删除Amazon S3 Java中的文件，目录和存储桶 [英] Delete files, directories and buckets in amazon s3 java

问题描述

我想知道如何做到这一点.我查看了sdk文档并提供了一些示例，但对语法的一般用法感到困惑.

I'm wondering how to do this. I looked at the sdk documentation and have some examples, but am confused how the syntax generally goes.

如果要删除文件，我假设我使用 deleteObject(path，key).但是，钥匙"是什么?

If I want to delete a file, I assume I use deleteObject(path, key). However, what is the "key"?

还如何删除目录?我似乎找不到执行此操作的方法.

Also how do you delete a directory? I can't seem to find a method for doing that.

推荐答案

S3中的键"类似于文件路径:

A "key" in S3 is similar to a file path:

http://bucket.s3.amazonaws.com/some/path/to/use

...位于名为 bucket 的存储桶中，其密钥为 some/path/to/use .

... is in a bucket named bucket and has a key of some/path/to/use.

它实际上不是路径，因为没有文件夹.S3密钥只是一个大目录(整个存储桶)中文件的文件名.S3密钥可以包含/，但是除非您设置

It's not actually a path though, because there are no folders. The S3 key is just the file name for a file in one big directory (the entire bucket). S3 keys can contain /, but it has no special meaning unless you set the delimiter argument with listing a bucket.

换句话说，拥有一个名为 some/object 的对象不会告诉您有关该对象 some 的任何信息(它可能存在或可能不存在-这两个对象无关).

In other words, having an object named some/object doesn't tell you anything about the object some (it might or might not exist -- the two objects are not related).

但是，您可以请求具有特定前缀的密钥，因此我可以说给我所有以 some/path/to/开头的密钥，它将返回 some/path/to/use .它看起来像列出目录"，但实际上只是在询问以特定字符串开头的文件.

However, you can request keys with a specific prefix, so I could say "give me all keys starting with some/path/to/ and it will return some/path/to/use. It looks like "listing a directory", but it's really just asking for files that start with a specific string of characters.

我可以很容易地这样命名:

I could just as easily name things like this:

somepathtousea
somepathtouseb

并说给我以 somepathtouse 开头的所有内容"(它会说 somepathtousea 和 somepathtouseb ).

And say "give me everything starting with somepathtouse" (and it would say somepathtousea and somepathtouseb).

注意:S3 URL以几种形式:

Note: S3 URL's come in several forms:

http://s3.amazonaws.com/bucket/key
http://bucket.s3.amazonaws.com/key
http://bucket/key (where bucket is a DNS CNAME record pointing to bucket.s3.amazonaws.com)

我查看了 JavaDocs ，这是我看到的功能签名(对于 AmazonS3Client ):

I looked at the JavaDocs and this is the function signature I see (for AmazonS3Client):

public void deleteObject(java.lang.String bucketName,
                         java.lang.String key)
                  throws AmazonClientException,
                         AmazonServiceException

再次

文件夹确实存在，它们是零长度的对象，其内容类型为 application/x-directory ，并且键的结尾为/:

Folders do kind-of exist now, as zero-length objects with a content-type of application/x-directory and a key ending in /:

$ AWS_PROFILE=prod aws s3api head-object --bucket example-bucket --key example-directory/
{
    "AcceptRanges": "bytes",
    "LastModified": "Mon, 29 Apr 2019 14:59:36 GMT",
    "ContentLength": 0,
    "ETag": "\"d41d8cd98f00b204e9800998ecf8427e\"",
    "ContentType": "application/x-directory",
    "ServerSideEncryption": "AES256",
    "Metadata": {}
}

这仍然只是惯例，没有什么可以阻止您以/结尾的文件或不存在的文件夹"中的文件.

This is still just convention and there's nothing stopping you from having files ending / or files inside of "folders" that don't exist.

这篇关于删除Amazon S3 Java中的文件，目录和存储桶的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！