在 SwiftUI 中使用 ASWebAuthentication

Question

在 SwiftUI 视图中进行身份验证时遇到一些问题。我正在使用 ASWebAuthentication 并且每当我运行我得到一个错误：

Cannot start ASWebAuthenticationSession without providing presentation context. Set presentationContextProvider before calling -start.

我正在创建一个 ViewController 并根据 but that answer doesn’t seem to be working for me. I’ve also found this reddit post 传递对场景委托 window 的引用，但我不太清楚他们是如何做到的在设置场景委托的 window 之前使用 window 初始化视图。

这是我用于 SwiftUI 视图的代码：

import SwiftUI
import AuthenticationServices

struct Spotify: View {
  var body: some View {
    Button(action: {
        self.authWithSpotify()
    }) {
        Text("Authorize Spotify")
    }
  }

  func authWithSpotify() {

    let authUrlString = "https://accounts.spotify.com/authorize?client_id=\(spotifyID)&response_type=code&redirect_uri=http://redirectexample.com/callback&scope=user-read-private%20user-read-email"
    guard let url = URL(string: authUrlString) else { return }

    let session = ASWebAuthenticationSession(
        url: url,
        callbackURLScheme: "http://redirectexample.com/callback",
        completionHandler: { callback, error in

            guard error == nil, let success = callback else { return }

            let code = NSURLComponents(string: (success.absoluteString))?.queryItems?.filter({ [=10=].name == "code" }).first

            self.getSpotifyAuthToken(code)
    })

    session.presentationContextProvider = ShimViewController()
    session.start()
  }

  func getSpotifyAuthToken(_ code: URLQueryItem?) {
    // Get Token
  }

}

struct Spotify_Previews: PreviewProvider {
  static var previews: some View {
    Spotify()
  }
}

class ShimViewController: UIViewController, ASWebAuthenticationPresentationContextProviding {
  func presentationAnchor(for session: ASWebAuthenticationSession) -> ASPresentationAnchor {
    return globalPresentationAnchor ?? ASPresentationAnchor()
  }
}

在 SceneDelegate 中：

var globalPresentationAnchor: ASPresentationAnchor? = nil

class SceneDelegate: UIResponder, UIWindowSceneDelegate {

var window: UIWindow?

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
    // Use this method to optionally configure and attach the UIWindow `window` to the provided UIWindowScene `scene`.
    // If using a storyboard, the `window` property will automatically be initialized and attached to the scene.
    // This delegate does not imply the connecting scene or session are new (see `application:configurationForConnectingSceneSession` instead).

    // Use a UIHostingController as window root view controller
    if let windowScene = scene as? UIWindowScene {
        let window = UIWindow(windowScene: windowScene)
        window.rootViewController = UIHostingController(rootView: Spotify())
        self.window = window
        window.makeKeyAndVisible()
    }

    globalPresentationAnchor =  window
}

知道如何让这项工作成功吗？

Answer 1

在实现 ASWebAuthenticationSession 之前，我曾运行做过类似的事情。我没有意识到的一件事是，您必须对会话变量有一个强引用。所以我会让你的 session 变量成为你的 class 的属性，看看是否能解决问题。我的意思的一小段：

// initialize as a property of the class
var session: ASWebAuthenticationSession?

func authWithSpotify() {
    let authUrlString = "https://accounts.spotify.com/authorize?client_id=\(spotifyID)&response_type=code&redirect_uri=http://redirectexample.com/callback&scope=user-read-private%20user-read-email"
    guard let url = URL(string: authUrlString) else { return }

    // assign session here
    session = ASWebAuthenticationSession(url: url, callbackURLScheme: "http://redirectexample.com/callback", completionHandler: { callback, error in

            guard error == nil, let success = callback else { return }

            let code = NSURLComponents(string: (success.absoluteString))?.queryItems?.filter({ [=10=].name == "code" }).first

            self.getSpotifyAuthToken(code)
    })

    session.presentationContextProvider = ShimViewController()
    session.start()
}

Answer 2

关于 reddit post，我让它按原样工作。我的误解是 AuthView 没有被用作 'interface' 视图。我为我的身份验证视图创建了一个普通的 SwiftUI 视图，并且我有一个按钮，其操作是创建 AuthView 的实例，并调用处理会话的函数。我将 globalPositionAnchor 存储在 @EnvironmentObject 中，但您也应该能够从全局变量中使用它。希望这对您有所帮助！

struct SignedOutView: View {
    @EnvironmentObject var contentManager: ContentManager

    var body: some View {
        VStack {
            Text("Title")
            .font(.largeTitle)

            Spacer()

            Button(action: {AuthProviderView(window: self.contentManager.globalPresentationAnchor!).signIn()}) {
                Text("Sign In")
                    .padding()
                    .foregroundColor(.white)
                    .background(Color.orange)
                    .cornerRadius(CGFloat(5))
                    .font(.headline)
            }.padding()
        }
    }
}

Answer 3

使用 BetterSafariView 中的 .webAuthenticationSession(isPresented:content) 修饰符，您可以轻松地在 SwiftUI 中启动 Web 身份验证会话。它不需要挂钩 SceneDelegate.

import SwiftUI
import BetterSafariView

struct SpotifyLoginView: View {
    
    @State private var showingSession = false
    
    var body: some View {
        Button("Authorize Spotify") {
            self.showingSession = true
        }
        .webAuthenticationSession(isPresented: $showingSession) {
            WebAuthenticationSession(
                url: URL(string: "https://accounts.spotify.com/authorize")!,
                callbackURLScheme: "myapp"
            ) { callbackURL, error in
                // Handle callbackURL
            }
        }
    }
}

Answer 4

罗尼 - 我运行遇到了同样的问题，但最终让 ShimController() 工作并避免了警告。我陷入了解决方案，但忘记实例化 class。在下面查找我的“<<”评论。现在身份验证正在工作并且回调正在像发条一样触发。唯一需要注意的是，我授权的是其他东西——不是 Spotify。

var session: ASWebAuthenticationSession?
var shimController = ShimViewController() // << instantiate your object here

func authWithSpotify() {
    let authUrlString = "https://accounts.spotify.com/authorize?client_id=\(spotifyID)&response_type=code&redirect_uri=http://redirectexample.com/callback&scope=user-read-private%20user-read-email"
    guard let url = URL(string: authUrlString) else { return }

    // assign session here
    session = ASWebAuthenticationSession(url: url, callbackURLScheme: "http://redirectexample.com/callback", completionHandler: { callback, error in

            guard error == nil, let success = callback else { return }

            let code = NSURLComponents(string: (success.absoluteString))?.queryItems?.filter({ [=10=].name == "code" }).first

            self.getSpotifyAuthToken(code)
    })

    session.presentationContextProvider = shimController // << then reference it here
    session.start()
}

在 SwiftUI 中使用 ASWebAuthentication

Using ASWebAuthentication in SwiftUI

xcode

swift

aswebauthenticationsession

swiftui