ログイン画面をMVVMへリファクタリング

hack_iOS/Sources/View/LoginViewController.swift

@@ -28,24 +28,25 @@ final class LoginViewController: UIViewController, UITextFieldDelegate {
     @IBOutlet private weak var loginButton: UIButton! {
         didSet {
             loginButton.setTitle("Login", for: .normal)
-            loginButton.addTarget(self, action: #selector(tapLoginButton), for: .touchUpInside)
         }
     }
 
     @IBOutlet private weak var moveToSignUpViewButton: UIButton! {
         didSet {
             moveToSignUpViewButton.setTitle("SignupView", for: .normal)
-            moveToSignUpViewButton.addTarget(self, action: #selector(tapMoveToSignUpViewButton), for: .touchUpInside)
         }
     }
 
-    private let authRepository: AuthRepository
-    private let keychainAccessRepository: KeychainAccessRepository
     private let disposeBag = DisposeBag()
+    private let viewModel: LoginViewModelType
 
-    init(authRepository: AuthRepository = .init(), keychainAccessRepository: KeychainAccessRepository = .init()) {
-        self.authRepository = authRepository
-        self.keychainAccessRepository = keychainAccessRepository
+    init(
+        authRepository: AuthRepository = .init(),
+        keychainAccessRepository: KeychainAccessRepository = .init()
+    ){
+        self.viewModel = LoginViewModel(
+            dependency: .init(authrepository: authRepository, keychainAccessRepository: keychainAccessRepository)
+        )
         super.init(nibName: nil, bundle: nil)
     }
 
@@ -56,61 +57,53 @@ final class LoginViewController: UIViewController, UITextFieldDelegate {
 
     override func viewDidLoad() {
         super.viewDidLoad()
+        bindViewModel()
     }
 
-    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
-        self.view.endEditing(true)
-    }
-
-    @objc private func tapLoginButton() {
-        login()
-    }
-
-    @objc private func tapMoveToSignUpViewButton() {
-        let rootVC = SignUpViewController()
-        let navVC = UINavigationController(rootViewController: rootVC)
-        navVC.modalPresentationStyle = .fullScreen
-        present(navVC, animated: true)
-    }
-
-    func textFieldShouldReturn(_ textField: UITextField) -> Bool {
-        userNameTextField.resignFirstResponder()
-        return true
-    }
-
-    private func login() {
-        guard
-            let username = userNameTextField.text,
-            let password = passwordTextField.text
-        else {
-            return
-        }
+    private func bindViewModel() {
+
+        //input
+        userNameTextField.rx.text.orEmpty.asObservable()
+            .bind(to: viewModel.input.username)
+            .disposed(by: disposeBag)
+
+        passwordTextField.rx.text.orEmpty.asObservable()
+            .bind(to: viewModel.input.password)
+            .disposed(by: disposeBag)
 
-        authRepository.login(username: username, password: password)
-            .subscribe(on: SerialDispatchQueueScheduler(qos: .background))
-            .observe(on: MainScheduler.instance)
-            .subscribe( onSuccess: { [weak self] token in
-                guard let me = self else { return }
-                guard let authToken = token["token"] else { return }
-                me.keychainAccessRepository.save(token: authToken)
+        loginButton.rx.tap
+            .bind(to: Binder(self) { me, _ in
+                me.viewModel.input.loginButtonTapped()
+            })
+            .disposed(by: disposeBag)
+
+        //output
+        viewModel.output.loginSucceeded.asObservable()
+            .bind(to: Binder(self) { me, _ in
                 let rootVC = ListViewController()
                 let navVC = UINavigationController(rootViewController: rootVC)
                 navVC.modalPresentationStyle = .fullScreen
+                me.present(navVC, animated: true)
+            })
+            .disposed(by: disposeBag)
+
+        //サインアップ画面へ遷移
+        moveToSignUpViewButton.rx.tap.asDriver()
+            .drive(onNext: { [weak self] in
+                let rootVC = SignUpViewController()
+                let navVC = UINavigationController(rootViewController: rootVC)
+                navVC.modalPresentationStyle = .fullScreen
                 self?.present(navVC, animated: true)
-            },
-            onFailure: { error in
-                guard let error = error as? APIError else { return }
-                switch error {
-                case .decode(let error):
-                    print(error)
-                case .network(let error):
-                    print(error)
-                case .unknown(let error):
-                    print(error)
-                case .noResponse:
-                    print("No Response")
-                }
             })
             .disposed(by: disposeBag)
     }
+
+    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
+        self.view.endEditing(true)
+    }
+
+    func textFieldShouldReturn(_ textField: UITextField) -> Bool {
+        userNameTextField.resignFirstResponder()
+        return true
+    }
 }

hack_iOS/Sources/ViewModel/LoginViewModel.swift

@@ -6,7 +6,91 @@
 //
 
 import Foundation
+import RxSwift
+import RxCocoa
 
-class LoginViewModel {
+protocol LoginViewModelType {
+    var input: LoginViewModelInput { get }
+    var output: LoginViewModelOutput { get }
+}
+
+protocol LoginViewModelInput {
+    var username: BehaviorRelay<String> { get }
+    var password: BehaviorRelay<String> { get }
+    func loginButtonTapped()
+    func moveToSignUpButtonTapped()
+}
+
+protocol LoginViewModelOutput {
+    var loginSucceeded: Signal<Void> { get }
+}
+
+final class LoginViewModel: LoginViewModelType, LoginViewModelInput, LoginViewModelOutput {
+
+    struct Dependency {
+        var authrepository: AuthRepository
+        var keychainAccessRepository: KeychainAccessRepository
+    }
+
+    let username = BehaviorRelay<String>(value: "")
+    let password = BehaviorRelay<String>(value: "")
+
+    private let loginButtonTappedRelay = PublishRelay<Void>()
+    private let moveToSignUpButtonTappedRelay = PublishRelay<Void>()
+
+    private let loginSucceededRelay = PublishRelay<Void>()
+    var loginSucceeded: Signal<Void> {
+        loginSucceededRelay.asSignal()
+    }
+
+    private let dependency: Dependency
+    private let disposeBag = DisposeBag()
+
+    var input: LoginViewModelInput { self }
+    var output: LoginViewModelOutput { self }
+
+    init(dependency: Dependency) {
+        self.dependency = dependency
+
+        let loginEvent = loginButtonTappedRelay.asObservable()
+            .withLatestFrom(username)
+            .withLatestFrom(password) { ($0, $1) } // optionalの場合はエラーを吐く....
+            .filter { username, password in
+                !username.isEmpty && !password.isEmpty
+            }
+            .flatMap { username, password in
+                dependency.authrepository.login(username: username, password: password)
+                    .asObservable().materialize()
+            }
+            .share()
+
+        loginEvent
+            .flatMap { $0.element.map(Observable.just) ?? .empty() }
+            .subscribe( Binder(self) { me, token in
+                guard let authToken = token["token"] else { return }
+                me.dependency.keychainAccessRepository.save(token: authToken)
+                me.loginSucceededRelay.accept(())
+            })
+            .disposed(by: disposeBag)
+
+        loginEvent
+            .flatMap { $0.error.map(Observable.just) ?? .empty() }
+            .subscribe( Binder(self) { _, error in
+                guard let error = error as? APIError else { return }
+                switch error {
+                case .decode(let error):
+                    print(error)
+                case .network(let error):
+                    print(error)
+                case .unknown(let error):
+                    print(error)
+                case .noResponse:
+                    print("No Response")
+                }
+            })
+            .disposed(by: disposeBag)
+    }
 
+    func loginButtonTapped() { loginButtonTappedRelay.accept(()) }
+    func moveToSignUpButtonTapped() { moveToSignUpButtonTappedRelay.accept(()) }
 }