This is my request funtion:
func receiptValidation(completion: #escaping(_ isPurchaseSchemeActive: Bool, _ error: Error?) -> ()) {
let receiptFileURL = Bundle.main.appStoreReceiptURL
guard let receiptData = try? Data(contentsOf: receiptFileURL!) else {
//This is the First launch app VC pointer call
completion(false, nil)
return
}
let recieptString = receiptData.base64EncodedString(options: NSData.Base64EncodingOptions(rawValue: 0))
let jsonDict: [String: AnyObject] = ["receipt-data" : recieptString as AnyObject, "password" : "7bb160f1c8ec4d929fbc751c507d24fd" as AnyObject]
do {
let requestData = try JSONSerialization.data(withJSONObject: jsonDict, options: JSONSerialization.WritingOptions.prettyPrinted)
let storeURL = URL(string: self.verifyReceiptURL)!
var storeRequest = URLRequest(url: storeURL)
storeRequest.httpMethod = "POST"
storeRequest.httpBody = requestData
let session = URLSession(configuration: URLSessionConfiguration.default)
let task = session.dataTask(with: storeRequest, completionHandler: { [weak self] (data, response, error) in
do {
if let jsonResponse = try JSONSerialization.jsonObject(with: data!, options: JSONSerialization.ReadingOptions.mutableContainers) as? NSDictionary {
print("json response \(jsonResponse)")
if let expiresDate = self?.getPurchaseAndExpirationDateFromResponse(jsonResponse, keyString: "expires_date") {
//print("expiresDate \(expiresDate)")
let purchaseStatus = self?.isSubscriptionActive(expireDate: expiresDate)
if let purchaseStatus = purchaseStatus {
completion(purchaseStatus, nil)
}
}
}
} catch let parseError {
completion(false, parseError)
}
})
task.resume()
} catch let parseError {
completion(false, parseError)
}
}
This is how I am calling it:
func callForVal() {
receiptValidation() { isPurchaseSchemeActive, error in
if let err = error {
self.onBuyProductHandler?(.failure(err))
} else {
self.onBuyProductHandler?(.success(isPurchaseSchemeActive))
}
}
}
But sometimes It takes a long time to give a response back. Now I want to call it with a 60 seconds timer If do not get any response within these 60 seconds. How can I do it?
Related
I make some code using swift 4 to load image from URL, but every time I add images to server, it took a lot of time to load it in colection view or table view. I want to try store it in NScache but i dont understand to do it. can anyone help me, I'm new in swift :(
#objc func loadPosts() {
let url = URL(string: "http://someURL/Url.php")!
var request = URLRequest(url: url)
request.httpMethod = "POST"
let body = "phomepost=\(homepost)"
request.httpBody = body.data(using: String.Encoding.utf8)
URLSession.shared.dataTask(with: request) { data, response, error in
DispatchQueue.main.async(execute: {
if error == nil {
do{
let json = try JSONSerialization.jsonObject(with: data!, options: .mutableContainers) as? NSDictionary
self.comments.removeAll(keepingCapacity: false)
self.images.removeAll(keepingCapacity: false)
self.collectionView?.reloadData()
guard let parseJSON = json else {
print("Error While Parsing")
return
}
guard let posts = parseJSON["posts"] as? [AnyObject] else {
print("Error while parseJSONing")
return
}
self.comments = posts.reversed()
for i in 0 ..< self.comments.count {
let path = self.comments[i]["path"] as? String
if !path!.isEmpty {
let url = NSURL(string: path!)!
let imageData = try? Data(contentsOf: url as URL)
let image = UIImage(data: imageData! as Data)!
self.images.append(image)
} else {
let image = UIImage()
self.images.append(image)
}
}
self.collectionView?.reloadData()
//print(posts.count)
} catch {
print(error)
}
}else{
print(error)
}
})
}.resume()
}
You can use something like this:
private let cache = NSCache<NSString, NSData>()
.....
func downloadImage(url: String, handler: #escaping(Data?, Error?) -> Void){
let cacheID = NSString(string: url)
if let cachedData = cache.object(forKey: cacheID) {
handler((cachedData as Data), nil)
}else{
if let url = URL(string: url) {
let session = URLSession(configuration: urlSessionConfig)
var request = URLRequest(url: url)
request.cachePolicy = .returnCacheDataElseLoad
request.httpMethod = "get"
session.dataTask(with: request) { (data, response, error) in
if let _data = data {
self.cache.setObject(_data as NSData, forKey: cacheID)
handler(_data, nil)
}else{
handler(nil, error)
}
}.resume()
} else {
// NetworkError is a custom error
handler(nil, NetworkError.invalidURL)
}
}
}
}
This will add a small animation while loading using image set.
let imageCache = NSCache<AnyObject, AnyObject>()
extension UIImageView {
func loadImageFromUrl(urlString: String) {
let loader1 = UIImage(named: "loaderImage1.png")
let loader2 = UIImage(named: "loaderImage2.png")
let loader3 = UIImage(named: "loaderImage3.png")
let imageArray = [loader1, loader2, loader3]
let animatedImage = UIImage.animatedImage(with: imageArray as! [UIImage], duration: 1.7)
if let imageFromCache = imageCache.object(forKey: urlString as AnyObject) as? UIImage{
self.image = imageFromCache
return
} else {
self.image = animatedImage
Alamofire.request(urlString, method: .get).response { (responseData) in
if let data = responseData.data {
DispatchQueue.main.async {
if let imageToCache = UIImage(data: data){
imageCache.setObject(imageToCache, forKey: urlString as AnyObject)
self.image = imageToCache
}
}
}
} //alamofire
}
}
}
I am trying to build a user regeistration form, which should check if the user already exists. So I am sending a php request to my my mysql server. If the return value is empty, the user does not exists yet.
Unfortunatley I am really stuck with waiting for this check to finish. I tried several solutions I found googleing but none of them worked. My current code uses semaphores and will crash with "fatal error: unexpectedly found nil while unwrapping an Optional value", so the semaphore is not waiting until the task is finished as I would expect it.
Any hints, would be greatly appreciated. Thanks guys.
private func isUniqueEmail(email: String) -> Bool {
var result: Bool?
let semaphore = DispatchSemaphore(value: 1)
let requestURL = URL(string: "http://localhost/firstpostget/functions/get.php")
var request = URLRequest(url: requestURL!)
request.httpMethod = "POST"
let postParameters = "email=" + email
request.httpBody = postParameters.data(using: .utf8)
let configuration = URLSessionConfiguration.default
let session = URLSession(configuration: configuration, delegate: nil, delegateQueue: OperationQueue.main)
let task = session.dataTask(with: request) {(data, response, error) in
var myJson: AnyObject
do{
myJson = try JSONSerialization.jsonObject(with: data!, options: JSONSerialization.ReadingOptions.mutableContainers) as AnyObject
if myJson.count == 0{
result = true
semaphore.signal()
} else{
result = false
semaphore.signal()
}
} catch{
//TODO
print(error)
}
}
task.resume()
semaphore.wait(timeout: .distantFuture)
return result!
}
Your task is async and you are force unwrapping nil value so this is the reason it crashes.
You have to change your function implementation to also be async, for example using closures:
private func isUniqueEmail(email: String, completion: ((Bool) -> (Void))?) {
let requestURL = URL(string: "http://localhost/firstpostget/functions/get.php")
var request = URLRequest(url: requestURL!)
request.httpMethod = "POST"
let postParameters = "email=" + email
request.httpBody = postParameters.data(using: .utf8)
let configuration = URLSessionConfiguration.default
let session = URLSession(configuration: configuration, delegate: nil, delegateQueue: OperationQueue.main)
let task = session.dataTask(with: request) {(data, response, error) in
var myJson: AnyObject
do{
myJson = try JSONSerialization.jsonObject(with: data!, options: JSONSerialization.ReadingOptions.mutableContainers) as AnyObject
if myJson.count == 0 {
completion?(true)
} else{
completion?(false)
}
} catch{
//TODO
print(error)
}
}
task.resume()
}
Now you can use this function in this way:
isUniqueEmail(email: "aaa#bbbb.com") { result in
if result {
print("email unique")
} else {
print("email not unique")
}
}
I think you should rethink the pattern you're using to get the data out of your request, you should consider using a custom handler/callback method that you pass along with the email you're trying to check. See below for an example:
private func isUniqueEmail(email: String, handler: ((_ result: Bool) -> Void)?) -> Void {
let requestURL = URL(string: "http://localhost/firstpostget/functions/get.php")
var request = URLRequest(url: requestURL!)
request.httpMethod = "POST"
let postParameters = "email=" + email
request.httpBody = postParameters.data(using: .utf8)
let configuration = URLSessionConfiguration.default
let session = URLSession(configuration: configuration, delegate: nil, delegateQueue: OperationQueue.main)
let task = session.dataTask(with: request) {(data, response, error) in
var myJson: AnyObject
var result: Bool = false
do{
myJson = try JSONSerialization.jsonObject(with: data!, options: JSONSerialization.ReadingOptions.mutableContainers) as AnyObject
if myJson.count == 0 {
result = true
}
guard handler != nil else {
return
}
handler!(result)
} catch{
//TODO
print(error)
}
}
task.resume()
}
Run:
isUniqueEmail(email: "test#test.com", handler: { result in
print(result) // true || false
})
If you really want to go down the "wait" route then take a took at DispatchGroup's
https://developer.apple.com/documentation/dispatch/dispatchgroup
try using this:
ApihelperClass
static let sharedInstance = ApihelperClass()
typealias CompletionHandler = (_ success:Bool, _ error:Bool, _ result:NSDictionary) -> Void
typealias ErrorHandler = (_ success: Bool, _ error:Bool) -> Void
func callPostRequest(_ urlPath: String, params:[String: AnyObject], completionHandler: #escaping CompletionHandler, errorHandler:#escaping ErrorHandler ){
print("urlPath:==> \(urlPath) ")
let session = Foundation.URLSession.shared
let url = URL(string: urlPath)
var request = URLRequest(url : url!)
request.httpMethod = "POST"
do {
let jsonData = try JSONSerialization.data(withJSONObject: params, options: .prettyPrinted)
request.setValue("application/json; charset=utf-8", forHTTPHeaderField: "Content-Type")
request.httpBody = jsonData
session.dataTask(with: request, completionHandler: { data, response, error in
OperationQueue.main.addOperation {
guard error == nil && data != nil else { // check for fundamental networking error
print("error=\(error)")
errorHandler(false, true)
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)")
}
let responseString = String(data: data!, encoding: String.Encoding.utf8)
print("responseString = \(responseString!)")
if let responsedata = responseString!.data(using: String.Encoding.utf8)! as? Data{
do {
let jsonResult:NSDictionary = try JSONSerialization.jsonObject(with: responsedata, options: []) as! NSDictionary
print("Get The Result \(jsonResult)")
//parse your jsonResult as per your requirements
if error != nil {
print("error=\(error)")
completionHandler(false, true, jsonResult)//
}
if let str = jsonResult["success"] as? NSNull {
print("error=\(str)")
completionHandler(false, true, jsonResult)
}
else {
let responseString = NSString(data: data!, encoding: String.Encoding.utf8.rawValue)
// print("Response string : \(responseString)")
completionHandler(true, false, jsonResult)
}
} catch let error as NSError {
print(error.localizedDescription)
}
}
}
}) .resume()
}catch {
print("Error ->Catch")
}
}
Add to your viewcontroller
func isUniqueEmail(email: String){
ApihelperClass.sharedInstance.callPostRequest("http://localhost/firstpostget/functions/get.php", params: ["email":email as AnyObject], completionHandler: { (success, error, result) in
//success 200
}) { (success, error) in
//error
}
}
you can use URlSession like :
func isUniqueEmail(email: String,completion: #escaping (Bool) -> ()) {
var request = URLRequest(url: URL(string: "http://localhost/firstpostget/functions/get.php")!)
request.httpMethod = "POST"
let postString = "email=\(email)"
request.httpBody = postString.data(using: .utf8)
// loading to wait request
UIApplication.shared.isNetworkActivityIndicatorVisible = true
let task = URLSession.shared.dataTask(with: request) { data, response, error in
// we get request request
UIApplication.shared.isNetworkActivityIndicatorVisible = false
guard let data = data, error == nil else { // check for fundamental networking error
print("error=\(String(describing: error))")
completion(false)
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 = \(String(describing: response))")
completion(false)
}else{
completion(true)
}
let responseString = String(data: data, encoding: .utf8)
print("responseString = \(String(describing: responseString))")
}
task.resume()
}
and used in code Like
self.isUniqueEmail(email: "your Email") { (isExit) in
if isExit {
}else{
}
}
Ok, I just found a solution. My semaphore approach actually worked as well as dispatchgroups. The task just needed to be URLSession.shared.dataTask
Still thank's a lot for all the answers.
I am trying to create a callback on swift 3 but haven't had any luck so far. I was taking a look at this question: link which is similar, but the answer gives me an error.
Basically I have an API struct with a static function that I need to have a callback.
import UIKit
struct API {
public static func functionWithCallback(params: Dictionary<String, String>, success: #escaping ((_ response: String) -> Ticket), failure: #escaping((_ error:String) -> String) ) {
let app_server_url = "http://api.com" + params["key"]!
let url: URL = URL(string: app_server_url)!
var request: URLRequest = URLRequest(url: url)
request.httpMethod = "POST"
do {
request.httpBody = try JSONSerialization.data(withJSONObject: params, options: .prettyPrinted)
} catch let error {
print(error.localizedDescription)
}
request.addValue("application/json charset=utf-8", forHTTPHeaderField: "Content-Type")
request.addValue("application/json charset=utf-8", forHTTPHeaderField: "Accept")
let session = URLSession.shared
let task = session.dataTask(with: request as URLRequest, completionHandler: { data, response, error in
guard error == nil else {
return
}
guard let data = data else {
return
}
DispatchQueue.main.async {
do {
let json = try JSONSerialization.jsonObject(with: data) as! [String: Any]
print(json)
var message = ""
if let result = json["result"] as? String {
if(result == "success") {
//attempt to call callback gives me an error: extra argument in call
success("") {
let ticket = json["ticket"] as! NSDictionary
var date = ticket["date"] as! String
var ticket: Ticket = nil
ticket.setDate(date: date)
return ticket
}
}
else {
message = json["message"] as! String
print(message)
}
} catch let error {
print(error.localizedDescription)
let description = error.localizedDescription
if let data = description.data(using: .utf8) {
do {
let jsonError = try JSONSerialization.jsonObject(with: data, options: []) as? [String: Any]
let message = jsonError?["message"] as! String
} catch {
}
}
}
}
})
task.resume()
}
}
So I basically can't call the callback success because it gives me an error: Extra argument in call. Any idea on how to fix it?
My goal is to call:
API.functionWithCallback(params: params, success() -> Ticket {
//do something with the returned ticket here
},
error() -> () {
//do something with the error message here
}
)
I believe you have it wrong on how to use call back closures, from what I can understand of your question you want to do something with the ticket in the call back closure and to do that it should be a parameter of the closure not the return type of the closure.
Replace your function declaration with this:
public static func functionWithCallback(params: Dictionary<String, String>, success: #escaping ((_ response: String, _ ticket: Ticket) -> Void), failure: #escaping((_ error:String) -> Void) ) {
And inside the function replace this:
success("") {
let ticket = json["ticket"] as! NSDictionary
var date = ticket["date"] as! String
var ticket: Ticket = nil // Im not sure what you are trying to do with this line but this will definitely give an error
ticket.setDate(date: date)
return ticket
}
With:
let ticket = json["ticket"] as! NSDictionary
var date = ticket["date"] as! String
var ticket: Ticket = nil // fix this line
ticket.setDate(date: date)
success("",ticket)
And then you can call the function like this:
API.functionWithCallback(params: params, success: { response, ticket in
// you can use ticket here
// and also the response text
}) { errorMessage in
// use the error message here
}
Try this :
func uploadImage(api: String,token : String, methodType : String, requestDictionary: [String:AnyObject],picData:[Data], successHandler: #escaping (AnyObject) -> Void,failureHandler: #escaping (NSError) -> Void)
{
if Common_Methods.Reachability1.isConnectedToNetwork() == false
{
let del :AppDelegate = (UIApplication.shared.delegate as? AppDelegate)!
let nav : UINavigationController = (del.window?.rootViewController as? UINavigationController)!
let alert = UIAlertController(title: "", message: "The Internet connection appears to be offline" , preferredStyle: UIAlertControllerStyle.alert)
// Create the actions
let okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.default)
{
UIAlertAction in
}
alert.addAction(okAction)
nav.present( alert, animated: true, completion: nil)
return
}
let apiUrl = "\(KbaseUrl)\(api)"
let session = URLSession.shared
let url: NSURL = NSURL(string: apiUrl as String)!
print(url)
let request = NSMutableURLRequest(url: url as URL)
request.httpMethod = methodType
let boundary = NSString(format: "---------------------------14737809831466499882746641449") as String
//-------- add token as perameter and set a check if token not nill then set token in header -------
if(token.characters.count > 0)
{
request.setValue(token, forHTTPHeaderField: "x-logintoken")
}
request.setValue("Keep-Alive", forHTTPHeaderField: "Connection")
request.setValue("multipart/form-data; boundary="+boundary, forHTTPHeaderField: "Content-Type")
let data = createBodyWithParameters(parameters: requestDictionary, filePathKey:nil, imageDataKey: picData.count > 0 ? picData : [], boundary: boundary)
print(data)
request.httpBody = data
let task = session.dataTask(with: request as URLRequest) { data, response, error in
// handle fundamental network errors (e.g. no connectivity)
guard error == nil && data != nil else {
successHandler(data as AnyObject )//completion(data as AnyObject?, error as NSError?)
print(error)
DispatchQueue.main.async {
Common_Methods.hideHUD(view: (topVC?.view)!)
}
return
}
// check that http status code was 200
if let httpResponse = response as? HTTPURLResponse , httpResponse.statusCode != 200 {
do {
let responseObject = try JSONSerialization.jsonObject(with: data!, options: []) as? NSDictionary
if let responseDictionary = responseObject as? [String:AnyObject]
{
if responseDictionary["statusCode"] as! Int == 401
{
// self.objDelegate.sessionExpire(msgStr: "Session Expired. Please login again to continue.")
}
else
{
//completion(String(data: data!, encoding: String.Encoding.utf8) as AnyObject?, nil)
}
}
} catch let error as NSError {
print(error)
DispatchQueue.main.async {
Common_Methods.hideHUD(view: (topVC?.view)!)
}
// completion(String(data: data!, encoding: String.Encoding.utf8) as AnyObject?, nil)
}
}
// parse the JSON response
do {
DispatchQueue.main.async {
Common_Methods.hideHUD(view: (topVC?.view)!)
}
let responseObject = try JSONSerialization.jsonObject(with: data!, options: []) as? NSDictionary
successHandler(responseObject! )
} catch let error as NSError {
DispatchQueue.main.async {
Common_Methods.hideHUD(view: (topVC?.view)!)
}
// completion(String(data: data!, encoding: String.Encoding.utf8) as AnyObject?, error)
failureHandler(error)
}
}
task.resume()
// return task
}
and function Call is :
WebService.sharedInstance.uploadImage(api: KEditEmployerProfile,token: token,methodType: "PUT", requestDictionary: parameters1 as! [String : AnyObject], picData: [imageData as Data], successHandler: { (responseObject) in
print(responseObject)
}) { (error) in
print(error)
}
}
I want to cast jsonResult to NSDicitonary to be able to do a callback of jsonResult. Is this possible?
func request(url:String,callback:(NSDictionary)->()) {
let nsURL = NSURL(string: url)
let session = NSURLSession.sharedSession()
let task = session.dataTaskWithURL(nsURL!, completionHandler: { (data, response, error) -> Void in
if error != nil {
print(error)
} else {
do {
let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.MutableContainers) as! NSArray
print(jsonResult[0])
} catch {
print("my error")
}
}
})
If I understand your question, you can use optional binding to cast your object:
if let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options: []) as? NSArray {
if let dict = jsonResult[0] as? NSDictionary {
callback(dict)
}
}
I'm a C# developer convert to Swift tvOs and just starting to learn. I've made some progress, but not sure how to handle nested calls to json. The sources are from different providers so I can't just combine the query.
How do I wait for the inner request to complete so the TVSeries has the poster_path? Is there a better way to add the show to the collection and then process the poster path loading in another thread so it doesn't delay the UI Experience?
func downloadTVData() {
let url_BTV = NSURL(string: BTV_URL_BASE)!
let request_BTV = NSURLRequest(URL: url_BTV)
let session_BTV = NSURLSession.sharedSession()
//get series data
let task_BTR = session_BTV.dataTaskWithRequest(request_BTV) { (data_BTV, response_BTV, error_BTV) -> Void in
if error_BTV != nil {
print (error_BTV?.description)
} else {
do {
let dict_BTV = try NSJSONSerialization.JSONObjectWithData(data_BTV!, options: .AllowFragments) as? Dictionary<String, AnyObject>
if let results_BTV = dict_BTV!["results"] as? [Dictionary<String, AnyObject>]{
for obj_BTV in results_BTV {
let tvshow = TVSeries(tvDict: obj_BTV)
//for each tv series try to load a poster_path from secondary provider
if let str = obj_BTV["title"] as? String!{
let escapedString = str?.stringByAddingPercentEncodingWithAllowedCharacters(.URLQueryAllowedCharacterSet())!
if let url = NSURL(string: self.SEARCH_URL_BASE + escapedString!) {
let request = NSURLRequest(URL: url)
let session = NSURLSession.sharedSession()
let task = session.dataTaskWithRequest(request) { (data, response, error) -> Void in
if error != nil {
print (error?.description)
} else {
do {
let dict = try NSJSONSerialization.JSONObjectWithData(data!, options: .AllowFragments) as? Dictionary<String, AnyObject>
if let results = dict!["results"] as? [Dictionary<String, AnyObject>] {
//iterate through the poster array
for obj in results {
if let path = obj["poster_path"] as? String {
tvshow.posterPath = path
break
}
}
}
} catch let error as NSError {
print(error.description)
}
}
}
task.resume()
}
}
self.tvSeries.append(tvshow)
}
dispatch_async(dispatch_get_main_queue()){
self.collectionView.reloadData()
}
}
} catch let error as NSError {
print(error.description)
}
}
}
task_BTR.resume()
}
Thanks for your help!
I would recommend breaking things apart into multiple methods, with callbacks to sequence the operations, and utilizing Swift's built-in throws error handling mechanism. Here's an example, not perfect, but might help as a starting point:
class TVSeries
{
let title: String
var posterPath: String?
enum Error: ErrorType {
case MalformedJSON
}
init(tvDict: [String: AnyObject]) throws
{
guard let title = tvDict["title"] as? String else {
throw Error.MalformedJSON
}
self.title = title
}
static func loadAllSeries(completionHandler: [TVSeries]? -> Void)
{
NSURLSession.sharedSession().dataTaskWithURL(NSURL(string: BTV_URL_BASE)!) { data, response, error in
guard let data = data else {
print(error)
completionHandler(nil)
return
}
do {
completionHandler(try fromJSONData(data))
}
catch let error {
print(error)
}
}.resume()
}
static func fromJSONData(jsonData: NSData) throws -> [TVSeries]
{
guard let dict = try NSJSONSerialization.JSONObjectWithData(jsonData, options: .AllowFragments) as? [String: AnyObject] else {
throw Error.MalformedJSON
}
guard let results = dict["results"] as? [[String: AnyObject]] else {
throw Error.MalformedJSON
}
return try results.map {
return try TVSeries(tvDict: $0)
}
}
func loadPosterPath(completionHandler: () -> Void)
{
guard let searchPath = title.stringByAddingPercentEncodingWithAllowedCharacters(.URLQueryAllowedCharacterSet()) else {
completionHandler()
return
}
let url = NSURL(string: SEARCH_URL_BASE)!.URLByAppendingPathComponent(searchPath)
NSURLSession.sharedSession().dataTaskWithURL(url) { [weak self] data, response, error in
defer { completionHandler() }
guard let strongSelf = self else { return }
guard let data = data else {
print(error)
return
}
do {
strongSelf.posterPath = try TVSeries.posterPathFromJSONData(data)
}
catch let error {
print(error)
}
}.resume()
}
static func posterPathFromJSONData(jsonData: NSData) throws -> String?
{
guard let dict = try NSJSONSerialization.JSONObjectWithData(jsonData, options: .AllowFragments) as? [String: AnyObject] else {
throw Error.MalformedJSON
}
guard let results = dict["results"] as? [[String: AnyObject]] else {
throw Error.MalformedJSON
}
for result in results {
if let path = result["poster_path"] as? String {
return path
}
}
return nil
}
}
It might also be worth your time to look into something like RxSwift or Alamofire, which help you with these kinds of data-conversion / sequencing operations.