How to await an asynchronous function in Swift? [duplicate] - ios

Question

This question already has answers here:
Returning data from async call in Swift function
(13 answers)
Closed 2 years ago.
I'm coming from a JavaScript/Flutter environment and I need to await an asynchronous function in Swift. Is there a way to do it?
Basically, I want to return repoNames from a class but a "task" is executing way faster than a return keyword.
Here's the code:
import UIKit
class SearchViewModel {
let textFieldText: String?
var repoNames: Array<String> = []
init(textFieldText: String?) {
self.textFieldText = textFieldText
}
func searchForRepo() -> Array<String> {
let baseUrl = "https://api.github.com/search/repositories?q="
let finalUrl = URL(string: baseUrl + self.textFieldText!)
let session = URLSession.shared
let task = session.dataTask(with: finalUrl!) { (data, response, error) in
guard let data = data else { return }
let repos: Items = try! JSONDecoder().decode(Items.self, from: data)
for repo in repos.items {
self.repoNames.append(repo.name)
print(self.repoNames)
}
}
task.resume()
return self.repoNames
}
}

Answer 1

Add a completion
func searchForRepo(completion:#escaping( [String] -> ())) -> {
let baseUrl = "https://api.github.com/search/repositories?q="
let finalUrl = URL(string: baseUrl + self.textFieldText!)
URLSession.shared.dataTask(with: finalUrl!) { (data, response, error) in
guard let data = data else { return }
do {
let repos = try JSONDecoder().decode(Items.self, from: data)
self.repoNames = repos.items.map { $0repo.name }
completion(self.repoNames)
}
catch {
print(error)
}
}.resume()
}
When calling
SearchViewModel(textFieldText:"someValue").searchForRepo { res in
print(res)
}