Sending get request in swift 4

getRequestSwift4.swift

import Foundation

enum Result<T> {
    case success(T)
    case failure(Error)
}

class Service: ServiceProtocol {
    func get(callback: @escaping ((Result<[MyObject]>) -> ())) {
        let url = URL(string: Links.baseUrl)!
        var request = URLRequest(url: url)
        request.httpMethod = "GET"
        
        let config = URLSessionConfiguration.default
        let session = URLSession(configuration: config)
        let task = session.dataTask(with: request) { (responseData, response, responseError) in
            DispatchQueue.main.async {
                if let error = responseError {
                    callback(.failure(error))
                } else if let jsonData = responseData {
                    
                    let decoder = JSONDecoder()
                    do {
                        let objects = try decoder.decode([MyObject].self, from: jsonData)
                        callback(.success(objects))
                    } catch {
                        callback(.failure(error))
                    }
                } else {
                    let error = NSError(domain: "", code: 0, userInfo: [NSLocalizedDescriptionKey : "Data was not retrieved from request"]) as Error
                    callback(.failure(error))
                }
            }
        }
        
        task.resume()
    }
}