Github user aljoscha commented on the issue:
https://github.com/apache/flink/pull/4607
I think we won't merge this as is. There are some thoughts flying around
for reworking the BucketingSink to use our own `FileSystem` implementation and
also making it work well with S3. I'm quite sure that this work will land in
1.6 but we have to release 1.5 now because it's already late.---
