【Swift/Firebase】Cloud Messagingのテスト通知方法！FCM登録トークン取得

PodFile
pod 'FirebaseMessaging'

AppDelegate.swift
import UIKit
import FirebaseCore
import FirebaseMessaging // 追加 #1

@main
class AppDelegate: UIResponder, UIApplicationDelegate {

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        FirebaseApp.configure() 

        Messaging.messaging().delegate = self  // #2
        
        UNUserNotificationCenter.current().delegate = self 

        let authOptions: UNAuthorizationOptions = [.alert, .badge, .sound]
        UNUserNotificationCenter.current().requestAuthorization(
          options: authOptions,
          completionHandler: { _, _ in }
        )

        application.registerForRemoteNotifications() 

        return true
    }

    // 〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜〜
}

extension AppDelegate : UNUserNotificationCenterDelegate {} 
// 追加
extension AppDelegate: MessagingDelegate {} // #3

func application(_ application: UIApplication,
                  didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
    Messaging.messaging().apnsToken = deviceToken

    Messaging.messaging().token { token, error in
      if let error = error {
        print("Error fetching FCM registration token: \(error)")
      } else if let token = token {
        print("FCM registration token: \(token)")
      }
    }
}

import SwiftUI
import FirebaseCore
import GoogleMobileAds
import FirebaseMessaging

class AppDelegate: NSObject, UIApplicationDelegate {
    func application(_ application: UIApplication,
                     didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil) -> Bool {
        FirebaseApp.configure()
        
        Messaging.messaging().delegate = self
                
        UNUserNotificationCenter.current().delegate = self

        let authOptions: UNAuthorizationOptions = [.alert, .badge, .sound]
        UNUserNotificationCenter.current().requestAuthorization(
          options: authOptions,
          completionHandler: { _, _ in }
        )

        application.registerForRemoteNotifications()
        
        GADMobileAds.sharedInstance().start(completionHandler: nil)
        
        return true
    }
}

extension AppDelegate : UNUserNotificationCenterDelegate {}

extension AppDelegate: MessagingDelegate {
    
    func messaging(_ messaging: Messaging, didReceiveRegistrationToken fcmToken: String?) {
        Messaging.messaging().token { token, error in
          if let error = error {
            print("Error fetching FCM registration token: \(error)")
          } else if let token = token {
            print("FCM registration token: \(token)")
          }
        }
    }
    
    func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
        Messaging.messaging().apnsToken = deviceToken
    }
}

@main
struct プロジェクト名App: App {
    @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}