Perfomance fix for Object Storage Manager deletion

[aiperon]

Recently, the inventorying of S3 objects was merged to the master.
ManageIQ/manageiq-providers-amazon#123
Since a lot of objects could be stored on S3, user wouldn't be able to delete Amazon provider.

This fix allows destroying of storage manager with 40K objects in 40 seconds.

@roliveri please, review

@miq-bot add_label euwe/no, providers, providers/storage, performance

[miq-bot]

Checked commit xlab-si@9215caa with ruby 2.2.6, rubocop 0.47.1, and haml-lint 0.20.0
1 file checked, 0 offenses detected
Everything looks good. 🍪

[Ladas]

@aiperon @roliveri so, this has a funky side effect for the refresh. If there is :dependent => :destroy missing, the refresh saving code does not delete the missing objects.

It uses association.delete(deletes), where association is ems.cloud_object_store_objects

This affect only old refresh, not graph refresh

[aiperon]

@Ladas Should I fix this spec?

[Ladas]

@aiperon @roliveri disabling the spec in ManageIQ/manageiq-providers-amazon#148, could you guys figure out the way to pass the spec? This might be even a rails bug, cause I would not expect this would be interconnected like this.

[Ladas]

@aiperon if you know how? :-) I am disabling it for now, so it doesn't block the AWS, with the knowledge that the refresh will create zombies for OpenStack and AWS old refresh

[aiperon]

So, we (or I) need to fix the old refresh.

[Ladas]

It might be, it's something already fixed in Rails master :-)

The hack that would not require changing of the saving_code (not sure if we can, it's the shared one) would be doing disconnect_inv method that would call destroy, on the cloud_object_store_object model. Then it will not be calling the association.delete

[Ladas]

the code is here https://github.com/Ladas/manageiq/blob/48aa323551c8825e02170e251afa717ca807d2ed/app/models/ems_refresh/save_inventory_helper.rb#L65-L65

so we need disconnect_inv method and passing disconnect = true here https://github.com/Ladas/manageiq/blob/1bbb4fcef58c1f852f7e983c43153b0457cf214c/app/models/ems_refresh/save_inventory_object_storage.rb#L80-L80

[Ladas]

it's ugly, but acceptable for me, given all ^ code will hopefully be deleted soon :-D @roliveri is that fine with you?

[roliveri]

@Ladas That's OK with me.

[Ladas]

@aiperon should I send the fix, or you are working on that?

[aiperon]

@Ladas, please do it. I haven't worked on that yet.