解析-PFTwitterUtils：获取用户的电子邮件地址

Question

I have an app where you can sign up using Facebook and Twitter via Parse SDK integration. This works just fine.

While signing up I need to retrieve the user's email address and save it. This works very easily with the Facebook login but I am unclear on how to do this when the user signs up via Twitter.

This is the code I am using:

[PFTwitterUtils logInWithBlock:^(PFUser *user, NSError *error) {

    if (!user)
    {
        ...
    }
    else
    {
        NSString * requestString = [NSString stringWithFormat:@"https://api.twitter.com/1.1/users/show.json?screen_name=%@", [PFTwitterUtils twitter].screenName];

        NSURL *verify = [NSURL URLWithString:requestString];
        NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:verify];

        [[PFTwitterUtils twitter] signRequest:request];

        NSError *dataError;
        NSURLResponse *response = nil;
        NSData *data = [NSURLConnection sendSynchronousRequest:request
                                             returningResponse:&response
                                                         error:&dataError];
        if (!dataError)
        {
            NSDictionary *result = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:&error];

            ...
        }
    }

}];

Unfortunately the result dictionary does not reveal any email address.

Any help will be much appreciated. Thanks in advance!

Answer 1

This is now possible by filling out a form to request elevated permissions:

Go to https://support.twitter.com/forms/platform Select "I need access to special permissions"

Enter Application Name and ID. These can be obtained via https://apps.twitter.com/ -- the application ID is the numeric part in the browser's address bar after you click your app.

Permissions Request: "Email address" Submit & wait for response

After your request is granted, an addition permission setting is added in your twitter app's "Permission" section. Go to "Additional Permissions" and just tick the checkbox for "Request email addresses from users".

Answer 2

Twitter is very sensitive when it comes to passing the email address further along to the developer. You basically need to show an extra screen asking the user's email address and its explicit consent.

Please note that your Twitter app needs to have access to getting the user's email address for this piece of code to actually return what you need. You need whitelist it and to submit for a review, similar to Facebook login permissions. (only apps created via apps.twitter.com and not the ones automatically generated via Fabric. I have a confirmation that the latter ones are not allowed to retrieve the user's email address)

This is a complete working example of a Twitter signup/login flow (what interests you is in the if ! block):

 - (IBAction)loginWithTwitter:(id)sender {
        [[Twitter sharedInstance] logInWithCompletion:^
         (TWTRSession *session, NSError *error) {
             if (error) {
                 // You can show an UI alert with the error.localizedDescription
             } else {
                 // you can show any progress hud here (to prevent UI changes)
                 [ConnectionManager loginWithSocialProvider:LoginMethodTypeTwitter token:session.authToken success:^(id responseObj) {
                     NSLog(@"response from twitter login : %@", responseObj);
                     // dismiss your progress hud here (unless you perform additional network calls)
                     BOOL userExists = ![[responseObj valueForKey:@"UserNotFound"] boolValue]; // this is a check in my custom API response - if the user exists
                     if (userExists) {
                         // perform a login here with the above credentials
                     } else {
                         TWTRShareEmailViewController* shareEmailViewController =
                         [[TWTRShareEmailViewController alloc]
                          initWithCompletion:^(NSString* email, NSError* error) {
                              NSLog(@"Email %@, Error: %@", email, error);
                              [self launchPostSignupWithName:nil email:email token:session.authToken username:session.userName provider:LoginMethodTypeTwitter];
                          }];
                         // The code is being called on the main thread already. this is fail proof
                         dispatch_async(dispatch_get_main_queue(), ^{
                             [self presentViewController:shareEmailViewController
                                                animated:YES
                                              completion:nil];
                         });                     
                     }
                 } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
                     // show an alert here and dismiss your progress hud as well, if any
                 }];
             }
         }];
    }

Answer 3

Swift version of Danut Pralea response

let twitterUserID = PFTwitterUtils.twitter()?.userId
let twitterScreenName = PFTwitterUtils.twitter()?.screenName

var twitterURL = "https://api.twitter.com/1.1/users/show.json?"
if let userID = twitterUserID{
    twitterURL = twitterURL + "user_id=" + userID
}else if let screenName = twitterScreenName{
    twitterURL = twitterURL + "screen_name=" + screenName
}else{
    print("Something's not right")
    return
}

let verify = NSURL(string: twitterURL)
let request = NSMutableURLRequest(URL: verify!)
PFTwitterUtils.twitter()?.signRequest(request)

NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue()) { (response: NSURLResponse?, data: NSData?, error: NSError?) -> Void in
    if error == nil{

        do {
            let JSON = try NSJSONSerialization.JSONObjectWithData(data!, options:NSJSONReadingOptions(rawValue: 0))
            guard let JSONDictionary :NSDictionary = JSON as? NSDictionary else {
                print("Not a Dictionary")
                // put in function
                return
            }
            print("JSONDictionary! \(JSONDictionary)")

            let user = PFUser.currentUser()

            let profileImage = JSONDictionary["profile_image_url_https"] as! String
            if !profileImage.isEmpty{
                user!["profileImageAvatar"] = profileImage
            }

            let screenName = JSONDictionary["screen_name"] as! String
            if !screenName.isEmpty{
                user!["screen_name"] = screenName
            }

            let userName = JSONDictionary["name"] as! String
            if !userName.isEmpty{
                user!["username"] = userName
            }else if !screenName.isEmpty{
                user!["username"] = screenName
            }

            user?.saveInBackgroundWithBlock({ (status, error) -> Void in
                if error == nil{
                    print("twitter data saved")
                }else{
                    print("error saving twitter data")
                    print(error)
                }
            })
        }
        catch let JSONError as NSError {
            print("\(JSONError)")
        }


    }
}