sqlalchemy >= 1.4 breaks the cleanup cli

[david-caro]

We are getting the following error after upgrading sqlalchemy:

# backy2 cleanup
    INFO: [backy2.logging] $ /usr/bin/backy2 cleanup
    INFO: [backy2.logging] Deleting false positives...
/usr/lib/python3/dist-packages/backy2/meta_backends/sql.py:569: SAWarning: Coercing Subquery object into a select() for use in IN(); please pass a select() construct explicitly
  self.session.query(DeletedBlock.uid).filter(DeletedBlock.uid.in_(self.session.query(Block.uid).distinct(Block.uid).filter(Block.uid.isnot(None)).subquery())).filter(DeletedBlock.time < (inttime() - dt)).delete(synchronize_session=False)
   ERROR: [backy2.logging] subject table for an INSERT, UPDATE or DELETE expected, got Column('uid', String(length=32), table=<deleted_blocks>).
   ERROR: [backy2.logging] Backy failed.


# python3 -c 'import sqlalchemy; print(sqlalchemy.__version__)'
1.4.23

Version 1.4 introduced some extra restrictions to the old api, and a whole new api, and those seem to be breaking that specific contstruct.

[SinisterCrayon]

Anyone else having this same problem, I can confirm the patch @david-caro posted fixes the issue.