openstack/tacker
Code Issues Proposed changes

Use oslo db for db access

Browse Source 
Change-Id: I5f33d747543b5ba936b8ac46e68bf43b1792e231
Partial-bug: #1552282
This commit is contained in:
gong yong sheng 2016-06-03 15:15:22 +08:00
parent 70190b66ba
commit 2a257882fb
17 changed files with 22 additions and 2426 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
requirements.txt
View File

@ -25,6 +25,7 @@ six>=1.9.0 # MIT
stevedore>=1.10.0 # Apache-2.0
oslo.concurrency>=3.8.0 # Apache-2.0
oslo.config>=3.10.0 # Apache-2.0
oslo.db>=4.1.0 # Apache-2.0
oslo.log>=1.14.0 # Apache-2.0
oslo.messaging>=4.5.0 # Apache-2.0
oslo.rootwrap>=2.0.0 # Apache-2.0

20
tacker/common/config.py
View File

@ -20,12 +20,12 @@ Routines for configuring Tacker
import os
from oslo_config import cfg
from oslo_db import options as db_options
from oslo_log import log as logging
import oslo_messaging
from paste import deploy
from tacker.common import utils
from tacker.openstack.common.db import options as db_options
from tacker import version
@ -95,12 +95,18 @@ cfg.CONF.register_cli_opts(core_cli_opts)
# Ensure that the control exchange is set correctly
oslo_messaging.set_transport_defaults(control_exchange='tacker')
_SQL_CONNECTION_DEFAULT = 'sqlite://'
# Update the default QueuePool parameters. These can be tweaked by the
# configuration variables - max_pool_size, max_overflow and pool_timeout
db_options.set_defaults(sql_connection=_SQL_CONNECTION_DEFAULT,
sqlite_db='', max_pool_size=10,
max_overflow=20, pool_timeout=10)
def set_db_defaults():
# Update the default QueuePool parameters. These can be tweaked by the
# conf variables - max_pool_size, max_overflow and pool_timeout
db_options.set_defaults(
cfg.CONF,
connection='sqlite://',
sqlite_db='', max_pool_size=10,
max_overflow=20, pool_timeout=10)
set_db_defaults()
def init(args, **kwargs):

47
tacker/db/api.py
View File

@ -14,17 +14,13 @@
# under the License.
from oslo_config import cfg
from oslo_db.sqlalchemy import enginefacade
from oslo_log import log as logging
import sqlalchemy as sql
from tacker.db import model_base
from tacker.openstack.common.db.sqlalchemy import session
LOG = logging.getLogger(__name__)
cfg.CONF.import_opt('connection',
'tacker.openstack.common.db.options',
group='database')
context_manager = enginefacade.transaction_context()
_FACADE = None
@ -33,25 +29,12 @@ def _create_facade_lazily():
global _FACADE
if _FACADE is None:
_FACADE = session.EngineFacade.from_config(
cfg.CONF.database.connection, cfg.CONF, sqlite_fk=True)
context_manager.configure(sqlite_fk=True, **cfg.CONF.database)
_FACADE = context_manager._factory.get_legacy_facade()
return _FACADE
def configure_db():
"""Configure database.
Establish the database, create an engine if needed, and register
the models.
"""
register_models()
def clear_db(base=model_base.BASE):
unregister_models(base)
def get_engine():
"""Helper method to grab engine."""
facade = _create_facade_lazily()
@ -63,25 +46,3 @@ def get_session(autocommit=True, expire_on_commit=False):
facade = _create_facade_lazily()
return facade.get_session(autocommit=autocommit,
expire_on_commit=expire_on_commit)
def register_models(base=model_base.BASE):
"""Register Models and create properties."""
try:
facade = _create_facade_lazily()
engine = facade.get_engine()
base.metadata.create_all(engine)
except sql.exc.OperationalError as e:
LOG.info(_("Database registration exception: %s"), e)
return False
return True
def unregister_models(base=model_base.BASE):
"""Unregister Models, useful clearing out data before testing."""
try:
facade = _create_facade_lazily()
engine = facade.get_engine()
base.metadata.drop_all(engine)
except Exception:
LOG.exception(_("Database exception"))

3
tacker/db/model_base.py
View File

@ -13,11 +13,10 @@
# See the License for the specific language governing permissions and
# limitations under the License.
from oslo_db.sqlalchemy import models
from sqlalchemy.ext import declarative
from sqlalchemy import orm
from tacker.openstack.common.db.sqlalchemy import models
class TackerBase(models.ModelBase):
"""Base class for Tacker Models."""

4
tacker/db/nfvo/nfvo_db.py
View File

@ -16,19 +16,18 @@
import uuid
from oslo_db import exception
import sqlalchemy as sa
from sqlalchemy import orm
from sqlalchemy.orm import exc as orm_exc
from sqlalchemy import sql
from tacker.db import api as tdbapi
from tacker.db import db_base
from tacker.db import model_base
from tacker.db import models_v1
from tacker.db.vm import vm_db
from tacker.extensions import nfvo
from tacker import manager
from tacker.openstack.common.db import exception
from tacker.openstack.common import uuidutils
@ -64,7 +63,6 @@ class VimAuth(model_base.BASE, models_v1.HasId):
class NfvoPluginDb(nfvo.NFVOPluginBase, db_base.CommonDbMixin):
def __init__(self):
tdbapi.register_models()
super(NfvoPluginDb, self).__init__()
@property

2
tacker/db/vm/vm_db.py
View File

@ -23,7 +23,6 @@ from sqlalchemy.orm import exc as orm_exc
from tacker.api.v1 import attributes
from tacker import context as t_context
from tacker.db import api as qdbapi
from tacker.db import db_base
from tacker.db import model_base
from tacker.db import models_v1
@ -148,7 +147,6 @@ class VNFMPluginDb(vnfm.VNFMPluginBase, db_base.CommonDbMixin):
return subnet['network_id']
def __init__(self):
qdbapi.register_models()
super(VNFMPluginDb, self).__init__()
def _get_resource(self, context, model, id):

0
tacker/openstack/common/db/__init__.py
View File

162
tacker/openstack/common/db/api.py
View File

@ -1,162 +0,0 @@
# Copyright (c) 2013 Rackspace Hosting
# All Rights Reserved.
#
# 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.
"""Multiple DB API backend support.
A DB backend module should implement a method named 'get_backend' which
takes no arguments. The method can return any object that implements DB
API methods.
"""
import functools
import logging
import threading
import time
from tacker.openstack.common.db import exception
from tacker.openstack.common.gettextutils import _LE
from tacker.openstack.common import importutils
LOG = logging.getLogger(__name__)
def safe_for_db_retry(f):
"""Enable db-retry for decorated function, if config option enabled."""
f.__dict__['enable_retry'] = True
return f
class wrap_db_retry(object):
"""Retry db.api methods, if DBConnectionError() raised
Retry decorated db.api methods. If we enabled `use_db_reconnect`
in config, this decorator will be applied to all db.api functions,
marked with @safe_for_db_retry decorator.
Decorator catchs DBConnectionError() and retries function in a
loop until it succeeds, or until maximum retries count will be reached.
"""
def __init__(self, retry_interval, max_retries, inc_retry_interval,
max_retry_interval):
super(wrap_db_retry, self).__init__()
self.retry_interval = retry_interval
self.max_retries = max_retries
self.inc_retry_interval = inc_retry_interval
self.max_retry_interval = max_retry_interval
def __call__(self, f):
@functools.wraps(f)
def wrapper(*args, **kwargs):
next_interval = self.retry_interval
remaining = self.max_retries
while True:
try:
return f(*args, **kwargs)
except exception.DBConnectionError as e:
if remaining == 0:
LOG.exception(_LE('DB exceeded retry limit.'))
raise exception.DBError(e)
if remaining != -1:
remaining -= 1
LOG.exception(_LE('DB connection error.'))
# NOTE(vsergeyev): We are using patched time module, so
# this effectively yields the execution
# context to another green thread.
time.sleep(next_interval)
if self.inc_retry_interval:
next_interval = min(
next_interval * 2,
self.max_retry_interval
)
return wrapper
class DBAPI(object):
def __init__(self, backend_name, backend_mapping=None, lazy=False,
**kwargs):
"""Initialize the chosen DB API backend.
:param backend_name: name of the backend to load
:type backend_name: str
:param backend_mapping: backend name -> module/class to load mapping
:type backend_mapping: dict
:param lazy: load the DB backend lazily on the first DB API method call
:type lazy: bool
Keyword arguments:
:keyword use_db_reconnect: retry DB transactions on disconnect or not
:type use_db_reconnect: bool
:keyword retry_interval: seconds between transaction retries
:type retry_interval: int
:keyword inc_retry_interval: increase retry interval or not
:type inc_retry_interval: bool
:keyword max_retry_interval: max interval value between retries
:type max_retry_interval: int
:keyword max_retries: max number of retries before an error is raised
:type max_retries: int
"""
self._backend = None
self._backend_name = backend_name
self._backend_mapping = backend_mapping or {}
self._lock = threading.Lock()
if not lazy:
self._load_backend()
self.use_db_reconnect = kwargs.get('use_db_reconnect', False)
self.retry_interval = kwargs.get('retry_interval', 1)
self.inc_retry_interval = kwargs.get('inc_retry_interval', True)
self.max_retry_interval = kwargs.get('max_retry_interval', 10)
self.max_retries = kwargs.get('max_retries', 20)
def _load_backend(self):
with self._lock:
if not self._backend:
# Import the untranslated name if we don't have a mapping
backend_path = self._backend_mapping.get(self._backend_name,
self._backend_name)
backend_mod = importutils.import_module(backend_path)
self._backend = backend_mod.get_backend()
def __getattr__(self, key):
if not self._backend:
self._load_backend()
attr = getattr(self._backend, key)
if not hasattr(attr, '__call__'):
return attr
# NOTE(vsergeyev): If `use_db_reconnect` option is set to True, retry
# DB API methods, decorated with @safe_for_db_retry
# on disconnect.
if self.use_db_reconnect and hasattr(attr, 'enable_retry'):
attr = wrap_db_retry(
retry_interval=self.retry_interval,
max_retries=self.max_retries,
inc_retry_interval=self.inc_retry_interval,
max_retry_interval=self.max_retry_interval)(attr)
return attr

56
tacker/openstack/common/db/exception.py
View File

@ -1,56 +0,0 @@
# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# All Rights Reserved.
#
# 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.
"""DB related custom exceptions."""
import six
from tacker.openstack.common.gettextutils import _
class DBError(Exception):
"""Wraps an implementation specific exception."""
def __init__(self, inner_exception=None):
self.inner_exception = inner_exception
super(DBError, self).__init__(six.text_type(inner_exception))
class DBDuplicateEntry(DBError):
"""Wraps an implementation specific exception."""
def __init__(self, columns=None, inner_exception=None):
self.columns = columns if columns else []
super(DBDuplicateEntry, self).__init__(inner_exception)
class DBDeadlock(DBError):
def __init__(self, inner_exception=None):
super(DBDeadlock, self).__init__(inner_exception)
class DBInvalidUnicodeParameter(Exception):
message = _("Invalid Parameter: "
"Unicode is not supported by the current database.")
class DbMigrationError(DBError):
"""Wraps migration specific exception."""
def __init__(self, message=None):
super(DbMigrationError, self).__init__(message)
class DBConnectionError(DBError):
"""Wraps connection specific exception."""
pass

171
tacker/openstack/common/db/options.py
View File

@ -1,171 +0,0 @@
# 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 copy
from oslo_config import cfg
database_opts = [
cfg.StrOpt('sqlite_db',
deprecated_group='DEFAULT',
default='tacker.sqlite',
help='The file name to use with SQLite'),
cfg.BoolOpt('sqlite_synchronous',
deprecated_group='DEFAULT',
default=True,
help='If True, SQLite uses synchronous mode'),
cfg.StrOpt('backend',
default='sqlalchemy',
deprecated_name='db_backend',
deprecated_group='DEFAULT',
help='The backend to use for db'),
cfg.StrOpt('connection',
help='The SQLAlchemy connection string used to connect to the '
'database',
secret=True,
deprecated_opts=[cfg.DeprecatedOpt('sql_connection',
group='DEFAULT'),
cfg.DeprecatedOpt('sql_connection',
group='DATABASE'),
cfg.DeprecatedOpt('connection',
group='sql'), ]),
cfg.StrOpt('mysql_sql_mode',
default='TRADITIONAL',
help='The SQL mode to be used for MySQL sessions. '
'This option, including the default, overrides any '
'server-set SQL mode. To use whatever SQL mode '
'is set by the server configuration, '
'set this to no value. Example: mysql_sql_mode='),
cfg.IntOpt('idle_timeout',
default=3600,
deprecated_opts=[cfg.DeprecatedOpt('sql_idle_timeout',
group='DEFAULT'),
cfg.DeprecatedOpt('sql_idle_timeout',
group='DATABASE'),
cfg.DeprecatedOpt('idle_timeout',
group='sql')],
help='Timeout before idle sql connections are reaped'),
cfg.IntOpt('min_pool_size',
default=1,
deprecated_opts=[cfg.DeprecatedOpt('sql_min_pool_size',
group='DEFAULT'),
cfg.DeprecatedOpt('sql_min_pool_size',
group='DATABASE')],
help='Minimum number of SQL connections to keep open in a '
'pool'),
cfg.IntOpt('max_pool_size',
default=None,
deprecated_opts=[cfg.DeprecatedOpt('sql_max_pool_size',
group='DEFAULT'),
cfg.DeprecatedOpt('sql_max_pool_size',
group='DATABASE')],
help='Maximum number of SQL connections to keep open in a '
'pool'),
cfg.IntOpt('max_retries',
default=10,
deprecated_opts=[cfg.DeprecatedOpt('sql_max_retries',
group='DEFAULT'),
cfg.DeprecatedOpt('sql_max_retries',
group='DATABASE')],
help='Maximum db connection retries during startup. '
'(setting -1 implies an infinite retry count)'),
cfg.IntOpt('retry_interval',
default=10,
deprecated_opts=[cfg.DeprecatedOpt('sql_retry_interval',
group='DEFAULT'),
cfg.DeprecatedOpt('reconnect_interval',
group='DATABASE')],
help='Interval between retries of opening a sql connection'),
cfg.IntOpt('max_overflow',
default=None,
deprecated_opts=[cfg.DeprecatedOpt('sql_max_overflow',
group='DEFAULT'),
cfg.DeprecatedOpt('sqlalchemy_max_overflow',
group='DATABASE')],
help='If set, use this value for max_overflow with sqlalchemy'),
cfg.IntOpt('connection_debug',
default=0,
deprecated_opts=[cfg.DeprecatedOpt('sql_connection_debug',
group='DEFAULT')],
help='Verbosity of SQL debugging information. 0=None, '
'100=Everything'),
cfg.BoolOpt('connection_trace',
default=False,
deprecated_opts=[cfg.DeprecatedOpt('sql_connection_trace',
group='DEFAULT')],
help='Add python stack traces to SQL as comment strings'),
cfg.IntOpt('pool_timeout',
default=None,
deprecated_opts=[cfg.DeprecatedOpt('sqlalchemy_pool_timeout',
group='DATABASE')],
help='If set, use this value for pool_timeout with sqlalchemy'),
cfg.BoolOpt('use_db_reconnect',
default=False,
help='Enable the experimental use of database reconnect '
'on connection lost'),
cfg.IntOpt('db_retry_interval',
default=1,
help='seconds between db connection retries'),
cfg.BoolOpt('db_inc_retry_interval',
default=True,
help='Whether to increase interval between db connection '
'retries, up to db_max_retry_interval'),
cfg.IntOpt('db_max_retry_interval',
default=10,
help='max seconds between db connection retries, if '
'db_inc_retry_interval is enabled'),
cfg.IntOpt('db_max_retries',
default=20,
help='maximum db connection retries before error is raised. '
'(setting -1 implies an infinite retry count)'),
]
CONF = cfg.CONF
CONF.register_opts(database_opts, 'database')
def set_defaults(sql_connection, sqlite_db, max_pool_size=None,
max_overflow=None, pool_timeout=None):
"""Set defaults for configuration variables."""
cfg.set_defaults(database_opts,
connection=sql_connection,
sqlite_db=sqlite_db)
# Update the QueuePool defaults
if max_pool_size is not None:
cfg.set_defaults(database_opts,
max_pool_size=max_pool_size)
if max_overflow is not None:
cfg.set_defaults(database_opts,
max_overflow=max_overflow)
if pool_timeout is not None:
cfg.set_defaults(database_opts,
pool_timeout=pool_timeout)
def list_opts():
"""Returns a list of oslo_config options available in the library.
The returned list includes all oslo_config options which may be registered
at runtime by the library.
Each element of the list is a tuple. The first element is the name of the
group under which the list of elements in the second element will be
registered. A group name of None corresponds to the [DEFAULT] group in
config files.
The purpose of this is to allow tools like the Oslo sample config file
generator to discover the options exposed to users by this library.
:returns: a list of (group_name, opts) tuples
"""
return [('database', copy.deepcopy(database_opts))]

0
tacker/openstack/common/db/sqlalchemy/__init__.py
View File

119
tacker/openstack/common/db/sqlalchemy/models.py
View File

@ -1,119 +0,0 @@
# Copyright (c) 2011 X.commerce, a business unit of eBay Inc.
# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# Copyright 2011 Piston Cloud Computing, Inc.
# Copyright 2012 Cloudscaling Group, Inc.
# All Rights Reserved.
#
# 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.
"""
SQLAlchemy models.
"""
import six
from sqlalchemy import Column, Integer
from sqlalchemy import DateTime
from sqlalchemy.orm import object_mapper
from tacker.openstack.common import timeutils
class ModelBase(six.Iterator):
"""Base class for models."""
__table_initialized__ = False
def save(self, session):
"""Save this object."""
# NOTE(boris-42): This part of code should be look like:
# session.add(self)
# session.flush()
# But there is a bug in sqlalchemy and eventlet that
# raises NoneType exception if there is no running
# transaction and rollback is called. As long as
# sqlalchemy has this bug we have to create transaction
# explicitly.
with session.begin(subtransactions=True):
session.add(self)
session.flush()
def __setitem__(self, key, value):
setattr(self, key, value)
def __getitem__(self, key):
return getattr(self, key)
def get(self, key, default=None):
return getattr(self, key, default)
@property
def _extra_keys(self):
"""Specifies custom fields
Subclasses can override this property to return a list
of custom fields that should be included in their dict
representation.
For reference check tests/db/sqlalchemy/test_models.py
"""
return []
def __iter__(self):
columns = dict(object_mapper(self).columns).keys()
# NOTE(russellb): Allow models to specify other keys that can be looked
# up, beyond the actual db columns. An example would be the 'name'
# property for an Instance.
columns.extend(self._extra_keys)
self._i = iter(columns)
return self
# In Python 3, __next__() has replaced next().
def __next__(self):
n = six.advance_iterator(self._i)
return n, getattr(self, n)
def next(self):
return self.__next__()
def update(self, values):
"""Make the model object behave like a dict."""
for k, v in six.iteritems(values):
setattr(self, k, v)
def iteritems(self):
"""Make the model object behave like a dict.
Includes attributes from joins.
"""
local = dict(self)
joined = dict([(k, v) for k, v in six.iteritems(self.__dict__)
if not k[0] == '_'])
local.update(joined)
return six.iteritems(local)
class TimestampMixin(object):
created_at = Column(DateTime, default=lambda: timeutils.utcnow())
updated_at = Column(DateTime, onupdate=lambda: timeutils.utcnow())
class SoftDeleteMixin(object):
deleted_at = Column(DateTime)
deleted = Column(Integer, default=0)
def soft_delete(self, session):
"""Mark this object as deleted."""
self.deleted = self.id
self.deleted_at = timeutils.utcnow()
self.save(session=session)

157
tacker/openstack/common/db/sqlalchemy/provision.py
View File

@ -1,157 +0,0 @@
# Copyright 2013 Mirantis.inc
# All Rights Reserved.
#
# 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.
"""Provision test environment for specific DB backends"""
import argparse
import logging
import os
import random
import string
from six import moves
import sqlalchemy
from tacker.openstack.common.db import exception as exc
LOG = logging.getLogger(__name__)
def get_engine(uri):
"""Engine creation
Call the function without arguments to get admin connection. Admin
connection required to create temporary user and database for each
particular test. Otherwise use existing connection to recreate connection
to the temporary database.
"""
return sqlalchemy.create_engine(uri, poolclass=sqlalchemy.pool.NullPool)
def _execute_sql(engine, sql, driver):
"""Initialize connection, execute sql query and close it."""
try:
with engine.connect() as conn:
if driver == 'postgresql':
conn.connection.set_isolation_level(0)
for s in sql:
conn.execute(s)
except sqlalchemy.exc.OperationalError:
msg = ('%s does not match database admin '
'credentials or database does not exist.')
LOG.exception(msg % engine.url)
raise exc.DBConnectionError(msg % engine.url)
def create_database(engine):
"""Provide temporary user and database for each particular test."""
driver = engine.name
auth = {
'database': ''.join(random.choice(string.ascii_lowercase)
for i in moves.range(10)),
'user': engine.url.username,
'passwd': engine.url.password,
}
sqls = [
"drop database if exists %(database)s;",
"create database %(database)s;"
]
if driver == 'sqlite':
return 'sqlite:////tmp/%s' % auth['database']
elif driver in ['mysql', 'postgresql']:
sql_query = map(lambda x: x % auth, sqls)
_execute_sql(engine, sql_query, driver)
else:
raise ValueError('Unsupported RDBMS %s' % driver)
params = auth.copy()
params['backend'] = driver
return "%(backend)s://%(user)s:%(passwd)s@localhost/%(database)s" % params
def drop_database(admin_engine, current_uri):
"""Drop temporary database and user after each particular test."""
engine = get_engine(current_uri)
driver = engine.name
auth = {'database': engine.url.database, 'user': engine.url.username}
if driver == 'sqlite':
try:
os.remove(auth['database'])
except OSError:
pass
elif driver in ['mysql', 'postgresql']:
sql = "drop database if exists %(database)s;"
_execute_sql(admin_engine, [sql % auth], driver)
else:
raise ValueError('Unsupported RDBMS %s' % driver)
def main():
"""Controller to handle commands
::create: Create test user and database with random names.
::drop: Drop user and database created by previous command.
"""
parser = argparse.ArgumentParser(
description='Controller to handle database creation and dropping'
' commands.',
epilog='Under normal circumstances is not used directly.'
' Used in .testr.conf to automate test database creation'
' and dropping processes.')
subparsers = parser.add_subparsers(
help='Subcommands to manipulate temporary test databases.')
create = subparsers.add_parser(
'create',
help='Create temporary test '
'databases and users.')
create.set_defaults(which='create')
create.add_argument(
'instances_count',
type=int,
help='Number of databases to create.')
drop = subparsers.add_parser(
'drop',
help='Drop temporary test databases and users.')
drop.set_defaults(which='drop')
drop.add_argument(
'instances',
nargs='+',
help='List of databases uri to be dropped.')
args = parser.parse_args()
connection_string = os.getenv('OS_TEST_DBAPI_ADMIN_CONNECTION',
'sqlite://')
engine = get_engine(connection_string)
which = args.which
if which == "create":
for i in range(int(args.instances_count)):
print(create_database(engine))
elif which == "drop":
for db in args.instances:
drop_database(engine, db)
if __name__ == "__main__":
main()

904
tacker/openstack/common/db/sqlalchemy/session.py
View File

@ -1,904 +0,0 @@
# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# All Rights Reserved.
#
# 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.
"""Session Handling for SQLAlchemy backend.
Recommended ways to use sessions within this framework:
* Don't use them explicitly; this is like running with ``AUTOCOMMIT=1``.
`model_query()` will implicitly use a session when called without one
supplied. This is the ideal situation because it will allow queries
to be automatically retried if the database connection is interrupted.
.. note:: Automatic retry will be enabled in a future patch.
It is generally fine to issue several queries in a row like this. Even though
they may be run in separate transactions and/or separate sessions, each one
will see the data from the prior calls. If needed, undo- or rollback-like
functionality should be handled at a logical level. For an example, look at
the code around quotas and `reservation_rollback()`.
Examples:
.. code:: python
def get_foo(context, foo):
return (model_query(context, models.Foo).
filter_by(foo=foo).
first())
def update_foo(context, id, newfoo):
(model_query(context, models.Foo).
filter_by(id=id).
update({'foo': newfoo}))
def create_foo(context, values):
foo_ref = models.Foo()
foo_ref.update(values)
foo_ref.save()
return foo_ref
* Within the scope of a single method, keep all the reads and writes within
the context managed by a single session. In this way, the session's
`__exit__` handler will take care of calling `flush()` and `commit()` for
you. If using this approach, you should not explicitly call `flush()` or
`commit()`. Any error within the context of the session will cause the
session to emit a `ROLLBACK`. Database errors like `IntegrityError` will be
raised in `session`'s `__exit__` handler, and any try/except within the
context managed by `session` will not be triggered. And catching other
non-database errors in the session will not trigger the ROLLBACK, so
exception handlers should always be outside the session, unless the
developer wants to do a partial commit on purpose. If the connection is
dropped before this is possible, the database will implicitly roll back the
transaction.
.. note:: Statements in the session scope will not be automatically retried.
If you create models within the session, they need to be added, but you
do not need to call `model.save()`:
.. code:: python
def create_many_foo(context, foos):
session = sessionmaker()
with session.begin():
for foo in foos:
foo_ref = models.Foo()
foo_ref.update(foo)
session.add(foo_ref)
def update_bar(context, foo_id, newbar):
session = sessionmaker()
with session.begin():
foo_ref = (model_query(context, models.Foo, session).
filter_by(id=foo_id).
first())
(model_query(context, models.Bar, session).
filter_by(id=foo_ref['bar_id']).
update({'bar': newbar}))
.. note:: `update_bar` is a trivially simple example of using
``with session.begin``. Whereas `create_many_foo` is a good example of
when a transaction is needed, it is always best to use as few queries as
possible.
The two queries in `update_bar` can be better expressed using a single query
which avoids the need for an explicit transaction. It can be expressed like
so:
.. code:: python
def update_bar(context, foo_id, newbar):
subq = (model_query(context, models.Foo.id).
filter_by(id=foo_id).
limit(1).
subquery())
(model_query(context, models.Bar).
filter_by(id=subq.as_scalar()).
update({'bar': newbar}))
For reference, this emits approximately the following SQL statement:
.. code:: sql
UPDATE bar SET bar = ${newbar}
WHERE id=(SELECT bar_id FROM foo WHERE id = ${foo_id} LIMIT 1);
.. note:: `create_duplicate_foo` is a trivially simple example of catching an
exception while using ``with session.begin``. Here create two duplicate
instances with same primary key, must catch the exception out of context
managed by a single session:
.. code:: python
def create_duplicate_foo(context):
foo1 = models.Foo()
foo2 = models.Foo()
foo1.id = foo2.id = 1
session = sessionmaker()
try:
with session.begin():
session.add(foo1)
session.add(foo2)
except exception.DBDuplicateEntry as e:
handle_error(e)
* Passing an active session between methods. Sessions should only be passed
to private methods. The private method must use a subtransaction; otherwise
SQLAlchemy will throw an error when you call `session.begin()` on an existing
transaction. Public methods should not accept a session parameter and should
not be involved in sessions within the caller's scope.
Note that this incurs more overhead in SQLAlchemy than the above means
due to nesting transactions, and it is not possible to implicitly retry
failed database operations when using this approach.
This also makes code somewhat more difficult to read and debug, because a
single database transaction spans more than one method. Error handling
becomes less clear in this situation. When this is needed for code clarity,
it should be clearly documented.
.. code:: python
def myfunc(foo):
session = sessionmaker()
with session.begin():
# do some database things
bar = _private_func(foo, session)
return bar
def _private_func(foo, session=None):
if not session:
session = sessionmaker()
with session.begin(subtransaction=True):
# do some other database things
return bar
There are some things which it is best to avoid:
* Don't keep a transaction open any longer than necessary.
This means that your ``with session.begin()`` block should be as short
as possible, while still containing all the related calls for that
transaction.
* Avoid ``with_lockmode('UPDATE')`` when possible.
In MySQL/InnoDB, when a ``SELECT ... FOR UPDATE`` query does not match
any rows, it will take a gap-lock. This is a form of write-lock on the
"gap" where no rows exist, and prevents any other writes to that space.
This can effectively prevent any INSERT into a table by locking the gap
at the end of the index. Similar problems will occur if the SELECT FOR UPDATE
has an overly broad WHERE clause, or doesn't properly use an index.
One idea proposed at ODS Fall '12 was to use a normal SELECT to test the
number of rows matching a query, and if only one row is returned,
then issue the SELECT FOR UPDATE.
The better long-term solution is to use
``INSERT .. ON DUPLICATE KEY UPDATE``.
However, this can not be done until the "deleted" columns are removed and
proper UNIQUE constraints are added to the tables.
Enabling soft deletes:
* To use/enable soft-deletes, the `SoftDeleteMixin` must be added
to your model class. For example:
.. code:: python
class NovaBase(models.SoftDeleteMixin, models.ModelBase):
pass
Efficient use of soft deletes:
* There are two possible ways to mark a record as deleted:
`model.soft_delete()` and `query.soft_delete()`.
The `model.soft_delete()` method works with a single already-fetched entry.
`query.soft_delete()` makes only one db request for all entries that
correspond to the query.
* In almost all cases you should use `query.soft_delete()`. Some examples:
.. code:: python
def soft_delete_bar():
count = model_query(BarModel).find(some_condition).soft_delete()
if count == 0:
raise Exception("0 entries were soft deleted")
def complex_soft_delete_with_synchronization_bar(session=None):
if session is None:
session = sessionmaker()
with session.begin(subtransactions=True):
count = (model_query(BarModel).
find(some_condition).
soft_delete(synchronize_session=True))
# Here synchronize_session is required, because we
# don't know what is going on in outer session.
if count == 0:
raise Exception("0 entries were soft deleted")
* There is only one situation where `model.soft_delete()` is appropriate: when
you fetch a single record, work with it, and mark it as deleted in the same
transaction.
.. code:: python
def soft_delete_bar_model():
session = sessionmaker()
with session.begin():
bar_ref = model_query(BarModel).find(some_condition).first()
# Work with bar_ref
bar_ref.soft_delete(session=session)
However, if you need to work with all entries that correspond to query and
then soft delete them you should use the `query.soft_delete()` method:
.. code:: python
def soft_delete_multi_models():
session = sessionmaker()
with session.begin():
query = (model_query(BarModel, session=session).
find(some_condition))
model_refs = query.all()
# Work with model_refs
query.soft_delete(synchronize_session=False)
# synchronize_session=False should be set if there is no outer
# session and these entries are not used after this.
When working with many rows, it is very important to use query.soft_delete,
which issues a single query. Using `model.soft_delete()`, as in the following
example, is very inefficient.
.. code:: python
for bar_ref in bar_refs:
bar_ref.soft_delete(session=session)
# This will produce count(bar_refs) db requests.
"""
import functools
import logging
import re
import time
import six
from sqlalchemy import exc as sqla_exc
from sqlalchemy.interfaces import PoolListener
import sqlalchemy.orm
from sqlalchemy.pool import NullPool, StaticPool
from sqlalchemy.sql.expression import literal_column
from tacker.openstack.common.db import exception
from tacker.openstack.common.gettextutils import _LE, _LW
from tacker.openstack.common import timeutils
LOG = logging.getLogger(__name__)
class SqliteForeignKeysListener(PoolListener):
"""Ensures that the foreign key constraints are enforced in SQLite.
The foreign key constraints are disabled by default in SQLite,
so the foreign key constraints will be enabled here for every
database connection
"""
def connect(self, dbapi_con, con_record):
dbapi_con.execute('pragma foreign_keys=ON')
# note(boris-42): In current versions of DB backends unique constraint
# violation messages follow the structure:
#
# sqlite:
# 1 column - (IntegrityError) column c1 is not unique
# N columns - (IntegrityError) column c1, c2, ..., N are not unique
#
# sqlite since 3.7.16:
# 1 column - (IntegrityError) UNIQUE constraint failed: tbl.k1
#
# N columns - (IntegrityError) UNIQUE constraint failed: tbl.k1, tbl.k2
#
# postgres:
# 1 column - (IntegrityError) duplicate key value violates unique
# constraint "users_c1_key"
# N columns - (IntegrityError) duplicate key value violates unique
# constraint "name_of_our_constraint"
#
# mysql:
# 1 column - (IntegrityError) (1062, "Duplicate entry 'value_of_c1' for key
# 'c1'")
# N columns - (IntegrityError) (1062, "Duplicate entry 'values joined
# with -' for key 'name_of_our_constraint'")
#
# ibm_db_sa:
# N columns - (IntegrityError) SQL0803N One or more values in the INSERT
# statement, UPDATE statement, or foreign key update caused by a
# DELETE statement are not valid because the primary key, unique
# constraint or unique index identified by "2" constrains table
# "NOVA.KEY_PAIRS" from having duplicate values for the index
# key.
_DUP_KEY_RE_DB = {
"sqlite": (re.compile(r"^.*columns?([^)]+)(is|are)\s+not\s+unique$"),
re.compile(r"^.*UNIQUE\s+constraint\s+failed:\s+(.+)$")),
"postgresql": (re.compile(r"^.*duplicate\s+key.*\"([^\"]+)\"\s*\n.*$"),),
"mysql": (re.compile(r"^.*\(1062,.*'([^\']+)'\"\)$"),),
"ibm_db_sa": (re.compile(r"^.*SQL0803N.*$"),),
}
def _raise_if_duplicate_entry_error(integrity_error, engine_name):
"""Raise exception if two entries are duplicated.
In this function will be raised DBDuplicateEntry exception if integrity
error wrap unique constraint violation.
"""
def get_columns_from_uniq_cons_or_name(columns):
# note(vsergeyev): UniqueConstraint name convention: "uniq_t0c10c2"
# where `t` it is table name and columns `c1`, `c2`
# are in UniqueConstraint.
uniqbase = "uniq_"
if not columns.startswith(uniqbase):
if engine_name == "postgresql":
return [columns[columns.index("_") + 1:columns.rindex("_")]]
return [columns]
return columns[len(uniqbase):].split("0")[1:]
if engine_name not in ("ibm_db_sa", "mysql", "sqlite", "postgresql"):
return
# FIXME(johannes): The usage of the .message attribute has been
# deprecated since Python 2.6. However, the exceptions raised by
# SQLAlchemy can differ when using unicode() and accessing .message.
# An audit across all three supported engines will be necessary to
# ensure there are no regressions.
for pattern in _DUP_KEY_RE_DB[engine_name]:
match = pattern.match(integrity_error.message)
if match:
break
else:
return
# NOTE(mriedem): The ibm_db_sa integrity error message doesn't provide the
# columns so we have to omit that from the DBDuplicateEntry error.
columns = ''
if engine_name != 'ibm_db_sa':
columns = match.group(1)
if engine_name == "sqlite":
columns = [c.split('.')[-1] for c in columns.strip().split(", ")]
else:
columns = get_columns_from_uniq_cons_or_name(columns)
raise exception.DBDuplicateEntry(columns, integrity_error)
# NOTE(comstud): In current versions of DB backends, Deadlock violation
# messages follow the structure:
#
# mysql:
# (OperationalError) (1213, 'Deadlock found when trying to get lock; try '
# 'restarting transaction') <query_str> <query_args>
_DEADLOCK_RE_DB = {
"mysql": re.compile(r"^.*\(1213, 'Deadlock.*")
}
def _raise_if_deadlock_error(operational_error, engine_name):
"""Raise exception on deadlock condition.
Raise DBDeadlock exception if OperationalError contains a Deadlock
condition.
"""
re = _DEADLOCK_RE_DB.get(engine_name)
if re is None:
return
# FIXME(johannes): The usage of the .message attribute has been
# deprecated since Python 2.6. However, the exceptions raised by
# SQLAlchemy can differ when using unicode() and accessing .message.
# An audit across all three supported engines will be necessary to
# ensure there are no regressions.
m = re.match(operational_error.message)
if not m:
return
raise exception.DBDeadlock(operational_error)
def _wrap_db_error(f):
@functools.wraps(f)
def _wrap(self, *args, **kwargs):
try:
assert issubclass(
self.__class__, sqlalchemy.orm.session.Session
), ('_wrap_db_error() can only be applied to methods of '
'subclasses of sqlalchemy.orm.session.Session.')
return f(self, *args, **kwargs)
except UnicodeEncodeError:
raise exception.DBInvalidUnicodeParameter()
except sqla_exc.OperationalError as e:
_raise_if_db_connection_lost(e, self.bind)
_raise_if_deadlock_error(e, self.bind.dialect.name)
# NOTE(comstud): A lot of code is checking for OperationalError
# so let's not wrap it for now.
raise
# note(boris-42): We should catch unique constraint violation and
# wrap it by our own DBDuplicateEntry exception. Unique constraint
# violation is wrapped by IntegrityError.
except sqla_exc.IntegrityError as e:
# note(boris-42): SqlAlchemy doesn't unify errors from different
# DBs so we must do this. Also in some tables (for example
# instance_types) there are more than one unique constraint. This
# means we should get names of columns, which values violate
# unique constraint, from error message.
_raise_if_duplicate_entry_error(e, self.bind.dialect.name)
raise exception.DBError(e)
except Exception as e:
LOG.exception(_LE('DB exception wrapped.'))
raise exception.DBError(e)
return _wrap
def _synchronous_switch_listener(dbapi_conn, connection_rec):
"""Switch sqlite connections to non-synchronous mode."""
dbapi_conn.execute("PRAGMA synchronous = OFF")
def _add_regexp_listener(dbapi_con, con_record):
"""Add REGEXP function to sqlite connections."""
def regexp(expr, item):
reg = re.compile(expr)
return reg.search(six.text_type(item)) is not None
dbapi_con.create_function('regexp', 2, regexp)
def _thread_yield(dbapi_con, con_record):
"""Ensure other greenthreads get a chance to be executed.
If we use eventlet.monkey_patch(), eventlet.greenthread.sleep(0) will
execute instead of time.sleep(0).
Force a context switch. With common database backends (eg MySQLdb and
sqlite), there is no implicit yield caused by network I/O since they are
implemented by C libraries that eventlet cannot monkey patch.
"""
time.sleep(0)
def _ping_listener(engine, dbapi_conn, connection_rec, connection_proxy):
"""Ensures that MySQL, PostgreSQL or DB2 connections are alive.
Borrowed from:
http://groups.google.com/group/sqlalchemy/msg/a4ce563d802c929f
"""
cursor = dbapi_conn.cursor()
try:
ping_sql = 'select 1'
if engine.name == 'ibm_db_sa':
# DB2 requires a table expression
ping_sql = 'select 1 from (values (1)) AS t1'
cursor.execute(ping_sql)
except Exception as ex:
if engine.dialect.is_disconnect(ex, dbapi_conn, cursor):
msg = _LW('Database server has gone away: %s') % ex
LOG.warning(msg)
# if the database server has gone away, all connections in the pool
# have become invalid and we can safely close all of them here,
# rather than waste time on checking of every single connection
engine.dispose()
# this will be handled by SQLAlchemy and will force it to create
# a new connection and retry the original action
raise sqla_exc.DisconnectionError(msg)
else:
raise
def _set_session_sql_mode(dbapi_con, connection_rec, sql_mode=None):
"""Set the sql_mode session variable.
MySQL supports several server modes. The default is None, but sessions
may choose to enable server modes like TRADITIONAL, ANSI,
several STRICT_* modes and others.
Note: passing in '' (empty string) for sql_mode clears
the SQL mode for the session, overriding a potentially set
server default.
"""
cursor = dbapi_con.cursor()
cursor.execute("SET SESSION sql_mode = %s", [sql_mode])
def _mysql_get_effective_sql_mode(engine):
"""Returns the effective SQL mode for connections from the engine pool.
Returns ``None`` if the mode isn't available, otherwise returns the mode.
"""
# Get the real effective SQL mode. Even when unset by
# our own config, the server may still be operating in a specific
# SQL mode as set by the server configuration.
# Also note that the checkout listener will be called on execute to
# set the mode if it's registered.
row = engine.execute("SHOW VARIABLES LIKE 'sql_mode'").fetchone()
if row is None:
return
return row[1]
def _mysql_check_effective_sql_mode(engine):
"""Logs a message based on the effective SQL mode for MySQL connections."""
realmode = _mysql_get_effective_sql_mode(engine)
if realmode is None:
LOG.warning(_LW('Unable to detect effective SQL mode'))
return
LOG.debug('MySQL server mode set to %s', realmode)
# 'TRADITIONAL' mode enables several other modes, so
# we need a substring match here