Affects Version/s: 2.6.0
Fix Version/s: None
The YARN registry implementation in hadoop 2.6 implemented the core ZK client of the registry API; a client library needing no servers other than the ZK quorum. This has good availability, but does not work outside the cluster (unless ZK is accessible). It also uses ZK's SASL client which is somewhat fiddly (you need to set system properties for it to work)
For remote/long haul access we need a REST equivalent, one that proxies. This REST service is also needed to work with clients in other languages.
This issue proposes
- implementing a web application to offer read access to the registry to all
- to support write access to authenticated users (with access restricted to their part of the /users tree)
- providing an implementation of RegistryOperations which uses this API, offering authenticated and unauthenticated access to the REST service.
- extending the RM to optionally support this.
The registry client API has been designed from the outset to work with REST APIs: a potentially connectionless Yarn service with simple put/get/delete operations; the naming scheme also chosen for REST paths as well as DNS.