ruby - 检查 s3 存储桶中是否存在文件夹

Question

如何使用 Ruby on Rails 检查我的 s3 存储桶中是否存在某个文件夹？

我正在使用 AWS:S3 官方 gem初始化全局连接后

AWS::S3::Base.establish_connection!(:access_key_id => 'my_key_id', :secret_access_key => ‘my_secret’) 

我的桶名为:myfirstbucket

内部文件夹名为:my_folder

my_folder 中的文件名为:my_pic.jpg

当我尝试检查 my_pic.jpg 是否存在时，它工作得很好

s3object.exists? “/my_folder/my_pic.jpg” , “myfirstbucket”
=>  True

如何只检查文件夹是否存在？

s3object = AWS::S3::S3Object
s3object.exists? “/my_folder/” , “myfirstbucket”
=>  False

Answer 1

使用Bucket#objects:

bucket.objects({prefix: 'my/folder/'}).limit(1).any?

Returns a Collection of ObjectSummary resources. No API requests are made until you call an enumerable method on the collection. Client#list_objects will be called multiple times until every ObjectSummary has been yielded.

—http://docs.aws.amazon.com/sdkforruby/api/Aws/S3/Bucket.html#objects-instance_method