def test_sqlite_product_fetch_metadata_none_if_not_exists(tmp_directory):
tmp = Path(tmp_directory)
conn = SQLAlchemyClient('sqlite:///{}'.format(tmp / "database.db"))
numbers = SQLiteRelation((None, 'numbers', 'table'), conn)
numbers.render({})
assert numbers.fetch_metadata() is None
def test_sqlite_product_fetch_metadata_none_if_empty_metadata(tmp_directory):
tmp = Path(tmp_directory)
conn = SQLAlchemyClient('sqlite:///{}'.format(tmp / "database.db"))
df = pd.DataFrame({'a': np.arange(0, 100), 'b': np.arange(100, 200)})
df.to_sql('numbers', conn.engine)
numbers = SQLiteRelation((None, 'numbers', 'table'), conn)
numbers.render({})
assert numbers.fetch_metadata() is None
def test_sqlite_product_save_metadata(tmp_directory):
tmp = Path(tmp_directory)
conn = SQLAlchemyClient('sqlite:///{}'.format(tmp / "database.db"))
numbers = SQLiteRelation((None, 'numbers', 'table'), conn)
numbers.render({})
numbers.metadata['timestamp'] = datetime.now().timestamp()
numbers.metadata['stored_source_code'] = 'some code'
numbers.save_metadata()
fetched = numbers.fetch_metadata()
assert fetched == numbers.metadata
