Delete property only if it exists

[ogajduse]

fixes #199

In case when VM inventory != default inventory:
Broker tries to delete the inventory attribute (cached_property) even though it is not evaluated yet. That results in 'AnsibleTower' object has no attribute 'inventory'

I propose to check whether it was evaluated using __dict__ first and then safely delete it.

[LadislavVasina1]

[Griffin-Sullivan]

So I can test this by checking out and specifying an inventory that is not the default inventory and then try to extend it?

[ogajduse]

So I can test this by checking out and specifying an inventory that is not the default inventory and then try to extend it?

Exactly 👍

[Griffin-Sullivan]

I can't seem to reproduce the error on master. Maybe you could help me edit these steps:

1. Set default_inventory in broker_settings.yaml to rhv
2. Checkout VM but specify osp as inventory
3. Extend the VM

[LadislavVasina1]

@Griffin-Sullivan I have added some additional info to the issue Issue#199.
I was able to reproduce this error with these steps:

1. Have osp set as a default in broker_settings_yaml
2. Have any VM deployed on rhv in my inventory
3. Try to extend (everything or just VM deployed on rhv)

[Griffin-Sullivan]

Ok I was able to reproduce the error and the PR is fixing the issue. One note about hitting this issue. If you do a checkout without a sync, you won't hit this error, but after syncing you should hit it. The reason is the tower_inventory attribute is only present in the _broker_args before the sync, but after the sync you can see tower_inventory under the host's details and the _broker_args.

[ogajduse]

Ok I was able to reproduce the error and the PR is fixing the issue. One note about hitting this issue. If you do a checkout without a sync, you won't hit this error, but after syncing you should hit it. The reason is the tower_inventory attribute is only present in the _broker_args before the sync, but after the sync you can see tower_inventory under the host's details and the _broker_args.

@JacobCallahan That missing tower_inventory before the sync smells like a bug to me. 🤔

[JacobCallahan]

Nice find and solve!

@ogajduse if you want to take a shot at the specific issue @Griffin-Sullivan detailed, that would need to be something added to the initial host creation. One possible way would be to add an else to this conditional block and manually setting the tower_inventory to self.inventory (maybe with an inventory translation)
https://github.com/SatelliteQE/broker/blob/master/broker/providers/ansible_tower.py#L430

[ogajduse]

Based on the priorities I have now, I can not dedicate more time to this. Feel free to create an issue and we can come back to it later.