AWS S3：列出特定S3文件夹中的对象？

Question

我正在使用AWS IOS SDK从S3下载文件，并且无法在S3存储桶的特定文件夹中列出对象。 我可以使用listObjectsInBucket方法列出整个存储桶的所有文件，但我只需要列出存储桶中特定文件夹中的文件。

所以我尝试使用listObjects方法并指定存储桶名称和前缀 （在S3上指示文件夹名称）。

但是以下代码不起作用。

S3ListObjectsRequest *lor = [S3ListObjectsRequest alloc];
lor.bucket = @"bucketName";
lor.prefix = @"/folderName1/foldername2";

S3ListObjectsResponse *ListObjectResponse = [self.s3 listObjects:lor];

Answer 1

只是简单地不要把“/”放在folderName1的前面，事情就会解决。

迅速：

let listObjectsRequest = AWSS3ListObjectsRequest()
    listObjectsRequest.bucket = "(your bucket name)"
    listObjectsRequest.prefix = "(subfolder1)/(subfolder2)" 
    s3.listObjects(listObjectsRequest).continueWithBlock { (task) -> AnyObject! in .......

Objective-C的：

S3ListObjectsRequest *lor = [S3ListObjectsRequest alloc];
lor.bucket = @"bucketName";
lor.prefix = @"folderName1/foldername2"; 

S3ListObjectsResponse *ListObjectResponse = [self.s3 listObjects:lor];

Answer 2

AWSS3ListObjectsRequest *listObjectsRequest = [AWSS3ListObjectsRequest new];
    listObjectsRequest.bucket = @"YourBucketName";

[[s3 listObjects:listObjectsRequest] continueWithBlock:^id(AWSTask *task)
 {
    if (task.error)
    {
        [MBProgressHUD hideAllHUDsForView:self.view animated:YES];
        NSLog(@"listObjects failed: [%@]", task.error);
    }
    else
    {
        AWSS3ListObjectsOutput *listObjectsOutput = task.result;

        for (AWSS3Object *s3Object in listObjectsOutput.contents)
        {
            downloadingFilePath = [[NSTemporaryDirectory() stringByAppendingPathComponent:@"download"] stringByAppendingPathComponent:s3Object.key];

            NSURL *downloadingFileURL = [NSURL fileURLWithPath:downloadingFilePath];

            AWSS3TransferManagerDownloadRequest *downloadRequest = [AWSS3TransferManagerDownloadRequest new];
            downloadRequest.bucket = @"YourBucketName";
            downloadRequest.key = s3Object.key;
            downloadRequest.downloadingFileURL = downloadingFileURL;

            AWSS3TransferManager *transferManager = [AWSS3TransferManager defaultS3TransferManager];
            [[transferManager download:downloadRequest] continueWithBlock:^id(AWSTask *task)
             {
                 if ([task.error.domain isEqualToString:AWSS3TransferManagerErrorDomain]
                     && task.error.code == AWSS3TransferManagerErrorPaused)
                 {
                     NSLog(@"Download paused.");
                 }
                 else if (task.error)
                 {
                     NSLog(@"Upload failed: [%@]", task.error);
                 }
                 else
                 {
                     dispatch_async(dispatch_get_main_queue(), ^
                                    {
                                        //_imgNew.image = [ UIImage imageNamed:[NSString stringWithFormat:@"%@",downloadRequest.downloadingFileURL]];
                                    });
                 }
                 return nil;
             }];
        }

        dispatch_async(dispatch_get_main_queue(), ^{
            [self setUpScrollViews];
            NSLog(@"Set images called");
            [MBProgressHUD hideAllHUDsForView:self.view animated:YES];
        });
    }
    return nil;
}];