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使用SwiftUI、Combine和Firebase,在将用户的帐户链接到电子邮件/密码之前,我如何验证用户是否匿名登录?

swiftui firebase-authentication firebase swift

Zach Marion · 技术社区 · 4 年前

我有一个具有以下功能的AuthService:

func signInAnon() -> AnyPublisher<User, AuthError> {
    return Future<User, AuthError> { promise in
        Auth.auth().signInAnonymously { result, error in
            if let error = error {
                return promise(.failure(.signInAnon(description: error.localizedDescription)))
            } else if let user = result?.user {
                return promise(.success(user))
            }
        }
    }.eraseToAnyPublisher()
}

func linkAccount(email: String, password: String) -> AnyPublisher<User, AuthError> {
    
    let emailCredential = EmailAuthProvider.credential(withEmail: email, password: password)
    
    return Future<User, AuthError> { promise in
        Auth.auth().currentUser?.link(with: emailCredential) { result, error in
            if let error = error {
                return promise(.failure(.linkAccount(description: error.localizedDescription)))
            } else if let user = result?.user {
                Auth.auth().updateCurrentUser(user) { error in
                    if let error = error {
                        return promise(.failure(.updateCurrentUser(description: error.localizedDescription)))
                    } else {
                        return promise(.success((user)))
                    }
                }
            }
        }
    } .eraseToAnyPublisher()
}

在ViewModel中,我想将用户的匿名帐户与电子邮件/密码凭据链接起来。然而,在登录时,匿名登录尚未发生。

以下是我ViewModel中的代码:

case .signUp:

isLoading = true

authService.signInAnon()
    .timeout(.seconds(5), scheduler: DispatchQueue.main, options: nil, customError: { () -> AuthError in
        return .signInAnon(description: self.error?.localizedDescription)})
    .sink { completion in
        switch completion {
        case let .failure(error):
            self.error = error
        case .finished:
            print("User signed in anonymously")
            self.error = nil
            }
    } receiveValue: { user in
        self.user = user
    }
    .store(in: &cancellables)

authService.linkAccount(email: email, password: password)
    .timeout(.seconds(5), scheduler: DispatchQueue.main, options: nil, customError: { () -> AuthError in
        return .linkAccount(description: self.error?.localizedDescription)})
    .sink { completion in
    self.isLoading = false
    switch completion {
    case let .failure(error):
        self.error = error
        self.alertIsPresented = true
        print(error.localizedDescription)
    case .finished:
        print("Sign up successful")
    }
} receiveValue: { user in
    self.user = user
}
.store(in: &cancellables)

我遇到了问题,因为有时链接帐户的函数会在匿名登录函数之前完成,从而出现错误。

我如何有条件地写这个,以便检查用户是否匿名登录?如果是,请链接他们的帐户。如果他们没有,请匿名登录,然后链接他们的帐户。

0 回复 | 直到 4 年前

Peter Friese 4 年前

以下是我对如何使用Firebase匿名身份验证的建议:

一旦你的应用程序启动,初始化Firebase并检查一用户已登录。如果用户之前已登录,Firebase Auth将在您调用此方法之前及时获取该用户。
如果没有用户,请匿名登录。
然后,您可以开始使用受益于登录用户的所有Firebase服务(如Firestore)
一旦用户决定实际登录,使用任何Firebase身份验证提供程序获取令牌,并将其链接到现有的匿名用户。顺便说一句,我建议使用比电子邮件/密码更安全的东西。

在应用程序启动时执行匿名登录的示例代码(取自 this sample app ):

func signIn() {
  if Auth.auth().currentUser == nil {
    Auth.auth().signInAnonymously()
  }
}

升级到Apple帐户登录的示例代码(取自 the same sample app ):

      case .link:
        if let currentUser = Auth.auth().currentUser {
          currentUser.link(with: credential) { (result, error) in
            if let error = error, (error as NSError).code == AuthErrorCode.credentialAlreadyInUse.rawValue {
              print("The user you're signing in with has already been linked, signing in to the new user and migrating the anonymous users [\(currentUser.uid)] tasks.")
              
              if let updatedCredential = (error as NSError).userInfo[AuthErrorUserInfoUpdatedCredentialKey] as? OAuthCredential {
                print("Signing in using the updated credentials")
                Auth.auth().signIn(with: updatedCredential) { (result, error) in
                  if let user = result?.user {
                    currentUser.getIDToken { (token, error) in
                      if let idToken = token {
                        (self.taskRepository as? FirestoreTaskRepository)?.migrateTasks(from: idToken)
                        self.doSignIn(appleIDCredential: appleIDCredential, user: user)
                      }
                    }
                  }
                }
              }
            }
            else if let error = error {
              print("Error trying to link user: \(error.localizedDescription)")
            }
            else {
              if let user = result?.user {
                self.doSignIn(appleIDCredential: appleIDCredential, user: user)
              }
            }
          }
        }

如果您对Combine的情况感兴趣,我们已经开始为Firebase实现Combine支持-查看我们的 project tracker