如何在RxSwift中实现firebase身份验证

import Firebase
import RxSwift

let auth = Auth.auth()

let authResultSubject = PublishSubject<AuthDataResult>()

let authStateObserver = auth.rx.authState
    .subscribe(onNext: { authDataResult in
        authResultSubject.onNext(authDataResult)
    }, onError: { error in
        authResultSubject.onError(error)
    })

func signIn(email: String, password: String) -> Observable<AuthDataResult> {
    return Observable.create { observer in
        auth.signIn(withEmail: email, password: password) { authDataResult, error in
            if let error = error {
                observer.onError(error)
            } else if let authDataResult = authDataResult {
                observer.onNext(authDataResult)
                observer.onCompleted()
            }
        }
        return Disposables.create()
    }
}

signIn(email: "example@example.com", password: "password")
    .subscribe(onNext: { authDataResult in
        // 身份验证成功
    }, onError: { error in
        // 身份验证失败
    })
    .disposed(by: disposeBag)