Parse local json file to object - ios

Question

I have this code:
struct ProductObject : Codable {
let palletHeight : Double?
let layerPallet : Int?
let prepCombisteamer : String?
let id : Int?
let avikoWorlds : [String]?
let avikoSegments : [String]?
let sunFlower : Bool?
let inPieces : Bool?
let noBox : Int?
let prepFryingPan : String?
let packageContents : Double?
let carbohydrates : Int?
let fat : Double?
let eanBox : Int?
let weightYieldPercent : Int?
let kcal : Int?
let markedAsFavourite1 : Bool?
let avikoPodSegmentyRynku : [String]?
let prepPot : String?
let prepMicrowave : String?
let name : String?
let code : Int?
let prepDeepFryer : String?
let avikoConcepts : [String]?
let boxLayer : Int?
let avikoSegmentyRynku : [String]?
let active : Bool?
let shelfLifeTimeFrame : String?
let markedAsFavourite2 : Bool?
let palletWeight : Double?
let changeTime : ChangeTime?
let kj : Int?
let langVersions : [LangVersions]?
let proteins : Double?
let markedAsFavourite3 : Bool?
let containsGluten : Bool?
let regions : [Int]?
let eanFoil : Int?
let shelfLife : Int?
let contentPerBox : Int?
let prepOven : String?
}
func downloadImagesFromJsonProductFile(fileName: URL){
let filePath = fileName.path
let fileManager = FileManager.default
if fileManager.fileExists(atPath: filePath) {
do {
let data = try Data(contentsOf: fileName)
let jsonData = try JSONDecoder().decode(ProductObject.self, from: data)
} catch let error {
self.errorLoginMessage(txt: "MainView - Error 109: Problem with parse file \(error)", title: "Blad".localized())
}
}
}
downloadImagesFromJsonProductFile(fileName: documentsDir.appendingPathComponent((AppGlobalManager.sharedManager.loggedUser?.selectedLanguage)! + "/json/products.json"))
My local json file: https://files.fm/u/73n845ty
When I run function: downloadImagesFromJsonProductFile I have error
(when app was started): Problem with parse file typeMismatch(Swift.Dictionary, Swift.DecodingError.Context(coding-path:[], debugDescription: "Expected the decode Dictionary but found an array instead.", underlyingError: will).
How to fix it?

Answer 1

As I review your JSON here http://json.parser.online.fr/, there is array as root object, therefore you should do
let json = try JSONDecoder().decode([ProductObject].self, from: data)
UPDATE
Please create JSON struct Codable from here json4swift, please resolve type mismatch errors first otherwise your JSON could not be parsed and you will get type Mismatch errors.
You can get product code by following,
let jsonData = try JSONDecoder().decode([ProductObject].self, from: data)
for detail in jsonData {
print(detail.code ?? "")
}