如何检查 Amazon S3 存储桶中的文件夹是否为空？ - boto3 python

Question

我有一个 Amazon S3 存储桶

my-bucket

和文件夹

my-folder

。

我希望我的脚本根据带有

my-folder

的文件是否存在（或不存在）来执行不同的结果。因此，我想检查

my-folder

是否为空并且不包含任何文件。

我该怎么做？

不幸的是，我尝试搜索文档和其他 Stack Overflow 帖子，但似乎找不到类似的内容。

Answer 1

您可以计算前缀中的对象数量：

import boto3

BUCKET_NAME = 'bucket'
FOLDER_NAME = 'my-folder/'

s3_resource = boto3.resource('s3')

bucket = s3_resource.Bucket(BUCKET_NAME)

count = bucket.objects.filter(Prefix=FOLDER_NAME)

print(len(list(count)))

Answer 2

由于@john Rotenstein 代码不适用于嵌套文件夹，所以我编写了这段代码，它的作用就像一个魅力。

def check_files_in_s3_folder(bucket_name, folder_name):
    """
    Checks if there is any file in a specified folder within an S3 bucket.

    Parameters:
    - bucket_name: The name of the S3 bucket.
    - folder_name: The name of the folder inside the bucket.

    Returns:
    - True if the folder contains files, False otherwise.
    """
    # Ensure the folder name ends with a slash
    if not folder_name.endswith('/'):
        folder_name += '/'

    # Initialize a session using Amazon S3
    s3 = boto3.client('s3')

    try:
        # List objects within the specified folder
        response = s3.list_objects_v2(Bucket=bucket_name, Prefix=folder_name, Delimiter='/')

        # Check if the folder actually contains files directly
        if 'Contents' in response:
            # Ensure there's at least one object directly in the folder
            for obj in response['Contents']:
                if obj['Key'] != folder_name:  # Exclude the folder itself if listed
                    return True
        return False
    except Exception as e:
        print(f"An error occurred: {e}")
        return False