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實時傳播遠程配置更新

使用遠程配置後台觸發功能提供了火力地堡雲功能連同FCM ,您可以遠程配置傳播實時更新。在這種情況下,您創建一個函數,該函數在您從儀表板或 API 發布或回滾遠程配置模板時觸發。模板更新觸發函數發送 FCM 消息,讓客戶端知道他們現有的配置已經過時,他們的下一次獲取應該來自服務器:

顯示通過 Cloud Functions 觸發 FCM 警報的遠程配置更新的圖表

本文檔的其餘部分將引導您完成這些步驟以實時傳播遠程配置更新。

將客戶端應用程序實例訂閱到 FCM 主題

要將 FCM 消息定位到大量客戶端應用程序實例(例如您的整個用戶群),主題消息傳遞是最有效的機制。應接收的實時遠程配置更新每個應用程序實例必須訂閱喜歡的主題名稱,例如, PUSH_RC

迅速

extension AppDelegate : MessagingDelegate {
    func messaging(_ messaging: Messaging, didReceiveRegistrationToken fcmToken: String) {
        messaging.subscribe(toTopic: "PUSH_RC") { error in
            print("Subscribed to PUSH_RC topic")
        }
    }
}
    

目標-C

- (void)messaging:(FIRMessaging *)messaging didReceiveRegistrationToken:(NSString *)fcmToken {
    [[FIRMessaging messaging] subscribeToTopic:@"PUSH_RC" completion:^(NSError * _Nullable error) {
        NSLog(@"Subscribed to PUSH_RC topic");
    }];
}
    

安卓

@Override
public void onNewToken(String s) {
    FirebaseMessaging.getInstance().subscribeToTopic("PUSH_RC");
}
    

創建一個函數以在模板更新時發送 FCM ping

您可以觸發功能以響應遠程配置事件,包括發布新配置版本或回滾到舊版本。要實時傳播模板更新,請創建一個偵聽模板發布事件的函數,然後使用您函數中的 FCM Admin SDK 向客戶端應用程序實例發送靜默 ping:

exports.pushConfig = functions.remoteConfig.onUpdate(versionMetadata => {
  // Create FCM payload to send data message to PUSH_RC topic.
  const payload = {
    topic: "PUSH_RC",
    data: {
      "CONFIG_STATE": "STALE"
    }
  };
  // Use the Admin SDK to send the ping via FCM.
  return admin.messaging().send(payload).then(resp => {
    console.log(resp);
    return null;
  });
});

這個函數設置一個CONFIG_STATE參數,然後發送,作為一個FCM消息給所有客戶端的數據有效載荷訂閱的PUSH_RC主題。

在客戶端設置遠程配置狀態

在前面的步驟中所示的數據有效載荷始終將CONFIG_STATESTALE在應用程序的共享偏好。這表明已經存儲在應用程序中的遠程配置模板現在已經過時,因為創建了新的、更新的模板,其發布觸發了該功能。更新您的通知處理程序以測試此條件:

迅速

func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any],
                 fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {

    if (userInfo.index(forKey: "CONFIG_STATE") != nil) {
        print("Config set to stale")
        UserDefaults.standard.set(true, forKey:"CONFIG_STALE")
    }

    completionHandler(UIBackgroundFetchResult.newData)
}
    

目標-C

- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo
fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler {

    if (userInfo[@"CONFIG_STATE"]) {
        NSLog(@"Config set to stale");
        [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"CONFIG_STALE"];
    }

    completionHandler(UIBackgroundFetchResultNewData);
}
    

安卓

@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
    if (remoteMessage.getData().containsKey("CONFIG_STATE")) {
        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
        sharedPreferences.edit().putBoolean("CONFIG_STALE", true).apply();
    }
}
    

在應用程序啟動時獲取遠程配置更新

迅速

func fetchConfig() {
  welcomeLabel.text = remoteConfig[loadingPhraseConfigKey].stringValue

  var expirationDuration = 3600
  // If your app is using developer mode, expirationDuration is set to 0, so each fetch will
  // retrieve values from the service.
  if remoteConfig.configSettings.isDeveloperModeEnabled || UserDefaults.standard.bool(forKey: "CONFIG_STALE") {
    expirationDuration = 0
  }

  remoteConfig.fetch(withExpirationDuration: TimeInterval(expirationDuration)) { (status, error) -> Void in
    if status == .success {
      print("Config fetched!")
      self.remoteConfig.activateFetched()
    } else {
      print("Config not fetched")
      print("Error: \(error?.localizedDescription ?? "No error available.")")
    }
    self.displayWelcome()
  }
}
    

目標-C

- (void)fetchConfig {
    self.welcomeLabel.text = self.remoteConfig[kLoadingPhraseConfigKey].stringValue;

    long expirationDuration = 3600;
    // If your app is using developer mode, expirationDuration is set to 0, so each fetch will
    // retrieve values from the Remote Config service.
    if (self.remoteConfig.configSettings.isDeveloperModeEnabled || [[NSUserDefaults standardUserDefaults] boolForKey:@"CONFIG_STALE"]) {
        expirationDuration = 0;
    }

    [self.remoteConfig fetchWithExpirationDuration:expirationDuration completionHandler:^(FIRRemoteConfigFetchStatus status, NSError *error) {
        if (status == FIRRemoteConfigFetchStatusSuccess) {
            NSLog(@"Config fetched!");
            [self.remoteConfig activateFetched];
            [[NSUserDefaults standardUserDefaults] setBool:NO forKey:@"CONFIG_STALE"];
        } else {
            NSLog(@"Config not fetched");
            NSLog(@"Error %@", error.localizedDescription);
        }
        [self displayWelcome];
    }];
}
    

安卓

private void fetchWelcomeMessage() {
    mWelcomeTextView.setText(mFirebaseRemoteConfig.getString("loading_phrase"));

    long cacheExpiration = 43200; // 12 hours in seconds.
    // If your app is using developer mode or cache is stale, cacheExpiration is set to 0,
    // so each fetch will retrieve values from the service.
    if (mFirebaseRemoteConfig.getInfo().getConfigSettings().isDeveloperModeEnabled() ||
            mSharedPreferences.getBoolean("CONFIG_STALE", false)) {
        cacheExpiration = 0;
    }

    mFirebaseRemoteConfig.fetch(cacheExpiration)
            .addOnCompleteListener(this, new OnCompleteListener<Void>() {
                @Override
                public void onComplete(@NonNull Task<Void> task) {
                    if (task.isSuccessful()) {
                        Toast.makeText(MainActivity.this, "Fetch Succeeded",
                                Toast.LENGTH_SHORT).show();

                        // After config data is successfully fetched, it must be activated before newly fetched
                        // values are returned.
                        mFirebaseRemoteConfig.activateFetched();
                    } else {
                        Toast.makeText(MainActivity.this, "Fetch Failed",
                                Toast.LENGTH_SHORT).show();
                    }
                    mWelcomeTextView.setText(mFirebaseRemoteConfig.getString("welcome_message"));
                }
            });
}
    

最後,添加邏輯,你的應用程序來強制遠程配置從網絡(忽略本地存儲)獲取,因為CONFIG_STATESTALE 。如果您的應用從網絡獲取數據過於頻繁,則可能會受到 Firebase 的限制。見節流