[FLUME-2308] Document requirements for custom source

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Not A Problem
• Component/s: Docs
• Assignee: Unassigned
• Reporter: Joshua Hyde
• Created: 31/Jan/14 21:48
• Updated: 04/May/14 04:21
• Resolved: 01/Feb/14 14:36

Description

I implemented my own custom source that extends org.apache.flume.source.AbstractSource; to my surprise, however, I saw this in my logs:

31 Jan 2014 15:40:11,289 ERROR [conf-file-poller-0] (org.apache.flume.node.AbstractConfigurationProvider.loadSources:366)  - Source basset_source has been removed due to an error during configuration
java.lang.IllegalArgumentException: No known runner type for source com.example.MySource{name:basset_source,state:IDLE}
	at org.apache.flume.SourceRunner.forSource(SourceRunner.java:54)
	at org.apache.flume.node.AbstractConfigurationProvider.loadSources(AbstractConfigurationProvider.java:355)
	at org.apache.flume.node.AbstractConfigurationProvider.getConfiguration(AbstractConfigurationProvider.java:102)
	at org.apache.flume.node.PollingPropertiesFileConfigurationProvider$FileWatcherRunnable.run(PollingPropertiesFileConfigurationProvider.java:140)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
	at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:304)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:178)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:744)

The solution, it appears, is mentioned in this StackOverflow question:

i think i figured it out. The documentation on the Flume website does not mention a custom implementation should implement not the Source interface but either the EventDrivenSource or PollableSource interface.

It would be helpful if this was, as mentioned, written in the user-facing documentation.