Feature: ability to generate virtually-hosted/cnamed urls for a given bucket

[jbr]

I have a us standard bucket with a bucket name that is also a cnamed fqdn like storage.mysite.com and would like any generated urls to use that cname / virtual host. By generated urls, I mean any url that might be public-facing, not necessarily urls that the gem uses internally to speak to s3. In my use case, this would include Aws::S3::Object#public_url and Aws::S3::Object#presigned_url, but there may be more methods like this. It would be ideal to set this on creation / access of the bucket, like:

BUCKET = Aws::S3::Resource.new(region, creds).
  bucket('storage.mysite.com', virtual_host: true)

It might be useful to someone if that could also be overridden per object method, so BUCKET.object('not-cnamed').public_url(virtual_host: false) would revert to default behavior, or so

Aws::S3::Resource.new(region, creds).
  bucket('storage.mysite.com').
  object('cnamed').
  public_url(virtual_host: true)

would result in something like http://storage.mysite.com/cnamed

This could also raise a useful exception if the bucket isn't us-standard and the user is trying to set virtual_host: true

I understand that this would be mutually exclusive with secure: true and would expect the gem to raise if I tried to specify both of them.

Thank you!

[trevorrowe]

Thanks for posting the feature request. I'm out traveling for the week, but lets continue the conversation early next week.

[bilus]

@trevorrowe Have you been able to look into this? We badly need support for presigned urls using CNAMEd buckets. Unlike @jbr, we host the files outside us-standard so +1 to a solution that somehow takes that into account before we close this door and make it difficult to add this functionality in the future.

If there's any way I can help move it forward, please let me know.

[trevorrowe]

@bilus I was previously looking at this. I have a local proof of concept branch which lacks tests. I got to the point where I needed a live bucket in S3 with a cname and I lacked one at the time. I need to circle back on this, but haven't had the opportunity too.

[bilus]

Actually, I've been able to generate the urls using the code similar to this:

  bucket_name = "some-bucket.example.com"
  s3 = Aws::S3::Client.new(endpoint: "http://example.com", region: "eu-central-1")
  bucket = Aws::S3::Bucket.new("some-bucket", client: s3)
  object = bucket.object("some-key")
  object.presigned_url(:get, expires_in: 24 * 3600, secure: false)

This probably gives a better idea of what goes where (and should probably work but it's untested):

def generate_presigned_url(region, domain, bucket_basename, key, expire_after)
  bucket_name = "#{bucket_basename}.#{domain}"   
  s3 = Aws::S3::Client.new(endpoint: "http://#{domain}", region: region)   
  bucket = Aws::S3::Bucket.new(bucket_basename, client: s3)
  object = bucket.object(key)
  object.presigned_url(:get, expires_in: expire_after, secure: false)
end

As this based on stepping through the code with a debugger and not docs, I'm leaving stuff that can probably be omitted (e.g. region).

The secure: false bit is important because of lack of security certificates for some-bucket.example.com.