Add a convenience target to use when debugging topologies locally

[l03wn3]

https://issues.apache.org/jira/browse/STORM-759

It would be really nice if there was a storm target like "jar", but one that would pause and wait for a remote java debugger so you could debug your topology while running locally.
Incidentally, here's a more or less trivial fix for this.

[Parth-Brahmbhatt]

you could just use the storm jar command and provide the debug args as topology.worker.childopts config. I don't think we need a special command for this.

[l03wn3]

Doing
Config conf = new Config();
conf.put(Config.TOPOLOGY_WORKER_CHILDOPTS, "-agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=5005");

Doesn't make the JVM suspend upon start and wait for a debugger. Would there be another convenient way?

[HeartSaVioR]

@Parth-Brahmbhatt
Maybe @l03wn3 want to attach debugger with main process which submits topology, not deployed workers. But still I agree it doesn't need to add special command.

@l03wn3
If I know "storm.py" right, for now you can try adding your arguments to system environment STORM_JAR_JVM_OPTS before executing "storm jar".
Sure you can restore STORM_JAR_JVM_OPTS after doing this.

[Parth-Brahmbhatt]

in that case you are right , if you want to test in local mode you should use STORM_JAR_JVM_OPTS.

[lazyval]

@Parth-Brahmbhatt +1

[d2r]

@l03wn3, is STORM_JAR_JVM_OPTS OK for debugging this way?

If so, would you close this pull request? Otherwise, would you create a Jira issue for this change?

[knusbaum]

Closing this. Please reopen if it's still an issue.