How to show an Alert message when there is no internet connection, swift code

Use this code to show an alert to the user when there is no internet connection. SWIFT IOS code

import SystemConfiguration

override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        if isInternetAvailable() {
            observeUsers()
        } else {
            let alert = UIAlertController(title: "No Connection", message: "No internet connection, connect to the internet and try again.", preferredStyle: .alert)
            alert.addAction(UIAlertAction(title: "ok", style: .default, handler: nil))
            present(alert, animated: true, completion: nil)
            
            return
        }
        
    }



  func isInternetAvailable() -> Bool {
        var zeroAddress = sockaddr_in()
        zeroAddress.sin_len = UInt8(MemoryLayout.size(ofValue: zeroAddress))
        zeroAddress.sin_family = sa_family_t(AF_INET)
        
        let defaultRouteReachability = withUnsafePointer(to: &zeroAddress) {
            $0.withMemoryRebound(to: sockaddr.self, capacity: 1) {zeroSockAddress in
                SCNetworkReachabilityCreateWithAddress(nil, zeroSockAddress)
            }
        }
        
        var flags = SCNetworkReachabilityFlags()
        if !SCNetworkReachabilityGetFlags(defaultRouteReachability!, &flags) {
            return false
        }
        let isReachable = flags.contains(.reachable)
        let needsConnection = flags.contains(.connectionRequired)
        return (isReachable && !needsConnection)
    }