URLSEssion Does not send any response - ios

I was trying to learn the basics of networking with openweather api.
Implemented a very basic struct like this.
protocol WeatherManagerDelegate {
func didUpdateWeather(_ weatherManager : WeatherManager, weather : WeatherModel)
func didFailWithError(error: Error)
}
struct WeatherManager {
var delegate : WeatherManagerDelegate?
var temp : Double = 0.0
let weatherURL = "https://api.openweathermap.org/data/2.5/weather?appid=40ca58efce193db0fc801564afb08283&units=metric"
func fetchWheather(cityName : String){
let urlString = "\(weatherURL)&q=\(cityName)"
performRequest(with: urlString)
}
func performRequest(with urlString: String){
if let url = URL(string: urlString){
let session = URLSession(configuration: .default)
let task = session.dataTask(with: url){ (data, response, error) in
if error != nil{
delegate?.didFailWithError(error: error!)
return
}
if let safedata = data {
if let weather = self.parseJSON(weatherData: safedata){
// let WeatherVC = WeatherViewController()
self.delegate!.didUpdateWeather(self, weather: weather)
}
print("Data is \(safedata)")
}
}
task.resume()
}
}
func parseJSON(weatherData:Data)-> WeatherModel?{
let decoder = JSONDecoder()
do {
let decodedData = try decoder.decode(WeatherData.self, from: weatherData)
let id = decodedData.weather[0].id
let temp = decodedData.main.temp
let name = decodedData.name
let weather = WeatherModel(conditionID: id, cityName: name, temperature: temp)
return weather
} catch{
print("error is \(error)")
delegate?.didFailWithError(error: error)
return nil
}
}
}
But the issue is none of the print statements inside the requests are giving any outputs , nor i am able to update the UI. But the URL is giving the correct JSON Response when tried in browser
I am using the latest XCode on iOS 15 (iPhone 11 Device) with M1 Pro chip mac.
Found some threads which mentions to use "open with rosetta" but none of which worked.
also, not getting any errors on the console
Any solution?
Edit : Called in VC like this:
func textFieldDidEndEditing(_ textField: UITextField) {
if let city = searchTextField.text {
weatherManager.fetchWeather(cityName: city)
}
searchTextField.text = ""
}

Please try using:
let session = URLSession.shared
…instead of creating local session variable within the function scope
And if error != nil then don't return from that block. Simply use if-else for error handling.

Related

DispatchGroup Order of Operation

Hello i am trying to get result based on a result from another api.The getLatest function is going to get the latest object and will return the number then i want to generate a list of urls with the latest number and then sequentially get the data in the function getXKCDData.How can i achieve this.The dispatchgroup i have on there works sometimes but doesnt work all the time because generateUrlList is called before getting the latest number and it generate the wrong url.Which causes The operation couldn’t be completed. (XKCD_Comics.NetworkError error 1.) error.How can i achieve this.
final class NetworkManager {
public static var shared = NetworkManager()
private let sessions = URLSession.shared
private func generateUrlList(latestXKCD: Int) -> [String] {
print("Here at generateUrlList")
var urls = [String]()
for i in latestXKCD-100...latestXKCD{
let xkcd_url = "https://xkcd.com/\(i)/info.0.json"
urls.append(xkcd_url)
}
return urls
}
private func getLatest(completion: #escaping(Int) -> ()){
print("Here at get latest")
guard let url = URL(string: "https://xkcd.com/info.0.json") else { return }
let task = sessions.dataTask(with: url) { data, response, error in
guard let jsonData = data else { return }
do {
let decoder = JSONDecoder()
let response = try decoder.decode(Comics.self, from: jsonData)
completion(response.num)
}catch {
completion(0)
}
}
task.resume()
}
public func getXKCDData(completion: #escaping(Result<Comics,NetworkError>) -> Void){
let group = DispatchGroup()
var latestID = 0
group.enter()
self.getLatest { (result) in
latestID = result
group.leave()
}
let urlList = generateUrlList(latestXKCD: latestID)
print(urlList)
print("Here at getXKCDData")
for url in urlList {
group.enter()
guard let url = URL(string: url) else {
completion(.failure(.InvalidURL))
return
}
let task = sessions.dataTask(with: url) { data, response, error in
guard let jsonData = data else {
completion(.failure(.NoDataAvailable))
return
}
do {
let decoder = JSONDecoder()
let response = try decoder.decode(Comics.self, from: jsonData)
completion(.success(response))
group.leave()
}catch {
completion(.failure(.CanNotProcessData))
}
}
task.resume()
}
}
}

Nothing appearing the console when Decoding JSON in Swift

I'm trying to play around with a COVID dataset from Github (link in code below) but when I run the code nothing appears in the console. There are no errors appearing.
Can anyone advise on whats wrong here? Thanks in advance!
struct country: Decodable {
var location: String
var new_cases: Double
var people_fully_vaccinated: Double
}
func getJSON(){
guard let url = URL(string: "https://raw.githubusercontent.com/owid/covid-19-data/68c39808d445fe90b1fe3d57b93ad9be20f796d2/public/data/latest/owid-covid-latest.json") else{
return
}
let request = URLRequest(url: url)
URLSession.shared.dataTask(with: request){ (data, response, error) in
if let error = error{
print(error.localizedDescription)
return
}
guard let data = data else{
return
}
let decoder = JSONDecoder()
guard let decodedData = try? decoder.decode([country].self, from: data) else{
return
}
let countries = decodedData
for country in countries{
print (country.location)
}
}.resume()
}
getJSON()
You need
struct Root: Decodable {
var location: String
var new_cases: Double? // make it optional as it has some objects with nil
var people_fully_vaccinated: Double? // make it optional as it has some objects with nil
}
With
do {
let res = try decoder.decode([String:Root].self, from: data)
let locations = Array(res.values).map { $0.location }
print(locations)
}
catch {
print(error)
}

Send Barcode string to an API endpoint in Swift

I'm very new in programing, I have been learning swift5 for a few months now. I'm trying to make an APP that scan a 1D or 2D barcode, take the string and send it to an API endpoint which will give me back some info, for example, product number and batch number.
For the barcode part I'm using a really nice software from GitHub called BarcodeScanner. It is running without any issue and I'm able to get the string from the barcode it reads.
Once I have the string I'm able to send it to the API endpoint but then it gets stuck there.
If I run the same code in a playground it works without problems, it makes the request and I can see the answer in JSON from the server. If I run the code on the iPhone then it gets stuck. Of course I cannot use the scanning part when in playground, I use it to test the networking part and communication with the API.
Here is my Networking.swift file, it has some print() used for debug:
import Foundation
import UIKit
protocol NetworkManagerDelegate: class {
func didUpdatePharmo(pharmo: PharmoModel)
func didUpdateBarcode(barcode: BarcodeModel)
}
public struct NetworkManager {
var delegate: NetworkManagerDelegate?
let pharmoURL = "https://someurl.com/api"
let pharmoEndpoint = "https://someendpoint.com/api"
func fetchData(productNumber: String) {
let urlString = "\(pharmoURL)&number=\(productNumber)"
performRequestProductInfo(urlString: urlString)
print(urlString)
}
func fetchEndpoint(dataMatrix: String) {
let urlString = "\(pharmoEndpoint)&datamatrix=\(dataMatrix)"
performRequestEndpoint(urlString: urlString)
print(urlString)
}
func performRequestEndpoint(urlString: String) {
if let url = URL(string: urlString) {
let session = URLSession(configuration: .default)
var request = URLRequest(url: url)
request.httpMethod = "GET"
let task = session.dataTask(with: request) { (data, response, error) in
if error != nil {
print(error!)
return
}
if let response = response as? HTTPURLResponse {
print("EndPoint HTTP Status code: \(response.statusCode)")
}
if let safeData = data {
if let barcode = self.parseJSONEndpoint(endPointData: safeData) {
self.delegate?.didUpdateBarcode(barcode: barcode)
}
}
}
task.resume()
}
}
func parseJSONEndpoint(endPointData: Data) -> BarcodeModel? {
let decoder = JSONDecoder()
do {
let decodedData = try decoder.decode(BarcodeData.self, from: endPointData)
let productNumber = decodedData.product_number
let batchNumber = decodedData.batchnumber
let barcode = BarcodeModel(productNumber: productNumber, batchNumber: batchNumber)
print(batchNumber)
return barcode
} catch {
print(error)
return nil
}
}
func performRequestProductInfo(urlString: String) {
if let url = URL(string: urlString) {
let session = URLSession(configuration: .default)
var request = URLRequest(url: url)
request.httpMethod = "GET"
let task = session.dataTask(with: request) { (data, response, error) in
if error != nil {
print(error!)
return
}
if let response = response as? HTTPURLResponse {
print("ProductInfo HTTP Status code: \(response.statusCode)")
}
if let safeData = data {
if let pharmo = self.parseJSONProductInfo(pharmoData: safeData) {
self.delegate?.didUpdatePharmo(pharmo: pharmo)
}
}
}
task.resume()
}
}
func parseJSONProductInfo(pharmoData: Data) -> PharmoModel? {
let decoder = JSONDecoder()
do {
let decodedData = try decoder.decode(PharmoData.self, from: pharmoData)
let id = decodedData.id
let number = decodedData.number
let name = decodedData.name
let atcCode = decodedData.atc_code
let imagePath = decodedData.image_path
let displayImage = decodedData.display_image
let storageGroupId = decodedData.storage_group_id
let animalGroupId = decodedData.animal_group_id
let udlevbest = decodedData.udlevbest
let packageSizeText = decodedData.package_size_text
let packageSizeNum = decodedData.package_size_num
let unitCode = decodedData.unit_code
let strengthText = decodedData.strength_text
let prodPrice = decodedData.prod_price
let aupPrice = decodedData.aup_price
let aupInstPrice = decodedData.aup_inst_price
let animalGroups = decodedData.animal_groups
let udleveringsbestemmelse = decodedData.udleveringsbestemmelse
let animalGroup = decodedData.animal_group
let storageGroup = decodedData.storage_group
let species = decodedData.species
let indications = decodedData.indications
let substances = decodedData.substances
let manufacturer = decodedData.manufacturer
let pharmo = PharmoModel(id: id, number: number, name: name, atc_code: atcCode, image_path: imagePath, display_image: displayImage, storage_group_id: storageGroupId, animal_group_id: animalGroupId, udlevbest: udlevbest, package_size_text: packageSizeText, package_size_num: packageSizeNum, unit_code: unitCode, strength_text: strengthText, prod_price: prodPrice, aup_price: aupPrice, aup_inst_price: aupInstPrice, animal_groups: animalGroups, udleveringsbestemmelse: udleveringsbestemmelse, animal_group: animalGroup, storage_group: storageGroup, species: species, indications: indications, substances: substances, manufacturer: manufacturer)
print(name)
return pharmo
} catch {
print(error)
return nil
}
}
}
From the ViewController.swift running the barcode scanner I call the function fetchEndpoint(dataMatrix: String)
extension ViewController: BarcodeScannerCodeDelegate {
func scanner(_ controller: BarcodeScannerViewController, didCaptureCode code: String, type: String) {
print("Barcode Data: \(code)")
print("Symbology Type: \(type)")
DispatchQueue.main.asyncAfter(deadline: .now() + 3.0) {
networkManager.fetchEndpoint(dataMatrix: code)
}
}
}
From the console output I can see this 2 print() statements from ViewController.swift:
print("Barcode Data: \(code)")
print("Symbology Type: \(type)")
I can also see this print() statement from Networking.swift:
print(urlString)
But nothing happends after that. Again if I run the same code in a playground it works fine. I have also made requests using Postman, so I can see the JSON file and be sure the urlstring is working.
Anyone have some idea what am I doing wrong?
I was able to find the problem. The string being read from the scanner had an non ASCII character.
At any point XCode said anything about a non ASCII character, I had to copy the string into a playground, then I received this error:
Unprintable ASCII character found in source file
I copied the string into a terminal shell and I was able to see the character.
datamatrix=^]01036611030467831722113010RXT0711GC
I will try to use URLComponents or percent encoding

Pass data from a Parent ViewController to Child VC without Storyboards - Swift 5

I couldn't find a way to pass the data to the Child VC once i get the data through a UITextField from the Github API
protocol GithubManagerDelegate {
func didUpdateGithub(_ githubManager: GithubManager, github: GithubModel)
func didFailWithError(error: Error)
}
struct GithubManager {
let profileUrl = "https://api.github.com/users"
let clientId = // deleted this
let secretId = // deleted this
var delegate: GithubManagerDelegate?
func fetchProfile(profileName: String) {
let urlString = "\(profileUrl)/\(profileName)?client_id=\(clientId)&client_secret=\(secretId)"
performRequest(with: urlString)
}
func performRequest(with urlString: String) {
if let url = URL(string: urlString) {
let session = URLSession(configuration: .default)
let task = session.dataTask(with: url) { (data, response, error) in
if error != nil {
self.delegate?.didFailWithError(error: error!)
return
}
if let safeData = data {
if let github = self.parseJSON(safeData) {
self.delegate?.didUpdateGithub(self, github: github)
print(github)
}
}
}
task.resume()
}
}
func parseJSON(_ githubData: Data) -> GithubModel? {
let decoder = JSONDecoder()
do {
let decodeData = try decoder.decode(GithubData.self, from: githubData)
let name = decodeData.name ?? "The user does not have a name"
let login = decodeData.login ?? "No username by this name." // TODO: Change to give a alert
let avatarUrl = decodeData.avatar_url
let blog = decodeData.blog ?? "No Blog"
let bio = decodeData.bio ?? "No Bio"
let location = decodeData.location ?? "No location"
let followers = decodeData.followers
let following = decodeData.following
let github = GithubModel(githubName: login, githubUser: name, githubAvatar: avatarUrl, githubBio: bio, githubLocation: location, githubBlog: blog, githubFollowers: followers, githubFollowing: following)
return github
} catch {
delegate?.didFailWithError(error: error)
return nil
}
}
}
In the Parent VC in the textFieldDidEndEditing I take the input text and use that to fetch the information from the GithubAPI
if let username = searchTextField.text {
DispatchQueue.main.async {
self.githubManager.fetchProfile(profileName: username)
}
}
Then in my Child VC I use the GithubManagerDelegate, where I use DispatchQueue where, to populate the labels with the information. But the information is empty, because I can't pass the to the child once the data is recieved.
func didUpdateGithub(_ githubManager: GithubManager, github: GithubModel) {
DispatchQueue.main.async {
self.usernameLabel.text = github.githubName
}
}
The way I go from the ParentVC to ChildVC:
navigationController?.pushViewController(profileVC, animated: true)
Hopefully I made myself clear what the problem is...
when you try to pass data between parent ViewController and child ViewController you should add child not navigation to the child.
in child ViewController : var passingName: String?
For Example
let child = #YourChildViewController insitiate it.
self.addChild(child)
child.passingName = passingName
self.view.addSubview(child.view)
child.didMove(toParent: self)
I hope this solution helps you

Trying to append JSON items to array but not working

I am trying to serialize a GET request then make a movie object, then appending that movie object to a movies array which I will use to show info on the UI.
I am new and have struggled with this problem for some time now :(
If you look at the self.movies?.append(movie) shouldnt that work? I dont see any reasons as to when i try to get the first item i get fatal error index out of bounds which means I the Array is not filled yet.... Dont know what i am doing wrong :(
import UIKit
class ViewController: UIViewController {
var movies:[Movie]? = []
#IBOutlet weak var uiMovieTitle: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
getMovieData()
print(self.movies?.count)
setUI()
}
#IBAction func yesBtn(_ sender: UIButton) {
print(movies?[5].title ?? String())
}
#IBAction func seenBtn(_ sender: UIButton) {
}
#IBAction func noBtn(_ sender: UIButton) {
}
#IBOutlet weak var moviePoster: UIImageView!
let urlString = "https://api.themoviedb.org/3/discover/movie?api_key=935f539acbfed4b9e5534ddeed3fb57e&language=en-US&sort_by=popularity.desc&include_adult=false&include_video=false&page=1&with_genres=12"
func getMovieData(){
//Set up URL
let todoEndPoint: String = "https://api.themoviedb.org/3/discover/movie?api_key=935f539acbfed4b9e5534ddeed3fb57e&language=en-US&sort_by=popularity.desc&include_adult=false&include_video=false&page=1&with_genres=12"
guard let url = URL(string: todoEndPoint) else {
print("Cant get URL")
return
}
let urlRequest = URLRequest(url: url)
//Setting up session
let config = URLSessionConfiguration.default
let session = URLSession.shared
//Task setup
let task = session.dataTask(with: urlRequest) { (data, URLResponse, error) in
//Checking for errors
guard error == nil else{
print("Error calling GET")
print(error)
return
}
//Checking if we got data
guard let responseData = data else{
print("Error: No data")
return
}
self.movies = [Movie]()
do{//If we got data, if not print error
guard let todo = try JSONSerialization.jsonObject(with: responseData, options:.mutableContainers) as? [String:AnyObject] else{
print("Error trying to convert data to JSON")
return
}//if data is Serializable, do this
if let movieResults = todo["results"] as? [[String: AnyObject]]{
//For each movieobject inside of movieresult try to make a movie object
for moviesFromJson in movieResults{
let movie = Movie()
//If all this works, set variables
if let title = moviesFromJson["title"] as? String, let movieRelease = moviesFromJson["release_date"] as? String, let posterPath = moviesFromJson["poster_path"] as? String, let movieId = moviesFromJson["id"] as? Int{
movie.title = title
movie.movieRelease = movieRelease
movie.posterPath = posterPath
movie.movieId = movieId
}
self.movies?.append(movie)
}
}
}//do end
catch{
print(error)
}
}
////Do Stuff
task.resume()
}
func setUI(){
//uiMovieTitle.text = self.movies![0].title
//print(self.movies?[0].title)
}
}
my Movie class:
import UIKit
class Movie: NSObject {
var title:String?
var movieRelease: String?
var posterPath:String?
var movieId:Int?
var movieGenre:[Int] = []
//public init(title:String, movieRelease:String, posterPath:String,movieId:Int) {
// self.movieId = movieId
//self.title = title
//self.movieRelease = movieRelease
//self.posterPath = posterPath
//self.movieGenre = [movieGenre]
//}
}
getMovieData calls the network asynchronously. Your viewDidLoad invokes this, then calls setUI() - but the networking is still ongoing when setUI is called.
Instead, call setUI when the networking is complete - after the self.movies?.append(movie) line. The UI code will need to happen on the main thread. So...
for moviesFromJson... // your existing code
...
self.movies?.append(movie)
}
// Refresh UI now movies have loaded.
DispatchQueue.main.async {
setUI()
}
import UIKit
class ViewController: UIViewController {
var movies:[Movie]? = []
#IBOutlet weak var uiMovieTitle: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
getMovieDataCall(completionHandler: {data, error in self. getMovieDataCallBack(data: data, error: error)})
}
func getMovieDataCallBack(data: Data?, error: Error?) {
if error == nil {
let dictionary = try! JSONSerialization.jsonObject(with: data!, options: .allowFragments) as! Dictionary<String, AnyObject>
//do your appending here and then call setUI()
print("dictionaryMovie \(dictionary)")
} else {
showAlertView("", error?.localizedDescription)
}
}
func getMovieDataCall(completionHandler: #escaping (Data?, Error?) -> Void)){
//Set up URL
let todoEndPoint: String = "https://api.themoviedb.org/3/discover/movie?api_key=935f539acbfed4b9e5534ddeed3fb57e&language=en-US&sort_by=popularity.desc&include_adult=false&include_video=false&page=1&with_genres=12"
guard let url = URL(string: todoEndPoint) else {
print("Cant get URL")
return
}
let urlRequest = URLRequest(url: url)
//Setting up session
let config = URLSessionConfiguration.default
let session = URLSession.shared
//Task setup
let task = session.dataTask(with: urlRequest) { (data, URLResponse, error) in
if error != nil {
NSLog("GET-ERROR", "=\(error)");
completionHandler(nil, error)
} else {
let dataString = String(data: data!, encoding: String.Encoding(rawValue: String.Encoding.utf8.rawValue))
print(dataString!)
completionHandler(data, nil)
}
task.resume()
}
func setUI(){
}

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