userInfo Network call

GHFollowers/Managers/NetworkManager.swift

@@ -19,6 +19,15 @@ class NetworkManager {
     private init() {}
 
 
+    // MARK: @escaping closure explenation
+    /*
+        Closures can be escaping or non escaping. If a closuse is escaping can 'outlive' the function that is declared in
+        It is used for asychronus operations (basically like a promise in JavaScript)
+        When we use an escaping closure we need to deal also with memory management (that why we use [weak self] on the return of the promise
+     */
+
+
+    // MARK: Followers Call
     func getFollowers(for username: String, page: Int, completed: @escaping(Result<[Follower], GFError>) -> Void) {
         // set endpoint
         let endpoint = baseUrl + "/users/\(username)/followers?per_page=100&page=\(page)"
@@ -80,9 +89,73 @@ class NetworkManager {
 
         // start network call
         task.resume()
+    }
+
+
+
+
+    // MARK: User Call
+    func getUserInfo(for username: String, completed: @escaping(Result<User, GFError>) -> Void) {
+        // set endpoint
+        let endpoint = baseUrl + "/users/\(username)"
 
+        // make sure endpoint is a valid string
+        guard let url = URL(string: endpoint) else {
+            // if not we need to pass an error message to the callback (completed)
+            // so our ViewController that calls that function can print the custom alert
+            // because we should print Views only from main thread
+
+            // call the callback and pass the error
+            completed(.failure(.invalidUsername))
+            return
+        }
 
 
+        // URL Session data task (call api)
+        let task = URLSession.shared.dataTask(with: url) { data, response, error in
+
+            // if error exists and its not nil
+            // this error will return if the network call wasn't even made
+            if let _ = error {
+                completed(.failure(.unableToComplete))
+                return
+            }
+
+            // if response exists and is not nil and if status code is 200(OK)
+            // cast it as a HTTPURLResponse adn save in the variable
+            // ELSE call completed with the error string
+            guard let response = response as? HTTPURLResponse, response.statusCode == 200 else {
+                completed(.failure(.invalidResponse))
+                return
+            }
+
+            // check if the data response is good and save in the variable data
+            // else call completed
+            guard let data = data else {
+                completed(.failure(.invalidData))
+                return
+            }
+
+            // Decode JSON file and place it in model
+            do {
+                let decoder = JSONDecoder()
+                // convert keys from snake_case to camelCase
+                decoder.keyDecodingStrategy = .convertFromSnakeCase
+                // array we want to create          its type        from the data constant from above
+                let user = try decoder.decode(User.self, from: data)
+                // if all ok call the completed callback, passing the array and nil for error
+                completed(.success(user))
+
+            } catch {
+                // if the decoder above throws
+                completed(.failure(.invalidData))
+            }
+
+
+        }
+
+        // start network call
+        task.resume()
     }
 
 }

GHFollowers/Model/User.swift

@@ -9,17 +9,17 @@
 import Foundation
 
 
-struct User {
+struct User: Codable {
 
-    var login: String
-    var avatarUrl: String
+    let login: String
+    let avatarUrl: String
     var name: String?
     var location: String?
     var bio: String?
-    var publicRepos: Int
-    var publicGists: Int
-    var htmlUrl: String
-    var following: Int
-    var followers: Int
-    var createdAt: String
+    let publicRepos: Int
+    let publicGists: Int
+    let htmlUrl: String
+    let following: Int
+    let followers: Int
+    let createdAt: String
 }

GHFollowers/Screens/UserInfoVC.swift

@@ -21,7 +21,21 @@ class UserInfoVC: UIViewController {
         let doneButton = UIBarButtonItem(barButtonSystemItem: .done, target: self, action: #selector(dismissVC))
         // add button to navigation bar
         navigationItem.rightBarButtonItem = doneButton
-        print(username!)
+
+
+        NetworkManager.shared.getUserInfo(for: username) { [weak self] result in
+            guard let self = self else {return}
+
+            switch result {
+            case .success(let user):
+                print(user)
+            case .failure(let error):
+                self.presentGFAlertOnMainThread(title: "Something went wrong", message: error.rawValue, buttonTitle: "Ok")
+            }
+
+
+        }
+
     }
 
     @objc func dismissVC() {