Nil in OpenWeather API - ios

Question

I've just started to learn Swift and iOS and I have problem in my weather app. I'm trying to get weather data and print in console, but there is still nil and I no have idea what could be wrong. I tried to change the model, pasted all url and is still nil. Sometimes app sends data and there is no answer, but at other times is answer or no sending, no answer. In console always nil...
Generated model class:
import Foundation
class CurrentWeather : NSObject, NSCoding{
var base : String!
var clouds : Cloud!
var cod : Int!
var coord : Coord!
var dt : Int!
var id : Int!
var main : Main!
var name : String!
var sys : Sy!
var visibility : Int!
var weather : [Weather]!
var wind : Wind!
/**
* Instantiate the instance using the passed dictionary values to set the properties values
*/
init(fromDictionary dictionary: [String:Any]){
base = dictionary["base"] as? String
cod = dictionary["cod"] as? Int
dt = dictionary["dt"] as? Int
id = dictionary["id"] as? Int
name = dictionary["name"] as? String
visibility = dictionary["visibility"] as? Int
if let cloudsData = dictionary["clouds"] as? [String:Any]{
clouds = Cloud(fromDictionary: cloudsData)
}
if let coordData = dictionary["coord"] as? [String:Any]{
coord = Coord(fromDictionary: coordData)
}
if let mainData = dictionary["main"] as? [String:Any]{
main = Main(fromDictionary: mainData)
}
if let sysData = dictionary["sys"] as? [String:Any]{
sys = Sy(fromDictionary: sysData)
}
if let windData = dictionary["wind"] as? [String:Any]{
wind = Wind(fromDictionary: windData)
}
weather = [Weather]()
if let weatherArray = dictionary["weather"] as? [[String:Any]]{
for dic in weatherArray{
let value = Weather(fromDictionary: dic)
weather.append(value)
}
}
}
/**
* Returns all the available property values in the form of [String:Any] object where the key is the approperiate json key and the value is the value of the corresponding property
*/
func toDictionary() -> [String:Any]
{
var dictionary = [String:Any]()
if base != nil{
dictionary["base"] = base
}
if cod != nil{
dictionary["cod"] = cod
}
if dt != nil{
dictionary["dt"] = dt
}
if id != nil{
dictionary["id"] = id
}
if name != nil{
dictionary["name"] = name
}
if visibility != nil{
dictionary["visibility"] = visibility
}
if clouds != nil{
dictionary["clouds"] = clouds.toDictionary()
}
if coord != nil{
dictionary["coord"] = coord.toDictionary()
}
if main != nil{
dictionary["main"] = main.toDictionary()
}
if sys != nil{
dictionary["sys"] = sys.toDictionary()
}
if wind != nil{
dictionary["wind"] = wind.toDictionary()
}
if weather != nil{
var dictionaryElements = [[String:Any]]()
for weatherElement in weather {
dictionaryElements.append(weatherElement.toDictionary())
}
dictionary["weather"] = dictionaryElements
}
return dictionary
}
/**
* NSCoding required initializer.
* Fills the data from the passed decoder
*/
#objc required init(coder aDecoder: NSCoder)
{
base = aDecoder.decodeObject(forKey: "base") as? String
clouds = aDecoder.decodeObject(forKey: "clouds") as? Cloud
cod = aDecoder.decodeObject(forKey: "cod") as? Int
coord = aDecoder.decodeObject(forKey: "coord") as? Coord
dt = aDecoder.decodeObject(forKey: "dt") as? Int
id = aDecoder.decodeObject(forKey: "id") as? Int
main = aDecoder.decodeObject(forKey: "main") as? Main
name = aDecoder.decodeObject(forKey: "name") as? String
sys = aDecoder.decodeObject(forKey: "sys") as? Sy
visibility = aDecoder.decodeObject(forKey: "visibility") as? Int
weather = aDecoder.decodeObject(forKey: "weather") as? [Weather]
wind = aDecoder.decodeObject(forKey: "wind") as? Wind
}
/**
* NSCoding required method.
* Encodes mode properties into the decoder
*/
#objc func encode(with aCoder: NSCoder)
{
if base != nil{
aCoder.encode(base, forKey: "base")
}
if clouds != nil{
aCoder.encode(clouds, forKey: "clouds")
}
if cod != nil{
aCoder.encode(cod, forKey: "cod")
}
if coord != nil{
aCoder.encode(coord, forKey: "coord")
}
if dt != nil{
aCoder.encode(dt, forKey: "dt")
}
if id != nil{
aCoder.encode(id, forKey: "id")
}
if main != nil{
aCoder.encode(main, forKey: "main")
}
if name != nil{
aCoder.encode(name, forKey: "name")
}
if sys != nil{
aCoder.encode(sys, forKey: "sys")
}
if visibility != nil{
aCoder.encode(visibility, forKey: "visibility")
}
if weather != nil{
aCoder.encode(weather, forKey: "weather")
}
if wind != nil{
aCoder.encode(wind, forKey: "wind")
}
}
}
WeatherService:
import Foundation
class WeatherSerice {
let weatherAPIKey: String
let weatherBaseURL: URL?
init(APIKey: String) {
self.weatherAPIKey = APIKey
weatherBaseURL = URL(string: "https://api.openweathermap.org/data/2.5/weather?")
}
func getCurrentWeather(city: String, completion: #escaping (CurrentWeather?) -> Void) {
if let weatherURL = URL(string: "\(weatherBaseURL!)q=\(city)&appid=\(weatherAPIKey)") {
let networkProcessor = NetworkProcessor(url: weatherURL)
networkProcessor.downloadJSONFromURL({(jsonDictionary) in
if let currentWeatherDictionary = jsonDictionary?["currently"] as?
[String : Any] {
let currentWeather = CurrentWeather(fromDictionary: currentWeatherDictionary)
completion(currentWeather)
} else {
completion(nil)
}
})
}
}
}
Part of the UIViewController:
let weatherService = WeatherSerice(APIKey: "52e6ff60bba8613b4850e065dcd3d0ac")
weatherService.getCurrentWeather(city: "London") {
(currentWeather) in
print (currentWeather)
}

Answer 1

Please, please drop NSCoding in favor of Codable, you will get rid of all that ugly boilerplate code
struct WeatherData : Decodable {
let coord : Coordinate
let cod, visibility, id : Int
let name : String
let base : String
let weather : [Weather]
let clouds: Clouds
let sys : Sys
let main : Main
let wind : Wind
let dt : Date
}
struct Coordinate : Decodable {
let lat, lon : Double
}
struct Weather : Decodable {
let id : Int
let icon : String
let main : MainEnum
let description: String
}
struct Sys : Decodable {
let type, id : Int
let sunrise, sunset : Date
let message : Double
let country : String
}
struct Main : Decodable {
let temp, tempMin, tempMax : Double
let pressure, humidity : Int
}
struct Wind : Decodable {
let speed : Double
let deg : Int
let gust : Double?
}
struct Clouds: Decodable {
let all: Int
}
enum MainEnum: String, Decodable {
case clear = "Clear"
case clouds = "Clouds"
case rain = "Rain"
}
As you can see the dates are decoded as Date and the main values in Weather are decoded as enum.
I don't know the API NetworkProcessor so I replaced it with traditional URLSession. The added URLComponents provide proper URL encoding for example if the city contains space characters
import Foundation
class WeatherSerice {
let weatherAPIKey: String
let weatherBase = "https://api.openweathermap.org/data/2.5/weather"
init(APIKey: String) {
self.weatherAPIKey = APIKey
}
func getCurrentWeather(city: String, completion: #escaping (WeatherData?) -> Void) {
var urlComponents = URLComponents(string: weatherBase)!
let queryItems = [URLQueryItem(name: "q", value: city),
URLQueryItem(name: "appid", value: weatherAPIKey)]
urlComponents.queryItems = queryItems
if let weatherURL = urlComponents.url {
let task = URLSession.shared.dataTask(with: weatherURL) { (data, response, error) in
if let error = error { print(error); completion(nil) }
do {
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
decoder.dateDecodingStrategy = .secondsSince1970
let result = try decoder.decode(WeatherData.self, from: data!)
completion(result)
} catch {
print(error)
completion(nil)
}
}
task.resume()
}
}
}
I recommend to use the new Result type in Swift 5 to return the error, too.
func getCurrentWeather(city: String, completion: #escaping (Result<WeatherData,Error>) -> Void) {
var urlComponents = URLComponents(string: weatherBase)!
let queryItems = [URLQueryItem(name: "q", value: city),
URLQueryItem(name: "appid", value: weatherAPIKey)]
urlComponents.queryItems = queryItems
if let weatherURL = urlComponents.url {
let task = URLSession.shared.dataTask(with: weatherURL) { (data, response, error) in
if let error = error { completion(.failure(error)) }
do {
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
decoder.dateDecodingStrategy = .secondsSince1970
let result = try decoder.decode(WeatherData.self, from: data!)
completion(.success(result))
} catch {
completion(.failure(error))
}
}
task.resume()
}
and use it
weatherService.getCurrentWeather(city: "London") { result in
switch result {
case .success(let result): print(result)
case .failure(let error): print(error)
}
}