my code formatter touched a related test because i was messing around there and added some refresh_from_db() calls just to be sure it was testing what i expected
small config change in the PR template
registered some models for the admin dashboard
Notes
This was happening because of a Django signal's dependency on the Phase, LocalAsset, and PhaseZoneDistribution models. The model PhaseZoneDistribution is subscribed to a post_delete signal that runs after the Phase was deleted (since the phase deletes the LocalAssets, which is the signal the PhaseZoneDistribution is subscribed too — whew!). This caused this integrity error:
django.db.utils.IntegrityError: insert or update on table "asset_dashboard_phasezonedistribution" violates foreign key constraint "asset_dashboard_phas_phase_id_535d6e36_fk_asset_das"
DETAIL: Key (phase_id)=(126) is not present in table "asset_dashboard_phase".
This only happened for a phase with GIS assets. It was happening deep in the Django ORM code (here's a gist with debugger logs if you're curious), so there wasn't a clean way to catch the exception and apply the logic we need.
A story
This fix should cover all of the logical requirements in this hypothetical story:
User creates a Phase. Then user adds some LocalAsset to the phase. Our backend logic should calculate the PhaseZoneDistributions based on the LocalAsset's geographical distribution. This distribution helps with scoring the project.
Then user realizes that they selected the wrong assets. So they delete the assets that are associated with the phase. Whenever the assets are deleted, our backend logic should recalculate the PhaseZoneDistributions (without the deleted asset's geographical area included in the calculation).
Then the user adds more assets and our logic should recalculate the distributions. Then they delete one single asset and our logic should recalculate the distributions. Etc.
Then, for some reason, user needs to delete the entire phase. Since the assets and distributions are associated with the phase, all of those instances should be deleted too.
on_delete=models.CASCADE
Shouldn't this work? This should be the way to clean up the PhaseZoneDistributions.
Yes, but it doesn't work for every case. It works for Phase.objects.delete(), but not when all of the LocalAssets are deleted separately from the phase deletion. Because of this, I'm forcefully deleting the zone distributions whenever all of the local assets are deleted. There's not a good way to set the relationship between LocalAsset and PhaseZoneDistribution in order to take advantage of the cascading deletion.
make note of the "Geographic distance score" on the project detail page
delete the phase. this should work without raising an error.
confirm the geographic distance score went to zero
for good measure, create a new project & phase with assets. go to edit the assets and delete each asset by hand. this should work with no problem. and it should also update the "Geographic distance score"
Overview
Includes:
Notes
This was happening because of a Django signal's dependency on the Phase, LocalAsset, and PhaseZoneDistribution models. The model
PhaseZoneDistributionis subscribed to apost_deletesignal that runs after thePhasewas deleted (since the phase deletes the LocalAssets, which is the signal the PhaseZoneDistribution is subscribed too — whew!). This caused this integrity error:This only happened for a phase with GIS assets. It was happening deep in the Django ORM code (here's a gist with debugger logs if you're curious), so there wasn't a clean way to catch the exception and apply the logic we need.
A story
This fix should cover all of the logical requirements in this hypothetical story:
User creates a Phase. Then user adds some LocalAsset to the phase. Our backend logic should calculate the PhaseZoneDistributions based on the LocalAsset's geographical distribution. This distribution helps with scoring the project.
Then user realizes that they selected the wrong assets. So they delete the assets that are associated with the phase. Whenever the assets are deleted, our backend logic should recalculate the PhaseZoneDistributions (without the deleted asset's geographical area included in the calculation).
Then the user adds more assets and our logic should recalculate the distributions. Then they delete one single asset and our logic should recalculate the distributions. Etc.
Then, for some reason, user needs to delete the entire phase. Since the assets and distributions are associated with the phase, all of those instances should be deleted too.
on_delete=models.CASCADE
Shouldn't this work? This should be the way to clean up the PhaseZoneDistributions.
Yes, but it doesn't work for every case. It works for Phase.objects.delete(), but not when all of the LocalAssets are deleted separately from the phase deletion. Because of this, I'm forcefully deleting the zone distributions whenever all of the local assets are deleted. There's not a good way to set the relationship between LocalAsset and PhaseZoneDistribution in order to take advantage of the cascading deletion.
Testing Instructions