pydbantic
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codemation
Foreign Key prevents tables from updating
class User(DataBaseModel):
uuid: str = PrimaryKey(default=generate_uuid)
class Step(DataBaseModel):
"""
A step model, for the database
Links to an owner
"""
uuid: int = PrimaryKey(autoincrement=True)
user_uuid: str = ForeignKey(User, "uuid")
num_steps: int
start_ts: int
end_ts: int
Setup works fine the first time.
After adding one field to User, it fails
class User(DataBaseModel):
uuid: str = PrimaryKey(default=generate_uuid)
password: str | None = None
File "test_proj/.venv/lib/python3.11/site-packages/starlette/routing.py", line 677, in lifespan
async with self.lifespan_context(app) as maybe_state:
File "test_proj/.venv/lib/python3.11/site-packages/starlette/routing.py", line 566, in __aenter__
await self._router.startup()
File "test_proj/.venv/lib/python3.11/site-packages/starlette/routing.py", line 654, in startup
await handler()
File "test_proj/main.py", line 38, in db_setup
await setup_database()
File "test_proj/xeal_api/db.py", line 18, in setup_database
await Database.create(DATABASE_URL, tables=TABLES)
File "test_proj/.venv/lib/python3.11/site-packages/pydbantic/database.py", line 676, in _migrate
await self.compare_tables_and_migrate()
File "test_proj/.venv/lib/python3.11/site-packages/pydbantic/database.py", line 458, in compare_tables_and_migrate
old_table = sqlalchemy.Table(
^^^^^^^^^^^^^^^^^
File "<string>", line 2, in __new__
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/util/deprecations.py", line 309, in warned
return fn(*args, **kwargs)
^^^^^^^^^^^^^^^^^^^
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/sql/schema.py", line 606, in __new__
with util.safe_reraise():
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/util/langhelpers.py", line 70, in __exit__
compat.raise_(
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/util/compat.py", line 207, in raise_
raise exception
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/sql/schema.py", line 602, in __new__
table._init(name, metadata, *args, **kw)
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/sql/schema.py", line 688, in _init
self._init_items(
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/sql/schema.py", line 135, in _init_items
spwd(self, **kw)
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/sql/base.py", line 1046, in _set_parent_with_dispatch
self._set_parent(parent, **kw)
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/sql/schema.py", line 1854, in _set_parent
self._setup_on_memoized_fks(lambda fk: fk._set_remote_table(table))
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/sql/schema.py", line 1873, in _setup_on_memoized_fks
fn(fk)
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/sql/schema.py", line 1854, in <lambda>
self._setup_on_memoized_fks(lambda fk: fk._set_remote_table(table))
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/sql/schema.py", line 2449, in _set_remote_table
self._link_to_col_by_colstring(parenttable, table, colname)
File "test_proj/.venv/lib/python3.11/site-packages/sqlalchemy/sql/schema.py", line 2341, in _link_to_col_by_colstring
assert self.constraint._referred_table is table
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError
This only fails with ForeignKey. Using
class Step(DataBaseModel):
"""
A step model, for the database
Links to an owner
"""
uuid: int = PrimaryKey(autoincrement=True)
user_uuid: User
num_steps: int
start_ts: int
end_ts: int
works perfectly fine. I want to eventually use an index on user_uuid / start_ts hence the want for Foreign key, rather than user_uuid: User, which generates an intermediary table.
@alex-ong what DB did you use to reproduce this behavior?
Just FYI For more granular control, such as Indexes / constraints, it could be worth while to consider using pydbantic with alembic
