AWS Cognito UserPool自定义登录保护AppClientSecret

Question

我看过链接（比如这个：https://aws.amazon.com/blogs/mobile/how-amazon-cognito-keeps-mobile-app-users-data-safe/），表示不将AppClientSecret存储在移动应用程序中但是如何实现自定义登录而不在应用程序中存储AppClientSecret？

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {

    let serviceConfiguration = AWSServiceConfiguration(region: .USEast1, credentialsProvider: nil)
    let userPoolConfiguration = AWSCognitoIdentityUserPoolConfiguration(clientId: CognitoIdentityUserPoolAppClientId, clientSecret: CognitoIdentityUserPoolAppClientSecret, poolId: CognitoIdentityUserPoolIdCognito)
    AWSCognitoIdentityUserPool.register(with: serviceConfiguration, userPoolConfiguration: userPoolConfiguration, forKey: AWSCognitoUserPoolsSignInProviderKey)
    pool = AWSCognitoIdentityUserPool(forKey: AWSCognitoUserPoolsSignInProviderKey)

    let credentialsProvider = AWSCognitoCredentialsProvider(regionType: .USEast1, identityPoolId: CognitoIdentityUserFederatedId, identityProviderManager:pool)
    let configuration = AWSServiceConfiguration(region:.USEast1, credentialsProvider:credentialsProvider)
    AWSServiceManager.default().defaultServiceConfiguration = configuration
    pool?.delegate = self
    return true
}