ios - Cannot get data from Alamofire return - ios

I want to get the data from server api using Alamofire call. But after the api function executed, the data return is empty because Swift is asynchronous...
This code is call the server api:
func getAllModels(completion: #escaping (_ result: [String]?) -> ()) {
var _modelList:[String] = []
let url = BASE_URL + "getAllProductAndModelv2"
Alamofire.request(url, method:.get, parameters: [:], encoding: JSONEncoding.default).responseJSON { response in
switch response.result {
case .success:
if((response.result.value) != nil) {
let data = NSData(contentsOf: URL(string: url)!)
do {
if let data = data, let json = try JSONSerialization.jsonObject(with: data as Data) as? [String: Any], let models = json["models"] as? [[String:Any]] {
for model in models {
if let name = model["name"] as? String {
_modelList.append(name)
}
}
}
}catch {
print("error")
}
completion(_modelList)
}
case .failure(let error):
print(error)
completion(nil)
}
}
}
And this code is get data from getAllModels function:
var models:[VirtualObject] = []
RestApiManager().getAllModels(){ (result) -> () in
print("************************************************")
if let result = result {
var array = result as Array
for item in array {
print(item)
models.append(VirtualObject(url: URL(string: item)!)!)
}
}
print("************************************************")
}
print(models)
return models
I don't know how to use the callback function exactly to bind the data to return model.. Please help!

Use didSet observer of variables. And call api in viewDidload.
class ViewController: UIViewController {
var arrModals = [Any]() {
didSet {
print("this call when get all modals from server")
}
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
RestApiManager().getAllModels(){ (result) -> () in
var arrTempModals = [Any]()
if let result = result {
var array = result as Array
for item in array {
print(item)
arrTempModals.append(item)
}
}
self.arrModals = arrTempModals
}
}
}

Related

JSON Decoding Not Populating Table View

I am trying to parse data from the website movieDatabase.com However there's some issue decoding the data to json and populating my table view.I am not sure why this is happening. Please I need help spotting out the problem. Here's my code. https://github.com/lexypaul13/Movie-Browser/tree/main/Movie-Browser
struct Movies: Codable {
let overview:String?
let original_title: String?
let poster_path:String
}
struct ApiResponse:Codable, Hashable {
let page:Int
let shows:[Movies]
enum CodingKeys:String, CodingKey {
case page = "page"
case shows = "results"
}
}
class NetworkManger{
enum EndPoint{
case showList
}
static let shared = NetworkManger()
private let baseURL : String
private var apiKeyPathCompononent :String
private init(){
self.baseURL = "https://api.themoviedb.org/3/movie/now_playing?"
self.apiKeyPathCompononent = "api_key=a07e22bc18f5cb106bfe4cc1f83ad8ed"
}
private var jsonDecoder:JSONDecoder = {
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
return decoder
}()
func get<T:Decodable>(_ endPoints: EndPoint, urlString: String, completed:#escaping(Result<T?,ErroMessage>)->Void){
guard let url = urlBuilder(endPoint: endPoints) else {
completed(.failure(.invalidURL))
return
}
let task = URLSession.shared.dataTask(with: url){ data, response, error in
if let _ = error {
completed(.failure(.unableToComplete))
return
}
guard let response = response as? HTTPURLResponse, response.statusCode==200 else {
print(ErroMessage.invalidResponse.rawValue)
completed(.failure(.invalidResponse))
return
}
guard let data = data else{
completed(.failure(.invalidData))
return
}
do{
let apiResponse = try self.jsonDecoder.decode([T].self, from: data)
DispatchQueue.main.async {
completed(.success(apiResponse as? T))
}
} catch{
print(ErroMessage.invalidData.rawValue)
}
}
task.resume()
}
private func urlBuilder(endPoint:EndPoint )->URL?{
switch endPoint {
case .showList:
return URL(string: baseURL + apiKeyPathCompononent )
}
}
func getMovies(){
NetworkManger.shared.get(.showList, urlString: "") { [weak self] (result: Result<[Movies]?,ErroMessage> ) in
guard let self = self else { return }
switch result{
case .success(let movies):
self.movies = movies ?? []
DispatchQueue.main.async {self.tableView.reloadData()}
case .failure(let error):
print(error.localizedDescription)
}
}
}
}
The root object returned from the api is your ApiResult struct. This contains an array of movies (which you have mapped to the shows property of the ApiResult)
You need to change the getMovies function so that the right generic type can be inferred and the json decoder can do the right thing
func getMovies(){
NetworkManger.shared.get(.showList, urlString: "") { [weak self] (result: Result<ApiResult,ErroMessage> ) in
guard let self = self else { return }
switch result{
case .success(let apiResult):
self.movies = apiResult.shows
DispatchQueue.main.async {self.tableView.reloadData()}
case .failure(let error):
print(error.localizedDescription)
}
}
}

passing data (json) to another controller in swift 5.2 con Alamofire

I have a Login view that asks for a card and password. I consult an API and if the entered data is correct, it sends me a JSON like this. Which return has the button method? How do I send that data to the other view? I occupy Alamofire 5.0 and have my Model class.
#IBAction func myButtonIngresarAction(_ sender: Any) {
guard let carnet = self.txtCarnet.text else {return}
guard let contrasena = self.txtPassword.text else {return}
let ingresologinmodel = IngresoLoginModel(usuario: carnet, password: contrasena)
self.apiCall(IngresoLoginModel: ingresologinmodel){
(result) in
switch result{
case .success(let json):
print(json)
**//This is where I want to send that json with the data to the other view. ******
case .failure(let err):
print(err.localizedDescription)
}
}
}
enum ApiErros: Error {
case custom(message : String)
}
typealias Handler = (Swift.Result<Any?, ApiErros>) -> Void
func apiCall(IngresoLoginModel: IngresoLoginModel, completionHandler: #escaping Handler)
{
let header: HTTPHeaders = [
.contentType("application/json")
]
AF.request("https://url/xxxx/api/Login", method: .post, parameters: IngresoLoginModel,
encoder: JSONParameterEncoder.default, headers: header).response{ response in
debugPrint(response)
switch response.result{
case .success(let data):
do{
let json = try JSONDecoder().decode([LoginModel].self, from: data!)
print(json)
if response.response?.statusCode == 200{
completionHandler(.success(json))
}else{
completionHandler(.failure(.custom(message: "Por favor verifica tu internet")))
}
}
catch
{
print(error)
completionHandler(.failure(.custom(message: "Problemas")))
}
case .failure(let err):
print(err.localizedDescription)
}
}
}
Class model
struct LoginModel: Codable {
let idEmpleado: Int
let Nombre: String
let CodEmpleado: String
let password: String
let idPerfil: Int
let activo: Int
let Descripcion: String
let idRegion: Int
let correo: String
}
This is the json that the Api sends me the data changes them for these example
{
"idEmpleado": 1,
"nombre": “test”,
"codEmpleado": “000000”,
"password": “123”,
"idPerfil": 4,
"activo": 1,
"Descripcion": “test”,
"idregion": 1,
"correo": “test#test.com"
}
many way like create a variable to save this json in OtherViewController and call, self?.otherViewController.json = json
https://learnappmaking.com/pass-data-between-view-controllers-swift-how-to/
use didSet
var page = [Datas]() {
didSet {
self.myVariable = page[0].date!
}
}
typealias Handler = (Swift.Result <[LoginModel]?, ApiErros>) -> Void
#IBAction func myButtonIngresarAction(_ sender: Any) {
guard let carnet = self.txtCarnet.text else {return}
guard let contrasena = self.txtPassword.text else {return}
let ingresologinmodel = IngresoLoginModel(usuario: carnet, password: contrasena)
self.apiCall(IngresoLoginModel: ingresologinmodel){
(result) in
switch result{
case .success(let json):
print(json)
//Here is that I do not know how to send it to the other controller all the json
let viewControllerB = HomeMenuViewController()
viewControllerB.datosPersonales = json!
self.navigationController?.pushViewController(viewControllerB, animated: true)
case .failure(let err):
print(err.localizedDescription)
}
}
}
second controller
class HomeMenuViewController: UIViewController {
#IBOutlet weak var mylabel: UILabel!
var datosPersonales = [LoginModel]()
override func viewDidLoad() {
super.viewDidLoad()
print("***************")
print(datosPersonales)
print("***************")
}
}

Codable for API request

How would I make this same API request through codables?
In my app, this function is repeated in every view that makes API calls.
func getOrders() {
DispatchQueue.main.async {
let spinningHUD = MBProgressHUD.showAdded(to: self.view, animated: true)
spinningHUD.isUserInteractionEnabled = false
let returnAccessToken: String? = UserDefaults.standard.object(forKey: "accessToken") as? String
let access = returnAccessToken!
let headers = [
"postman-token": "dded3e97-77a5-5632-93b7-dec77d26ba99",
"Authorization": "JWT \(access)"
]
let request = NSMutableURLRequest(url: NSURL(string: "https://somelink.com")! as URL,
cachePolicy: .useProtocolCachePolicy,
timeoutInterval: 10.0)
request.httpMethod = "GET"
request.allHTTPHeaderFields = headers
let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
if (error != nil) {
print(error!)
} else {
if let dataNew = data, let responseString = String(data: dataNew, encoding: .utf8) {
print("----- Orders -----")
print(responseString)
print("----------")
let dict = self.convertToDictionary(text: responseString)
print(dict?["results"] as Any)
guard let results = dict?["results"] as? NSArray else { return }
self.responseArray = (results) as! [HomeVCDataSource.JSONDictionary]
DispatchQueue.main.async {
spinningHUD.hide(animated: true)
self.tableView.reloadData()
}
}
}
})
dataTask.resume()
}
}
I would suggest to do the following
Create Base Service as below
import UIKit
import Foundation
enum MethodType: String {
case get = "GET"
case post = "POST"
case put = "PUT"
case patch = "PATCH"
case delete = "DELETE"
}
class BaseService {
var session: URLSession!
// MARK: Rebuilt Methods
func FireGenericRequest<ResponseModel: Codable>(url: String, methodType: MethodType, headers: [String: String]?, completion: #escaping ((ResponseModel?) -> Void)) {
UIApplication.shared.isNetworkActivityIndicatorVisible = true
// Request Preparation
guard let serviceUrl = URL(string: url) else {
print("Error Building URL Object")
return
}
var request = URLRequest(url: serviceUrl)
request.httpMethod = methodType.rawValue
// Header Preparation
if let header = headers {
for (key, value) in header {
request.setValue(value, forHTTPHeaderField: key)
}
}
// Firing the request
session = URLSession(configuration: URLSessionConfiguration.default)
session.dataTask(with: request) { (data, response, error) in
DispatchQueue.main.async {
UIApplication.shared.isNetworkActivityIndicatorVisible = false
}
if let data = data {
do {
guard let object = try? JSONDecoder().decode(ResponseModel.self , from: data) else {
print("Error Decoding Response Model Object")
return
}
DispatchQueue.main.async {
completion(object)
}
}
}
}.resume()
}
private func buildGenericParameterFrom<RequestModel: Codable>(model: RequestModel?) -> [String : AnyObject]? {
var object: [String : AnyObject] = [String : AnyObject]()
do {
if let dataFromObject = try? JSONEncoder().encode(model) {
object = try JSONSerialization.jsonObject(with: dataFromObject, options: []) as! [String : AnyObject]
}
} catch (let error) {
print("\nError Encoding Parameter Model Object \n \(error.localizedDescription)\n")
}
return object
}
}
the above class you may reuse it in different scenarios adding request object to it and passing any class you would like as long as you are conforming to Coddle protocol
Create Model Conforming to Coddle protocol
class ExampleModel: Codable {
var commentId : String?
var content : String?
//if your JSON keys are different than your property name
enum CodingKeys: String, CodingKey {
case commentId = "CommentId"
case content = "Content"
}
}
Create Service to the specific model with the endpoint constants subclassing to BaseService as below
class ExampleModelService: BaseService<ExampleModel/* or [ExampleModel]*/> {
func GetExampleModelList(completion: ((ExampleModel?)/* or [ExampleModel]*/ -> Void)?) {
super.FireRequestWithURLSession(url: /* url here */, methodType: /* method type here */, headers: /* headers here */) { (responseModel) in
completion?(responseModel)
}
}
}
Usage
class MyLocationsController: UIViewController {
// MARK: Properties
// better to have in base class for the controller
var exampleModelService: ExampleModelService = ExampleModelService()
// MARK: Life Cycle Methods
override func viewDidLoad() {
super.viewDidLoad()
exampleModelService.GetExampleModelList(completion: { [weak self] (response) in
// model available here
})
}
}
Basically, you need to conform Codable protocol in your model classes, for this you need to implement 2 methods, one for code your model and another for decode your model from JSON
func encode(to encoder: Encoder) throws
required convenience init(from decoder: Decoder) throws
After that you will be able to use JSONDecoder class provided by apple to decode your JSON, and return an array (if were the case) or an object of your model class.
class ExampleModel: Codable {
var commentId : String?
var content : String?
//if your JSON keys are different than your property name
enum CodingKeys: String, CodingKey {
case commentId = "CommentId"
case content = "Content"
}
}
Then using JSONDecoder you can get your model array like this
do {
var arrayOfOrders : [ExampleModel] = try JSONDecoder().decode([ExampleModel].self, from: dataNew)
}
catch {
}
First of all, I can recommend you to use this application -quicktype- for turning json file to class or struct (codable) whatever you want. enter link description here.
After that you can create a generic function to get any kind of codable class and return that as a response.
func taskHandler<T:Codable>(type: T.Type, useCache: Bool, urlRequest: URLRequest, completion: #escaping (Result<T, Error>) -> Void) {
let task = URLSession.shared.dataTask(with: urlRequest) { (data, response, error) in
if let error = error {
print("error : \(error)")
}
if let data = data {
do {
let dataDecoded = try JSONDecoder().decode(T.self, from: data)
completion(.success(dataDecoded))
// if says use cache, let's store response data to cache
if useCache {
if let response = response as? HTTPURLResponse {
self.storeDataToCache(urlResponse: response, urlRequest: urlRequest, data: data)
}
}
} catch let error {
completion(.failure(error))
}
} else {
completion(.failure(SomeError))
}
}
task.resume()
}

Alamofire Web service manager returns nil in viewController

I want to create AlamofireWebService manager that contains all of my requests and I just use class functions of this class in my viewControllers and use responses in the viewController.
For example something like this in viewController:
let cardResponse : String?
cardResponse = WebServiceManager.shared.getCardTitle()
I searched and found I should use escaping completionHandler in my function, And I wrote this:
import Foundation
import Alamofire
import SwiftyJSON
class WebServiceManager {
static let shared : WebServiceManager = WebServiceManager()
let apiEndPoint = "My URL"
func getCardTitle(completionHandler: #escaping (NSDictionary?, Error?) -> ()) {
Alamofire.request("\(apiEndPoint)")
.responseJSON { response in
switch response.result {
case .success(let value):
print("from .success \(value)")
completionHandler(value as? NSDictionary, nil)
case .failure(let error):
completionHandler(nil, error)
}
}
}
}
In success case, print works fine but in viewController, it just prints nil.
My viewController:
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
WebServiceManager.shared.getCardTitle() { responseObject, error in
// use responseObject and error here
print("responseObject = \(responseObject); error = \(error)")
return
}
}
What should I do to print in viewController print my response?
It means that your value can't be cast to NSDictionary it has another type.
completionHandler(value as? NSDictionary, nil)
Please try in the manager a "pseudo code"
if let dic = value as? [String: Any] {
debugPrint("Dic \(dic)")
} else if let str = value as? String {
debugPrint("String \(str)")
} else if let data = value as? Data, let str = String(data: data, encoding: .utf8) {
debugPrint("UTF8 String \(str)")
}
just check response nil
Alamofire.request("URL", method: .post).responseJSON{(responseData) -> Void in
if((responseData.result.value != nil)){
let jsonData = JSON(responseData.result.value)
if let arrJSON = jsonData["keyNodes"].arrayObject {
for index in 0...arrJSON.count-1 {
let aObject = arrJSON[index] as! [String : AnyObject]
var sl:String;
if let sl1 = aObject["sl"] as? String {
sl = sl1;
}
}
}
}
}

Deserialize a JSON array to a Swift array of objects

I am new to Swift, and am not able to figure out how to deserialize a JSON array to an array of Swift objects. I'm able to deserialize a single JSON user to a Swift user object fine, but just not sure how to do it with a JSON array of users.
Here is my User.swift class:
class User {
var id: Int
var firstName: String?
var lastName: String?
var email: String
var password: String?
init (){
id = 0
email = ""
}
init(user: NSDictionary) {
id = (user["id"] as? Int)!
email = (user["email"] as? String)!
if let firstName = user["first_name"] {
self.firstName = firstName as? String
}
if let lastName = user["last_name"] {
self.lastName = lastName as? String
}
if let password = user["password"] {
self.password = password as? String
}
}
}
Here's the class where I'm trying to deserialize the JSON:
//single user works.
Alamofire.request(.GET, muURL/user)
.responseJSON { response in
if let user = response.result.value {
var swiftUser = User(user: user as! NSDictionary)
}
}
//array of users -- not sure how to do it. Do I need to loop?
Alamofire.request(.GET, muURL/users)
.responseJSON { response in
if let users = response.result.value {
var swiftUsers = //how to get [swiftUsers]?
}
}
The best approach is the use Generic Response Object Serialization provided by Alamofire here is an example :
1) Add the extension in your API Manager or on a separate file
public protocol ResponseObjectSerializable {
init?(response: NSHTTPURLResponse, representation: AnyObject)
}
extension Request {
public func responseObject<T: ResponseObjectSerializable>(completionHandler: Response<T, NSError> -> Void) -> Self {
let responseSerializer = ResponseSerializer<T, NSError> { request, response, data, error in
guard error == nil else { return .Failure(error!) }
let JSONResponseSerializer = Request.JSONResponseSerializer(options: .AllowFragments)
let result = JSONResponseSerializer.serializeResponse(request, response, data, error)
switch result {
case .Success(let value):
if let
response = response,
responseObject = T(response: response, representation: value)
{
return .Success(responseObject)
} else {
let failureReason = "JSON could not be serialized into response object: \(value)"
let error = Error.errorWithCode(.JSONSerializationFailed, failureReason: failureReason)
return .Failure(error)
}
case .Failure(let error):
return .Failure(error)
}
}
return response(responseSerializer: responseSerializer, completionHandler: completionHandler)
}
}
public protocol ResponseCollectionSerializable {
static func collection(response response: NSHTTPURLResponse, representation: AnyObject) -> [Self]
}
extension Alamofire.Request {
public func responseCollection<T: ResponseCollectionSerializable>(completionHandler: Response<[T], NSError> -> Void) -> Self {
let responseSerializer = ResponseSerializer<[T], NSError> { request, response, data, error in
guard error == nil else { return .Failure(error!) }
let JSONSerializer = Request.JSONResponseSerializer(options: .AllowFragments)
let result = JSONSerializer.serializeResponse(request, response, data, error)
switch result {
case .Success(let value):
if let response = response {
return .Success(T.collection(response: response, representation: value))
} else {
let failureReason = "Response collection could not be serialized due to nil response"
let error = Error.errorWithCode(.JSONSerializationFailed, failureReason: failureReason)
return .Failure(error)
}
case .Failure(let error):
return .Failure(error)
}
}
return response(responseSerializer: responseSerializer, completionHandler: completionHandler)
}
}
2) update your model object like this:
final class User: ResponseObjectSerializable, ResponseCollectionSerializable {
let username: String
let name: String
init?(response: NSHTTPURLResponse, representation: AnyObject) {
self.username = response.URL!.lastPathComponent!
self.name = representation.valueForKeyPath("name") as! String
}
static func collection(response response: NSHTTPURLResponse, representation: AnyObject) -> [User] {
var users: [User] = []
if let representation = representation as? [[String: AnyObject]] {
for userRepresentation in representation {
if let user = User(response: response, representation: userRepresentation) {
users.append(user)
}
}
}
return users
}
}
3) then you can use it like that :
Alamofire.request(.GET, "http://example.com/users")
.responseCollection { (response: Response<[User], NSError>) in
debugPrint(response)
}
Source: Generic Response Object Serialization
Useful Link: Alamofire JSON Serialization of Objects and Collections
Since you are using Alamofire to make your requests why don't you give a chance to Hearst-DD ObjectMapper it has an Alamofire extension AlamofireObjectMapper. I think it'll save you time!
I would loop through them then add each user to an array (preferably a property of the VC and not an instance variable) but here is an example.
Alamofire.request(.GET, "YourURL/users")
.responseJSON { response in
if let users = response.result.value {
for user in users {
var swiftUser = User(user: user as! NSDictionary)
//should ideally be a property of the VC
var userArray : [User]
userArray.append(swiftUser)
}
}
}
You could also try EVReflection https://github.com/evermeer/EVReflection
It's even more simple, i.e. to parse JSON (code snippet taken from EVReflection link):
let json:String = "{
\"id\": 24,
\"name\": \"Bob Jefferson\",
\"friends\": [{
\"id\": 29,
\"name\":
\"Jen Jackson\"}]}"
you can use this class:
class User: EVObject {
var id: Int = 0
var name: String = ""
var friends: [User]? = []
}
in this way:
let user = User(json: json)

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