[BOOKKEEPER-918] Create Ledger NameSpace

• Type: New Feature
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: bookkeeper-client, bookkeeper-server
• Labels: ghmigrated iktriage1
• Assignee: JV Jujjuri
• Reporter: JV Jujjuri
• Created: 07/Apr/16 14:22
• Updated: 17/Oct/17 21:28

Description

Bookkeeper doesn't really have a real NameSpace, it operates by ledgerId. I have opened and worked on https://issues.apache.org/jira/browse/BOOKKEEPER-873 which allows applications to pass-in LedgerId instead of BK client API picking one for them. But that really doesn't offer much flexibility.

Since ledgerId is a long we can't have 128-bit UUIDs as ledgerIDs and this severely restricts the range if we are generating ledgerIDs through a random generator (https://issues.apache.org/jira/browse/BOOKKEEPER-864)

Best solution for this is to offer a real name space, and I believe it is relatively simple than offering 128-bit ledgerIDs.

Analogous to regular filesystem, we treat our ledgerId as inode-number. Create a new name space in ZK with the user provided pretty-name and provide simple mapping at ZK between name-to-ledgerId. This mapping is static, and never changes once created. i.e name-x always points ledgerId-z. Given this most part of bookie code doesn't need to be aware of this mapping, and changes mostly will be confined client code and in create/delete/list paths.