parsing array of three objects from json - ios

Question

i have 3 objects (nationalities, services and packages) and i got them from a JSON response as 3 arrays of these objects.. and i want to parse them from the JSON response ...
Classes are:
struct Root2 : Decodable {
let nationalities : [Nationalities]
let services : [Services]
let packages : [Packages]
}
struct Packages : Decodable {
let id: Int
let name: String
let idService: Int
let nationality: String
let totalPrice: Int
let visitsPerWeek: Int
let excludedDays: String
let excludedShifts: String
let excludedDates: String
let extraVisits: Int
let dateEnabled: String
let dateDisabled: String
let allowedFrom: String
let allowedTo: String
let visitType: String
let createdAt: String?
let updatedAt: String?
}
struct Nationalities : Decodable{
let id: Int
let name: String
let createdAt: String?
let updatedAt: String?
}
struct Services : Decodable{
let id: Int
let name, description: String
let createdAt: String?
let updatedAt: String?
}
and i have for each one another class like:
class Service : NSObject, NSCoding {
var id: Int
var name, desc: String
var createdAt: String?
var updatedAt: String?
init(id: Int, name: String, desc: String) {
self.id = id
self.name = name
self.desc = desc
}
required convenience init(coder aDecoder: NSCoder) {
let id = aDecoder.decodeInteger(forKey: "id")
let name = aDecoder.decodeObject(forKey: "name") as! String
let desc = aDecoder.decodeObject(forKey: "desc") as! String
self.init(id: id, name: name, desc: desc)
}
func encode(with aCoder: NSCoder) {
aCoder.encode(id, forKey: "id")
aCoder.encode(name, forKey: "name")
aCoder.encode(desc, forKey: "desc")
}
}
and i'm using it like this:
func GetServicesPackagesNationalities(){
let link: String = "my link"
guard let url = URL(string: link) else {
print("Error: cannot create URL")
return
}
let urlRequest = URLRequest(url: url)
let config = URLSessionConfiguration.default
let session = URLSession(configuration: config)
let task = session.dataTask(with: urlRequest) {
(data, response, error) in
guard error == nil else {
print("error calling GET on /public/api/services")
print(error!)
return
}
guard let responseData = data else {
print("Error: did not receive data")
return
}
do {
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
let result = try decoder .decode(Root2.self, from: responseData)
var nationalities = [Nationality]()
for nationality in result.nationalities{
let newnationality = Nationality(id: nationality.id, name: nationality.name)
nationalities.append(newnationality)
print(newnationality.name)
}
var services = [Service]()
for service in result.services {
let newservice = Service(id: service.id, name: service.name, desc: service.description)
services.append(newservice)
print(newservice.name)
}
var packages = [Package]()
for package in result.packages{
let newpackage = Package(id: package.id, name: package.name, idService: package.idService, nationality: package.nationality, totalPrice: package.totalPrice, visitsPerWeek: package.visitsPerWeek, excludedDays: package.excludedDays, excludedShifts: package.excludedShifts, excludedDates: package.excludedDates, extraVisits: package.extraVisits ,dateEnabled: package.dateEnabled , dateDisabled: package.dateDisabled, allowedFrom: package.allowedFrom, allowedTo: package.allowedTo ,visitType: package.visitType)
packages.append(newpackage)
print(newpackage.name)
}
}catch {
print("error trying to convert data to JSON")
return
}
}
task.resume()
}
and i will always get this:
error trying to convert data to JSON
and my json is:
{
"nationalities": [
{
"id": 1,
"name": "Saudi Arabia",
"created_at": "2018-04-24 05:50:41",
"updated_at": "2018-04-24 06:35:29",
"deleted_at": null
},
{
"id": 2,
"name": "Bahrain",
"created_at": "2018-04-24 05:52:52",
"updated_at": "2018-04-24 05:52:52",
"deleted_at": null
},
],
"services": [
{
"id": 1,
"name": "Nad",
"description": "Nad ",
"created_at": null,
"updated_at": null,
"deleted_at": null
},
{
"id": 2,
"name": "Reay",
"description": "Re ",
"created_at": null,
"updated_at": null,
"deleted_at": null
},
],
"packages": [
{
"id": 1,
"name": "Gold Package",
"id_service": 1,
"nationality": "4",
"total_price": 1000,
"visits_per_week": 2,
"excluded_weekdays": "null",
"excluded_shifts": "null",
"excluded_dates": "1111-11-11",
"extra_visits": 1,
"date_enabled_from": "2018-04-01",
"date_enabled_to": "2018-04-30",
"date_allowed_from": "2018-04-05",
"date_allowed_to": "2018-04-30",
"visit_type": "Multi",
"created_at": "2018-04-26 11:18:45",
"updated_at": "2018-04-26 11:18:45",
"deleted_at": null
}
]
}
i don't know what i'm doing wrong .. since i tried the same with two objects and worked fine ..
can someone please tell me what im doing wrong?
using them in userdefaults:
storing:
let userDefaults = UserDefaults.standard
let encodedData: Data = NSKeyedArchiver.archivedData(withRootObject: services)
userDefaults.set(encodedData, forKey: "services")
userDefaults.synchronize()
retrieving:
let decoded = userDefaults.object(forKey: "services") as! Data
let decodedService = NSKeyedUnarchiver.unarchiveObject(with: decoded) as! [Service]
for service in decodedService {
print(service.name)
}

Answer 1

Please never ever print a meaningless literal string in a catch clause, print always the actual error, it tells you exactly what's wrong
} catch {
print(error)
}
In Package there are a lot of issues, here are the error messages (and the suggestions to fix them):
"No value associated with key CodingKeys(stringValue: \"excludedDays\", converted to excluded_days."
There is no key excluded_days in the JSON. Delete the property or declare it as optional (String?)
"No value associated with key CodingKeys(stringValue: \"dateEnabled\" converted to date_enabled."
The actual snake_case converted property is supposed to be dateEnabledFrom
"No value associated with key CodingKeys(stringValue: \"dateDisabled\" converted to date_disabled."
There is no key date_disabled in the JSON. Delete the property or declare it as optional (String?)
"No value associated with key CodingKeys(stringValue: \"allowedFrom\", intValue: nil) (\"allowedFrom\"), converted to allowed_from."
The actual snake_case converted property is supposed to be dateAllowedFrom
"No value associated with key CodingKeys(stringValue: \"allowedTo\", intValue: nil) (\"allowedTo\"), converted to allowed_to."
The actual snake_case converted property is supposed to be dateAllowedTo
Note:
Why do you use another extra classes for Nationality, Service, Package? They seem to be redundant. If you really need reference semantics decode the JSON into classes.

Answer 2

See the difference between Nationality and Nationalities
You should use Nationalities to parse your JSON response.
You should do like this, as you have declare Nationalities object in Root2
var nationalities = [Nationalities]()
for nationality in result.nationalities{
let newnationality = Nationalities(id: nationality.id, name: nationality.name)
nationalities.append(newnationality)
print(newnationality.name)
}
same for Services and Packages, Please find it.