Fix attribute error when saving mod that was in deleted modpack

KerbalStuff/objects.py

@@ -274,12 +274,12 @@ def __repr__(self) -> str:
 class ModListItem(Base):  # type: ignore
     __tablename__ = 'modlistitem'
     id = Column(Integer, primary_key=True)
-    mod_id = Column(Integer, ForeignKey('mod.id'))
-    mod = relationship('Mod', backref='mod_list_items')
-    mod_list_id = Column(Integer, ForeignKey('modlist.id'))
+    mod_id = Column(Integer, ForeignKey('mod.id', ondelete='CASCADE'), nullable=False)
+    mod = relationship('Mod', backref=backref('mod_list_items', passive_deletes=True))
+    mod_list_id = Column(Integer, ForeignKey('modlist.id', ondelete='CASCADE'), nullable=False)
     mod_list = relationship('ModList',
-                            backref=backref('mods', order_by="asc(ModListItem.sort_index)"))
-    sort_index = Column(Integer, default=0)
+                            backref=backref('mods', passive_deletes=True, order_by="asc(ModListItem.sort_index)"))
+    sort_index = Column(Integer, default=0, nullable=False)
 
     def __repr__(self) -> str:
         return '<ModListItem %r %r>' % (self.mod_id, self.mod_list_id)

alembic/versions/2021_07_30_16_16_44-1cbfc1acd83d.py

@@ -0,0 +1,40 @@
+"""Make most of modlistitem non-nullable
+
+Revision ID: 1cbfc1acd83d
+Revises: 833ba1ee8c72
+Create Date: 2021-07-30 16:16:44
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '1cbfc1acd83d'
+down_revision = '833ba1ee8c72'
+
+from alembic import op
+import sqlalchemy as sa
+
+
+def upgrade() -> None:
+    # Remove broken rows
+    op.execute("DELETE FROM modlistitem WHERE mod_id is NULL OR mod_list_id is NULL OR sort_index is NULL")
+
+    # Make most of the columns non-nullable
+    op.alter_column('modlistitem', 'mod_id', existing_type=sa.INTEGER(), nullable=False)
+    op.alter_column('modlistitem', 'mod_list_id', existing_type=sa.INTEGER(), nullable=False)
+    op.alter_column('modlistitem', 'sort_index', existing_type=sa.INTEGER(), nullable=False)
+
+    # Cascade deletion for the mod and mod list
+    op.drop_constraint('modlistitem_mod_list_id_fkey', 'modlistitem', type_='foreignkey')
+    op.drop_constraint('modlistitem_mod_id_fkey', 'modlistitem', type_='foreignkey')
+    op.create_foreign_key('modlistitem_mod_list_id_fkey', 'modlistitem', 'modlist', ['mod_list_id'], ['id'], ondelete='CASCADE')
+    op.create_foreign_key('modlistitem_mod_id_fkey', 'modlistitem', 'mod', ['mod_id'], ['id'], ondelete='CASCADE')
+
+
+def downgrade() -> None:
+    op.drop_constraint('modlistitem_mod_id_fkey', 'modlistitem', type_='foreignkey')
+    op.drop_constraint('modlistitem_mod_list_id_fkey', 'modlistitem', type_='foreignkey')
+    op.create_foreign_key('modlistitem_mod_id_fkey', 'modlistitem', 'mod', ['mod_id'], ['id'])
+    op.create_foreign_key('modlistitem_mod_list_id_fkey', 'modlistitem', 'modlist', ['mod_list_id'], ['id'])
+    op.alter_column('modlistitem', 'sort_index', existing_type=sa.INTEGER(), nullable=True)
+    op.alter_column('modlistitem', 'mod_list_id', existing_type=sa.INTEGER(), nullable=True)
+    op.alter_column('modlistitem', 'mod_id', existing_type=sa.INTEGER(), nullable=True)