git.r.bdr.sh - rbdr/map/blob - Map/State/Persistence.swift

   1 import CoreData
   2
   3 struct PersistenceController {
   4   static let shared = PersistenceController()
   5
   6   static var preview: PersistenceController = {
   7     let result = PersistenceController(inMemory: true)
   8     let viewContext = result.container.viewContext
   9     for _ in 0..<10 {
  10       let newMap = Map(context: viewContext)
  11       newMap.uuid = UUID()
  12       newMap.createdAt = Date()
  13       newMap.title = "Map \(newMap.createdAt!.format())"
  14       newMap.content = ""
  15     }
  16     do {
  17       try viewContext.save()
  18     } catch {
  19       let nsError = error as NSError
  20       fatalError("Unresolved error \(nsError), \(nsError.userInfo)")
  21     }
  22     return result
  23   }()
  24
  25   let container: NSPersistentCloudKitContainer
  26
  27   init(inMemory: Bool = false) {
  28     container = NSPersistentCloudKitContainer(name: "Map")
  29
  30     container.viewContext.mergePolicy = NSMergeByPropertyObjectTrumpMergePolicy
  31     container.viewContext.automaticallyMergesChangesFromParent = true
  32
  33     if inMemory {
  34       container.persistentStoreDescriptions.first!.url = URL(fileURLWithPath: "/dev/null")
  35     }
  36     container.loadPersistentStores(completionHandler: { (storeDescription, error) in
  37       if let error = error as NSError? {
  38         fatalError("Unresolved error \(error), \(error.userInfo)")
  39       }
  40     })
  41   }
  42 }