[SOLR-15590] Start up Core Container via ServletContextListener

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 9.0
• Fix Version/s: 9.0
• Assignee: Gus Heck
• Reporter: Gus Heck
• Created: 17/Aug/21 14:03
• Updated: 15/Jan/24 07:56
• Resolved: 25/Mar/22 20:12

Description

Anyone who has had to work on HttpSolrCall,  or SolrDispatchFilter will have noticed that we have a LOT going on and that it gets very convoluted. This is bad for maintenance, and probably also bad for performance.  After reading for a while I suspect that the primary thing that has lead to this is that the only way to get a reference to CoreContainer is to be in or initialized in or invoked by the SolrDispatchFilter or HttpSolrCall classes.

To isolate the startup code and not distract from the dispatch code and also to make it possible to later add features that don't live in SolrDispatchFilter and also possibly to split out some features from SolrDispatchFilter into servlets or separate filters, this ticket moves CoreContainer into a CoreService class that will provide CoreContainer and a few other objects like the httpclient to other components that need it.

Issue Links

• breaks: SOLR-16086 Issues with TestReplicationHandler.doTestIndexFetchOnLeaderRestart
• causes: SOLR-17118 Solr deadlock during servlet container start
• links to: GitHub Pull Request #265
• links to: GitHub Pull Request #397
• links to: GitHub Pull Request #416
• links to: GitHub Pull Request #445
• links to: GitHub Pull Request #761