S3 - 上传 - 如何生成预签名的 url，让每个人都能读取 object？

Question

I'm trying to provide a pre-signed url that, once the image is uploaded, grants the group Everyone read access to the uplodaded image. So far, I'm generating the pre-signed url with the following steps:

    val req = GeneratePresignedUrlRequest(params.s3Bucket,"$uuid.jpg",HttpMethod.PUT)
    req.expiration = expiration
    req.addRequestParameter("x-amz-acl","public-read")
    req.addRequestParameter("ContentType","image/jpeg")
    val url: URL = s3Client.generatePresignedUrl(req)

But the image, once I check in S3, does not have the expected read access.

Answer 1

The HTTP client that performs the upload needs to include the x-amz-acl: public-read header.

In your example, you're generating a request that includes that header. But, then you're generating a presigned URL from that request.

URLs don't contain HTTP headers, so whatever HTTP client you're using to perform the actual upload is not sending setting the header when it sends the request to the generated URL.

Answer 2

This simple answer is working for me.

val url = getS3Connection().,,generatePresignedUrl( "bucketname". "key", Date(Date().time + 1000 * 60 * 300) )