Append Nested Objects in Parameters of multi-form Swift using Alamofire - json

Question

I am uploading multiple images as well as JSON data using "Content-type": "multipart/form-data"
my issue is, I have nested objects to pass to the parameters
I was looking for a solution, and what I find is nested data with an array of String or Int, not another custom object (I was struggling with it for so long)
struct Car: Codable{
var id :Int,
var name:String,
var address:String,
var new:Bool
var users:[User]
}
struct User: Codable{
var id :Int,
var name:String,
var address:String,
var age:Int
}
I wanted to convert the data to do a dictionary to use it as parameters
func addNewCae(newCar:Car, images:[UIImage]){
let encoder = JSONEncoder()
let jsonData = try! encoder.encode(newCar)
let test = convertStringToDictionary(text: jsonData)
print(test)
let headers: HTTPHeaders
headers = ["Content-type": "multipart/form-data",
"Content-Disposition" : "form-data"]
AF.upload(multipartFormData: { multipartFormData in
for imageData in images {
guard let imgData = imageData.pngData() else { return }
multipartFormData.append(imgData , withName: "images[]", fileName: "image.jpeg", mimeType: "image/jpeg")
}
for (key, value) in self.convertStringToDictionary(text: jsonData)! {
multipartFormData.append("\(value)".data(using: .utf8)!, withName: key)
}
},to: "\(url)", usingThreshold: UInt64.init(),
method: .post,
headers: headers).responseString{ response in
switch response.result {
case .success(let value):
print(value)
break
case .failure(let error):
print(error)
}
}
}
func convertStringToDictionary(data: Data) -> [String:AnyObject]? {
do {
let json = try JSONSerialization.jsonObject(with: data, options: .mutableContainers) as? [String:AnyObject]
return json
} catch {
print("Something went wrong")
}
return nil
}
As a request of my code: all the car fields are registered in the database except the users' field
(in reality, I have more fields than that)
Why the users' field is not added to the parameters?
Any idea?
The users filed normally be of type [[String: AnyObject]] in the parameters
here is the data after I convert it to a dictionary
Optional(["name":"whatever" , "address": "here", "users": <__NSArrayM 0x6000008e4f90>(
{
"name" = "hello";
"address" = "there";
"age" = 20;
},
{
"name" = "hi";
"address" = "location";
"age" = 25;
}
)
, "new": 0])
hope am clear enough, I can add any further code or information if needed to be clearer
Thanks
Update
I did the encoding manually so now I have a correct dictionary format of type [String: AnyObject] but one of them is nested :
["name":"whatever" , "address": "here", "users": [
[
"name" = "hello";
"address" = "there";
"age" = 20;
],
[
"name" = "hi";
"address" = "location";
"age" = 25;
]
]
, "new": 0]
BUT, still, the "users" field is not able to be read, I think because the parameters don't support that kind of type?
Anyone have any other idea how to deal with these nested objects?