Apache Knox's gateway is nice in that it can provide centralized authentication and authorization for a collection of service. Additionally, it can expose "private" nodes through a single point (e.g. a gateway). This makes our life as developers much easier in cloud deployments where it's not straightforward to access nodes (e.g. they're running on some private network).
KNOX-1866 captures the changes over there required to make HBase's proxying actually work (definition lives there), but there were a few things we do in our UI which made it hard/impossible to proxy it correctly.
- ProfilerServlet was dropping extra query parameters in the URL
- JSON task output on master/regionserver couldn't be disambiguated
- Some missing /master-status and /rs-status links couldn't be disambiguated properly due to a lack of context
- Missing content-type set on a profiler servlet response