amazon s3 iphone sdk 下载图片

Posted 2023-04-14

【中文标题】amazon s3 iphone sdk 下载图片

【英文标题】：amazon s3 iphone sdk downloading images

【发布时间】：2012-07-31 22:05:55

【问题描述】：

在我的一生中，我无法弄清楚如何在我的 ios 项目中实现亚马逊的 sdk，而且我似乎找不到太多关于我正在尝试做什么的文档......希望你能提供帮助！

我想非常简单地从我的 Amazon S3 帐户下载文件并将它们本地存储在 iPhone 上...我可以通过 http 地址访问图像来做到这一点，但这并不能像我一样保护图像更喜欢。

根据我的阅读，我应该这样做：

AmazonS3Client *s3Client = [[AmazonS3Client alloc] initWithAccessKey:@"mykey" withSecretKey:@"mysecretkey"];

        S3GetObjectRequest *requestedObject = [[S3GetObjectRequest alloc] initWithKey:bucketPath withBucket:@"mybucket"];

        NSLog(@"requestedobject:%@", requestedObject - I get the log here);

        S3GetObjectResponse *getObjectResponse = [s3Client getObject:requestedObject];

        NSLog(@"requestedobject2:%@", getObjectResponse - it crashes before this happens);
        NSData *myData2;
        myData2 = getObjectResponse.body;
        [myData2 writeToFile:bucketPath atomically:YES];

我显然在 getObjectResponse、getObject 代码上做错了，但我不知道正确的语法...任何帮助将不胜感激！

这是日志： 2012-08-02 17:12:33.856 收藏大师版[13176:4e07] 请求对象： 2012-08-02 17:12:34.044 Collection Master Edition[13176:4e07] * 由于未捕获的异常“AmazonServiceException”而终止应用程序，原因：“（null）”

也许我还应该提到我可以使用以下代码获取存储桶列表内容

 S3ListObjectsRequest *listObjectRequest = [[S3ListObjectsRequest alloc] initWithName:@"my bucket"];

        S3ListObjectsResponse *listObjectResponse = [s3Client listObjects:listObjectRequest];

        S3ListObjectsResult *listObjectsResults = listObjectResponse.listObjectsResult;

        for (S3ObjectSummary *objectSummary in listObjectsResults.objectSummaries) 

            NSLog(@"Bucket Contents:%@" ,[objectSummary key]); // This returns the contents of the bucket

        

谢谢！ 扎克

【问题讨论】：

您可能需要重新考虑这样做，而是在您的 iOS 应用程序和 S3 之间添加一个 Web 服务层。否则，您将需要将您的 AWS 凭证放入应用程序本身。因此，如果有人破解了您的应用程序，他们可以完全访问您的 S3 存储（以及该密钥可用的任何其他 Amazon 服务）。

我已经考虑过了，并且已经设置了 TVM Web 服务层...但是我无法通过第一步开始测试 TVM 步骤...我想如果我可以使上述代码正常工作，我可以继续前进（并提出更多问题！）以使 TVM 正常工作-想法？除非你对整个事情有建议！

嘿，你解决了这个问题吗？我在这里面临同样的问题。

对于遇到同样问题的任何人，这篇文章对我有帮助：***.com/questions/18318487/…

【参考方案1】：

从我在这里看到的情况来看，您可能会遇到两个问题之一。我第一次开始使用 AWS 时遇到了类似的问题。首先确保您的存储桶名称全部为小写字母。您应该通过将其放入 @try - @catch 块并记录错误来检查为什么会发生这种情况，这在解决您的问题时提供了非常详细的信息。

    -(UIImage *)getImageFromS3      


    @try
    AmazonS3Client *_s3Client = [[AmazonS3Client alloc]initWithAccessKey:ACCESS_KEY withSecretKey:SECRET_KEY];      

    S3GetObjectRequest *getObjectRequest = [[S3GetObjectRequest alloc]initWithKey:imageKey withBucket:pictureBucket];

  S3GetObjectResponse *response = [_s3Client getObject:getObjectRequest];

    if (response.error == nil)
    
        if (response.body != nil)
        
        UIImage *someImage = [UIImage imageWithData:reponse.body];
    return someImage;
        
        else
            NSLog(@"There was no value in the response body");
            return nil;
             
    
    else if (response.error != nil)
    
        NSLog(@"There was an error in the response while getting image: %@",response.error.description);
    


    @catch (NSException *exception) 
    NSLog(@"There was an exception when connecting to s3: %@",exception.description);


 

【参考方案2】：

问题可能是与您的密钥对关联的权限。我的建议是去你的IAM on your Management Console 并创建一个具有你想要的适当 S3 权限的新组，在这种情况下几乎所有这些权限，除了一些你不需要的更多管理的东西（所以主要只是 POST，GET权限）。然后在该组中创建一个用户并使用该密钥对进行测试。这可能会让事情变得清晰，因为这是我认为对我有用的过程。貌似列表权限比较低，但是POST和GET需要不同的权限。

【参考方案3】：

可能是允许的，但可能会帮助某些人。这是在amazone-s3中上传图片的代码

constant.h
#import <Foundation/Foundation.h>
#define SECRET_KEY             @"your secret kry"
#define ACCESS_KEY_ID          @"your access id"

#define PICTURE_BUCKET @"桶名" #define PICTURE_NAME @"任何单词" #define CREDENTIALS_ERROR_TITLE @"缺少凭据" #define CREDENTIALS_ERROR_MESSAGE @"AWS 凭证配置不正确。请查看 README 文件。"

@interface 常量：NSObject

+(NSString *)pictureBucket;

@结束

在常量.m中

#import "Constant.h"

@implementation 常量 +(NSString *)图片桶 return [[NSString stringWithFormat:@"%@-%@", PICTURE_BUCKET, ACCESS_KEY_ID] lowercaseString];

@end

在 UploadViewController.h 中

  typedef enum 
  GrandCentralDispatch,
  Delegate,
  BackgroundThread
   UploadType;

  @interface UploadPhotoViewController :  UIViewController<UIImagePickerControllerDelegate,UINavigationControllerDelegate,UINavigationControllerDelegate, AmazonServiceRequestDelegate>
 
UploadType _uploadType;
 

 @property (strong, nonatomic) IBOutlet UIButton *buttonSelectPhoto;
  @property (nonatomic, retain) AmazonS3Client *s3;

在 UploadViewController.m 中

      #import "UploadPhotoViewController.h"
       #import <AWSRuntime/AWSRuntime.h>
      #import "Constant.h"

       @interface UploadPhotoViewController ()

        @end

         @implementation UploadPhotoViewController

     - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
        
     self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) 
    // Custom initialization
      
       return self;
     

       - (void)viewDidLoad
      
     [super viewDidLoad];
// Do any additional setup after loading the view from its nib.

     #ifdef DEBUG
     [AmazonLogger verboseLogging];
   #else
      [AmazonLogger turnLoggingOff];
   #endif

     [AmazonErrorHandler shouldNotThrowExceptions];

      if(![ACCESS_KEY_ID isEqualToString:@"CHANGE ME"]
          && self.s3 == nil)
       
    // Initial the S3 Client.
    //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    // This sample App is for demonstration purposes only.
    // It is not secure to embed your credentials into source code.
    // DO NOT EMBED YOUR CREDENTIALS IN PRODUCTION APPS.
    // We offer two solutions for getting credentials to your mobile App.
    // Please read the following article to learn about Token Vending Machine:
    // * http://aws.amazon.com/articles/Mobile/4611615499399490
    // Or consider using web identity federation:
    // * http://aws.amazon.com/articles/Mobile/4617974389850313
    //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    self.s3 = [[AmazonS3Client alloc] initWithAccessKey:ACCESS_KEY_ID withSecretKey:SECRET_KEY] ;
    self.s3.endpoint = [AmazonEndpoints s3Endpoint:US_WEST_2];

    // Create the picture bucket.
    S3CreateBucketRequest *createBucketRequest = [[S3CreateBucketRequest alloc] initWithName:[Constant pictureBucket] andRegion:[S3Region USWest2]];
    S3CreateBucketResponse *createBucketResponse = [self.s3 createBucket:createBucketRequest];
    if(createBucketResponse.error != nil)
    
        NSLog(@"Error: %@", createBucketResponse.error);
    


  
   -(void)viewDidAppear:(BOOL)animated
 
[super viewDidAppear:animated];

if ([ACCESS_KEY_ID isEqualToString:@"CHANGE ME"])

    [self showAlertMessage:CREDENTIALS_ERROR_MESSAGE withTitle:CREDENTIALS_ERROR_TITLE];

- (void)showAlertMessage:(NSString *)message withTitle:(NSString *)title UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:title 消息：消息 代表：无 取消按钮标题：@“确定” 其他按钮标题：无]； alertView.delegate=self; [警报视图显示]； - (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex

dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
dispatch_async(queue, ^

    // Set the content type so that the browser will treat the URL as an image.
    S3ResponseHeaderOverrides *override = [[S3ResponseHeaderOverrides alloc] init];
    override.contentType = @"image/jpeg";

    // Request a pre-signed URL to picture that has been uplaoded.
    S3GetPreSignedURLRequest *gpsur = [[S3GetPreSignedURLRequest alloc] init];
    gpsur.key                     = PICTURE_NAME;
    gpsur.bucket                  = [Constant pictureBucket];
    gpsur.expires                 = [NSDate dateWithTimeIntervalSinceNow:(NSTimeInterval) 3600]; // Added an hour's worth of seconds to the current time.
    gpsur.responseHeaderOverrides = override;

    // Get the URL
    NSError *error = nil;
    NSURL *url = [self.s3 getPreSignedURL:gpsur error:&error];

    if(url == nil)
    
        if(error != nil)
        
            dispatch_async(dispatch_get_main_queue(), ^

                NSLog(@"Error: %@", error);
                [self showAlertMessage:[error.userInfo objectForKey:@"message"] withTitle:@"Browser Error"];
            );
        
    
    else
    
        /*dispatch_async(dispatch_get_main_queue(), ^
            // Display the URL in Safari
            [[UIApplication sharedApplication] openURL:url];

        );*/
    NSLog(@"url is %@",url);

);

 

   - (void)didReceiveMemoryWarning
   
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
  

   - (IBAction)buttonTakePhoto:(id)sender
   
UIImagePickerController *picker = [[UIImagePickerController alloc] init];

picker.delegate = self;

picker.allowsEditing = YES;

picker.sourceType = UIImagePickerControllerSourceTypeCamera;



[self presentViewController:picker animated:YES completion:NULL];
  

   - (IBAction)buttonSelectPhoto:(id)sender
   
 [self showImagePicker:Delegate];
 

    - (void)showImagePicker:(UploadType)uploadType

UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init] ;
imagePicker.delegate = self;

_uploadType = uploadType;

[self presentViewController:imagePicker animated:YES completion:NULL];
   


  - (void)processDelegateUpload:(NSData *)imageData
 
// Upload image data.  Remember to set the content type.
S3PutObjectRequest *por = [[S3PutObjectRequest alloc] initWithKey:PICTURE_NAME
                                                          inBucket:[Constant pictureBucket]];
por.contentType = @"image/jpeg";
por.data = imageData;
por.delegate = self;

// Put the image data into the specified s3 bucket and object.
[self.s3 putObject:por];
 

     -(void)request:(AmazonServiceRequest *)request didCompleteWithResponse:(AmazonServiceResponse *)response
  
[self showAlertMessage:@"The image was successfully uploaded." withTitle:@"Upload Completed"];

[[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:NO];
  

 -(void)request:(AmazonServiceRequest *)request didFailWithError:(NSError *)error
  
NSLog(@"Error: %@", error);
[self showAlertMessage:error.description withTitle:@"Upload Error"];

[[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:NO];
  

   #pragma mark - UIImagePickerControllerDelegate methods

       -(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
    
// Get the selected image.
UIImage *image = [info objectForKey:UIImagePickerControllerOriginalImage];

// Convert the image to JPEG data.
NSData *imageData = UIImageJPEGRepresentation(image, 1.0);


if(_uploadType == Delegate)

    [self processDelegateUpload:imageData];


[[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:YES];

[picker dismissViewControllerAnimated:YES completion:NULL];
   

   -(void)imagePickerControllerDidCancel:(UIImagePickerController *)picker
  
[picker dismissViewControllerAnimated:YES completion:NULL];
   

     - (IBAction)buttonBack:(id)sender
     
[self.navigationController popViewControllerAnimated:YES];
   

   @end