How to get each data from JSON on Swift 3? - swift3

Question

I'm registering some data of user in database and after that the API returns others data in JSON usuario, like this:
And i'm trying to get idUsuario, nome and cpf from this JSON and print to see if they are correct, but they don't appear on console!
#IBAction func botaoSalvar(_ sender: Any) {
let nomeUsuario = self.campoUsuario.text;
let cpf = self.campoCPF.text;
let senha = self.campoSenha.text;
let parameters = ["nome": nomeUsuario, "cpf": cpf, "senha": senha, "method": "app-set-usuario"]
let urlPost = "http://easypasse.com.br/gestao/wsCadastrar.php"
guard let url = URL(string: urlPost) else { return }
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.addValue("application/json", forHTTPHeaderField: "Content-Type")
guard let httpBody = try? JSONSerialization.data(withJSONObject: parameters, options: []) else { return }
request.httpBody = httpBody
let session = URLSession.shared
session.dataTask(with: request) {
(data, response, error) in
if let data = data {
do {
let dadosJson = try JSONSerialization.jsonObject(with: data, options: JSONSerialization.ReadingOptions.mutableContainers) as AnyObject
if let usuario = json["usuario"] as? [String: Any] {
let idUsuario = usuario["idUsuario"] as? Int
let nome = usuario["nome"] as? String
let cpf = usuario["cpf"] as? Int
print(idUsuario as! Int, nome as! String, cpf as! Int)
}
} catch {
print(error)
}
}
}.resume()

Answer 1

The value for key usuario is an array, please notice the (, dictionary is {. Blame the owner of the service for singular / plural confusion 😉.
This is your code with a few swiftifications (native collection types and no never .mutableContainers):
if let data = data {
do {
if let dadosJson = try JSONSerialization.jsonObject(with: data) as? [String:Any],
let usuarios = dadosJson["usuario"] as? [[String:Any]] {
for usuario in usuarios {
if let nomeUsuario = usuario["nome"] as? String {
print(nomeUsuario)
}
if let idUsuario = usuario["idUsuario"] as? Int { // can also be `String`
print(idUsuario)
}
if let cpf = usuario["cpf"] as? Int { // can also be `String`
print(cpf)
}
}
}
} catch {
print(error)
}
}