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假设我有一个名为bucketSample.

而且我有不同的文件夹,例如abc,defxyz.

现在我hij_在上述所有文件夹中有多个带有前缀的文件。

我想下载所有带有前缀的文件hij_。(例如,,,hij_qwe.txthij_rty.pdf

我经历了各种方式,但GetObject我必须提供特定的对象名称,而且我只知道前缀。

并且使用 TransferManager 我可以下载文件夹的所有文件,abc但不能下载具有特定前缀的文件。

那么有什么方法可以让我只下载所有带前缀的文件hij_吗?

4

2 回答 2

2
public void getFiles(final Set<String> bucketName, final Set<String> keys, final Set<String> prefixes) {
    try {
        ObjectListing objectListing = s3Client.listObjects(bucketName); //lists all the objects in the bucket
        while (true) {
            for (Iterator<?> iterator = objectListing.getObjectSummaries().iterator();
                 iterator.hasNext(); ) {
                S3ObjectSummary summary = (S3ObjectSummary) iterator.next();
                for (String key : keys) {
                    for (String prefix : prefixes)
                        if (summary.getKey().startsWith(key + "/" prefix)) {
                            //HERE YOU CAN GET THE FULL KEY NAME AND HENCE DOWNLOAD IT IN NEW FILE USING THE TRANFER MANAGER
                        }
                    }
                }
            }
            if (objectListing.isTruncated()) {
                objectListing = s3Client.listNextBatchOfObjects(objectListing);
            } else {
                break;
            }
        }
    } catch (AmazonServiceException e) { }
}

在此处阅读 AWS 目录结构:AWS S3 如何存储文件?(目录结构)

因此,对于您的用例,键 + “/” + 前缀充当存储在 S3 存储桶中的对象的前缀。通过比较前缀将 S3 Bucket 中的所有对象,可以得到完整的键名。

于 2018-06-05T14:08:40.147 回答
0

使用 python,您可以使用 boto3 库,我发现它对于解决类似情况非常有用。

示例代码:

import boto3
import os

KEY = ''
SECRET = ''
download_folder = os.path.join(os.path.expanduser('~'), 'Downloads')
bucket = 'bucketSample'
folders = ['abc', 'def', 'xyz']
prefixes = ['hij_']

try:
    # Needed for the pagination method in order to get objects with certain prefixes instead of iterating over all objects, you should get the aws_access_key_id and aws_secret_access_key for your bucket if available
    s3 = boto3.resource(
        's3',
        aws_access_key_id=KEY,
        aws_secret_access_key=SECRET)

    # Needed for the download method, you should get the aws_access_key_id and aws_secret_access_key for your bucket if available
    client = boto3.client(
        's3',
        aws_access_key_id=KEY,
        aws_secret_access_key=SECRET)

    # Get paginated objects
    paginator = client.get_paginator('list_objects')

    for folder in folders:
        for file_prefix in prefixes:
            prefix = folder + file_prefix
            page_iterator = paginator.paginate(Bucket=bucket, Prefix=prefix)

            if page_iterator:
                for page in page_iterator:
                    if 'Contents' in page:
                        for content in page['Contents']:
                            file_path = os.path.join(download_folder, content['Key'])
                            s3.meta.client.download_file(bucket, str(content['Key']), file_path)
except:
    print('An error occurred')
于 2019-06-10T13:14:19.437 回答