init: Point alembic to migrate_repo folder in installed Rucio package

[ftorradeflot]

fix #460

[labkode]

Hi @ftorradeflot, we got hit by this bug in a few of our clusters (after more than 12 months running without issues ..._), so it came as a surprise when we couldn't run the migrations because of the missing info in the DB.

Is there a reason to remove the alembic -c /opt/rucio/etc/alembic.ini upgrade head from the instructions?

[ftorradeflot]

Hi @ftorradeflot, we got hit by this bug in a few of our clusters (after more than 12 months running without issues ..._), so it came as a surprise when we couldn't run the migrations because of the missing info in the DB.

Is there a reason to remove the alembic -c /opt/rucio/etc/alembic.ini upgrade head from the instructions?

I did this I while ago and I don't fully remember.

I think the goal was to fix the initialization of the DB to include the alembic version hash. If you are using the init container to trigger automated DB upgrades then you should patch the executable. We are doing it, but according to the docs, it is not recommended to automate DB upgrades.

I doesn't seem to make sense to run both the upgrade and the bootstrap. I don't know ... it may be harmless and we could include both so that the init container can be used for initialization and upgrade without the need for changes. This should be tested.

We could also create a new (nearly identical) upgrade docker image or include a switch in the docker entrypoint to differentiate between init and upgrade.