Permit to have a action plugin without a empty module file

[mscherer]

ISSUE TYPE

• Feature Pull Request

COMPONENT NAME

ansible

SUMMARY

Currently, someone writing a action plugin will also need
to have a empty file in the module path to avoid triggering
the error "no action detected in task.".

This PR verify that either a module or a action plugin correspond to a task, permitting to action plugin without a empty file (in case that's purely a action plugin controller side)

( cc @dmsimard )

[bcoca]

they should really have module file as it is only way to document the plugin

[dmsimard]

@bcoca so we need to have an empty module file with just the DOCUMENTATION and EXAMPLE strings?

[mscherer]

For a external plugin, yeah. For a private one, that seems rather counter intuitive.

[bcoca]

ansible-doc still works with private plugins, its a nice way for them to give docs to users that didn't write them or forgot what they did 3 months ago and what the options mean.

[dmsimard]

It requires an extra configuration step, though. That means you do not only need to specify an action_plugins path but also a library path. A bit awkward IMO.

Would it not be possible to embed the doc directly in the action module ? Is there a limitation ?

Sorry if I sound naive, I'm not familiar with this bit of code. Genuine question.

[mscherer]

It is possible, here is a fix, so now, if we have a action plugin, ansible-doc will also be able to get doc from the plugin. (code could surely be refactored a bit, but just to see if we agree on the basics)

[mattclay]

CI is failing nearly all test jobs with the error:

2017-02-01 23:47:13 ERROR! conflicting action statements

Full logs for one of the failed jobs here: https://app.shippable.com/runs/58926c7bf2e87f0f00908e8e/7/console

[jimi-c]

Rebased this myself and merged in 4811c7f.

Thanks!