本頁面由 Cloud Translation API 翻譯而成。
Switch to English

將多個身份驗證提供程序鏈接到iOS上的帳戶

通過將身份驗證提供程序憑據鏈接到現有用戶帳戶,可以允許用戶使用多個身份驗證提供程序登錄您的應用程序。無論使用哪種身份驗證提供程序登錄,都可以使用相同的Firebase用戶ID來識別用戶。例如,使用密碼登錄的用戶將來可以鏈接Google帳戶並使用這兩種方法登錄。或者,匿名用戶可以鏈接一個Facebook帳戶,然後再登錄Facebook以繼續使用您的應用程序。

在你開始之前

向您的應用添加對兩個或多個身份驗證提供程序的支持(可能包括匿名身份驗證)。

要將身份驗證提供程序憑據鏈接到現有用戶帳戶,請執行以下操作:

  1. 使用任何身份驗證提供程序或方法登錄用戶。
  2. 完成新的身份驗證提供程序的登錄流程,但不包括調用FIRAuth.signInWith方法之一。例如,獲取用戶的Google ID令牌,Facebook訪問令牌或電子郵件和密碼。
  3. 獲取新身份驗證提供程序的FIRAuthCredential

    Google登錄
    迅速
    guard let authentication = user.authentication else { return }
    let credential = GoogleAuthProvider.credential(withIDToken: authentication.idToken,
                                                      accessToken: authentication.accessToken)
    
    目標C
    GIDAuthentication *authentication = user.authentication;
    FIRAuthCredential *credential =
    [FIRGoogleAuthProvider credentialWithIDToken:authentication.idToken
                                     accessToken:authentication.accessToken];
    
    Facebook登入
    迅速
    let credential = FacebookAuthProvider.credential(withAccessToken: AccessToken.current!.tokenString)
    
    目標C
    FIRAuthCredential *credential = [FIRFacebookAuthProvider
        credentialWithAccessToken:[FBSDKAccessToken currentAccessToken].tokenString];
    
    電子郵件密碼登錄
    迅速
    let credential = EmailAuthProvider.credential(withEmail: email, password: password)
    
    目標C
    FIRAuthCredential *credential =
        [FIREmailAuthProvider credentialWithEmail:email
                                                 password:password];
    
  4. FIRAuthCredentialFIRAuthCredential傳遞給登錄用戶的linkWithCredential:completion:方法:

    迅速
        user.link(with: credential) { (authResult, error) in
      // ...
    }
    }
    
    目標C
    076

    如果憑據已鏈接到另一個用戶帳戶,則對linkWithCredential:completion:的調用將失敗。在這種情況下,您必鬚根據自己的應用程序合併帳戶和相關數據:

    迅速

    let prevUser = Auth.auth().currentUser
    Auth.auth().signIn(with: credential) { (authResult, error) in
      if let error = error {
        let authError = error as NSError
        if (isMFAEnabled && authError.code == AuthErrorCode.secondFactorRequired.rawValue) {
          // The user is a multi-factor user. Second factor challenge is required.
          let resolver = authError.userInfo[AuthErrorUserInfoMultiFactorResolverKey] as! MultiFactorResolver
          var displayNameString = ""
          for tmpFactorInfo in (resolver.hints) {
            displayNameString += tmpFactorInfo.displayName ?? ""
            displayNameString += " "
          }
          self.showTextInputPrompt(withMessage: "Select factor to sign in\n\(displayNameString)", completionBlock: { userPressedOK, displayName in
            var selectedHint: PhoneMultiFactorInfo?
            for tmpFactorInfo in resolver.hints {
              if (displayName == tmpFactorInfo.displayName) {
                selectedHint = tmpFactorInfo as? PhoneMultiFactorInfo
              }
            }
            PhoneAuthProvider.provider().verifyPhoneNumber(with: selectedHint!, uiDelegate: nil, multiFactorSession: resolver.session) { verificationID, error in
              if error != nil {
                print("Multi factor start sign in failed. Error: \(error.debugDescription)")
              } else {
                self.showTextInputPrompt(withMessage: "Verification code for \(selectedHint?.displayName ?? "")", completionBlock: { userPressedOK, verificationCode in
                  let credential: PhoneAuthCredential? = PhoneAuthProvider.provider().credential(withVerificationID: verificationID!, verificationCode: verificationCode!)
                  let assertion: MultiFactorAssertion? = PhoneMultiFactorGenerator.assertion(with: credential!)
                  resolver.resolveSignIn(with: assertion!) { authResult, error in
                    if error != nil {
                      print("Multi factor finanlize sign in failed. Error: \(error.debugDescription)")
                    } else {
                      self.navigationController?.popViewController(animated: true)
                    }
                  }
                })
              }
            }
          })
        } else {
          self.showMessagePrompt(error.localizedDescription)
          return
        }
        // ...
        return
      }
      // User is signed in
      // ...
    }
                // Merge prevUser and currentUser accounts and data
                // ...
            }
    

    目標C

    FIRUser *prevUser = [FIRAuth auth].currentUser;
    [[FIRAuth auth] signInWithCredential:credential
                              completion:^(FIRAuthDataResult * _Nullable authResult,
                                           NSError * _Nullable error) {
        if (isMFAEnabled && error && error.code == FIRAuthErrorCodeSecondFactorRequired) {
          FIRMultiFactorResolver *resolver = error.userInfo[FIRAuthErrorUserInfoMultiFactorResolverKey];
          NSMutableString *displayNameString = [NSMutableString string];
          for (FIRMultiFactorInfo *tmpFactorInfo in resolver.hints) {
            [displayNameString appendString:tmpFactorInfo.displayName];
            [displayNameString appendString:@" "];
          }
          [self showTextInputPromptWithMessage:[NSString stringWithFormat:@"Select factor to sign in\n%@", displayNameString]
                               completionBlock:^(BOOL userPressedOK, NSString *_Nullable displayName) {
           FIRPhoneMultiFactorInfo* selectedHint;
           for (FIRMultiFactorInfo *tmpFactorInfo in resolver.hints) {
             if ([displayName isEqualToString:tmpFactorInfo.displayName]) {
               selectedHint = (FIRPhoneMultiFactorInfo *)tmpFactorInfo;
             }
           }
           [FIRPhoneAuthProvider.provider
            verifyPhoneNumberWithMultiFactorInfo:selectedHint
            UIDelegate:nil
            multiFactorSession:resolver.session
            completion:^(NSString * _Nullable verificationID, NSError * _Nullable error) {
              if (error) {
                [self showMessagePrompt:error.localizedDescription];
              } else {
                [self showTextInputPromptWithMessage:[NSString stringWithFormat:@"Verification code for %@", selectedHint.displayName]
                                     completionBlock:^(BOOL userPressedOK, NSString *_Nullable verificationCode) {
                 FIRPhoneAuthCredential *credential =
                     [[FIRPhoneAuthProvider provider] credentialWithVerificationID:verificationID
                                                                  verificationCode:verificationCode];
                 FIRMultiFactorAssertion *assertion = [FIRPhoneMultiFactorGenerator assertionWithCredential:credential];
                 [resolver resolveSignInWithAssertion:assertion completion:^(FIRAuthDataResult * _Nullable authResult, NSError * _Nullable error) {
                   if (error) {
                     [self showMessagePrompt:error.localizedDescription];
                   } else {
                     NSLog(@"Multi factor finanlize sign in succeeded.");
                   }
                 }];
               }];
              }
            }];
         }];
        }
      else if (error) {
        // ...
        return;
      }
      // User successfully signed in. Get user data from the FIRUser object
      if (authResult == nil) { return; }
      FIRUser *user = authResult.user;
      // ...
    }];
                                        // Merge prevUser and currentUser accounts and data
                                        // ...
                                    }];
    

如果對linkWithCredential:completion:的調用成功,則用戶現在可以使用任何鏈接的身份驗證提供程序登錄並訪問相同的Firebase數據。

您可以取消與帳戶的身份驗證提供程序的鏈接,以便用戶無法再使用該提供程序登錄。

要將身份驗證提供程序與用戶帳戶斷開鏈接,請將提供程序ID傳遞給unlinkFromProvider:completion:方法。您可以從providerData屬性獲取鏈接到用戶的身份驗證提供程序的提供程序ID。

迅速

Auth.auth().currentUser?.unlink(fromProvider: providerID!) { (user, error) in
  // ...
}

目標C

[[FIRAuth auth].currentUser unlinkFromProvider:providerID
                                    completion:^(FIRUser *_Nullable user, NSError *_Nullable error) {
  // ...
}];