Get an array through a closure. Swift - swift

Question

I am studying networking (Alamofire).
And in his pet project on Viper architecture.
I am making a get request and getting a to-do list from a local server.
The data is returned to me successfully.
But I just can't figure out how to get them and transfer them to Interactor...
I want my fetchToDos method to return an array. But I keep making mistakes.
func fetchToDos() -> [ToDo]? { // <- My mistake is clearly here
let request = Session.default.request("http://localhost:3003/")
request.responseDecodable(of: ToDos.self) { (response) in
switch response.result {
case .success(let tasks):
print("SUCCESS to FETCH JSON: \(tasks)")
case .failure(let error):
print("FAILED to FETCH JSON: \(error.localizedDescription)")
}
}
}

Answer 1

you are using an asynchronous function, and so one way to get something out
of it when it is finished, is to use a completion handler, something like this:
(note you need to do the error checking etc...before you can use this for real)
class ToDoNetworking {
func fetchToDos(completion: #escaping ([ToDo] -> Void)) { // <- try this
let request = Session.default.request("http://localhost:3003/")
request.responseDecodable(of: [ToDos].self) { (response) in
switch response.result {
case .success(let tasks):
print("SUCCESS to FETCH JSON: \(tasks)")
completion(tasks) // <-- assuming tasks is [ToDo]
case .failure(let error):
print("FAILED to FETCH JSON: \(error.localizedDescription)")
completion([])
}
}
}
}

Answer 2

What is the type of data being returned by the network call? If it's an array of ToDo objects and your ToDo object supports Codable, then it's likely you want:
request.responseDecodable(of: [ToDo].self)
you pass in the type of object that you want to decode, which it sounds like, is an array of ToDo objects, hence [ToDo].self.