S3. Update virtual hosting URI pattern

[iRevive]

Versions used

Alpakka version: 2.0.0, 1.1.2

Expected Behavior

I'm trying to access a bucket in the af-south-1 region.
Expected URI pattern: https://{bucketname}.s3.{Region}.amazonaws.com.

The current pattern works for certain regions, but unfortunately it does not work for the new one (af-south-1).

Official docs:

In practice, Amazon S3 interprets Host as meaning that most buckets 
are automatically accessible for limited types of requests at 
https://bucketname.s3.Region.amazonaws.com.

Some older Amazon S3 Regions support endpoints that contains 
a dash between S3 and the Region (for example, S3‐us-west-2), 
instead of a dot (for example, S3.us-west-2).

Source: https://docs.aws.amazon.com/AmazonS3/latest/dev/VirtualHosting.html.

Actual Behavior

Alpakka uses the following pattern: https://{bucketname}.s3-{Region}.amazonaws.com.
Result URI: https://my-bucket.s3-af-south-1.amazonaws.com.

Exception:

Caused by: akka.stream.StreamTcpException: 
Tcp command [Connect(my-bucket.s3-af-south-1.amazonaws.com:443,None,List(),Some(10 seconds),true)] 
failed because of java.net.UnknownHostException: my-bucket.s3-af-south-1.amazonaws.com

[ennru]

Yes, AWS have cleaned up their special host names for different regions since Alpakka S3 was implemented initially, and I'm sure it can be simplified and improved. Please feel free to check out the code and see what needs to be done.

A more immediate solution might be to set the endpoint URL via settings:

alpakka/s3/src/main/resources/reference.conf

Lines 87 to 91 in 5534c61

	# Custom endpoint url, used for alternate s3 implementations
	# To enable virtual-host-style access with Alpakka S3 use the placeholder `{bucket}` in the URL
	# eg. endpoint-url = "http://{bucket}.s3minio.alpakka:9000"
	#
	# endpoint-url = null

See even #1558

[ennru]

Fixed with #2336