code change : 3. Add Auth

MOB304/code/Complete/Landmarks/Landmarks/AppDelegate.swift

@@ -6,12 +6,66 @@ The application delegate.
 */
 
 import UIKit
+import Amplify
+import AmplifyPlugins
 
 @UIApplicationMain
 class AppDelegate: UIResponder, UIApplicationDelegate {
 
+    public let userData = UserData()
+
     func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
-        // Override point for customization after application launch.
+
+        do {
+            Amplify.Logging.logLevel = .info
+            try Amplify.add(plugin: AWSCognitoAuthPlugin())
+
+            try Amplify.configure()
+            print("Amplify initialized")
+
+            // load data when user is signedin
+            self.checkUserSignedIn()
+
+            // listen to auth events.
+            // see https://github.com/aws-amplify/amplify-ios/blob/master/Amplify/Categories/Auth/Models/AuthEventName.swift
+            _ = Amplify.Hub.listen(to: .auth) { (payload) in
+
+                switch payload.eventName {
+
+                case HubPayload.EventName.Auth.signedIn:
+                    print("==HUB== User signed In, update UI")
+
+                    self.updateUI(forSignInStatus: true)
+
+                    // if you want to get user attributes
+                    _ = Amplify.Auth.fetchUserAttributes() { (result) in
+                        switch result {
+                        case .success(let attributes):
+                            print("User attribtues - \(attributes)")
+                        case .failure(let error):
+                            print("Fetching user attributes failed with error \(error)")
+                        }
+                    }
+
+
+                case HubPayload.EventName.Auth.signedOut:
+                    print("==HUB== User signed Out, update UI")
+                    self.updateUI(forSignInStatus: false)
+
+                case HubPayload.EventName.Auth.sessionExpired:
+                    print("==HUB== Session expired, show sign in aui")
+                    self.updateUI(forSignInStatus: false)
+
+                default:
+                    //print("==HUB== \(payload)")
+                    break
+                }
+            }
+
+        } catch {
+            print("Failed to configure Amplify \(error)")
+        }
+
         return true
     }
 
@@ -31,6 +85,60 @@ class AppDelegate: UIResponder, UIApplicationDelegate {
         // If any sessions were discarded while the application was not running, this will be called shortly after application:didFinishLaunchingWithOptions.
         // Use this method to release any resources that were specific to the discarded scenes, as they will not return.
     }
+
+    // MARK: -- Authentication code
+    
+    // change our internal state, this triggers an UI update on the main thread
+    func updateUI(forSignInStatus : Bool) {
+        DispatchQueue.main.async() {
+            self.userData.isSignedIn = forSignInStatus
+        }
+    }
+
+    // when user is signed in, fetch its details
+    func checkUserSignedIn() {
 
-}
+        // every time auth status changes, let's check if user is signedIn or not
+        // updating userData will automatically update the UI
+        _ = Amplify.Auth.fetchAuthSession { (result) in
+
+            do {
+                let session = try result.get()
+                self.updateUI(forSignInStatus: session.isSignedIn)
+            } catch {
+                print("Fetch auth session failed with error - \(error)")
+            }
+
+        }
+    }
+
+    // signin with Cognito web user interface
+    public func authenticateWithHostedUI() {
 
+        print("hostedUI()")
+        _ = Amplify.Auth.signInWithWebUI(presentationAnchor: UIApplication.shared.windows.first!) { result in
+            switch result {
+            case .success(_):
+                print("Sign in succeeded")
+            case .failure(let error):
+                print("Sign in failed \(error)")
+            }
+        }
+    }
+
+    // signout globally
+    public func signOut() {
+
+        // https://docs.amplify.aws/lib/auth/signOut/q/platform/ios
+        let options = AuthSignOutRequest.Options(globalSignOut: true)
+        _ = Amplify.Auth.signOut(options: options) { (result) in
+            switch result {
+            case .success:
+                print("Successfully signed out")
+            case .failure(let error):
+                print("Sign out failed with error \(error)")
+            }
+        }
+    }
+
+}

MOB304/code/Complete/Landmarks/Landmarks/Info.plist

@@ -2,6 +2,19 @@
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
 <dict>
+
+    <!-- ADD AN ENTRY TO CFBundleURLTypes for Cognito Auth -->
+    <!-- IF YOU DO NOT HAVE CFBundleURLTypes, YOU CAN COPY THE WHOLE BLOCK BELOW -->
+    <key>CFBundleURLTypes</key>
+    <array>
+        <dict>
+            <key>CFBundleURLSchemes</key>
+            <array>
+                <string>landmarks</string>
+            </array>
+        </dict>
+    </array>
+
 	<key>CFBundleDevelopmentRegion</key>
 	<string>$(DEVELOPMENT_LANGUAGE)</string>
 	<key>CFBundleExecutable</key>

MOB304/code/Complete/Landmarks/Landmarks/LandingView.swift

@@ -0,0 +1,37 @@
+//
+//  LandingView.swift
+//  Landmarks
+
+// Landmarks/LandingView.swift
+
+import SwiftUI
+
+struct LandingView: View {
+    @ObservedObject public var user : UserData
+
+    var body: some View {
+
+        return VStack {
+            // .wrappedValue is used to extract the Bool from Binding<Bool> type
+            if (!$user.isSignedIn.wrappedValue) {
+
+                Button(action: {
+                            let app = UIApplication.shared.delegate as! AppDelegate
+                            app.authenticateWithHostedUI()
+                        }) {
+                    UserBadge().scaleEffect(0.5)
+                }
+
+            } else {
+                LandmarkList().environmentObject(user)
+            }
+        }
+    }
+}
+
+struct LandingView_Previews: PreviewProvider {
+    static var previews: some View {
+        let app = UIApplication.shared.delegate as! AppDelegate
+        return LandingView(user: app.userData)
+    }
+}

MOB304/code/Complete/Landmarks/Landmarks/LandmarkList.swift

@@ -7,6 +7,18 @@ A view showing a list of landmarks.
 
 import SwiftUI
 
+struct SignOutButton : View {
+    let app = UIApplication.shared.delegate as! AppDelegate
+
+    var body: some View {
+        NavigationLink(destination: LandingView(user: app.userData)) {
+            Button(action: { self.app.signOut() }) {
+                Text("Sign Out")
+            }
+        }
+    }
+}
+
 struct LandmarkList: View {
     @EnvironmentObject private var userData: UserData
 
@@ -29,6 +41,7 @@ struct LandmarkList: View {
                 }
             }
             .navigationBarTitle(Text("Landmarks"))
+            .navigationBarItems(trailing: SignOutButton())
         }
     }
 }

MOB304/code/Complete/Landmarks/Landmarks/Models/UserData.swift

@@ -1,14 +1,9 @@
-/*
-See LICENSE folder for this sample’s licensing information.
-
-Abstract:
-A model object that stores app data.
-*/
-
+// Landmarks/Models/UserData.swift
 import Combine
 import SwiftUI
 
 final class UserData: ObservableObject {
     @Published var showFavoritesOnly = false
     @Published var landmarks = landmarkData
+    @Published var isSignedIn : Bool = false
 }

MOB304/code/Complete/Landmarks/Landmarks/SceneDelegate.swift

@@ -11,7 +11,8 @@ import SwiftUI
 class SceneDelegate: UIResponder, UIWindowSceneDelegate {
 
     var window: UIWindow?
-
+    let app = UIApplication.shared.delegate as! AppDelegate
+
     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.
@@ -20,7 +21,9 @@ class SceneDelegate: UIResponder, UIWindowSceneDelegate {
         // Use a UIHostingController as window root view controller
         if let windowScene = scene as? UIWindowScene {
             let window = UIWindow(windowScene: windowScene)
-            window.rootViewController = UIHostingController(rootView: LandmarkList().environmentObject(UserData()))
+
+            window.rootViewController = UIHostingController(rootView: LandingView(user: app.userData))
+
             self.window = window
             window.makeKeyAndVisible()
         }
@@ -55,4 +58,3 @@ class SceneDelegate: UIResponder, UIWindowSceneDelegate {
     }
 
 }
-

MOB304/code/Complete/Landmarks/Landmarks/UserBadge.swift

@@ -0,0 +1,37 @@
+//
+//  UserBadge.swift
+//  Landmarks
+
+import SwiftUI
+
+struct UserBadge: View {
+    var body: some View {
+        GeometryReader { geometry in
+        ZStack {
+            Circle().stroke(Color.blue, lineWidth: geometry.size.width/50.0)
+
+            VStack {
+                Circle()
+                    .frame(width:geometry.size.width / 2.0, height:geometry.size.width / 2.0, alignment: .center)
+                    .foregroundColor(.blue)
+                    .offset(x:0, y:geometry.size.width/3.3)
+
+                Circle()
+                    .frame(width:geometry.size.width, height:geometry.size.width, alignment: .center)
+                    .foregroundColor(.blue)
+                    .offset(x:0, y:geometry.size.width/3.0)
+
+
+            }
+        }
+        .clipShape(Circle())
+        .shadow(radius: geometry.size.width/30.0)
+        }
+    }
+}
+
+struct UserBadge_Previews: PreviewProvider {
+    static var previews: some View {
+        UserBadge()
+    }
+}