Handling re-direction with URLSession (Swift)

MyAPI.swift

import UIKit

@objc class MyAPI: NSObject {
    
    static let keyError: String = "Error"
    static let keyResult: String = "Result"
  
    static let unknownError: String = "Unknown error"
    
    static let notificationMyAPIDidEnd = Notification.Name(rawValue: "notificationMyAPIDidEnd")
    static let notificationMyAPIDidFail = Notification.Name(rawValue: "notificationMyAPIDidFail")
    
    // MARK: - Constructor -
    static let sharedInstance = MyAPI()
    
    var session: URLSession?
    
    let headers = [
        "authorization": "Basic my_authorization_token",
        "cache-control": "no-cache",
    ]
    
    fileprivate override init() {
        super.init()
        
        let sessionConfig: URLSessionConfiguration = URLSessionConfiguration.default
        session = URLSession(configuration: sessionConfig, delegate: self, delegateQueue: nil)
    }
        
    func myAPICall(urlString: String) {
        
        let request = NSMutableURLRequest(url: NSURL(string: urlString)! as URL,
                                          cachePolicy: .useProtocolCachePolicy,
                                          timeoutInterval: 10.0)
        request.httpMethod = "GET"
        request.allHTTPHeaderFields = headers
        
        let dataTask = session?.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
            if (error != nil) {
                DispatchQueue.main.async {
                    NotificationCenter.default.post(name: MyAPI.notificationMyAPIDidFail, object: [MyAPI.keyError:(error?.localizedDescription ?? MyAPI.unknownError)])
                }
            } else {
                if let httpResponse: HTTPURLResponse = response as? HTTPURLResponse {
                    if (httpResponse.statusCode >= 200) && (httpResponse.statusCode < 300) {
                        if let data = data,
                            let json = try? JSONSerialization.jsonObject(with: data, options: []) as? [String: Any] {
                            if let resultDict: [String:Any] = json {
                                if resultDict.count > 0 {
                                    let responseDic: [String: Any] = [MyAPI.keyResult: resultDict]
                                        
                                    DispatchQueue.main.async {
                                      NotificationCenter.default.post(name: MyAPI.notificationMyAPIDidEnd, object: responseDic)
                                    }
                                    
                                    return
                                }
                            }
                        }
                    }
                }
            }
        })
        
        dataTask?.resume()
    }
}

extension MyAPI: URLSessionDelegate, URLSessionTaskDelegate {
    
    func urlSession(_ session: URLSession, task: URLSessionTask, willPerformHTTPRedirection response: HTTPURLResponse, newRequest request: URLRequest, completionHandler: @escaping (URLRequest?) -> Swift.Void) {
    
        // The original request was redirected to somewhere else.
        // We create a new dataTask with the given redirection request and we start it.
        if let urlString = request.url?.absoluteString {
            self.myAPICall(urlString)
        } else {
            DispatchQueue.main.async {
                NotificationCenter.default.post(name: MyAPI.notificationMyAPIDidFail, object: [MyAPI.keyError:MyAPI.unknownError])
            }
        }
    }

}