Swift - JSON Serialisation of an nested object - ios

Question

I have a object that is created from JSON (serialised). This object has an id property that represents another object stored in the system. How can I get the nested object during the serialisation?
import UIKit
class Person: Codable {
let firstName: String
let lastName: String
let addressId: String
let address: Address // How to create it during serialisation
private enum CodingKeys: String, CodingKey {
case firstName
case lastName
case addressId = "addressId"
}
init(firstName: String, lastName: String, addressId:String) {
self.firstName = firstName
self.lastName = lastName
self.addressId = addressId
}
required init(from decoder: Decoder) throws {
let values = try decoder.container(keyedBy: CodingKeys.self)
self.firstName = try values.decode(String.self, forKey: .firstName)
self.lastName = try values.decode(String.self, forKey: .lastName)
self.addressId = try? values.decode(URL.self, forKey: .addressId)
}
}
struct PersonsList : Codable {
let persons: [Person]
}
class Address {
static func getAddress(addressId: String) -> Address
{
//some code
return address
}
}

Answer 1

Do it with lazy property
EDIT
Option1
lazy var address:Address = { [unowned self] in
return Address.getAddress(addressId: self.addressId)
}()
Option 2
var adreess1:Address {
return Address.getAddress(addressId: self.addressId)
}

Answer 2

JSON
Assuming this is your json
let json = """
[
{
"firstName": "James",
"lastName": "Kirk",
"address": { "id": "efg" }
}
]
"""
Model
You can simplify how you define your model
struct Person: Codable {
let firstName: String
let lastName: String
let address: Address
struct Address: Codable {
let id: String
}
}
As you can see there is no need to write your custom init(:from)
From JSON to Data
To test it not we are going to transform the json into a Data value.
let data = json.data(using: .utf8)!
Decoding
And finally we can decode the data
if let persons = try? JSONDecoder().decode([Person].self, from: data) {
print(persons.first?.address.id)
}
Output
Optional("efg")