[HBASE-7411] Use Netflix's Curator zookeeper library

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Won't Fix
• Affects Version/s: 0.95.2
• Component/s: Zookeeper
• Assignee: Unassigned
• Reporter: Enis Soztutar
• Created: 20/Dec/12 22:31
• Updated: 15/Jun/22 21:07
• Resolved: 26/Sep/17 19:54

Description

We have mentioned using the Curator library (https://github.com/Netflix/curator) elsewhere but we can continue the discussion in this.

The advantages for the curator lib over ours are the recipes. We have very similar retrying mechanism, and we don't need much of the nice client-API layer.
We also have similar Listener interface, etc.

I think we can decide on one of the following options:
1. Do not depend on curator. We have some of the recipes, and some custom recipes (ZKAssign, Leader election, etc already working, locks in HBASE-5991, etc). We can also copy / fork some code from there.
2. Replace all of our zk usage / connection management to curator. We may keep the current set of API's as a thin wrapper.
3. Use our own connection management / retry logic, and build a custom CuratorFramework implementation for the curator recipes. This will keep the current zk logic/code intact, and allow us to use curator-recipes as we see fit.
4. Allow both curator and our zk layer to manage the connection. We will still have 1 connection, but 2 abstraction layers sharing it. This is the easiest to implement, but a freak show?

I have a patch for 4, and now prototyping 2 or 3 whichever will be less painful.

Related issues:
HBASE-5547
HBASE-7305
HBASE-7212

Issue Links

• relates to: HBASE-16835 Revisit the zookeeper usage at client side