Correctly Parsing JSON in Swift 3

Question

I\'m trying to fetch a JSON response and store the results in a variable. I\'ve had versions of this code work in previous releases of Swift, until the GM version of Xcode 8

Answer 1

Updated the isConnectToNetwork-Function afterwards, thanks to this post.

I wrote an extra method for it:

import SystemConfiguration

func loadingJSON(_ link:String, postString:String, completionHandler: @escaping (_ JSONObject: AnyObject) -> ()) {

    if(isConnectedToNetwork() == false){
        completionHandler("-1" as AnyObject)
        return
    }

    let request = NSMutableURLRequest(url: URL(string: link)!)
    request.httpMethod = "POST"
    request.httpBody = postString.data(using: String.Encoding.utf8)

    let task = URLSession.shared.dataTask(with: request as URLRequest) { data, response, error in
        guard error == nil && data != nil else { // check for fundamental networking error
            print("error=\(error)")
            return
        }

        if let httpStatus = response as? HTTPURLResponse , httpStatus.statusCode != 200 { // check for http errors
            print("statusCode should be 200, but is \(httpStatus.statusCode)")
            print("response = \(response)")
        }
        //JSON successfull
        do {
            let parseJSON = try JSONSerialization.jsonObject(with: data!, options: .allowFragments)
            DispatchQueue.main.async(execute: {
                completionHandler(parseJSON as AnyObject)
            });
        } catch let error as NSError {
            print("Failed to load: \(error.localizedDescription)")
        }
    }
    task.resume()
}

func isConnectedToNetwork() -> Bool {

    var zeroAddress = sockaddr_in(sin_len: 0, sin_family: 0, sin_port: 0, sin_addr: in_addr(s_addr: 0), sin_zero: (0, 0, 0, 0, 0, 0, 0, 0))
    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 = SCNetworkReachabilityFlags(rawValue: 0)
    if SCNetworkReachabilityGetFlags(defaultRouteReachability!, &flags) == false {
        return false
    }

    let isReachable = (flags.rawValue & UInt32(kSCNetworkFlagsReachable)) != 0
    let needsConnection = (flags.rawValue & UInt32(kSCNetworkFlagsConnectionRequired)) != 0
    let ret = (isReachable && !needsConnection)

    return ret
}

So now you can easily call this in your app wherever you want

loadingJSON("yourDomain.com/login.php", postString:"email=\(userEmail!)&password=\(password!)") { parseJSON in

    if(String(describing: parseJSON) == "-1"){
        print("No Internet")
    } else {

    if let loginSuccessfull = parseJSON["loginSuccessfull"] as? Bool {
        //... do stuff
    }
}