allow for only starting if needed

[mwhipple]

I'm presently using this plugin to manage an external process that isn't strictly tied to the build lifecycle, so it would be nice if the plugin had some additional logic to handle cases where it may already be running or may not be expected to be immediately cleaned up.

Presently I've started with using onlyIf{!pidFile} but it would be nice to have that be more expressive and set up to evolve.

I can see about putting a PR together at some point in the not too distant future or if I have something more substantial.

[abigpotostew]

upvote. I would like to be able to add a dependency that the process is alive, and start it if needed.

[gorky]

Workaround:
task stopTask(type: KillProcessTask,...){
onlyIf ({return new File(directory, pidLockFileName).exists()})
...
}
task startTask(type: SpawnProcessTask,....){
onlyIf ({return !new File(directory, pidLockFileName).exists()})
...
}