连续的auths不会给你一个刷新令牌,所以一定要保留你收到的那个!
访问令牌变为无效后,您只需使用refresh_token并将OAuthRequest发送到Google OAuth端点的token_url。
var postDictionary = new Dictionary<string, string>();
postDictionary.Add("refresh_token", googleAccount.Properties["refresh_token"]);
postDictionary.Add("client_id", "<<your_client_id>>");
postDictionary.Add("client_secret", "<<your_client_secret>>");
postDictionary.Add("grant_type", "refresh_token");
var refreshRequest = new OAuth2Request ("POST", new Uri (OAuthSettings.TokenURL), postDictionary, googleAccount);
refreshRequest.GetResponseAsync().ContinueWith (task => {
if (task.IsFaulted)
Console.WriteLine ("Error: " + task.Exception.InnerException.Message);
else {
string json = task.Result.GetResponseText();
Console.WriteLine (json);
try {
<<just deserialize the json response, eg. with Newtonsoft>>
}
catch (Exception exception) {
Console.WriteLine("!!!!!Exception: {0}", exception.ToString());
Logout();
}
}
});