[MINIFI-128] NPE if nifi.minifi.notifier.file.config.path wasn't configured

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 0.0.1
• Fix Version/s: 0.2.0
• Component/s: Agent Configuration/Installation
• Environment: current master branch build
• Assignee: Aldrin Piri
• Reporter: Andrew Grande
• Created: 27/Oct/16 17:03
• Updated: 22/Dec/16 21:44
• Resolved: 22/Dec/16 21:44

Description

When enabling a FileChangeNotifier, it's easy to forget uncommenting the nifi.minifi.notifier.file.config.path property (required). Minifi restart will throw an unfriendly error:

Exception in thread "main" java.lang.IllegalArgumentException: Property, nifi.minifi.notifier.file.config.path, for the path of the config file must be specified.
        at org.apache.nifi.minifi.bootstrap.configuration.notifiers.FileChangeNotifier.initialize(FileChangeNotifier.java:154)
        at org.apache.nifi.minifi.bootstrap.RunMiNiFi.initializeNotifiers(RunMiNiFi.java:1452)
        at org.apache.nifi.minifi.bootstrap.RunMiNiFi.start(RunMiNiFi.java:1116)
        at org.apache.nifi.minifi.bootstrap.RunMiNiFi.main(RunMiNiFi.java:224)
Initiating shutdown of bootstrap change notifiers...
Exception in thread "Thread-2" java.lang.NullPointerException
        at java.util.Collections$UnmodifiableCollection.<init>(Collections.java:1026)
        at java.util.Collections$UnmodifiableSet.<init>(Collections.java:1128)
        at java.util.Collections.unmodifiableSet(Collections.java:1118)
        at org.apache.nifi.minifi.bootstrap.RunMiNiFi.getChangeNotifiers(RunMiNiFi.java:1438)
        at org.apache.nifi.minifi.bootstrap.ShutdownHook.run(ShutdownHook.java:57)

Expected: improve the error message to be meaningful and suggest the user configure the property. No stacktrace, as we know what's going on exactly.

Issue Links

• links to: GitHub Pull Request #68