MVC Sample



First at all. Where is the data came from?

I’m loading the data from the local json file – Albums.json.

Data models

struct Album {

  let albumId: Int
  let albumName: String
  let artistName: String
  let artworkUrl: URL?
  let tracks: [Track]

  init(albumId: Int, albumName: String, artistName: String, artworkUrl: URL?, tracks: [Track]) {
    self.albumId = albumId
    self.albumName = albumName
    self.artistName = artistName
    self.artworkUrl = artworkUrl
    self.tracks = tracks


struct AlbumsResponse: Decodable {

  let resultCount: UInt
  let results: [AlbumResponse]


struct AlbumResponse: Decodable {

  let albumId: Int
  let albumName: String
  let artistName: String
  let artworkUrl: String
  let tracks: [TrackResponse]


struct Track {

  let trackId: Int
  let trackName: String
  let releaseDate: String
  let releaseYear: String
  let previewUrl: URL?
  let primaryGenreName: String
  let trackViewUrl: URL?
  let trackDuration: String
  let trackPrice: String?

  init(trackId: Int, trackName: String, releaseDate: String, releaseYear: String, previewUrl: URL?, primaryGenreName: String, trackViewUrl: URL?, trackDuration: String, trackPrice: String?) {
    self.trackId = trackId
    self.trackName = trackName
    self.releaseDate = releaseDate
    self.releaseYear = releaseYear
    self.previewUrl = previewUrl
    self.primaryGenreName = primaryGenreName
    self.trackViewUrl = trackViewUrl
    self.trackDuration = trackDuration
    self.trackPrice = trackPrice


struct TrackResponse: Decodable {

  let trackId: Int
  let trackName: String
  let trackViewUrl: String
  let previewUrl: String?
  let releaseDate: String
  let primaryGenreName: String
  let trackPrice: Float?
  let currency: String
  let trackTimeMillis: Int?


I’m using a Swift Standard Library decodable functionality in order to manage a type that can decode itself from an external representation.

Reference: Apple documentation



Used to process the albums from the json data.


Used to process the tracks from the json data.


Used to process the songs.

Unit Test


Test getting the extra large image (200 x 200).


Test fetching the albums and tracks from AlbumsTest.json. We can update the content of the json file as per model structure for test.


Test getting the minutes:seconds formatted string from the milliseconds.

What should be implemented in the demo?

  • Load the albums and tracks from REST API: I loaded the albums and tracks from the local file – Albums.json . The best option should be to fetch the data from REST API.

What’s left in the demo?

  • Update the managers: I implemented the managers using singletons. The best option should be to remove the singletons in order to use dependency injections (to improve the testing).
  • Manage the UISlider: For this version the UISlider in track detail page has the user interaction enable in “false”. It would be nice to allow the user to manage the slider.

Third-Party Libraries

I added the third-party libraries via Swift Package Manager

  • Kingfisher (6.3.1): A pure-Swift library for downloading and caching images from the web.


View Github