Updated SqlAlchemy

This commit is contained in:
2017-04-15 16:27:12 +00:00
parent 2c790e1fe1
commit e3267d4bda
59 changed files with 30236 additions and 26049 deletions

View File

@@ -1,96 +1,120 @@
# scoping.py
# Copyright (C) the SQLAlchemy authors and contributors
# orm/scoping.py
# Copyright (C) 2005-2017 the SQLAlchemy authors and contributors
# <see AUTHORS file>
#
# This module is part of SQLAlchemy and is released under
# the MIT License: http://www.opensource.org/licenses/mit-license.php
import sqlalchemy.exceptions as sa_exc
from sqlalchemy.util import ScopedRegistry, ThreadLocalRegistry, \
to_list, get_cls_kwargs, deprecated
from sqlalchemy.orm import (
EXT_CONTINUE, MapperExtension, class_mapper, object_session
)
from sqlalchemy.orm import exc as orm_exc
from sqlalchemy.orm.session import Session
from .. import exc as sa_exc
from ..util import ScopedRegistry, ThreadLocalRegistry, warn
from . import class_mapper, exc as orm_exc
from .session import Session
__all__ = ['ScopedSession']
__all__ = ['scoped_session']
class ScopedSession(object):
"""Provides thread-local management of Sessions.
class scoped_session(object):
"""Provides scoped management of :class:`.Session` objects.
Usage::
Session = scoped_session(sessionmaker(autoflush=True))
... use session normally.
See :ref:`unitofwork_contextual` for a tutorial.
"""
session_factory = None
"""The `session_factory` provided to `__init__` is stored in this
attribute and may be accessed at a later time. This can be useful when
a new non-scoped :class:`.Session` or :class:`.Connection` to the
database is needed."""
def __init__(self, session_factory, scopefunc=None):
"""Construct a new :class:`.scoped_session`.
:param session_factory: a factory to create new :class:`.Session`
instances. This is usually, but not necessarily, an instance
of :class:`.sessionmaker`.
:param scopefunc: optional function which defines
the current scope. If not passed, the :class:`.scoped_session`
object assumes "thread-local" scope, and will use
a Python ``threading.local()`` in order to maintain the current
:class:`.Session`. If passed, the function should return
a hashable token; this token will be used as the key in a
dictionary in order to store and retrieve the current
:class:`.Session`.
"""
self.session_factory = session_factory
if scopefunc:
self.registry = ScopedRegistry(session_factory, scopefunc)
else:
self.registry = ThreadLocalRegistry(session_factory)
self.extension = _ScopedExt(self)
def __call__(self, **kwargs):
if kwargs:
scope = kwargs.pop('scope', False)
def __call__(self, **kw):
r"""Return the current :class:`.Session`, creating it
using the :attr:`.scoped_session.session_factory` if not present.
:param \**kw: Keyword arguments will be passed to the
:attr:`.scoped_session.session_factory` callable, if an existing
:class:`.Session` is not present. If the :class:`.Session` is present
and keyword arguments have been passed,
:exc:`~sqlalchemy.exc.InvalidRequestError` is raised.
"""
if kw:
scope = kw.pop('scope', False)
if scope is not None:
if self.registry.has():
raise sa_exc.InvalidRequestError("Scoped session is already present; no new arguments may be specified.")
raise sa_exc.InvalidRequestError(
"Scoped session is already present; "
"no new arguments may be specified.")
else:
sess = self.session_factory(**kwargs)
sess = self.session_factory(**kw)
self.registry.set(sess)
return sess
else:
return self.session_factory(**kwargs)
return self.session_factory(**kw)
else:
return self.registry()
def remove(self):
"""Dispose of the current contextual session."""
"""Dispose of the current :class:`.Session`, if present.
This will first call :meth:`.Session.close` method
on the current :class:`.Session`, which releases any existing
transactional/connection resources still being held; transactions
specifically are rolled back. The :class:`.Session` is then
discarded. Upon next usage within the same scope,
the :class:`.scoped_session` will produce a new
:class:`.Session` object.
"""
if self.registry.has():
self.registry().close()
self.registry.clear()
@deprecated("Session.mapper is deprecated. "
"Please see http://www.sqlalchemy.org/trac/wiki/UsageRecipes/SessionAwareMapper "
"for information on how to replicate its behavior.")
def mapper(self, *args, **kwargs):
"""return a mapper() function which associates this ScopedSession with the Mapper.
def configure(self, **kwargs):
"""reconfigure the :class:`.sessionmaker` used by this
:class:`.scoped_session`.
DEPRECATED.
See :meth:`.sessionmaker.configure`.
"""
from sqlalchemy.orm import mapper
extension_args = dict((arg, kwargs.pop(arg))
for arg in get_cls_kwargs(_ScopedExt)
if arg in kwargs)
kwargs['extension'] = extension = to_list(kwargs.get('extension', []))
if extension_args:
extension.append(self.extension.configure(**extension_args))
else:
extension.append(self.extension)
return mapper(*args, **kwargs)
def configure(self, **kwargs):
"""reconfigure the sessionmaker used by this ScopedSession."""
if self.registry.has():
warn('At least one scoped session is already present. '
' configure() can not affect sessions that have '
'already been created.')
self.session_factory.configure(**kwargs)
def query_property(self, query_cls=None):
"""return a class property which produces a `Query` object against the
class when called.
"""return a class property which produces a :class:`.Query` object
against the class and the current :class:`.Session` when called.
e.g.::
Session = scoped_session(sessionmaker())
class MyClass(object):
@@ -124,82 +148,37 @@ class ScopedSession(object):
return None
return query()
ScopedSession = scoped_session
"""Old name for backwards compatibility."""
def instrument(name):
def do(self, *args, **kwargs):
return getattr(self.registry(), name)(*args, **kwargs)
return do
for meth in Session.public_methods:
setattr(ScopedSession, meth, instrument(meth))
setattr(scoped_session, meth, instrument(meth))
def makeprop(name):
def set(self, attr):
setattr(self.registry(), name, attr)
def get(self):
return getattr(self.registry(), name)
return property(get, set)
for prop in ('bind', 'dirty', 'deleted', 'new', 'identity_map', 'is_active', 'autoflush'):
setattr(ScopedSession, prop, makeprop(prop))
for prop in ('bind', 'dirty', 'deleted', 'new', 'identity_map',
'is_active', 'autoflush', 'no_autoflush', 'info'):
setattr(scoped_session, prop, makeprop(prop))
def clslevel(name):
def do(cls, *args, **kwargs):
return getattr(Session, name)(*args, **kwargs)
return classmethod(do)
for prop in ('close_all', 'object_session', 'identity_key'):
setattr(ScopedSession, prop, clslevel(prop))
class _ScopedExt(MapperExtension):
def __init__(self, context, validate=False, save_on_init=True):
self.context = context
self.validate = validate
self.save_on_init = save_on_init
self.set_kwargs_on_init = True
def validating(self):
return _ScopedExt(self.context, validate=True)
def configure(self, **kwargs):
return _ScopedExt(self.context, **kwargs)
def instrument_class(self, mapper, class_):
class query(object):
def __getattr__(s, key):
return getattr(self.context.registry().query(class_), key)
def __call__(s):
return self.context.registry().query(class_)
def __get__(self, instance, cls):
return self
if not 'query' in class_.__dict__:
class_.query = query()
if self.set_kwargs_on_init and class_.__init__ is object.__init__:
class_.__init__ = self._default__init__(mapper)
def _default__init__(ext, mapper):
def __init__(self, **kwargs):
for key, value in kwargs.iteritems():
if ext.validate:
if not mapper.get_property(key, resolve_synonyms=False,
raiseerr=False):
raise sa_exc.ArgumentError(
"Invalid __init__ argument: '%s'" % key)
setattr(self, key, value)
return __init__
def init_instance(self, mapper, class_, oldinit, instance, args, kwargs):
if self.save_on_init:
session = kwargs.pop('_sa_session', None)
if session is None:
session = self.context.registry()
session._save_without_cascade(instance)
return EXT_CONTINUE
def init_failed(self, mapper, class_, oldinit, instance, args, kwargs):
sess = object_session(instance)
if sess:
sess.expunge(instance)
return EXT_CONTINUE
def dispose_class(self, mapper, class_):
if hasattr(class_, 'query'):
delattr(class_, 'query')
setattr(scoped_session, prop, clslevel(prop))