將多個身份驗證提供者連結到 Apple 平台上的帳戶

您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,方法是將身份驗證提供程序憑據鏈接到現有用戶帳戶。用戶可以通過相同的 Firebase 用戶 ID 進行識別,而不管他們用於登錄的身份驗證提供程序如何。例如,使用密碼登錄的用戶可以關聯 Google 帳戶並在未來使用任一方法登錄。或者,匿名用戶可以鏈接 Facebook 帳戶,然後使用 Facebook 登錄以繼續使用您的應用程序。

在你開始之前

向您的應用程序添加對兩個或更多身份驗證提供程序(可能包括匿名身份驗證)的支持。

要將身份驗證提供者憑據鏈接到現有用戶帳戶:

  1. 使用任何身份驗證提供程序或方法登錄用戶。
  2. 完成新身份驗證提供程序的登錄流程,直到但不包括調用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

    谷歌登錄
    迅速
    guard
      let authentication = user?.authentication,
      let idToken = authentication.idToken
    else {
      return
    }
    
    let credential = GoogleAuthProvider.credential(withIDToken: idToken,
                                                   accessToken: authentication.accessToken)
    
    目標-C
    FIRAuthCredential *credential =
    [FIRGoogleAuthProvider credentialWithIDToken:result.user.idToken.tokenString
                                     accessToken:result.user.accessToken.tokenString];
    
    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. FIRAuthCredential對像傳遞給登錄用戶的linkWithCredential:completion:方法:

    迅速
        user.link(with: credential) { authResult, error in
      // ...
    }
    }
    
    目標-C
        [[FIRAuth auth].currentUser linkWithCredential:credential
        completion:^(FIRAuthDataResult *result, NSError *_Nullable error) {
      // ...
    }];
    

    如果憑據已鏈接到另一個用戶帳戶,則對linkWithCredential:completion:調用將失敗。在這種情況下,您必鬚根據您的應用程序處理合併帳戶和關聯數據:

    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,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。

您可以取消身份驗證提供程序與帳戶的鏈接,以便用戶無法再使用該提供程序登錄。

要取消身份驗證提供程序與用戶帳戶的鏈接,請將提供程序 ID 傳遞給unlink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) {
  // ...
}];