Java 如何通过 SDK 设置 S3 对象的内容类型？
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How to set the content type of an S3 object via the SDK?
提问by Click Upvote
I'm trying to use AWS Api to set the content type of multiple objects and to add a 'content-encoding: gzip' header to them. Here's my code for doing that:
我正在尝试使用 AWS Api 设置多个对象的内容类型并向它们添加“内容编码：gzip”标头。这是我这样做的代码：
for (S3ObjectSummary summary : objs.getObjectSummaries() )
{
String key = summary.getKey();
if (! key.endsWith(".gz"))
continue;
ObjectMetadata metadata = new ObjectMetadata();
metadata.addUserMetadata("Content-Encoding", "gzip");
metadata.addUserMetadata("Content-Type", "application/x-gzip");
final CopyObjectRequest request = new CopyObjectRequest(bucket, key, bucket, key)
.withSourceBucketName( bucket )
.withSourceKey(key)
.withNewObjectMetadata(metadata);
s3.copyObject(request);
}
When I run this however, the following is the result:
但是，当我运行它时，结果如下：
As you can see, the prefix x-amz-metawas added to my custom headers, and they were lower cased. And the content-typeheader was ignored, instead it put www/form-encodedas the header.
如您所见，前缀x-amz-meta已添加到我的自定义标题中，并且它们是小写的。并且content-type标题被忽略，而是www/form-encoded作为标题放置。
What can I do it to cause it to accept my header values?
我该怎么做才能让它接受我的标头值？
采纳答案by Click Upvote
Found the problem. ObjectMetadatarequires the content-type / encoding to be set explicitly rather than via addUserMetadata(). Changing the following:
发现问题了。ObjectMetadata需要显式设置内容类型/编码，而不是通过addUserMetadata()。更改以下内容：
metadata.addUserMetadata("Content-Encoding", "gzip");
metadata.addUserMetadata("Content-Type", "application/x-gzip");
to:
到：
metadata.setContentEncoding("gzip");
metadata.setContentType("application/x-gzip");
fixed this.
修复了这个。
