AmazonAmplifyを用いたiOSアプリの画像アップロードについて

前提・実現したいこと

AWSを用いてiOSアプリ(SNSアプリ)のバックエンドを構築中です。
AmazonAmplifyというAPIを用いていて、AmazonS3というストレージにiPhoneから画像をアップロードするプログラムを
AWS公式のGitHubからそのままコピペしたのですが、アップロードできません。

発生している問題・エラーメッセージ

The operation couldn’t be completed.(com.amazonaws.AWSCognitoIdentityErrorDomain error 5.)

該当のソースコード

swift
1import UIKit
2import AWSS3
3import AWSMobileClient
4import AWSAuthUI
5
6class uplaodViewController: UIViewController, UINavigationControllerDelegate {
7    
8    @IBOutlet var progressView: UIProgressView!
9    @IBOutlet var statusLabel: UILabel!
10
11    @objc var completionHandler: AWSS3TransferUtilityUploadCompletionHandlerBlock?
12    @objc var progressBlock: AWSS3TransferUtilityProgressBlock?
13
14    @objc let imagePicker = UIImagePickerController()
15
16    @objc lazy var transferUtility = {
17        AWSS3TransferUtility.default()
18    }()
19
20    override func viewDidLoad() {
21        super.viewDidLoad()
22        
23        super.viewDidLoad()
24               // Do any additional setup after loading the view, typically from a nib.
25               self.progressView.progress = 0.0;
26               self.statusLabel.text = "Ready"
27        self.imagePicker.delegate = self as! UIImagePickerControllerDelegate & UINavigationControllerDelegate
28
29               self.progressBlock = {(task, progress) in
30                   DispatchQueue.main.async(execute: {
31                       if (self.progressView.progress < Float(progress.fractionCompleted)) {
32                           self.progressView.progress = Float(progress.fractionCompleted)
33                       }
34                   })
35    }
36    
37        self.completionHandler = { (task, error) -> Void in
38            DispatchQueue.main.async(execute: {
39                if let error = error {
40                    print("Failed with error: (error)")
41                    self.statusLabel.text = "Failed"
42                }
43                else if(self.progressView.progress != 1.0) {
44                    self.statusLabel.text = "Failed"
45                    NSLog("Error: Failed - Likely due to invalid region / filename")
46                }
47                else{
48                    self.statusLabel.text = "Success"
49                }
50            })
51        }
52    }
53    
54    @IBAction func selectAndUpload(_ sender: UIButton) {
55           imagePicker.allowsEditing = false
56           imagePicker.sourceType = .photoLibrary
57
58           present(imagePicker, animated: true, completion: nil)
59       }
60
61    
62    @objc func uploadImage(with data: Data) {
63          let expression = AWSS3TransferUtilityUploadExpression()
64          expression.progressBlock = progressBlock
65
66          DispatchQueue.main.async(execute: {
67              self.statusLabel.text = ""
68              self.progressView.progress = 0
69          })
70
71          transferUtility.uploadData(
72              data,
73              key: "S3UploadKeyName",
74              contentType: "image/png",
75              expression: expression,
76              completionHandler: completionHandler).continueWith { (task) -> AnyObject? in
77                  if let error = task.error {
78                      print("Error: (error.localizedDescription)")
79
80                      DispatchQueue.main.async {
81                          self.statusLabel.text = "Failed"
82                      }
83                  }
84                
85                if let _ = task.result {
86
87                                   DispatchQueue.main.async {
88                                       self.statusLabel.text = "Uploading..."
89                                       print("Upload Starting!")
90                                   }
91
92                                   // Do something with uploadTask.
93                               }
94
95                               return nil;
96                       }
97}
98
99}
100
101extension uplaodViewController: UIImagePickerControllerDelegate {
102
103    public func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
104// Local variable inserted by Swift 4.2 migrator.
105let info = convertFromUIImagePickerControllerInfoKeyDictionary(info)
106
107        if "public.image" == info[convertFromUIImagePickerControllerInfoKey(UIImagePickerController.InfoKey.mediaType)] as? String {
108            let image: UIImage = info[convertFromUIImagePickerControllerInfoKey(UIImagePickerController.InfoKey.originalImage)] as! UIImage
109            self.uploadImage(with: image.pngData()!)
110        }
111
112
113        dismiss(animated: true, completion: nil)
114    }
115}
116
117// Helper function inserted by Swift 4.2 migrator.
118fileprivate func convertFromUIImagePickerControllerInfoKeyDictionary(_ input: [UIImagePickerController.InfoKey: Any]) -> [String: Any] {
119    return Dictionary(uniqueKeysWithValues: input.map {key, value in (key.rawValue, value)})
120}
121
122// Helper function inserted by Swift 4.2 migrator.
123fileprivate func convertFromUIImagePickerControllerInfoKey(_ input: UIImagePickerController.InfoKey) -> String {
124    return input.rawValue
125}
126