I could find some information how to read JSON for iOS. Nothing about macOS. When I try to apply the iOS code to macOS it gives me an error. For instance, this works in iOS but not macOS:

struct User: Codable {
    let name: String
    let email: String
}

class ViewController: NSViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        let url = URL(string: "https://jsonplaceholder.typicode.com/users")!

        URLSession.shared.dataTask(with: url) { data, _, _ in
            if let data = data {
                let users = try? JSONDecoder().decode([User].self, from: data)
                print (users![0].name)
            }
        }.resume()

    }

}

In the console I have a long error, at the end it says: NSLocalizedDescription=A server with the specified hostname could not be found. But this works in iOS and if you put the address in a browser it goes to a JSON file.

This isn't an issue with reading the JSON, it's an issue with connecting to the web.

You need to go into your project's capabilities and make sure that App Sandbox is on and Outgoing Connections are allowed.

You'll also need to go into your Info.plist and add App Transport Security Settings and, under that, Allow Arbitrary Loads in Web Content.

In info.plist I do not see Security Settings.

In any case, with the Outgoing Connections it seems the problem is solved

Thank you!