You need to implement Do Try Catch error handling as follow:
import UIKit
import PlaygroundSupport
PlaygroundPage.current.needsIndefiniteExecution = true
extension URL {
func asyncDownload(completion: @escaping (_ data: Data?, _ response: URLResponse?, _ error: Error?) -> ()) {
URLSession.shared
.dataTask(with: self, completionHandler: completion)
.resume()
}
}
let jsonURL = URL(string: "https://api.whitehouse.gov/v1/petitions.json?limit=100")!
let start = Date()
jsonURL.asyncDownload { data, response, error in
print("Download ended:", Date().description(with: .current))
print("Elapsed Time:", Date().timeIntervalSince(start), terminator: " seconds\n")
print("Data size:", data?.count ?? "nil", terminator: " bytes\n\n")
guard let data = data else {
print("URLSession dataTask error:", error ?? "nil")
return
}
do {
let jsonObject = try JSONSerialization.jsonObject(with: data)
if let dictionary = jsonObject as? [String: Any],
let results = dictionary["results"] as? [[String: Any]] {
DispatchQueue.main.async {
results.forEach { print($0["body"] ?? "", terminator: "\n\n") }
// self.tableData = results
// self.Indextableview.reloadData()
}
}
} catch {
print("JSONSerialization error:", error)
}
}
print("\nDownload started:", start.description(with: .current))