WWDC 2020: Sync a Core Data store with the CloudKit public database

  • Concepts (CoreData / CloudKit)
    • Objects - NSManagedObject / CKRecord
    • Models - NSManagedObjectModel / Schema
    • Stores 0 NSPersistentStore / CKRecordZone or CKDatabase
  • recordName and modifiedAt need to be added in CloudKit dashboard for public databases.
  • Good example for a public database would be a high score table.
  • Public database does not support push notifications, uses polling.
    • Polling only happens on launch or after 30 minutes, data is not always up to date.
  • Read/write access
    • For private databases, read/write/modify only when signed in.
    • For public databases, read available when not signed in, but write and modify need user to be signed in (some exceptions with modify)
  • canUpdateRecord used to check if records can be modified
  • canDeleteRecord will return false if record is stored in public database (changes won’t be propagated to other devices) - use something like isTrashed property on object.