Working with Realm and result JSON - ios

Question

I am new to realm and I am trying to use Realm in my project. Here I am trying to parse JSON and save it using realm. When I am trying to loop through the result array error occurs
'Attempting to modify object outside of a write transaction - call beginwritetransaction on an RLMRealm instance first'
This is the JSON result:
{"data":[{"id":1,"parent_id":0,"name":"JenniferMaenle","title":"Ms","phone":"","address":"Toled, ohio","email":"jlmaenle#aol.com","image":"44381525_2017.jpg","relation_id":5,"created_at":null,"updated_at":"2017-08-10 02:30:05"},{"id":2, "parent_id":1,"name":"Khadeeja","title":"","phone":"","address":"","email":"","image":"Khadeeja_2017-07-17.jpg","relation_id":2,"created_at":null,"updated_at":"2017-07-17 08:3:12"}]}
I am trying to parse JSON and save it in the Realm database. Here is my try:
class Person: Object {
dynamic var name = ""
dynamic var title = ""
dynamic var address = ""
}
override func viewDidLoad() {
super.viewDidLoad()
self.add()
}
func add(){
guard let data = dataFromFile("ServerData") else { return }
let persons = Person()
do {
if let json = try JSONSerialization.jsonObject(with: data) as? [String: AnyObject] {
if let data = json["data"] as? [[String:AnyObject]]{
for eachItem in data{
persons.name = eachItem["name"] as! String
persons.title = eachItem["title"] as! String
persons.address = eachItem["address"] as! String
try! realm.write {
realm.add(persons)
}
}
}
}
} catch {
print("Error deserializing JSON: \(error)")
}
}

Answer 1

Do not modify the persons object and add it to the realm again. The error you see is because you add persons to the realm and then edit it on the second iteration in the for eachItem in data again. Persons is already added to the realm in this iteration and you try to give it a new name outside a realm write transaction. That's why you see the error. It's better to create a new object for every person.
func add(){
guard let data = dataFromFile("ServerData") else { return }
do {
if let json = try JSONSerialization.jsonObject(with: data) as? [String: AnyObject] {
if let data = json["data"] as? [[String:AnyObject]]{
for eachItem in data{
let persons = Person()
persons.name = eachItem["name"] as! String
persons.title = eachItem["title"] as! String
persons.address = eachItem["address"] as! String
try! realm.write {
realm.add(persons)
}
}
}
}
} catch {
print("Error deserializing JSON: \(error)")
}
}

Answer 2

As the error indicates, you need to preform the transaction inside a write,
One option is to write each person individually:
for eachItem in data{
let person = Person()
person.name = eachItem["name"] as! String
person.title = eachItem["title"] as! String
person.address = eachItem["address"] as! String
try! realm.write {
realm.add(person)
}
}
Second option is to build an object and then write:
for eachItem in data{
let person = Person();
person.name = eachItem["name"] as! String
person.title = eachItem["title"] as! String
person.address = eachItem["address"] as! String
persons.add(person)
}
try! realm.write {
realm. append(persons)
}
You might need to make few changes to this, but this is the idea.