Converting Swift ios Networking to use Alamofire - swift

Question

I got a source code from a github page written in swift and implementing GoogleMaps. I now want to refactor the codes to use Alamofire and SwiftyJSON so that I can improve the code but I got confused because through my learning of swift I used Alamofire and swiftyJSON for every networking process so I am confused currently. the code below
typealias PlacesCompletion = ([GooglePlace]) -> Void
typealias PhotoCompletion = (UIImage?) -> Void
class GoogleDataProvider {
private var photoCache: [String: UIImage] = [:]
private var placesTask: URLSessionDataTask?
private var session: URLSession {
return URLSession.shared
}
let appDelegate = UIApplication.shared.delegate as! AppDelegate
func fetchPlacesNearCoordinate(_ coordinate: CLLocationCoordinate2D, radius: Double, types:[String], completion: #escaping PlacesCompletion) -> Void {
var urlString = "https://maps.googleapis.com/maps/api/place/nearbysearch/json?location=\(coordinate.latitude),\(coordinate.longitude)&radius=\(radius)&rankby=prominence&sensor=true&key=\(appDelegate.APP_ID)"
let typesString = types.count > 0 ? types.joined(separator: "|") : "food"
urlString += "&types=\(typesString)"
urlString = urlString.addingPercentEncoding(withAllowedCharacters: CharacterSet.urlQueryAllowed) ?? urlString
guard let url = URL(string: urlString) else {
completion([])
return
}
if let task = placesTask, task.taskIdentifier > 0 && task.state == .running {
task.cancel()
}
DispatchQueue.main.async {
UIApplication.shared.isNetworkActivityIndicatorVisible = true
}
placesTask = session.dataTask(with: url) { data, response, error in
var placesArray: [GooglePlace] = []
defer {
DispatchQueue.main.async {
UIApplication.shared.isNetworkActivityIndicatorVisible = false
completion(placesArray)
}
}
guard let data = data,
let json = try? JSON(data: data, options: .mutableContainers),
let results = json["results"].arrayObject as? [[String: Any]] else {
return
}
results.forEach {
let place = GooglePlace(dictionary: $0, acceptedTypes: types)
placesArray.append(place)
if let reference = place.photoReference {
self.fetchPhotoFromReference(reference) { image in
place.photo = image
}
}
}
}
placesTask?.resume()
}
func fetchPhotoFromReference(_ reference: String, completion: #escaping PhotoCompletion) -> Void {
if let photo = photoCache[reference] {
completion(photo)
} else {
let urlString = "https://maps.googleapis.com/maps/api/place/photo?maxwidth=200&photoreference=\(reference)&key=\(appDelegate.APP_ID)"
guard let url = URL(string: urlString) else {
completion(nil)
return
}
DispatchQueue.main.async {
UIApplication.shared.isNetworkActivityIndicatorVisible = true
}
session.downloadTask(with: url) { url, response, error in
var downloadedPhoto: UIImage? = nil
defer {
DispatchQueue.main.async {
UIApplication.shared.isNetworkActivityIndicatorVisible = false
completion(downloadedPhoto)
}
}
guard let url = url else {
return
}
guard let imageData = try? Data(contentsOf: url) else {
return
}
downloadedPhoto = UIImage(data: imageData)
self.photoCache[reference] = downloadedPhoto
}
.resume()
}
}
}
any help to refactor the codes to use Alamofire and swiftyJSON would be appreciated.

Answer 1

Both Alamofire and SwiftyJSON have pretty decent instructions, and there are plenty of examples online to look for. However, this would be a decent starting point - you need to replace your session.dataTask and session.downloadTask with Alamofire methods. For example, instead of:
session.downloadTask(with: url) { url, response, error in
var downloadedPhoto: UIImage? = nil
defer {
DispatchQueue.main.async {
UIApplication.shared.isNetworkActivityIndicatorVisible = false
completion(downloadedPhoto)
}
}
guard let url = url else {
return
}
guard let imageData = try? Data(contentsOf: url) else {
return
}
downloadedPhoto = UIImage(data: imageData)
self.photoCache[reference] = downloadedPhoto
}
.resume()
use this skeleton and implement your models and logic:
Alamofire
.request(url)
.responseJSON { dataResponse in
switch dataResponse.result {
case .success:
guard let json = JSON(dataResponse.data) else {
return
}
// Continue parsing
case .failure(let error):
// Handle error
print("\(error)")
}
}