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在 Apple 平台上使用 Facebook 登錄進行身份驗證

您可以通過將 Facebook 登錄或 Facebook 有限登錄集成到您的應用中,讓您的用戶使用他們的 Facebook 帳戶通過 Firebase 進行身份驗證。

在你開始之前

使用 Swift Package Manager 安裝和管理 Firebase 依賴項。

  1. 在Xcode中,您的應用項目打開,導航到File>斯威夫特包>添加包的依賴
  2. 出現提示時,添加 Firebase Apple 平台 SDK 存儲庫:
  3.   https://github.com/firebase/firebase-ios-sdk
      
  4. 選擇 Firebase 身份驗證庫。
  5. 完成後,Xcode 將在後台自動開始解析和下載您的依賴項。

接下來,執行一些配置步驟:

  1. Facebook上的開發者網站,獲取應用程序ID應用程式密鑰為您的應用程序。
  2. 啟用 Facebook 登錄:
    1. 火力地堡控制台,打開驗證部分。
    2. 登錄方法選項卡,使Facebook的登錄方法,並指定應用程序IDApp秘密你從Facebook獲得。
    3. 然後,請確保您的OAuth重定向URI(my-app-12345.firebaseapp.com/__/auth/handler )被列為上的Facebook應用程序的設置頁面您的OAuth重定向URI之一的Facebook面向開發人員產品網站設置> Facebook的登錄配置。

實施 Facebook 登錄

要使用“經典”Facebook 登錄,請完成以下步驟。或者,您可以使用 Facebook 限制登錄,如下一節所示。

  1. 整合Facebook登錄到您的應用程序通過以下的開發者文檔。當初始化FBSDKLoginButton對象,設置一個委託接收登錄和註銷事件。例如:

    迅速

    let loginButton = FBSDKLoginButton()
    loginButton.delegate = self
    

    目標-C

    FBSDKLoginButton *loginButton = [[FBSDKLoginButton alloc] init];
    loginButton.delegate = self;
    
    在您的委託,實施didCompleteWithResult:error:

    迅速

    func loginButton(_ loginButton: FBSDKLoginButton!, didCompleteWith result: FBSDKLoginManagerLoginResult!, error: Error!) {
      if let error = error {
        print(error.localizedDescription)
        return
      }
      // ...
    }
    

    目標-C

    - (void)loginButton:(FBSDKLoginButton *)loginButton
        didCompleteWithResult:(FBSDKLoginManagerLoginResult *)result
                        error:(NSError *)error {
      if (error == nil) {
        // ...
      } else {
        NSLog(error.localizedDescription);
      }
    }
    
  2. 導入火力地堡模塊在UIApplicationDelegate

    迅速

    import Firebase

    目標-C

    @import Firebase;
  3. 配置一個FirebaseApp共享實例,通常在你的應用程序的application:didFinishLaunchingWithOptions:方法:

    迅速

    // Use Firebase library to configure APIs
    FirebaseApp.configure()

    目標-C

    // Use Firebase library to configure APIs
    [FIRApp configure];
  4. 當用戶在成功的跡象,在你執行didCompleteWithResult:error: ,得到令牌換成訪問的登錄用戶並換取一個火力地堡憑證:

    迅速

    let credential = FacebookAuthProvider
      .credential(withAccessToken: AccessToken.current!.tokenString)
    

    目標-C

    FIRAuthCredential *credential = [FIRFacebookAuthProvider
        credentialWithAccessToken:[FBSDKAccessToken currentAccessToken].tokenString];
    

實施 Facebook 限制登錄

要使用 Facebook 限制登錄而不是“經典”Facebook 登錄,請完成以下步驟。

  1. 整合Facebook有限公司登錄到您的應用程序通過以下的開發者文檔
  2. 對於每個登錄請求,生成一個唯一的隨機字符串 - “nonce” - 您將使用它來確保您獲得的 ID 令牌是專門為響應您的應用程序的身份驗證請求而授予的。這一步對於防止重放攻擊很重要。您可以生成一個加密的安全隨機數SecRandomCopyBytes(_:_:_)如下面的例子:

    迅速

    // Adapted from https://auth0.com/docs/api-auth/tutorials/nonce#generate-a-cryptographically-random-nonce
    private func randomNonceString(length: Int = 32) -> String {
      precondition(length > 0)
      let charset: [Character] =
        Array("0123456789ABCDEFGHIJKLMNOPQRSTUVXYZabcdefghijklmnopqrstuvwxyz-._")
      var result = ""
      var remainingLength = length
    
      while remainingLength > 0 {
        let randoms: [UInt8] = (0 ..< 16).map { _ in
          var random: UInt8 = 0
          let errorCode = SecRandomCopyBytes(kSecRandomDefault, 1, &random)
          if errorCode != errSecSuccess {
            fatalError(
              "Unable to generate nonce. SecRandomCopyBytes failed with OSStatus \(errorCode)"
            )
          }
          return random
        }
    
        randoms.forEach { random in
          if remainingLength == 0 {
            return
          }
    
          if random < charset.count {
            result.append(charset[Int(random)])
            remainingLength -= 1
          }
        }
      }
    
      return result
    }
    
            

    目標-C

    // Adapted from https://auth0.com/docs/api-auth/tutorials/nonce#generate-a-cryptographically-random-nonce
    - (NSString *)randomNonce:(NSInteger)length {
      NSAssert(length > 0, @"Expected nonce to have positive length");
      NSString *characterSet = @"0123456789ABCDEFGHIJKLMNOPQRSTUVXYZabcdefghijklmnopqrstuvwxyz-._";
      NSMutableString *result = [NSMutableString string];
      NSInteger remainingLength = length;
    
      while (remainingLength > 0) {
        NSMutableArray *randoms = [NSMutableArray arrayWithCapacity:16];
        for (NSInteger i = 0; i < 16; i++) {
          uint8_t random = 0;
          int errorCode = SecRandomCopyBytes(kSecRandomDefault, 1, &random);
          NSAssert(errorCode == errSecSuccess, @"Unable to generate nonce: OSStatus %i", errorCode);
    
          [randoms addObject:@(random)];
        }
    
        for (NSNumber *random in randoms) {
          if (remainingLength == 0) {
            break;
          }
    
          if (random.unsignedIntValue < characterSet.length) {
            unichar character = [characterSet characterAtIndex:random.unsignedIntValue];
            [result appendFormat:@"%C", character];
            remainingLength--;
          }
        }
      }
    
      return [result copy];
    }
            
    您將隨登錄請求發送隨機數的 SHA-256 哈希值,Facebook 將在響應中原封不動地傳遞該哈希值。 Firebase 通過散列原始隨機數並將其與 Facebook 傳遞的值進行比較來驗證響應。

    迅速

    @available(iOS 13, *)
    private func sha256(_ input: String) -> String {
      let inputData = Data(input.utf8)
      let hashedData = SHA256.hash(data: inputData)
      let hashString = hashedData.compactMap {
        String(format: "%02x", $0)
      }.joined()
    
      return hashString
    }
    
            

    目標-C

    - (NSString *)stringBySha256HashingString:(NSString *)input {
      const char *string = [input UTF8String];
      unsigned char result[CC_SHA256_DIGEST_LENGTH];
      CC_SHA256(string, (CC_LONG)strlen(string), result);
    
      NSMutableString *hashed = [NSMutableString stringWithCapacity:CC_SHA256_DIGEST_LENGTH * 2];
      for (NSInteger i = 0; i < CC_SHA256_DIGEST_LENGTH; i++) {
        [hashed appendFormat:@"%02x", result[i]];
      }
      return hashed;
    }
            
  3. 當您設置FBSDKLoginButton ,設置一個委託接收登錄和註銷事件,設置跟踪模式FBSDKLoginTrackingLimited ,並附加一個隨機數。例如:

    迅速

    func setupLoginButton() {
        let nonce = randomNonceString()
        currentNonce = nonce
        loginButton.delegate = self
        loginButton.loginTracking = .limited
        loginButton.nonce = sha256(nonce)
    }
            

    目標-C

    - (void)setupLoginButton {
      NSString *nonce = [self randomNonce:32];
      self.currentNonce = nonce;
      self.loginButton.delegate = self;
      self.loginButton.loginTracking = FBSDKLoginTrackingLimited
      self.loginButton.nonce = [self stringBySha256HashingString:nonce];
    }
            
    在您的委託,實施didCompleteWithResult:error:

    迅速

    func loginButton(_ loginButton: FBSDKLoginButton!, didCompleteWith result: FBSDKLoginManagerLoginResult!, error: Error!) {
      if let error = error {
        print(error.localizedDescription)
        return
      }
      // ...
    }
            

    目標-C

    - (void)loginButton:(FBSDKLoginButton *)loginButton
        didCompleteWithResult:(FBSDKLoginManagerLoginResult *)result
                        error:(NSError *)error {
      if (error == nil) {
        // ...
      } else {
        NSLog(error.localizedDescription);
      }
    }
            
  4. 導入火力地堡模塊在UIApplicationDelegate

    迅速

    import Firebase

    目標-C

    @import Firebase;
  5. 配置一個FirebaseApp共享實例,通常在你的應用程序的application:didFinishLaunchingWithOptions:方法:

    迅速

    // Use Firebase library to configure APIs
    FirebaseApp.configure()

    目標-C

    // Use Firebase library to configure APIs
    [FIRApp configure];
  6. 當用戶在成功的跡象,在你執行didCompleteWithResult:error:使用來自Facebook的與非散列隨機數響應令牌的ID來獲得一個火力地堡憑證:

    迅速

    // Initialize a Firebase credential.
    let idTokenString = AuthenticationToken.current?.tokenString
    let nonce = currentNonce
    let credential = OAuthProvider.credential(withProviderID: "facebook.com",
                                              idToken: idTokenString!,
                                              rawNonce: nonce)
            

    目標-C

    // Initialize a Firebase credential.
    NSString *idTokenString = FBSDKAuthenticationToken.currentAuthenticationToken.tokenString;
    NSString *rawNonce = self.currentNonce;
    FIROAuthCredential *credential = [FIROAuthProvider credentialWithProviderID:@"facebook.com"
                                                                        IDToken:idTokenString
                                                                       rawNonce:rawNonce];
            

使用 Firebase 進行身份驗證

最後,使用 Firebase 憑據對 Firebase 進行身份驗證:

迅速

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
    // ...
}
    

目標-C

[[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;
  // ...
}];
    

下一步

用戶首次登錄後,將創建一個新用戶帳戶並將其鏈接到用戶登錄時使用的憑據(即用戶名和密碼、電話號碼或身份驗證提供商信息)。這個新帳戶作為 Firebase 項目的一部分存儲,可用於識別項目中每個應用中的用戶,無論用戶如何登錄。

  • 在您的應用程序,你可以從用戶的基本資料信息FIRUser對象。請參閱管理用戶

  • 在你的火力地堡實時數據庫和雲存儲安全規則,你可以得到簽署的,從用戶的唯一的用戶ID auth的變量,並用它來控制哪些數據的用戶可以訪問。

您可以允許用戶通過使用多個身份驗證提供登錄到您的應用程序連接身份驗證提供憑據到現有的用戶帳戶。

要註銷用戶,請撥打signOut:

迅速

    let firebaseAuth = Auth.auth()
do {
  try firebaseAuth.signOut()
} catch let signOutError as NSError {
  print("Error signing out: %@", signOutError)
}
  

目標-C

    NSError *signOutError;
BOOL status = [[FIRAuth auth] signOut:&signOutError];
if (!status) {
  NSLog(@"Error signing out: %@", signOutError);
  return;
}

您可能還想為所有身份驗證錯誤添加錯誤處理代碼。請參見處理錯誤