Merge pull request #9 from justbcuz/anonymous-sign-in

Anonymous Sign In

Sources/SwiftfulFirebaseAuth/Core/AuthManager.swift

@@ -99,6 +99,17 @@ public final class AuthManager {
         return value
     }
 
+    public func signInAnonymously() async throws -> (user: UserAuthInfo, isNewUser: Bool) {
+        let value = try await provider.authenticateUser_Anonymously()
+        currentUser = AuthInfo(profile: value.user)
+
+        defer {
+            streamSignInChangesIfNeeded()
+        }
+
+        return value
+    }
+
     public func signInPhone_Start(phoneNumber: String) async throws {
         try await provider.authenticateUser_PhoneNumber_Start(phoneNumber: phoneNumber)
     }

Sources/SwiftfulFirebaseAuth/Core/SignInAnonymousButtonView.swift

@@ -0,0 +1,97 @@
+//
+//  SignInAnonymousButtonView.swift
+//
+//
+//  Created by Nick Sarno on 5/11/24.
+//
+
+import SwiftUI
+import SwiftUI
+import AuthenticationServices
+
+// TODO: Streamline all Sign In Buttons
+// Note: Most Anonymous sign-in should happen in the background and not be a button the user clicks.
+
+public struct SignInAnonymousButtonView: View {
+
+    private var backgroundColor: Color
+    private var foregroundColor: Color
+    private var borderColor: Color
+    private var buttonText: String
+    private var cornerRadius: CGFloat
+
+    public init(
+        type: ASAuthorizationAppleIDButton.ButtonType = .signIn,
+        style: ASAuthorizationAppleIDButton.Style = .black,
+        cornerRadius: CGFloat = 10
+    ) {
+        self.cornerRadius = cornerRadius
+        self.backgroundColor = style.backgroundColor
+        self.foregroundColor = style.foregroundColor
+        self.borderColor = style.borderColor
+        self.buttonText = type.buttonText.removingWord(" with")
+    }
+
+    public var body: some View {
+        ZStack {
+            RoundedRectangle(cornerRadius: cornerRadius)
+                .fill(borderColor)
+
+            RoundedRectangle(cornerRadius: cornerRadius)
+                .fill(backgroundColor)
+                .padding(0.8)
+
+            HStack(spacing: 8) {
+                Image(systemName: "person.circle.fill")
+                    .resizable()
+                    .scaledToFit()
+                    .frame(width: 16, height: 16)
+
+                Text("\(buttonText) Anonymously")
+                    .font(.system(size: 21))
+                    .fontWeight(.medium)
+            }
+            .foregroundColor(foregroundColor)
+        }
+        .padding(.vertical, 1)
+        .disabled(true)
+    }
+}
+
+fileprivate extension String {
+    func removingWord(_ word: String) -> String {
+        let pattern = "\\b\(word)\\b"
+        return self.replacingOccurrences(of: pattern, with: "", options: .regularExpression)
+    }
+}
+
+#Preview("SignInAnonymousButtonView") {
+    VStack {
+        SignInWithAppleButtonView()
+            .frame(height: 60)
+            .padding()
+        SignInWithGoogleButtonView()
+            .frame(height: 60)
+            .padding()
+        SignInWithPhoneButtonView()
+            .frame(height: 60)
+            .padding()
+
+        if #available(iOS 14.0, *) {
+            SignInAnonymousButtonView(type: .signUp)
+                .frame(height: 60)
+                .padding()
+        }
+
+        SignInAnonymousButtonView(type: .continue)
+            .frame(height: 60)
+            .padding()
+
+        SignInAnonymousButtonView(type: .signIn)
+            .frame(height: 60)
+            .padding()
+        SignInAnonymousButtonView(type: .default)
+            .frame(height: 60)
+            .padding()
+    }
+}

Sources/SwiftfulFirebaseAuth/Providers/AuthProvider.swift

@@ -11,6 +11,7 @@ import FirebaseAuth
 public protocol AuthProvider {
     func getAuthenticatedUser() -> UserAuthInfo?
     func authenticationDidChangeStream() -> AsyncStream<UserAuthInfo?>
+    func authenticateUser_Anonymously() async throws -> (user: UserAuthInfo, isNewUser: Bool)
     func authenticateUser_Google(GIDClientID: String) async throws -> (user: UserAuthInfo, isNewUser: Bool)
     func authenticateUser_Apple() async throws -> (user: UserAuthInfo, isNewUser: Bool)
     func authenticateUser_PhoneNumber_Start(phoneNumber: String) async throws
@@ -62,7 +63,7 @@ public struct UserAuthInfo: Codable {
         self.uid = user.uid
         self.email = user.email
         self.isAnonymous = user.isAnonymous
-        self.authProviders = user.providerData.compactMap({ AuthProviderOption(rawValue: $0.providerID) })
+        self.authProviders = UserAuthInfo.createAuthProviders(rawValues: user.providerData, isAnonymous: user.isAnonymous)
         self.displayName = user.displayName
         self.firstName = UserDefaults.auth.firstName
         self.lastName = UserDefaults.auth.lastName
@@ -72,6 +73,17 @@ public struct UserAuthInfo: Codable {
         self.lastSignInDate = user.metadata.lastSignInDate
     }
 
+    static private func createAuthProviders(rawValues: [any UserInfo], isAnonymous: Bool) -> [AuthProviderOption] {
+        // Note: Firebase Anonymous auth does not return a string for Auth Provider. Here we catch that edge case.
+        var providers = rawValues.compactMap({ AuthProviderOption(rawValue: $0.providerID) })
+
+        if providers.isEmpty && isAnonymous {
+            providers.append(.anonymous)
+        }
+
+        return providers
+    }
+
     enum CodingKeys: String, CodingKey {
         case uid = "user_id"
         case email = "email"
@@ -88,6 +100,7 @@ public struct UserAuthInfo: Codable {
 }
 
 public enum AuthProviderOption: String, Codable {
+    case anonymous = "anonymous"
     case google = "google.com"
     case apple = "apple.com"
     case email = "password"

Sources/SwiftfulFirebaseAuth/Providers/FirebaseAuthProvider.swift

@@ -32,6 +32,21 @@ struct FirebaseAuthProvider: AuthProvider {
         }
     }
 
+    @MainActor
+    func authenticateUser_Anonymously() async throws -> (user: UserAuthInfo, isNewUser: Bool) {
+
+        // Sign in to Firebase
+        let authDataResult = try await Auth.auth().signInAnonymously()
+
+        // Determines if this is the first time this user is being authenticated
+        let isNewUser = authDataResult.additionalUserInfo?.isNewUser ?? true
+
+        // Convert to generic type
+        let user = UserAuthInfo(user: authDataResult.user)
+
+        return (user, isNewUser)
+    }
+
     @MainActor
     func authenticateUser_Apple() async throws -> (user: UserAuthInfo, isNewUser: Bool) {
         let helper = SignInWithAppleHelper()
@@ -47,7 +62,7 @@ struct FirebaseAuthProvider: AuthProvider {
             )
 
             // Sign in to Firebase
-            let authDataResult = try await signIn(credential: credential)
+            let authDataResult = try await signInOrLink(credential: credential)
 
             var firebaserUser = authDataResult.user
 
@@ -87,7 +102,7 @@ struct FirebaseAuthProvider: AuthProvider {
         let credential = GoogleAuthProvider.credential(withIDToken: googleResponse.idToken, accessToken: googleResponse.accessToken)
 
         // Sign in to Firebase
-        let authDataResult = try await signIn(credential: credential)
+        let authDataResult = try await signInOrLink(credential: credential)
 
         var firebaserUser = authDataResult.user
 
@@ -132,7 +147,7 @@ struct FirebaseAuthProvider: AuthProvider {
         let credential = PhoneAuthProvider.provider().credential(withVerificationID: verificationId, verificationCode: code)
 
         // Sign in to Firebase
-        let authDataResult = try await signIn(credential: credential)
+        let authDataResult = try await signInOrLink(credential: credential)
 
         let firebaserUser = authDataResult.user
 
@@ -160,8 +175,13 @@ struct FirebaseAuthProvider: AuthProvider {
     // MARK: PRIVATE
 
 
-    private func signIn(credential: AuthCredential) async throws -> AuthDataResult {
-        try await Auth.auth().signIn(with: credential)
+    private func signInOrLink(credential: AuthCredential) async throws -> AuthDataResult {
+        // If user is anonymous, attempt to link credential to existing account. On failure, fall-back to signIn to create a new account.
+        if let user = Auth.auth().currentUser, user.isAnonymous, let result = try? await user.link(with: credential) {
+            return result
+        }
+
+        return try await Auth.auth().signIn(with: credential)
     }
 
     private func updateUserProfile(displayName: String?, firstName: String?, lastName: String?, photoUrl: URL?) async throws -> User? {

Sources/SwiftfulFirebaseAuth/Providers/MockAuthProvider.swift

@@ -45,6 +45,11 @@ final class MockAuthProvider: AuthProvider {
         }
     }
 
+    func authenticateUser_Anonymously() async throws -> (user: UserAuthInfo, isNewUser: Bool) {
+        try? await Task.sleep(nanoseconds: 1_000_000_000)
+        return signInMockUser()
+    }
+
     func authenticateUser_Google(GIDClientID: String) async throws -> (user: UserAuthInfo, isNewUser: Bool) {
         try? await Task.sleep(nanoseconds: 1_000_000_000)
         return signInMockUser()