Codable.swift

    private func decodeObject<T: Codable>(key: String) -> T? {
        guard objectExist(key) else { return nil }
        let path = URL(fileURLWithPath: fullPath(key))
        do {
            let data = try Data(contentsOf: path)
            let decoder = PropertyListDecoder()
            let object = try decoder.decode(T.self, from: data)
            return object
        } catch {
            print("Decoding error: \(error)")
        }
        return nil
    }

    private func makeEncoder() -> PropertyListEncoder {
        let encoder = PropertyListEncoder()
        encoder.outputFormat = .binary
        return encoder
    }

    private func encodeObject<T: Codable>(object: T, key: String) {
        do {
            let encoder = self.makeEncoder()
            let data = try encoder.encode(object)
            let path = URL(fileURLWithPath: self.fullPath(key))
            try data.write(to: path, options: .atomic)
        } catch {
            print("Encoding error: \(error)")
        }
    }