oslo.db/oslo_db/sqlalchemy/compat/utils.py
Mike Bayer c4843bcf14 Workaround non-compatible type.adapt() for SQLAlchemy < 1.1
The ndb change that makes use of String.adapt() to produce a new
object breaks on SQLAlchemy < 1.1 because adapt() there does
not allow for kwargs to override those already
present in the type.

Change-Id: I8cc79dc9bebcb3cb3accf76559bc969c2dae7ed9
2017-08-10 17:23:59 -04:00

70 lines
2.4 KiB
Python

# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import re
import sqlalchemy
SQLA_VERSION = tuple(
int(num) if re.match(r'^\d+$', num) else num
for num in sqlalchemy.__version__.split(".")
)
sqla_110 = SQLA_VERSION >= (1, 1, 0)
sqla_100 = SQLA_VERSION >= (1, 0, 0)
sqla_097 = SQLA_VERSION >= (0, 9, 7)
sqla_094 = SQLA_VERSION >= (0, 9, 4)
sqla_090 = SQLA_VERSION >= (0, 9, 0)
sqla_08 = SQLA_VERSION >= (0, 8)
def get_postgresql_enums(conn):
"""Return a list of ENUM type names on a Postgresql backend.
For SQLAlchemy 0.9 and lower, makes use of the semi-private
_load_enums() method of the Postgresql dialect. In SQLAlchemy
1.0 this feature is supported using get_enums().
This function may only be called when the given connection
is against the Postgresql backend. It will fail for other
kinds of backends.
"""
if sqla_100:
return [e['name'] for e in sqlalchemy.inspect(conn).get_enums()]
else:
return conn.dialect._load_enums(conn).keys()
def adapt_type_object(type_object, target_class, *args, **kw):
"""Call the adapt() method on a type.
For SQLAlchemy 1.0, runs a local version of constructor_copy() that
allows keyword arguments to be overridden.
See https://github.com/zzzeek/sqlalchemy/commit/\
ceeb033054f09db3eccbde3fad1941ec42919a54
"""
if sqla_110:
return type_object.adapt(target_class, *args, **kw)
else:
# NOTE(zzzeek): this only works for basic types, won't work for
# schema types like Enum, Boolean
# NOTE(zzzeek): this code can be removed once requirements
# are at SQLAlchemy >= 1.1
names = sqlalchemy.util.get_cls_kwargs(target_class)
kw.update(
(k, type_object.__dict__[k]) for k in names.difference(kw)
if k in type_object.__dict__)
return target_class(*args, **kw)