目标c clear NSURLCredential - NSURLCredentialPersistenceForSession

Question

我在这个方法中使用NSURLCredentials：

-(void)UserLogin:(NSString *)user andPassWordExists:(NSString *)password completionHandler:(void (^)(NSArray *resultsObject, NSError *error))completionHandler
{


   NSURL *url = [NSURL URLWithString:kIP];
   NSURLRequest *request = [NSURLRequest requestWithURL:url];

    AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc]
                                         initWithRequest:request];


    NSURLCredential *credential = [NSURLCredential
                                   credentialWithUser:user
                                   password:password
                                   persistence:NSURLCredentialPersistenceForSession];

    [operation setCredential:credential];

    [[NSOperationQueue mainQueue] addOperation:operation];

    [operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {

        if (completionHandler) {
            completionHandler(responseObject, nil);
        }

    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {

        if (completionHandler) {
            completionHandler(nil, error);
        }

    }];

    [operation start];
}

现在，我希望在这样的注销方法中清除NSURLCredentials：

-(void)logout
{
   //Clear NSURLCredentialPersistenceForSession
}

我该怎么做呢？我是要重置NSURLCredentials，还是要清除它们？

更新

我找到了这个解决方案：

NSURLCredentialStorage *credentialStorage = [NSURLCredentialStorage sharedCredentialStorage];
    NSDictionary *credentialsDicationary = [credentialStorage allCredentials];


    for (NSURLProtectionSpace *space in [credentialsDicationary allKeys]) {

        NSDictionary *spaceDictionary = [credentialsDicationary objectForKey:space];

        for (id userName in [spaceDictionary allKeys]) {

            NSURLCredential *credential = [spaceDictionary objectForKey:userName];

            [credentialStorage removeCredential:credential forProtectionSpace:space];

        }

    }

出发地：Using NSURLCredentialPersistenceForSession while request and then clearing the credentials on logout still persist the cerdentials

这是最好的方法吗？我只存了一张证件。另外，这段代码在这一行上给了我一个警告：

NSURLCredential *credential = [spaceDictionary objectForKey:userName];

这是warning...how，我要删除这个警告吗？

/Users/jsuske/Documents/SSiPad(Device Only)ios7/SchedulingiPadApplication/ViewControllers/LHLoginController.m:496:73: Local declaration of 'userName' hides instance variable

更新

好的，我有三个方法:UserLogin，Login和LogoutButtonPressed

UserLogin:我使用AFNetworking连接到一个使用NSURLCredential进行身份验证的NSURLCredential，如下所示：

-(void)UserLogin:(NSString *)user andPassWordExists:(NSString *)password completionHandler:(void (^)(NSArray *resultsObject, NSError *error))completionHandler
{

   NSURL *url = [NSURL URLWithString:kIP];
   NSURLRequest *request = [NSURLRequest requestWithURL:url];

    AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc]
                                         initWithRequest:request];

    NSURLCredential *credential = [NSURLCredential
                                   credentialWithUser:user
                                   password:password
                                   persistence:NSURLCredentialPersistenceForSession];

    [operation setCredential:credential];


    [[NSOperationQueue mainQueue] addOperation:operation];

    [operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {

        if (completionHandler) {
            completionHandler(responseObject, nil);
        }

    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {

        if (completionHandler) {
            completionHandler(nil, error);
        }

    }];

    [operation start];

}

Login方法正在调用此方法：

- (void)Login
{
    NSString *rawString = [self.idTextField text];
    NSCharacterSet *whitespace = [NSCharacterSet whitespaceAndNewlineCharacterSet];
    [self.idTextField setText:[rawString stringByTrimmingCharactersInSet:whitespace]];


    [userName UserLogin:self.idTextField.text andPassWordExists:self.passwordTextField.text completionHandler:^(id responseObject, NSError *error) {
        if (responseObject) {

                [self.idTextField removeFromSuperview];
                [self.passwordTextField removeFromSuperview];
                [self.loginButton removeFromSuperview];
                self.idTextField = nil;
                self.passwordTextField = nil;
                //self.loginButton = nil;


                [self CreateMenu];



                [indicatorView stopAnimating];
                [indicatorView removeFromSuperview];
                indicatorView = nil;
                [loadingView removeFromSuperview];
                loadingView = nil;
        }else{


            [self CustomAlert:@"Sorry Login Failed, User and/or Passsword Incorrect"];

            [indicatorView stopAnimating];
            [indicatorView removeFromSuperview];
            indicatorView = nil;
            [loadingView removeFromSuperview];
            loadingView = nil;

        }
    }];

}

我正试着用LogoutButtonPressed来结束我的会议：

- (void)LogoutButtonPressed
{

    //@TODO: Fix Logout

    NSDictionary *credentialsDict = [[NSURLCredentialStorage sharedCredentialStorage] allCredentials];

    if ([credentialsDict count] > 0) {
        NSEnumerator *protectionSpaceEnumerator = [credentialsDict keyEnumerator];
        id urlProtectionSpace;

        while (urlProtectionSpace = [protectionSpaceEnumerator nextObject]) {
            NSEnumerator *userNameEnumerator = [[credentialsDict objectForKey:urlProtectionSpace] keyEnumerator];
            id userNameCred;

            while (userNameCred = [userNameEnumerator nextObject]) {
                NSURLCredential *cred = [[credentialsDict objectForKey:urlProtectionSpace] objectForKey:userNameCred];
                NSLog(@"cred to be removed: %@", cred);
                [[NSURLCredentialStorage sharedCredentialStorage] removeCredential:cred forProtectionSpace:urlProtectionSpace];
            }
        }
    }
}

我从这个例子中获得了以下代码：http://www.springenwerk.com/2008/11/i-am-currently-building-iphone.html

现在我遇到的问题是，当我触发注销按钮，然后触发没有凭据的登录方法时，我仍然可以登录，如果我注销，那么等待2-3分钟，然后在没有凭据的情况下登录，我无法登录。为什么它的行为是这样的，它几乎就像信用仍然被拯救。请帮帮忙。

更新

我试图清除LogoutButtonPressed中的缓存、cookie和tried：

NSURLCache *sharedCache = [NSURLCache sharedURLCache];
[sharedCache removeAllCachedResponses];

NSHTTPCookieStorage *cookieStorage = [NSHTTPCookieStorage sharedHTTPCookieStorage];
NSArray *cookies = [cookieStorage cookies];
id cookie;
for (cookie in cookies) {
    [cookieStorage deleteCookie:cookie];
}

NSDictionary *credentialsDict = [[NSURLCredentialStorage sharedCredentialStorage] allCredentials];
if ([credentialsDict count] > 0) {
    NSEnumerator *protectionSpaceEnumerator = [credentialsDict keyEnumerator];
    id urlProtectionSpace;
    while (urlProtectionSpace = [protectionSpaceEnumerator nextObject]) {
        NSEnumerator *userNameEnumerator = [[credentialsDict objectForKey:urlProtectionSpace] keyEnumerator];
        id userNameCreds;
        while (userNameCreds = [userNameEnumerator nextObject]) {
            NSURLCredential *cred = [[credentialsDict objectForKey:urlProtectionSpace] objectForKey:userNameCreds];
            [[NSURLCredentialStorage sharedCredentialStorage] removeCredential:cred forProtectionSpace:urlProtectionSpace];
        }
    }
}

但还是没起作用。

Answer 1

通过在URL末尾添加一个随机数，可以很容易地解决此问题：

-(void)UserLogin:(NSString *)user andPassWordExists:(NSString *)password completionHandler:(void (^)(NSArray *resultsObject, NSError *error))completionHandler
{
   NSInteger randomNumber = arc4random() % 999;

   NSString *requestURL = [NSString stringWithFormat:@"%@?cache=%ld",kIP,(long)randomNumber];

   NSURL *url = [NSURL URLWithString:requestURL];

   NSURLRequest *request = [NSURLRequest requestWithURL:url];
     AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc]
                                         initWithRequest:request];

   NSURLCredential *credential = [NSURLCredential
                                   credentialWithUser:user
                                   password:password
                                   persistence:NSURLCredentialPersistenceForSession];


    [operation setCredential:credential];
    operation.responseSerializer = [AFJSONResponseSerializer serializer];
    [[NSOperationQueue mainQueue] addOperation:operation];


    [operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {

        if (completionHandler) {
            completionHandler(responseObject, nil);
        }

    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {

        if (completionHandler) {
            completionHandler(nil, error);
        }

    }];

    [operation start];

}

并确保在您调用的所有URL的末尾都有一个随机数。

Answer 2

LogoutButtonPressed正在从NSURLCredentialStorage中删除凭据，同时迭代相同的凭据-- NSEnumerator不支持这一点。您是否在日志中看到“将被移除的”消息？

您可以尝试使用来自_resetCredentials的m.html方法。

不管这是否有区别，检查resetCredentials调用之前和之后的_dumpCredentials输出都会很有趣，或者最好还是在登录方法中进行转储，并查看在重置之后以及2-3分钟后是否有更改。

self.passwordTextField.text被清除了吗？在它登录的无凭据情况下，NSURLCredential credentialWithUser:是否给出了零？