Add ability to update a coordinator's definition

[sabidib]

This adds the ability to update a coordinator's definition without killing and recreating the coordinator.

According to the docs a coordinator's definition can only be updated if the following are not changed:

• coordinator name
• frequency
• start time
• end time
• timezone

If any of these are changed, then there should be a hard failure on the request.

I couldn't find anything specific on what coordinator states allow for an update so I assumed we would only want to update coordinators that are active or running or suspended.

Curious if updating a coordinator in a suspended state makes sense. @kmtaylor-github @cfournie Thoughts?

[kmtaylor-github]

Curious if updating a coordinator in a suspended state makes sense.

Yes! This is actually a really important usecase. A deploy shouldn't skip a suspended coord, nor should it resume it.

[sabidib]

I gave this a test spin with a local instance of oozie and switched a coordinator between the minimal coordinator and the full coordinator successfully. The diffs made sense as well. It also handled "updating" to the same coordinator xml showing an empty diff.

[kmtaylor-github]

It also handled "updating" to the same coordinator xml showing an empty diff.

Presumably this was with identical config data?

[sabidib]

Presumably this was with identical config data?

Yes, the configuration was the same.

[sabidib]

Any outstanding comments left?