如何处理React Native应用中未登录用户的推送通知及校验登录状态

Hey there! Let's tackle your two questions around push notifications with OneSignal in React Native—specifically handling unauthenticated users and ensuring we only send notifications to logged-in folks:

When users aren't logged in, their OneSignal player ID still exists, but it isn't linked to your app's user account. Here are a few practical strategies to handle this scenario:

• Temporarily store personalized notifications: If the notification is user-specific (like an order update or account alert), hold it on your backend until the user logs in and you can associate their player ID with their account. Once linked, you can send the queued notification.
• Send only generic notifications: For global announcements (like scheduled maintenance or app feature updates), it's safe to send to all player IDs—just make sure the content doesn't reference any user-specific data or require authentication to act on.
• Suppress notifications client-side: In your React Native app, you can intercept incoming notifications and choose not to display them if the user isn't logged in. Use OneSignal's foreground handler to implement this:

  OneSignal.setNotificationWillShowInForegroundHandler(notificationReceivedEvent => {
    const notification = notificationReceivedEvent.getNotification();
    // Replace with your app's actual login state check logic
    const isLoggedIn = checkUserAuthStatus();
  
    if (!isLoggedIn) {
      // Don't show the notification to unauthenticated users
      notificationReceivedEvent.complete(null);
      // Optional: Customize to show a login prompt instead
      // notification.title = "Log in to view this update";
      // notificationReceivedEvent.complete(notification);
    } else {
      // Proceed to show the notification to logged-in users
      notificationReceivedEvent.complete(notification);
    }
  });
  

• Skip sending from the backend: If your notifications should only reach logged-in users, your backend can skip sending to player IDs that aren't linked to a user account (more on this validation in the next section).

The core solution here is linking OneSignal's player ID to your app's user account. Here's how to implement this effectively:

• Link player ID to user account on login: When a user successfully logs into your React Native app, call OneSignal's setExternalUserId method to associate their app-specific user ID with their OneSignal player ID:

  // After successful login, get your app's internal user ID (e.g., from your auth system)
  const appUserId = currentUser.id.toString();
  // Link it to the user's OneSignal player ID
  OneSignal.setExternalUserId(appUserId);
  

• Unlink on logout: When the user logs out, remove the association to ensure future notifications aren't sent to this player ID for the now-logged-out user:

  OneSignal.removeExternalUserId();
  

• Validate before sending from backend:
  • Option 1: Send via external user ID: Instead of targeting player IDs directly, send notifications using the external user ID (your app's user ID) through OneSignal's API. This ensures only users who have logged in and linked their account will receive the notification.
  • Option 2: Check player ID association: If you need to send to a specific player ID, first fetch the player's details via OneSignal's API to check if an external_user_id exists. If it's null, the user isn't logged in—skip sending:

    # Example backend logic (pseudocode)
    def send_notification_to_player(player_id, message):
        # Fetch player details from OneSignal API
        player_response = onesignal_client.get_player(player_id)
        player_data = player_response.json()
    
        if not player_data.get("external_user_id"):
            # No linked user account—skip sending the notification
            return "Notification skipped: User not logged in"
        
        # Send the notification if the user is authenticated
        onesignal_client.send_notification(
            contents={"en": message},
            include_player_ids=[player_id]
        )
        return "Notification sent successfully"
    

  • Option 3: Maintain a mapping table: Keep a database table in your backend that maps player IDs to app user IDs. When users log in, update this table; when they log out, remove the entry. Before sending a notification, check if the player ID exists in this table—if not, don't send.

内容的提问来源于stack exchange，提问作者jhintstone