Getting API Data within Swift

Question

I'm trying to get some data from an API at the address https://api.coinmarketcap.com/v1/ticker/bitcoin/?convert=AUD

I've started a new playground within Xcode, and my code is as follows

let urlString = "https://api.coinmarketcap.com/v1/ticker/bitcoin/?convert=AUD"

let url = URL(string: urlString)
URLSession.shared.dataTask(with:url!) { (data, response, error) in
    if error != nil {
        print(error as Any)
    } else {
        do {
            
            let parsedData = try JSONSerialization.jsonObject(with: data!) as! [String:Any]
            let id = parsedData["id"] as! [String:Any]
            
            print(id)
            
        } catch let error as NSError {
            print(error)
        }
    }
    
    }.resume()

However the playground is returning no result. I am quite new to Swift, so some of the syntax may be a little off. Can anyone make a suggestion how to obtain the information obtained at the API address?

Answer 1

You need to import PlaygroundSupport and set needsIndefiniteExecution to true.
Also you have some errors in the code as the result is array and you are casting it into a dictionary [String : Any].
Use the following code:

import UIKit
import PlaygroundSupport

PlaygroundPage.current.needsIndefiniteExecution = true

let urlString = "https://api.coinmarketcap.com/v1/ticker/bitcoin/?convert=AUD"

let url = URL(string: urlString)
URLSession.shared.dataTask(with:url!) { (data, response, error) in
    if error != nil {
        print(error!.localizedDescription)
    } else {
        do {

            let parsedData = try JSONSerialization.jsonObject(with: data!) as! [[String : Any]]
            for item in parsedData
            {
                let id = item["id"] as! String
                print(id)
            }

        } catch let error as NSError {
            print(error.localizedDescription)
        }
    }

    }.resume()