使用AWS开发工具包Go的完整URI从S3下载文件

Question

The examples I've seen for downloading a file from S3 using the AWS SDK for Go are of the form:

downloader := s3manager.NewDownloader(session, /* other args */)

s3object := &s3.GetObjectInput{
    Bucket: aws.String(myBucket),
    Key: aws.String(myKey),
}

bytesDownloaded, err := downloader.Download(myFile, s3object)

That is, one uses the bucket and key to specify the file. But what if I already have the full URI of the file on S3? E.g.:

https://s3.us-west-2.amazonaws.com/myBucket/myKey

Is there a way using the SDK to specify the file to download using the URL directly?

No, the bucket is not public. In the SDK, I'm also setting the access and secret keys (elided from the example code).

Lastly, if it's simply not possible to do what I'm asking via the SDK, that's an acceptable (though not desired) answer.

Answer 1

There is no way to do what you want. The only ways to get a private object are:

1. Use the bucket and key to download the file
2. Generate a presigned URL an do an hhtp.Get on that URL (to generate the presigned URL you need the bucket and key)

If you really want to use the URL I recommend you create a wrapper around s3.GetObjectInput that accepts the URL as an argument, parses it and then create the s3.GetObjectInput object.

Also, I don't know if you could do this it depends on your use case, but if you are storing the URLs somewhere and that's why you want to use them, you can consider storing instead the presigned url with a long expiration time, and then when you want to fetch the object you can just use that URL.