Make direct_vms a relation

[kbrock]

You can preload a relation.
You can not preload a method.

Older code in virtual_attributes and rails was more lenient and would not complain.
Newer versions of the gems are more picky.

Failure/Error: preloader.preload(records, associations, preload_scope)
      
ActiveRecord::AssociationNotFoundError:
  Association named 'direct_vms' was not found on Service; perhaps you misspelled it?

We have 2 options:

1. Remove the preload.
2. Convert direct_vms to a virtual_has_many. <== we chose this

LJ was more comfortable converting it to a virtual relation.

[NickLaMuro]

@kbrock do you mind putting in the steps on how or where you did the test to determine this? I am sure this probably is a bug, but it would be nice to have some proof on how to replicate in the future in case this causes a regression.

Otherwise it looks good to me.

[kbrock]

The older versions of virtual attributes just ate errors (as we've complained about in a number of PRs)
The newer version of virtual attributes throws an error if you attempt to preload a relation that isn't a valid relation.

[kbrock]

wip: determining if this is indeed a problem

[kbrock]

@NickLaMuro thanks for this comment. I'll change something in virtual attributes.

The definition of Preloader.preload [ref] is pretty straight forward:

Implements the details of eager loading of Active Record associations

preload was made for associations. Service defines direct_vms, but it is not a virtual association, and it does not define a :uses. So the preload will do nothing.

[kbrock]

via @jrafanie

lets add virtual has many:

virtual_has_many   :direct_vms

[miq-bot]

Checked commit kbrock@92401ca with ruby 2.4.6, rubocop 0.69.0, haml-lint 0.20.0, and yamllint 1.10.0
1 file checked, 0 offenses detected
Everything looks fine. 🏆