How to save remote notification data into Core Data(Database) from NotificationServiceExtension

Question

I have implemented NotificationServiceExtension in my target application, and it is working fine.

• Created AppgroupID

   lazy var persistentStoreCoordinator: NSPersistentStoreCoordinator? = {
  
       var coordinator: NSPersistentStoreCoordinator? = NSPersistentStoreCoordinator(managedObjectModel: self.managedObjectModel)
       let options = [
           NSMigratePersistentStoresAutomaticallyOption: true,
           NSInferMappingModelAutomaticallyOption: true
           ]
  
       let oldStoreUrl = self.applicationDocumentsDirectory.appendingPathComponent("Model.sqlite")
       let directory: NSURL = FileManager.default.containerURL(forSecurityApplicationGroupIdentifier: AppGroupID)! as NSURL
       let newStoreUrl = directory.appendingPathComponent("Model.sqlite")!
  
       var targetUrl : URL? = nil
       var needMigrate = false
       var needDeleteOld = false
  
  
       if FileManager.default.fileExists(atPath: oldStoreUrl.path){
          needMigrate = true
          targetUrl = oldStoreUrl
       }
       if FileManager.default.fileExists(atPath: newStoreUrl.path){
          needMigrate = false
          targetUrl = newStoreUrl
  
          if FileManager.default.fileExists(atPath: oldStoreUrl.path){
              needDeleteOld = true
          }
       }
       if targetUrl == nil {
          targetUrl = newStoreUrl
       }
  
       if needMigrate {
          do {
              try coordinator?.addPersistentStore(ofType: NSSQLiteStoreType, configurationName: nil, at: targetUrl!, options: options) 
              if let store = coordinator?.persistentStore(for: targetUrl!) {
                  do {
                      try coordinator?.migratePersistentStore(store, to: newStoreUrl, options: options, withType: NSSQLiteStoreType)
  
                  } catch let error {
                      print("migrate failed with error : \(error)")
                  }
              }
          } catch let error {
              //CrashlyticsHelper.reportCrash(err: error as NSError, strMethodName: "migrateStore")
              print(error)
          }
      }
  
      if needDeleteOld {
          self.deleteDocumentAtUrl(url: oldStoreUrl)
          self.deleteDocumentAtUrl(url: self.applicationDocumentsDirectory.appendingPathComponent("Model.sqlite-shm"))
          self.deleteDocumentAtUrl(url: self.applicationDocumentsDirectory.appendingPathComponent("Model.sqlite-wal"))
      }
  
      do {
          try coordinator!.addPersistentStore(ofType: NSSQLiteStoreType, configurationName: nil, at: targetUrl, options: options)
      } catch var error as NSError {
          coordinator = nil
          NSLog("Unresolved error \(error), \(error.userInfo)")
          abort()
      } catch {
          fatalError()
      }
      return coordinator
  
  }() 
  
    **EDIT:**
  
  lazy var applicationDocumentsDirectory: URL = {
  
  let urls = Foundation.FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
  return urls[urls.count-1]}()
  
  override func didReceive(_ request: UNNotificationRequest, withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void) {
  
   self.contentHandler = contentHandler
   bestAttemptContent = (request.content.mutableCopy() as? 
   UNMutableNotificationContent)
  
  if let bestAttemptContent = bestAttemptContent {
      // Modify the notification content here...
      print("Mutable Data %@",bestAttemptContent)
      bestAttemptContent.title = "\(bestAttemptContent.title)"
      //bestAttemptContent.title = "Notification"
  
       let apnsDic = bestAttemptContent.userInfo["aps"] as! NSDictionary
          // NotificationManager.sharedInstance.handlePushNotification(byUserTapped: true, content: apnsDic)
          contentHandler(bestAttemptContent)
  
  } }
  
    // Storing APNS dictionary into database from extension
  
    func handlePushNotification(byUserTapped : Bool,content : NSDictionary) {
  
   let moduelDataDic = content.mutableCopy() as! NSMutableDictionary
  
  let entity2 =  NSEntityDescription.entity(forEntityName: "TextMessage",
                                            in: CoreDataStorage.sharedInstance.mainQueueCtxt!)
  
  let textMsg = NSManagedObject(entity: entity2!,
                                insertInto: CoreDataStorage.sharedInstance.mainQueueCtxt) as? TextMessage
  
  let trimmedMessage = (moduelDataDic.object(forKey: "msgbody")! as AnyObject).trimmingCharacters(in: .whitespacesAndNewlines)
  
  textMsg?.message = trimmedMessage
  msgInfo?.toText = textMsg
  rosterInfo.time = composeMsgDate as Date
  rosterInfo.addToToMessageInfo(NSSet(object: msgInfo!))
  
  DispatchQueue.main.async {
  
      let context = CoreDataStorage.sharedInstance.mainQueueCtxt
      if let moc = context {
          if moc.hasChanges {
              do {
                  try moc.save()
              } catch {
                  let nserror = error as NSError
                  print("Could not save In NotficationManager \(nserror), \(nserror.userInfo)")
              }
          }
      }
  
  } }
  

  In application background mode here I am fetching data which are stored in above method of NotificationServiceExtension and in my result i can get data from manageObject table (messageInfo) but no any data into relationship "let setArray = rosterInfo?.toMessageInfo"

  let resultPredicate = NSPredicate(format: "messageID == %@", 
  moduelDataDic.object(forKey: "message_id")! as! CVarArg)
  
  let messageInfoAry = 
  self.fetchMessagesFromCoreDataWithPredicate(resultPredicate: 
  resultPredicate, sortDescriptorKey: "time", isAscending: true, 
  fetchLimit: false, managedContext: self.getManageObjectContext())
  if messageInfoAry.count > 0 {
  
  let rosterInfo = (messageInfoAry[0] as! MessageInfo).toRoster
  let msgInfo = messageInfoAry[0] as! MessageInfo
  
  // Here i don't see msgInfo in this relationship but after relaunching my application i can able to see that same object
  
  let setArray = rosterInfo?.toMessageInfo 
  

  Any help from anyone?

Answer 1

Try adding the following code to your AppDelegate class and test it.

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

    completionHandler(.newData)
    performSelector(inBackground: #selector(saveNewNotificationInBackground(userInfo:)), with: userInfo)
}

@objc func saveNewNotificationInBackground(userInfo: [AnyHashable: Any]) -> Void {
    //save notification using core data
}