[SOLR-9090] solrj CloudSolrClient: add directUpdatesToLeadersOnly support

• Type: New Feature
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 6.2, 7.0
• Component/s: SolrJ
• Assignee: Christine Poerschke
• Reporter: Christine Poerschke
• Created: 09/May/16 11:42
• Updated: 18/Oct/17 12:12
• Resolved: 13/Jul/16 16:19

Description

solrj CloudSolrClient: add directUpdatesToLeadersOnly support

(Marvin Justice, Christine Poerschke)

Proposed change:

• Addition of a directUpdatesToLeadersOnly flag to allow clients to request that direct updates be sent to the shard leaders and only to the shard leaders.

Motivation:

• In a scenario where there is temporarily no shard leader the update request will 'fail fast' allowing the client to handle retry logic.

Related tickets:

• SOLR-6312 concerns the ((currently) no longer used) updatesToLeaders flag. The updatesToLeaders logic however appears to be slightly different from the proposed directUpdatesToLeadersOnly logic: updatesToLeaders indicates that sending to leaders is preferred but not mandatory whereas directUpdatesToLeadersOnly mandates sending to leaders only.

Issue Links

• is related to: SOLR-6312 CloudSolrServer doesn't honor updatesToLeaders constructor argument
• relates to: SOLR-9512 CloudSolrClient's cluster state cache can break direct updates to leaders
• relates to: SOLR-11507 simplify and extend SolrTestCaseJ4.CloudSolrClientBuilder randomisation
• relates to: SOLR-9464 change CloudSolrClient[Builder].directUpdatesToLeadersOnly default (to true)
• relates to: SOLR-9067 solrj CloudSolrClient's updatesToLeaders flag is never used