I'm trying to make this method accessible throughout the app because there are many view controllers need JSON response depending on the path and the language parameters, but I'm not sure what pattern to use or how to structure the app.
func fetchJsonFor(path: String, langugae: String) -> AnyObject{
var components = URLComponents()
components.scheme = Constants.APIScheme
components.host = Constants.APIHost
components.path = Constants.APIPath
components.path.append(path)
components.path.append(langugae)
let request = URLRequest(url: components.url!)
var parsedJSON: AnyObject!
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
if error != nil{
print(error?.localizedDescription ?? "Error")
return
}
guard let data = data else{
return
}
do{
parsedJSON = try JSONSerialization.jsonObject(with: data, options: .allowFragments) as AnyObject
} catch{
print("Can't parse JSON: \(data)")
return
}
}
task.resume()
return parsedJSON
}
You can go for Single Tone Design pattern.
Also remember you can't return the URLRequest response as functions return. It is a asynchronous task which not works in main thread. So return will not work.
You need to make use of closure ----> a completion block will more suitable.
class WebService {
static let shared = WebService()
func fetchJsonFor(path: String, langugae: String,completion:((Any?) -> Void)){
var components = URLComponents()
components.scheme = Constants.APIScheme
components.host = Constants.APIHost
components.path = Constants.APIPath
components.path.append(path)
components.path.append(langugae)
let request = URLRequest(url: components.url!)
var parsedJSON: AnyObject!
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
if error != nil{
print(error?.localizedDescription ?? "Error")
completion(nil)
}
guard let data = data else{
completion(nil)
}
do{
parsedJSON = try JSONSerialization.jsonObject(with: data, options: .allowFragments)
completion(parsedJSON)
} catch{
print("Can't parse JSON: \(data)")
completion(nil)
}
}
task.resume()
}
}
How to use..
From your ViewController Class you can call web service like
WebService.shared.fetchJsonFor(path: "YOUR_PATH", langugae: "YOUR_LANGUAGE") { (response) in
if let response = response{
// Success response
}else{
//Failed response
}
}
Related
I'm trying to retrieve some data from an API, but I got an error: "The given data was not valid JSON ", Status code: 401
I think that is an authentication problem. How can I set the auth credentials to make the GET request?
This is the code for retrieving the data from the JSON.
func loadData()
{
guard let url = URL(string: getUrl) else { return }
URLSession.shared.dataTask(with: url) { data, res, err in
do {
if let data = data {
let result = try JSONDecoder().decode([ItemsModel].self, from: data)
DispatchQueue.main.async {
self.items = result
}
} else {
print(" No Data ")
}
} catch( let error)
{
print(res)
print(String(describing: error))
}
}.resume()
}
This is the code for the view :
struct GetView: View {
#ObservedObject var viewModel = ViewModel()
var body: some View {
NavigationView {
VStack {
List(viewModel.items, id: \.id) { item in
Text(item.year)
}
} .onAppear(perform: {
viewModel.loadData()
})
.navigationTitle("Data")
}
}
}
To handle authentication you must implement a delegate for your URLSession:
func urlSession(_ session: URLSession, didReceive challenge: URLAuthenticationChallenge, completionHandler: #escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
completionHandler(.performDefaultHandling, challenge.proposedCredential)
}
However, your 401 error may be due to your code not sending a valid GET request to the server. You probably want to decode the 'res' value to determine the status code:
if let response = res as? HTTPURLResponse {
if response.statusCode != 200 {
// data may be JSON encoded but you should get some for
// statusCode == 401
}
}
Without knowing the kind of service you are connecting to it is hard to speculate if you need a GET or a POST. The URL you use may require a query parameter.
I found the solution. This is the code for Basic Auth :
func loadData() {
//Credentials
let username = ""
let password = ""
let loginString = "\(username):\(password)"
let loginData = loginString.data(using: String.Encoding.utf8)!
let base64LoginString = loginData.base64EncodedString()
//Request
guard let url = URL(string: getUrl) else {return}
var request = URLRequest(url: url)
request.httpMethod = "GET"
request.setValue("Basic \(base64LoginString)", forHTTPHeaderField: "Authorization")
//Setup Session
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
do {
if let data = data {
print(String(data: data, encoding: .utf8)!)
let result = try JSONDecoder().decode([ItemsModel].self, from: data)
DispatchQueue.main.async {
self.items = result
}
}
else {
print(" No Data ")
}
} catch( let error)
{
print(String(describing: error))
}
}
task.resume()
}
The JSON data is
[
{"id":0,"temperature":77,"humidity":0.22,"timeCaptured":"2020-09-25T19:33:27.9733333"},
{"id":0,"temperature":77,"humidity":0.22,"timeCaptured":"2020-09-25T20:38:53.3"},
{"id":0,"temperature":85,"humidity":0.25,"timeCaptured":"2020-09-25T20:38:53.3"},
{"id":0,"temperature":88,"humidity":0.22,"timeCaptured":"2020-09-28T15:30:00"},
// ...
]
My structs look like this
struct TemperatureDataModel: Codable{
let id: Int?
let temperature: Double?
let humidty: Double?
let timeCaptured: String?
}
My function looks like this
func getTemperData(){
//Create the URLs
let temperatureDataUrl = URL(string: "https://weatherstationapi.azurewebsites.net/api/TemperatureSensor/GetData")
// let WindDataUrl = URL(string: "https://weatherstationapi.azurewebsites.net/api/WindData/GetAllData")
guard let requestURLTemp = temperatureDataUrl else { fatalError() }
//Create URL request
var request = URLRequest(url: requestURLTemp)
//Specifiy HTTP Method to use
request.httpMethod = "GET"
request.setValue("application/json", forHTTPHeaderField: "Accept")
request.setValue("Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJodHRwOi8vc2NoZW1hcy54bWxzb2FwLm9yZy93cy8yMDA1LzA1L2lkZW50aXR5L2NsYWltcy9uYW1lIjoiaWxpci50YWlyaUB0dHUuZWR1IiwiaHR0cDovL3NjaGVtYXMueG1sc29hcC5vcmcvd3MvMjAwNS8wNS9pZGVudGl0eS9jbGFpbXMvbmFtZWlkZW50aWZpZXIiOiI4MjEzYzhhMy1iODgxLTQ4NmUtOGUyMC1mZmNlMDlmNGY0ZjgiLCJuYmYiOiIxNjAyNTI2NDI1IiwiZXhwIjoiMTYwNTExODQyNSJ9.t1qnYyXLpRRJ3YQfhgLrylBqL_pdKOnKVMgOfG9IuVc", forHTTPHeaderField: "Authorization")
//Send HTTP Request
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
guard let data = data else {return}
print(data)
//Use parseJSON to convert data
let TemperatureData = parseJSON(data: data)
// for singleValue in TemperatureData {
// print(singleValue.temperautre)
// }
//read list
guard let TemperatureDataModel = TemperatureData else {return}
print("Temperature is : \(TemperatureDataModel.temperature)")
// Check if error took place
if let error = error {
print("Error took place \(error)")
return
}
//Read HTTP Response Status Code
// if let data = data, let dataString = String(data: data, encoding: .utf8) {
// print("Response data string:\n \(dataString)")
// }
}
task.resume()
}
and then my JSON decoder function looks like this
func parseJSON(data: Data) -> TemperatureDataModel? {
var returnValue: TemperatureDataModel?
do {
let returnValue = try JSONDecoder().decode([TemperatureDataModel].self, from: data)
} catch {
print("Error took place \(error).")
}
return returnValue
}
I've looked at 6+ stack overflow posts now and still cannot figure It out. Ive tried putting my model in [] for an array, moving where the function is called, changing the jsondecoder function and more and nothing works.
I think you have to give a format to the date before you parse the data
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
Your issue there is that you are creating another returnValue that is not being returned. You need also change the return type to [TemperatureDataModel]
func parseJSON(data: Data) -> [TemperatureDataModel]? {
do {
return try JSONDecoder().decode([TemperatureDataModel].self, from: data)
} catch {
print("Error took place \(error).")
return nil
}
}
so i wanna parse json api, but i the way i get that param to parse i need to fetch another json (which is working), and since i cant put that data param for my 2nd json api into global var so i can just put it into another func, i have this idea that i parse my 2nd json api inside the 1st urlSession, but i always get a nil callback,
override func viewDidLoad() {
super.viewDidLoad()
getRoom()
}
func getRoom() {
guard let url = URL(Some url) else {return}
print(url)
URLSession.shared.dataTask(with: url) { data, resp, err in
guard let data = data else {return}
do{
let decoder = JSONDecoder()
let room = try decoder.decode(User.self, from: data)
self.dataClient = [room].compactMap{$0!.data}
self.DATA = [room]
print("ini dataClient 🪕\(self.dataClient)")
let roomid = self.dataClient[0].RoomID
self.roomId = roomid
print(self.roomId)
DispatchQueue.main.async {
checkRoom()
}
}catch{
print(err!)
}
}.resume()
}
func checkRoom() {
if self.roomId == 0 {
print("roomId nil")
}else if self.roomId != 0{
print("ini room id \(self.roomId)")
guard let urlRoom = URL(some url) else {return
URLSession.shared.dataTask(with: urlRoom) { (data, resp, err) in
guard let data = data else {return}
do{
let decoder = JSONDecoder()
let roomAv = try decoder.decode(User.self, from: data)
self.DATA = [roomAv]
print("ini boolnya 🎸 \(self.DATA[0].success)")
print("Success")
}catch{
print("damn😭") // this line always get called
}
}.resume()
}
}
can anyone tell me any ideas? the reason i put the 2nd urlsession inside 1st urlsession because i need that (self.roomId) for my param in my 2nd Json api.
and when i try to separate both urlsession func in my checkRoom() alwasy called "roomId Nil"
I wouldn't make a call within a call personally. That's asking for trouble. Just call the first endpoint, get the data from it and pass in whatever you needed from that into the second call in your logic controller.
Quasi code:
import Foundation
class Test {
func getRoom() {
getFirstCall { [weak self] (foo) in
self?.getSecondCall(someArg: foo) {
// Handle data here.
}
}
}
func getFirstCall(completion: #escaping (_ somethingToReturn: String) -> ()) {
guard let url = URL(string: "Some URL") else { return }
URLSession.shared.dataTask(with: url) { data, response, error in
// Logic to ingest data.
completion("foo")
}.resume()
}
func getSecondCall(someArg: String, completion: #escaping () -> ()) {
guard let url = URL(string: "Some URL 2") else { return }
// Use "someArg" however you need in this call. queryParam, body, etc.
URLSession.shared.dataTask(with: url) { data, response, error in
// Logic to ingest data.
completion()
}.resume()
}
}
I have my controller like this -
def create
if (#user = User.find_by_email(params[:email])) && #user.valid_password?(params[:password])
render json: #user.as_json(only: [:email,:authentication_token]),status: :created
else
render json:('Unauthorized Access')
end
end
When I use Postman to make this request, I choose Body, and form data and adds in the email and password. And this WORKS
How to use swift to do the same? This is what I have tried
let url = URL(string: "http://localhost:3000/api/v1/user_serialized/")
let config = URLSessionConfiguration.default
let request = NSMutableURLRequest(url: url!)
request.httpMethod = "POST"
let bodyData = "email=Test#test.com&password=Test1234"
request.httpBody = bodyData.data(using: String.Encoding.utf8);
let session = URLSession(configuration: config)
let task = session.dataTask(with: url! as URL, completionHandler: {(data, response, error) in
let json = JSON(data:data!)
debugPrint(json)
})
task.resume()
I have made a Custom HTTP class where we can sent url, parameter and we will get Data from API. Below is the class.
import Foundation
//HTTP Methods
enum HttpMethod : String {
case GET
case POST
case DELETE
case PUT
}
class HttpClientApi: NSObject{
//TODO: remove app transport security arbitary constant from info.plist file once we get API's
var request : URLRequest?
var session : URLSession?
static func instance() -> HttpClientApi{
return HttpClientApi()
}
func makeAPICall(url: String,params: Dictionary<String, Any>?, method: HttpMethod, success:#escaping ( Data? ,HTTPURLResponse? , NSError? ) -> Void, failure: #escaping ( Data? ,HTTPURLResponse? , NSError? )-> Void) {
request = URLRequest(url: URL(string: url)!)
logging.print("URL = \(url)")
if let params = params {
let jsonData = try? JSONSerialization.data(withJSONObject: params, options: .prettyPrinted)
request?.setValue("application/json", forHTTPHeaderField: "Content-Type")
request?.httpBody = jsonData//?.base64EncodedData()
//paramString.data(using: String.Encoding.utf8)
}
request?.httpMethod = method.rawValue
let configuration = URLSessionConfiguration.default
configuration.timeoutIntervalForRequest = 30
configuration.timeoutIntervalForResource = 30
session = URLSession(configuration: configuration)
//session?.configuration.timeoutIntervalForResource = 5
//session?.configuration.timeoutIntervalForRequest = 5
session?.dataTask(with: request! as URLRequest) { (data, response, error) -> Void in
if let data = data {
if let response = response as? HTTPURLResponse, 200...299 ~= response.statusCode {
success(data , response , error as? NSError)
} else {
failure(data , response as? HTTPURLResponse, error as? NSError)
}
}else {
failure(data , response as? HTTPURLResponse, error as? NSError)
}
}.resume()
}
}
Now you can refer below code to get how to make an API call.
var paramsDictionary = [String:Any]()
paramsDictionary["username"] = "BBB"
paramsDictionary["password"] = "refef"
HttpClientApi.instance().makeAPICall(url: "Your URL", params:paramsDictionary, method: .POST, success: { (data, response, error) in
// API call is Successfull
}, failure: { (data, response, error) in
// API call Failure
})
I think you should pass your request instead of the url to session.dataTask
here is how my code looks like:
private let url = URL(string: "http://example.com/")!
func httpPost(jsonData: Data) {
if !jsonData.isEmpty {
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.httpBody = jsonData
URLSession.shared.getAllTasks { (openTasks: [URLSessionTask]) in
NSLog("open tasks: \(openTasks)")
}
let task = URLSession.shared.dataTask(with: request, completionHandler: { (responseData: Data?, response: URLResponse?, error: Error?) in
NSLog("\(response)")
})
task.resume()
}
}
Here is the Example of POST API for calling Login API with parameters "emailaddress" and "password" with userEmailID and Userpassword as two strings holding values for email and password respectively.
You can call this POST API anywhere in your view controller, as given below:
self.postLoginCall(url: "Your post method url") example: self.postLoginCall(url: "http://1.0.0.1/api/login.php")
func postLoginCall(url : String){
let request = NSMutableURLRequest(url: NSURL(string: url)! as URL)
request.httpMethod = "POST"
let postString = "emailaddress=\(userEmailID!)&password=\(Userpassword!)"
print(postString)
request.setValue("application/x-www-form-urlencoded; charset=utf-8", forHTTPHeaderField: "Content-Type")
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
}
do {
if let responseJSON = try JSONSerialization.jsonObject(with: data!) as? [String:AnyObject]{
print(responseJSON)
print(responseJSON["status"]!)
self.response1 = responseJSON["status"]! as! Int
print(self.response1)
//Check response from the sever
if self.response1 == 200
{
OperationQueue.main.addOperation {
//API call Successful and can perform other operatios
print("Login Successful")
}
}
else
{
OperationQueue.main.addOperation {
//API call failed and perform other operations
print("Login Failed")
}
}
}
}
catch {
print("Error -> \(error)")
}
}
task.resume()
}
Hello everyone I share below an example of a function to make a request in POST with SWIFT 5+.
This function allows you to send a POST request with an API entry point and parameters in the form of [[String: String]] and an Int to determine the output action.
For the output actions we call a function with Switch Case.
The operation is extremely simple. You have to put the two functions in one of your classes.
func MGSetRequestApi(endpoint: String, parameters: [[String: String]], MGSetAction: Int) -> String {
var setReturn: String!
let semaphore = DispatchSemaphore (value: 0)
var MGGetParam: String! = ""
for gate in parameters {
for (key, value) in gate {
let myParam = key + "=" + value + "&"
MGGetParam.append(contentsOf: myParam)
}
}
let postData = MGGetParam.data(using: .utf8)
var request = URLRequest(url: URL(string: endpoint)!,timeoutInterval: 10000)
request.addValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
request.httpMethod = "POST"
request.httpBody = postData
let task = URLSession.shared.dataTask(with: request) { data, response, error in
guard let data = data else {
print(String(describing: error))
semaphore.signal()
return
}
print(String(data: data, encoding: .utf8)!)
setReturn = String(data: data, encoding: .utf8)!
DispatchQueue.main.async {
self.MGRequestAction(MGGetIdRq: MGSetAction, MGGetData: setReturn)
}
semaphore.signal()
}
task.resume()
semaphore.wait()
return setReturn
}
Then implement this function to manage the outputs
func MGRequestAction(MGGetIdRq: Int, MGGetData: String) {
switch MGGetIdRq {
case 1:
// Do something here
case 2:
// Do something else here
case 3:
// Do something else here again
default:
print("Set default action");
}
}
How to use this, you have two possibilities, the first one is to process what the function
MGSetRequestApi(endpoint: String, parameters: [[String: String]], MGSetAction: Int) -> String
returns (String) or to pass by the function
MGRequestAction(MGGetIdRq: Int, MGGetData: String)
which will call your Json parse function.
The MGRequestAction() function takes for parameter an Int for the choice of the action and the String of the return of the request
Now to use it do like this:
_ = MGSetRequestApi(endpoint: MY_END_POINT_API,
parameters: [["KEY_1": "VALUE 1"],
["KEY_2": "VALUE 2"],
["KEY_3": "VALUE 3"],
["KEY_4": "VALUE 4"]],
MGSetAction: 3)
I'm converting a project from Obj-c to Swift 3 and I can't get it to read JSON responses from our web methods. As far as I can see, the code looks like a good conversion from it's Obj-c counterpart, but the JSONSerilaization is having trouble.
I would post the old Obj-c, but it's spread across several NSURLConnection delegate methods. I can post this if required?
Swift 3:
// Set up the URL request
var getString : String = "https://TheWebMethod"
guard let url = URL(string: getString) else {
print("Error: cannot create URL")
return
}
let urlRequest = URLRequest(url: url)
// set up the session
let config = URLSessionConfiguration.default
let session = URLSession(configuration: config)
// make the request
let task = session.dataTask(with: urlRequest) {
(data, response, error) in
// check for any errors
guard error == nil else {
print("error calling GET on Method")
print(error)
return
}
// make sure we got data
guard let responseData = data else {
print("Error: did not receive data")
return
}
// parse the result as JSON, since that's what the API provides
do {
guard let result = try JSONSerialization.jsonObject(with: responseData, options: []) as? [String: AnyObject] else {
print("error trying to convert data to JSON")
return
}
print("The result is: " + result.description)
guard let resultTitle = result["title"] as? String else {
print("Could not get title from JSON")
return
}
print("The title is: " + resultTitle)
} catch {
print("error trying to convert data to JSON")
return
}
}
task.resume()
Example JSON output when run through browser:
[{"id":"3","Initials":"TL","FullName":"Tony Law","LoginName":"test","Password":"password","EmailAddress":"myemailaddress","MobileTelNo":"0123456789","SecToken":"Secret"}]