[Bug] Cannot eagerly load the polymorphic association :resource in performance report

[lpichler]

Reproducer:

replace context "performance reports" in
./spec/models/miq_report_spec.rb

   context "performance reports" do
      let(:report) do
        MiqReport.new(
            :title   => "vim_perf_daily.yaml",
            :db      => "VimPerformanceDaily",
            :cols    => %w(timestamp cpu_usagemhz_rate_average max_derived_cpu_available resource.derived_memory_used_low_over_time_period),
            :include => {"resource" => {"columms" => 'derived_memory_used_low_over_time_period'}})
      end

      before do
        EvmSpecHelper.local_miq_server
        ems = FactoryBot.create(:ems_vmware)
        vm = FactoryBot.create(:vm_vmware, :ext_management_system => ems)
        time_profile = FactoryBot.create(:time_profile_utc)
        FactoryBot.create(:metric_rollup_vm_daily, :resource => vm, :time_profile => time_profile)
      end

      it "runs report" do
        report.generate_table(:userid => "admin")
      end
    end

run and then you will get error message:
polymorphic association :resource in performance report

this error is also in UI(toolbar button Monitoring -> Utilization on VM summary screen) when those yaml are used:

➜  manageiq git:(master) ✗ ag 'resource:' ./ --yaml
Thu Dec 19 16:13:43 CET 2019
product/charts/miq_reports/vim_perf_daily.yaml
80:  resource:

product/charts/miq_reports/vim_perf_daily_cloud.yaml
78:  resource:

Caused by

most likely by #19127
and issue is only on upstream (no on ivanchuck, no on hammer )

I am not sure about proper fix but it looks we need to somehow include this condition
https://github.com/ManageIQ/manageiq/pull/19127/files#diff-8d948055de14ced0e63abf9637a9a788L415

Feel free to use my spec in your PR.

@kbrock as you author of the #19127 maybe you will know better how to fix it.

cc @NickLaMuro

thanks !

[lpichler]

@miq-bot add_label bug

[kbrock]

fun stuff:

# fails
MetricRollup.includes(:resource, :time_profile).references("time_profiles").first
# works
MetricRollup.preload(:resource).includes(:time_profile).references("time_profiles").first
MetricRollup.includes(:resource).first
MetricRollup.includes(:time_profile).references("time_profiles").first
MetricRollup.preload(:resource, :time_profile).includes(:time_profile).references("time_profiles").first

# NEW:
# works
MetricRollup.preload(:resource, :time_profile).eager_load(:time_profile).first

reproducer coded up in master...kbrock:polymorphic_through

[martinpovolny]

Similar problem from the UI side.

Go to Compute --> Infra --> VMs
Select a VM, go to details.
Then in the menu choose (toolbar) Monitoring --> Utilization)

A task is fired at this point through the queue. And the task will fail with a stacktrace in the EVM log. Unfortunately there's no error handling for the failed task so the UI will end up in an infinite busy-wait loop.

[----] E, [2020-01-22T15:53:45.501409 #467320:da85e0] ERROR -- : [ActiveRecord::EagerLoadPolymorphicError]: Cannot eagerly load the polymorphic association :resource  Method:[block (2 levels) in <class:LogProxy>
]
[----] E, [2020-01-22T15:53:45.501573 #467320:da85e0] ERROR -- : /home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-5.1.7/lib/active_record/associations/join_dependency.rb:244:in `block in build'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-5.1.7/lib/active_record/associations/join_dependency.rb:237:in `each'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-5.1.7/lib/active_record/associations/join_dependency.rb:237:in `map'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-5.1.7/lib/active_record/associations/join_dependency.rb:237:in `build'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-5.1.7/lib/active_record/associations/join_dependency.rb:99:in `initialize'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-5.1.7/lib/active_record/relation/finder_methods.rb:392:in `new'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-5.1.7/lib/active_record/relation/finder_methods.rb:392:in `construct_join_dependency'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-5.1.7/lib/active_record/relation/finder_methods.rb:368:in `find_with_associations'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-virtual_attributes-1.5.0/lib/active_record/virtual_attributes/virtual_fields.rb:311:in `find_with_associations'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-virtual_attributes-1.5.0/lib/active_record/virtual_attributes/virtual_fields.rb:313:in `find_with_associations'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-5.1.7/lib/active_record/relation.rb:669:in `exec_queries'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-5.1.7/lib/active_record/relation.rb:546:in `load'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-5.1.7/lib/active_record/relation.rb:255:in `records'
/home/martin/.rvm/gems/ruby-2.5.5/gems/activerecord-5.1.7/lib/active_record/relation/delegation.rb:39:in `each'
/home/martin/Projects/manageiq/app/models/metric/helper.rb:129:in `sort_by'
/home/martin/Projects/manageiq/app/models/metric/helper.rb:129:in `remove_duplicate_timestamps'
/home/martin/Projects/manageiq/app/models/miq_report/generator.rb:330:in `generate_basic_results'
/home/martin/Projects/manageiq/app/models/miq_report/generator.rb:204:in `_generate_table'
/home/martin/Projects/manageiq/app/models/miq_report/generator.rb:185:in `block in generate_table'
/home/martin/Projects/manageiq/app/models/user.rb:295:in `with_user'
/home/martin/Projects/manageiq/app/models/miq_report/generator.rb:185:in `generate_table'
/home/martin/Projects/manageiq/app/models/miq_report/generator/async.rb:33:in `block in _async_generate_tables'
/home/martin/Projects/manageiq/app/models/miq_report/generator/async.rb:32:in `each'
/home/martin/Projects/manageiq/app/models/miq_report/generator/async.rb:32:in `each_with_index'

[skateman]

@kbrock I'm kinda blocked by this 😕 in resolving ManageIQ/manageiq-ui-classic#6534

[chessbyte]

@kbrock @NickLaMuro what is the status of this issue?

[NickLaMuro]

@chessbyte sorry for the lack of a follow up on here, but #19804 should have fixed this issue.

[chessbyte]

@NickLaMuro can you validate the reproducer here is addressed.

[NickLaMuro]

@chessbyte the specs that were added from the PR should do just that:

• https://github.com/ManageIQ/manageiq/pull/19804/files#diff-d8dd6082fb3fffd485c63c555aca8874R758-R764
• https://github.com/ManageIQ/manageiq/pull/19804/files#diff-d8dd6082fb3fffd485c63c555aca8874R776-R784

@kbrock since you wrote those specs, can you sanity check me on that claim?

[kbrock]

@chessbyte @NickLaMuro Yes, The report spec is the reproducer from Libor.

[chessbyte]

@kbrock @NickLaMuro so can this issue be closed as resolved?

[chessbyte]

@lpichler is this issue fixed?

[NickLaMuro]

@kbrock @NickLaMuro so can this issue be closed as resolved?

@chessbyte For what it is worth, I have asked David to test it out in gitter:

https://gitter.im/ManageIQ/manageiq?at=5e3c3b58dc52c34ace4d01f2

And he said that it fixed his issue as well.

[skateman]

It fixed the issue I was experiencing.