i have problem with my json response

When I use this func , I print all data corect

      URLSession.shared.dataTask(with: request) { data, response, error in
        if let data = data {
            if let jsonString = String(data: data, encoding: .utf8) {
                print(jsonString)
            }
        }
    } .resume()

i get this correct data:

"brand":"Lamborghini", "model":"Huracan", "color":"#0052ff" ,"registration":"K1TEST", "lat":50.244495, "lng":18.996143,

but when i am using JasonDecoder and Model struct

        URLSession.shared.dataTask(with: request) { data, response, error in
        guard let data = data else {
            return
        }
        do {
            let decoder = JSONDecoder()
            let carData = try decoder.decode([Model].self, from: data)
            print(carData)
        } catch {
            print(error)
        }
    } .resume()

Model:

struct Model : Codable {
let brand : String
let model : String
let color : String
let registration : String
let lat : Double
let lng : Double }

CodingKeys(stringValue: "lat", intValue: nil)], debugDescription: "Expected to decode Double but found a string/data instead."

I know that this is something wrong whit lat and lng data but i don't know how to fix it. Help

CodePudding user response：

let lat : String

try this. from the error itself we can understand that you are getting lat as string and you are trying to parse as to double. I think the same thing will happen for lng also, so try to parse accordingly

CodePudding user response：

The problem you have identified, where lat and lng can be Double and sometimes String, can be dealt with the following code, to decode lat and lng into a consistent Double.

struct Model : Identifiable, Codable, Hashable {
    let id: String  // <-- an id is very usefull in SwiftUI code
    let brand : String
    let model : String
    let color : String
    let registration : String
    let lat : Double
    let lng : Double
    
    enum CodingKeys: String, CodingKey {
        case brand,model,color,registration,lat,lng
        case id = "_id"
    }
    
    init(from decoder: Decoder) throws {
        let values = try decoder.container(keyedBy: CodingKeys.self)
        id = try values.decode(String.self, forKey: .id)
        brand = try values.decode(String.self, forKey: .brand)
        model = try values.decode(String.self, forKey: .model)
        color = try values.decode(String.self, forKey: .color)
        registration = try values.decode(String.self, forKey: .registration)
        
        // decode lat, when it comes as a String
        if let theString = try? values.decode(String.self, forKey: .lat),
            let latitude = Double(theString) {
            lat = latitude
        } else {
            lat = try values.decode(Double.self, forKey: .lat)
        }
        
        // decode lng, when it comes as a String
        if let theString = try? values.decode(String.self, forKey: .lng),
            let longitude = Double(theString) {
            lng = longitude
        } else {
            lng = try values.decode(Double.self, forKey: .lng)
        }
        
    }
}