Return empty array for delegation with nil manager

[kbrock]

If a NetworkManager doesn't have a parent_manager (e.g. Nuage) return an empty array instead of a nil

Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1767747

Alternative to #19459 by @agrare

[miq-bot]

Checked commit kbrock@c475153 with ruby 2.4.6, rubocop 0.69.0, haml-lint 0.20.0, and yamllint 1.10.0
2 files checked, 19 offenses detected

app/models/manageiq/providers/network_manager.rb

• ❗ - Line 38, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 39, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 40, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 41, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 42, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 43, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 44, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 45, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 46, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 47, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 48, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 49, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 50, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 51, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 52, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 53, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 54, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 55, Col 5 - Rails/InverseOf - Specify an :inverse_of option.
• ❗ - Line 56, Col 5 - Rails/InverseOf - Specify an :inverse_of option.

[agrare]

👍 looks good

[mzazrivec]

Rails console after this change:

irb(main):002:0> MiqExpression.miq_adv_search_lists('CloudNetwork', :exp_available_finds)
PostgreSQLAdapter#log_after_checkout, connection_pool: size: 30, connections: 1, in use: 1, waiting_in_queue: 0
Traceback (most recent call last):
       16: from railties (5.1.7) lib/rails/commands/console/console_command.rb:97:in `perform'
       15: from railties (5.1.7) lib/rails/commands/console/console_command.rb:17:in `start'
       14: from railties (5.1.7) lib/rails/commands/console/console_command.rb:62:in `start'
       13: from (irb):2
       12: from lib/miq_expression.rb:903:in `miq_adv_search_lists'
       11: from lib/miq_expression.rb:802:in `model_details'
       10: from lib/miq_expression.rb:891:in `get_relats'
        9: from lib/miq_expression.rb:942:in `build_relats'
        8: from lib/miq_expression.rb:942:in `each'
        7: from lib/miq_expression.rb:973:in `block in build_relats'
        6: from lib/miq_expression.rb:942:in `build_relats'
        5: from lib/miq_expression.rb:942:in `each'
        4: from lib/miq_expression.rb:952:in `block in build_relats'
        3: from activerecord (5.1.7) lib/active_record/reflection.rb:404:in `klass'
        2: from activerecord (5.1.7) lib/active_record/reflection.rb:408:in `compute_class'
        1: from activerecord (5.1.7) lib/active_record/inheritance.rb:166:in `compute_type'
NameError (uninitialized constant ManageIQ::Providers::NetworkManager::AuthKeyPair)

And the following CI failures in ui-classis: https://travis-ci.org/ManageIQ/manageiq-ui-classic/jobs/608753209?utm_medium=notification&utm_source=github_status

[martinpovolny]

I think that this PR nicely shows that the idea of running the tests on the other repos (UI) only on demand is not that great.

[lpichler]

@kbrock

1. for :key_pairs maybe you wanted to use something likes this:

has_many :key_pairs, -> { where.not(:resource_id => nil) }, :class_name => "Authentication", :as => :resource

2. moving relations from :delegate to many :has_many puts this relations to the reflections.
   so this method starts to return reflections_with_virtual them for example in MiqExpression.build_relats here and this is source of error.

[simaishi]

@kbrock Can this be ivanchuk/yes?

[kbrock]

Note: if you merge this, you also need #19486 which undoes one of the changes

[simaishi]

Ivanchuk backport details:

$ git log -1
commit a195152a4b57fd56956c774295972489db6d3abd
Author: Adam Grare <[email protected]>
Date:   Thu Nov 7 08:51:57 2019 -0500

    Merge pull request #19473 from kbrock/bz_1767747_fix_network_manager_delegate_without_parent_manager

    Return empty array for delegation with nil manager

    (cherry picked from commit fe3f8ea91a23a88195aa9879913a5b0180b30e56)

    Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1785374