[RATIS-208] Allow client to specify replication level in a request

• Type: New Feature
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.2.0
• Assignee: Kit Hui
• Reporter: Tsz-wo Sze
• Created: 07/Feb/18 01:52
• Updated: 10/Apr/18 14:27
• Resolved: 10/Apr/18 11:13

Description

In Raft protocol, the leader sends a reply to client once the request is committed and applied to its state machine. A request is committed when the leader get a majority of responses from all the members in the raft group.

In some applications, the client may want to wait for all member responses instead of a majority. For example, the application wants to support reading even if there is only one machine remaining in the group.