Not getting result in NSURLSession in swift - swift2

In using swift 2.2, while using NSURLSession I am not getting the Response. What am I doing wrong?
I have to pass parameters and header in POST request.
func API() {
let userName:String! = "uname"
let password:String! = "password"
let request = NSMutableURLRequest(URL: NSURL(string: URL)!)
request.HTTPMethod = "POST"
let data = try! NSJSONSerialization.dataWithJSONObject(parameter, options:[])
let json = NSString(data: data, encoding: NSUTF8StringEncoding) as! String
request.HTTPBody = json.dataUsingEncoding(NSUTF8StringEncoding)
request.allHTTPHeaderFields = ["key":"value"]
let task = NSURLSession.sharedSession().dataTaskWithRequest(request) { data, response, error in
guard error == nil && data != nil else { // check for fundamental networking error
print("error=\(error)")
return
}
if let httpStatus = response as? NSHTTPURLResponse where 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: NSUTF8StringEncoding)
print("responseString = \(responseString)")
}
task.resume()
}
Result is:
responseString = Optional("")

Did you call this service on any REST client like Postman ? if yes and get response so try replace this line
request.allHTTPHeaderFields = ["key":"value"]
with this
request.setValue("value",forHTTPHeaderField:"Key")
and set all values

Related

Converting a short URL to a full url in swift 5

Hello I'm trying to convert a short URL like https://goo.gl/maps/MoaZNS825rpixfKu5 to its original URL https://www.google.com/maps/place/WhirlyBall+Twin+Cities/#44.8508658,-93.2389179,17z/data=!3m1!4b1!4m5!3m4!1s0x87f62f7bd688277b:0xc0ec9f7b1ccd0da8!8m2!3d44.8510743!4d-93.2366811?hl=en-US
I found some solutions in similar old posts but they are not working with Xcode 12.4
I tried using the below code but it didn't return any value when I try to print expandedURL
let shortURL = "https://goo.gl/maps/MoaZNS825rpixfKu5"
func performRequest(urlString: String){
let urlString = shortURL
let url = URL(string: urlString)!
var urlRequest = URLRequest(url: url)
urlRequest.httpMethod = "HEAD"
URLSession.shared.dataTask(with: urlRequest) { (data, urlResponse, error) in
let expandedURL = urlResponse?.url?.absoluteString
print("expandedURL HEAD: \(expandedURL ?? "Oops, not URL")")
}
.resume()
}
I managed to get it to work with the below code
I know it's somehow a primitive way but it just worked with me :)
let shortURL = //"https://goo.gl/maps/MoaZNS825rpixfKu5"
"https://goo.gl/maps/xNdKp1Q1KqFeWQv99"
performRequest (urlString: shortURL)
func performRequest(urlString: String){
if let url = URL(string: urlString){
let session = URLSession(configuration: .default)
var urlRequest = URLRequest(url: url)
urlRequest.httpMethod = "HEAD"
let task = session.dataTask(with: urlRequest, completionHandler: handle(data:response:error:))
task.resume()
}
}
func handle (data: Data?, response: URLResponse?, error: Error?){
if error != nil {
print (error)
return
}
if let safeData = data {
let dataString = String(data: safeData, encoding: .utf8)
let expandedURL = response?.url?.absoluteString
print(expandedURL!)
}
}

Xcode Error Ambiguous reference to member 'dataTask(with:completionHandler:)' [duplicate]

This question already has answers here:
Swift 3 URLSession.shared() Ambiguous reference to member 'dataTask(with:completionHandler:) error (bug)
(14 answers)
Closed 6 years ago.
I have a swift 2.3 project I just updated to swift 3.0 and the following code broke.
let task = URLSession.shared.dataTask(with: request, completionHandler: {
data, response, error in
if error != nil {
print("error=\(error)")
return
}
print("response = \(response)")
let responseString = NSString(data: data!, encoding: String.Encoding.utf8)
print("responseString = \(responseString)")
})
task.resume()
I am unaware how to fix it
You can get that error if the request is a NSURLRequest rather than a URLRequest.
let url = URL(string: urlString)!
let request = URLRequest(url: url)
let task = URLSession.shared.dataTask(with: request) { data, response, error in
guard let data = data, error == nil else {
print("error=\(error)")
return
}
print("response = \(response)")
let responseString = String(data: data, encoding: .utf8)
print("responseString = \(responseString)")
}
task.resume()
Or, if you're mutating the URLRequest, use var:
let url = URL(string: urlString)!
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.httpBody = ...
let task = URLSession.shared.dataTask(with: request) { data, response, error in
guard let data = data, error == nil else {
print("error=\(error)")
return
}
print("response = \(response)")
let responseString = String(data: data, encoding: .utf8)
print("responseString = \(responseString)")
}
task.resume()
Also, note, I've replaced NSString with String.

how to make http post json request params using swift 2.0

i need to send the json request parameters to the server using nsurl session in swift2.0. i don't know how to create the json request params.i created the params like this
let jsonObj = ["Username":"Admin", "Password":"123","DeviceId":"87878"]
// print("Params are \(jsonObj)")
//request.HTTPBody = try! NSJSONSerialization.dataWithJSONObject(jsonObj, options: [])
// or if you think the conversion might actually fail (which is unlikely if you built `params` yourself)
do {
request.HTTPBody = try NSJSONSerialization.dataWithJSONObject(jsonObj, options:.PrettyPrinted)
} catch {
print(error)
}
but its not ping to the method body so i am getting the failure response
Try the below code.
let parameters = ["Username":"Admin", "Password":"123","DeviceId":"87878"] as Dictionary<String, String>
let request = NSMutableURLRequest(URL: NSURL(string:YOURURL)!)
let session = NSURLSession.sharedSession()
request.HTTPMethod = "POST"
//Note : Add the corresponding "Content-Type" and "Accept" header. In this example I had used the application/json.
request.addValue("application/json", forHTTPHeaderField: "Content-Type")
request.addValue("application/json", forHTTPHeaderField: "Accept")
request.HTTPBody = try! NSJSONSerialization.dataWithJSONObject(parameters, options: [])
let task = session.dataTaskWithRequest(request) { data, response, error in
guard data != nil else {
print("no data found: \(error)")
return
}
do {
if let json = try NSJSONSerialization.JSONObjectWithData(data!, options: []) as? NSDictionary {
print("Response: \(json)")
} else {
let jsonStr = NSString(data: data!, encoding: NSUTF8StringEncoding)// No error thrown, but not NSDictionary
print("Error could not parse JSON: \(jsonStr)")
}
} catch let parseError {
print(parseError)// Log the error thrown by `JSONObjectWithData`
let jsonStr = NSString(data: data!, encoding: NSUTF8StringEncoding)
print("Error could not parse JSON: '\(jsonStr)'")
}
}
task.resume()
Hope it works for you!!

running 2 tasks on one NSURLSession.sharedSession

I am trying to do 2 HTTP requests
in the first request i will get a var that will be used in the second request.
My problem is when I do it using the code below it just runs the second request without running the first.
let url = NSURL(string:"https://loginurl")
let cachePolicy = NSURLRequestCachePolicy.ReloadIgnoringLocalCacheData
let request = NSMutableURLRequest(URL: url!, cachePolicy: cachePolicy, timeoutInterval: 2.0)
request.HTTPMethod = "POST"
let contentType = " application/x-www-form-urlencoded"
NSURLProtocol.setProperty(contentType, forKey: "Content-Type", inRequest: request)
var dataString = "user details"
var requestBodyData = (dataString as NSString).dataUsingEncoding(NSUTF8StringEncoding)
request.HTTPBody = requestBodyData
NSURLProtocol.setProperty(requestBodyData!.length, forKey: "Content-Length", inRequest: request)
var response: NSURLResponse?
let session = NSURLSession.sharedSession()
var task = session.dataTaskWithRequest(request, completionHandler: {data, response, error -> Void in
//code for getting the session id to be used in the second request
})
task.resume()
let url2 = NSURL(string:"http://url2?sessionid")
let request2 = NSMutableURLRequest(URL: url2!, cachePolicy: cachePolicy, timeoutInterval: 2.0)
request2.HTTPMethod = "GET"
dataString=""
requestBodyData = (dataString as NSString).dataUsingEncoding(NSUTF8StringEncoding)
request2.HTTPBody = requestBodyData
NSURLProtocol.setProperty(contentType, forKey: "Content-Type", inRequest: request2)
task = session.dataTaskWithRequest(request2, completionHandler: {data, response, error -> Void in
})
task.resume()
Can anybody explain what can be wrong with this code
Problem 2:
let task = session.dataTaskWithRequest(request, completionHandler: {data, response, error -> Void in
if let httpRes = response as? NSHTTPURLResponse {
let html = NSString(data:data!, encoding:NSUTF8StringEncoding)
if let match = html?.rangeOfString("(?<=sessionid=')[^\';]+", options: .RegularExpressionSearch) {
portalid = (html?.substringWithRange(match))!
}
}
When I run in simulator it works without issues but when I debug it on iPhone it crashes showing this error "Terminating app due to uncaught exception 'NSRangeException', reason: '-[__NSCFString substringWithRange:]: Range {9223372036854775807, 0} out of bounds; string length 52427'"
Thanks
Here is code sample which makes two requests:
//: Playground - noun: a place where people can play
import UIKit
import XCPlayground
XCPlaygroundPage.currentPage.needsIndefiniteExecution = true
let session = NSURLSession.sharedSession()
session.dataTaskWithURL(NSURL(string: "http://www.google.com")!, completionHandler: { (data :NSData?, response :NSURLResponse?, error :NSError?) -> Void in
let res = NSString(data: data!, encoding: NSUTF8StringEncoding)
print(res!)
// make a new request here
let innerSession = NSURLSession.sharedSession()
innerSession.dataTaskWithURL(NSURL(string: "http://www.google.com")!, completionHandler: { (data :NSData?, response :NSURLResponse?, error :NSError?) -> Void in
let res = NSString(data: data!, encoding: NSUTF8StringEncoding)
print(res!)
}).resume()
}).resume()

Swift callback in dataTaskWithRequest

New to Swift and trying to write a login screen for my app.
My controller:
#IBAction func loginButton(sender: UIButton) {
let emailAddress = emailTextField.text
let password = passwordTextField.text
let api = Api()
api.authenticate(emailAddress!, password: password!)
}
Api class:
class Api {
func authenticate(username: String, password: String) -> Bool {
var params = [String: String]()
params["username"] = username
params["password"] = password
params["grant_type"] = "password"
var headers = [String: String]()
headers["Content-Type"] = "application/x-www-form-urlencoded"
post("authenticate", params: params, headers: headers) {data, response in
// do something
}
}
func post(location: String, params: [String: String], headers: [String: String], callback: ((data: NSString!, response: NSHTTPURLResponse) -> Void)) {
let request = NSMutableURLRequest()
let session = NSURLSession.sharedSession()
request.URL = NSURL(string: Configuration.apiBaseUrl + location)
request.HTTPMethod = "POST"
request.HTTPBody = NSString(string: getPostBody(params)).dataUsingEncoding(NSUTF8StringEncoding)
request.addValue("Basic " + Configuration.apiAuthorization, forHTTPHeaderField: "Authorization")
for (key, value) in headers {
request.addValue(value, forHTTPHeaderField: key)
}
let task = session.dataTaskWithRequest(request, completionHandler: {data, response, error -> Void in
let data = NSString(data: data!, encoding: NSUTF8StringEncoding)
let httpResponse = response as! NSHTTPURLResponse
callback(data: data, response: httpResponse)
return
})
task.resume()
}
}
As I plan to add more API methods after authentication, I want generic POST/PUT/GET/DELETE methods. I am trying to understand how I can best set up the callbacks in Swift so the post call in the authenticate method can return true/false and show like a dialog on the UI thread. Returning a boolean in the post call in the authenticate method is not allowed now, because it expects Void.
I am familiar with callbacks in nodejs and trying to grasp this now. Any hints what the best approach would be?

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