[STORM-3624] Race condition on ArtifactoryConfigLoader.load

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.0.0, 2.1.0, 2.2.0
• Fix Version/s: 2.3.0
• Component/s: storm-server
• Labels: pull-request-available
• Assignee: Ethan Li
• Reporter: Ethan Li
• Created: 15/Apr/20 21:43
• Updated: 01/Jul/20 13:59
• Resolved: 15/Jun/20 15:08

Description

https://github.com/apache/storm/blob/master/storm-server/src/main/java/org/apache/storm/scheduler/resource/ResourceAwareScheduler.java#L100-L102

config() is called in multiple threads. But ArtifactoryConfigLoader.load is not thread-safe. For example, https://github.com/apache/storm/blob/master/storm-server/src/main/java/org/apache/storm/scheduler/utils/ArtifactoryConfigLoader.java#L181-L187

JSONObject returnValue;
        try {
            returnValue = (JSONObject) jsonParser.parse(metadataStr);
        } catch (ParseException e) {
            LOG.error("Could not parse JSON string {}", metadataStr, e);
            return null;
        }

Multiple threads use the same jsonParser and since JsonParser is not thread-safe, the return value will be corrupted.

I propose to create a separate thread to load scheduler configs periodically. This also makes the config loading logic cleaner.

Issue Links

• links to: GitHub Pull Request #3249