Dialog#destroy should ignore resource actions linking nonexisting entities

[himdel]

Currently, if you have a Dialog associated with a Custom Button,
and delete the custom button (as opposed to destroy; that should not happen, but apparently does),

deleting the dialog will fail, because ra.resource_type.constantize.find(ra.resource_id) throws an exception as the resource no longer exists. (The resource being a removed custom button.)

So, updating reject_if_has_resource_action to ignore resource actions pointing to nonexistent resources.

Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1770300
@miq-bot add_label bug, hammer/yes, ivanchuk/yes

---

I'm more convinced that this fixes the BZ, than that the problem is something we should fix.
However, for custom buttons, this is not the first time it happened (#19573 and ManageIQ/manageiq-schema#370 being mildly related),
so IMO it makes sense to make sure we don't crash in such situations.

Cc @d-m-u, feel free to disagree ;)

[d-m-u]

So while conceptually I disagree since I think the issue's entirely self-inflicted, this looks good and I'm fine with it irl.

Thanks for the help, @himdel.

[miq-bot]

Checked commit https://github.com/himdel/manageiq/commit/773a1547fb99d0fb1b91d28ce1f6ce5f53f44490 with ruby 2.5.5, rubocop 0.69.0, haml-lint 0.20.0, and yamllint 1.10.0
2 files checked, 3 offenses detected

app/models/dialog.rb

• ❗ - Line 199, Col 8 - Style/NumericPredicate - Use connected_components.length.positive? instead of connected_components.length > 0.
• ❗ - Line 199, Col 8 - Style/ZeroLengthPredicate - Use !empty? instead of length > 0.

spec/models/dialog_spec.rb

• ❗ - Line 128, Col 27 - Layout/ExtraSpacing - Unnecessary spacing detected.

[simaishi]

Hammer backport details:

$ git log -1
commit a335940e4946974b3dd4420425573851865398b0
Author: Harpreet Kataria <[email protected]>
Date:   Mon Dec 9 11:01:18 2019 -0500

    Merge pull request #19574 from himdel/bz1770300

    Dialog#destroy should ignore resource actions linking nonexisting entities

    (cherry picked from commit 79a77cdcb9ff3254843a5388f23c0020b8a729d4)

    Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1783383

[simaishi]

@himdel Travis is failing in hammer branch. Please take a look.

  1) Dialog#destroy does destroy dialog with only obsolete resource_action association
     Failure/Error: FactoryBot.create(:resource_action, :action => nil, :dialog => dialog, :resource_type => 'CustomButton', :resource_id => custom_button.id)
     
     NameError:
       undefined local variable or method `dialog' for #<RSpec::ExampleGroups::Dialog::Destroy:0x000000001e7e8c40>
     # ./spec/models/dialog_spec.rb:124:in `block (3 levels) in <top (required)>'

[himdel]

It's because hammer is missing the fixes from #18479, that one is hammer/no, creating a custom PR to add the let(:dialog) bit... #19646

[simaishi]

Ivanchuk backport details:

$ git log -1
commit 613cfaa32b1206ded773049054e17f738999b506
Author: Harpreet Kataria <[email protected]>
Date:   Mon Dec 9 11:01:18 2019 -0500

    Merge pull request #19574 from himdel/bz1770300

    Dialog#destroy should ignore resource actions linking nonexisting entities

    (cherry picked from commit 79a77cdcb9ff3254843a5388f23c0020b8a729d4)

    Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1783382