[SOLR-16628] Occasional resource leak around XmlConfigFile parsing

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 8.9
• Fix Version/s: 9.2
• Assignee: Michael Gibney
• Reporter: Michael Gibney
• Created: 18/Jan/23 22:04
• Updated: 27/Mar/23 18:04
• Resolved: 09/Feb/23 18:58

Description

Currently, xml config file parsing can in exceptional circumstances lead to resource leaks (InputStream not being closed). This has occasionally shown up in tests and presumably could also manifest in the wild.

I suspect (but am not certain) that these changes may have been introduced in version 8.9 by SOLR-15337 (closing of byte streams in xml parsing is unusual iiuc in that according to spec, closing is handled internal to the parser, so it's easy to rely on that behavior and things will usually be ok. But we should take extra steps to ensure the InputStreams are always closed).

Issue Links

• relates to: SOLR-15337 Avoid XPath in solrconfig.xml parsing
• relates to: SOLR-16336 avoid fetching solrconfig.xml & schema.xml for already cached schema and config
• links to: GitHub Pull Request #1302