keychain/TrustedPeersHelper/SetValueTransformer.swift

   1 import CoreData
   2 import Foundation
   3
   4 @objc(SetValueTransformer)
   5 class SetValueTransformer: ValueTransformer {
   6     override class func transformedValueClass() -> AnyClass {
   7         return NSData.self
   8     }
   9
  10     override class func allowsReverseTransformation() -> Bool {
  11         return true
  12     }
  13
  14     override func transformedValue(_ value: Any?) -> Any? {
  15         do {
  16             guard let value = value else { return nil }
  17             return try NSKeyedArchiver.archivedData(withRootObject: value, requiringSecureCoding: true)
  18         } catch {
  19             os_log("Failed to serialize a Set: %@", log: tplogDebug, type: .default, error as CVarArg)
  20             return nil
  21         }
  22     }
  23
  24     override func reverseTransformedValue(_ value: Any?) -> Any? {
  25         do {
  26             guard let dataOp = value as? Data? else { return nil }
  27             guard let data = dataOp else { return nil }
  28
  29             let unarchiver = try NSKeyedUnarchiver(forReadingFrom: data)
  30             return unarchiver.decodeObject(of: [NSSet.self], forKey: NSKeyedArchiveRootObjectKey)
  31         } catch {
  32             os_log("Failed to deserialize a purported Set: %@", log: tplogDebug, type: .default, error as CVarArg)
  33             return nil
  34         }
  35     }
  36
  37     static let name = NSValueTransformerName(rawValue: "SetValueTransformer")
  38 }