# copyright 2003-2012 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# This file is part of CubicWeb.
#
# CubicWeb is free software: you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation, either version 2.1 of the License, or (at your option)
# any later version.
#
# CubicWeb is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with CubicWeb. If not, see <http://www.gnu.org/licenses/>.
"""Repository users' and internal' sessions."""
__docformat__ = "restructuredtext en"
import sys
import threading
from time import time
from uuid import uuid4
from warnings import warn
from logilab.common.deprecation import deprecated
from logilab.common.textutils import unormalize
from logilab.common.registry import objectify_predicate
from cubicweb import UnknownEid, QueryError, schema, server
from cubicweb.req import RequestSessionBase
from cubicweb.utils import make_uid
from cubicweb.rqlrewrite import RQLRewriter
from cubicweb.server import ShuttingDown
from cubicweb.server.edition import EditedEntity
NO_UNDO_TYPES = schema.SCHEMA_TYPES.copy()
NO_UNDO_TYPES.add('CWCache')
# is / is_instance_of are usually added by sql hooks except when using
# dataimport.NoHookRQLObjectStore, and we don't want to record them
# anyway in the later case
NO_UNDO_TYPES.add('is')
NO_UNDO_TYPES.add('is_instance_of')
NO_UNDO_TYPES.add('cw_source')
# XXX rememberme,forgotpwd,apycot,vcsfile
@objectify_predicate
def is_user_session(cls, req, **kwargs):
"""return 1 when session is not internal.
This predicate can only be used repository side only. """
return not req.is_internal_session
@objectify_predicate
def is_internal_session(cls, req, **kwargs):
"""return 1 when session is not internal.
This predicate can only be used repository side only. """
return req.is_internal_session
@objectify_predicate
def repairing(cls, req, **kwargs):
"""return 1 when repository is running in repair mode"""
return req.vreg.config.repairing
class transaction(object):
"""Ensure that the transaction is either commited or rolled back at exit
Context manager to enter a transaction for a session: when exiting the
`with` block on exception, call `session.rollback()`, else call
`session.commit()` on normal exit
"""
def __init__(self, session, free_cnxset=True):
self.session = session
self.free_cnxset = free_cnxset
def __enter__(self):
# ensure session has a cnxset
self.session.set_cnxset()
def __exit__(self, exctype, exc, traceback):
if exctype:
self.session.rollback(free_cnxset=self.free_cnxset)
else:
self.session.commit(free_cnxset=self.free_cnxset)
@deprecated('[3.17] use <object>.allow/deny_all_hooks_but instead')
def hooks_control(obj, mode, *categories):
assert mode in (HOOKS_ALLOW_ALL, HOOKS_DENY_ALL)
if mode == HOOKS_ALLOW_ALL:
return obj.allow_all_hooks_but(*categories)
elif mode == HOOKS_DENY_ALL:
return obj.deny_all_hooks_but(*categories)
class _hooks_control(object):
"""context manager to control activated hooks categories.
If mode is session.`HOOKS_DENY_ALL`, given hooks categories will
be enabled.
If mode is session.`HOOKS_ALLOW_ALL`, given hooks categories will
be disabled.
.. sourcecode:: python
with _hooks_control(self.session, self.session.HOOKS_ALLOW_ALL, 'integrity'):
# ... do stuff with all but 'integrity' hooks activated
with _hooks_control(self.session, self.session.HOOKS_DENY_ALL, 'integrity'):
# ... do stuff with none but 'integrity' hooks activated
This is an internal api, you should rather use
:meth:`~cubicweb.server.session.Session.deny_all_hooks_but` or
:meth:`~cubicweb.server.session.Session.allow_all_hooks_but` session
methods.
"""
def __init__(self, session, mode, *categories):
assert mode in (HOOKS_ALLOW_ALL, HOOKS_DENY_ALL)
self.session = session
self.tx = session._tx
self.mode = mode
self.categories = categories
self.oldmode = None
self.changes = ()
def __enter__(self):
self.oldmode = self.tx.hooks_mode
self.tx.hooks_mode = self.mode
if self.mode is HOOKS_DENY_ALL:
self.changes = self.tx.enable_hook_categories(*self.categories)
else:
self.changes = self.tx.disable_hook_categories(*self.categories)
self.tx.ctx_count += 1
def __exit__(self, exctype, exc, traceback):
self.tx.ctx_count -= 1
if self.tx.ctx_count == 0:
self.session._clear_thread_storage(self.tx)
else:
try:
if self.categories:
if self.mode is HOOKS_DENY_ALL:
self.tx.disable_hook_categories(*self.categories)
else:
self.tx.enable_hook_categories(*self.categories)
finally:
self.tx.hooks_mode = self.oldmode
@deprecated('[3.17] use <object>.security_enabled instead')
def security_enabled(obj, *args, **kwargs):
return obj.security_enabled(*args, **kwargs)
class _security_enabled(object):
"""context manager to control security w/ session.execute,
By default security is disabled on queries executed on the repository
side.
"""
def __init__(self, session, read=None, write=None):
self.session = session
self.tx = session._tx
self.read = read
self.write = write
self.oldread = None
self.oldwrite = None
def __enter__(self):
if self.read is None:
self.oldread = None
else:
self.oldread = self.tx.read_security
self.tx.read_security = self.read
if self.write is None:
self.oldwrite = None
else:
self.oldwrite = self.tx.write_security
self.tx.write_security = self.write
self.tx.ctx_count += 1
def __exit__(self, exctype, exc, traceback):
self.tx.ctx_count -= 1
if self.tx.ctx_count == 0:
self.session._clear_thread_storage(self.tx)
else:
if self.oldread is not None:
self.tx.read_security = self.oldread
if self.oldwrite is not None:
self.tx.write_security = self.oldwrite
HOOKS_ALLOW_ALL = object()
HOOKS_DENY_ALL = object()
DEFAULT_SECURITY = object() # evaluated to true by design
class SessionClosedError(RuntimeError):
pass
class CnxSetTracker(object):
"""Keep track of which transaction use which cnxset.
There should be one of these object per session (including internal sessions).
Session objects are responsible of creating their CnxSetTracker object.
Transactions should use the :meth:`record` and :meth:`forget` to inform the
tracker of cnxsets they have acquired.
.. automethod:: cubicweb.server.session.CnxSetTracker.record
.. automethod:: cubicweb.server.session.CnxSetTracker.forget
Sessions use the :meth:`close` and :meth:`wait` methods when closing.
.. automethod:: cubicweb.server.session.CnxSetTracker.close
.. automethod:: cubicweb.server.session.CnxSetTracker.wait
This object itself is threadsafe. It also requires caller to acquired its
lock in some situation.
"""
def __init__(self):
self._active = True
self._condition = threading.Condition()
self._record = {}
def __enter__(self):
return self._condition.__enter__()
def __exit__(self, *args):
return self._condition.__exit__(*args)
def record(self, txid, cnxset):
"""Inform the tracker that a txid has acquired a cnxset
This method is to be used by Transaction objects.
This method fails when:
- The txid already has a recorded cnxset.
- The tracker is not active anymore.
Notes about the caller:
(1) It is responsible for retrieving a cnxset.
(2) It must be prepared to release the cnxset if the
`cnxsettracker.forget` call fails.
(3) It should acquire the tracker lock until the very end of the operation.
(4) However it must only lock the CnxSetTracker object after having
retrieved the cnxset to prevent deadlock.
A typical usage look like::
cnxset = repo._get_cnxset() # (1)
try:
with cnxset_tracker: # (3) and (4)
cnxset_tracker.record(caller.id, cnxset)
# (3') operation ends when caller is in expected state only
caller.cnxset = cnxset
except Exception:
repo._free_cnxset(cnxset) # (2)
raise
"""
# dubious since the caller is supposed to have acquired it anyway.
with self._condition:
if not self._active:
raise SessionClosedError('Closed')
old = self._record.get(txid)
if old is not None:
raise ValueError('transaction "%s" already has a cnx_set (%r)'
% (txid, old))
self._record[txid] = cnxset
def forget(self, txid, cnxset):
"""Inform the tracker that a txid have release a cnxset
This methode is to be used by Transaction object.
This method fails when:
- The cnxset for the txid does not match the recorded one.
Notes about the caller:
(1) It is responsible for releasing the cnxset.
(2) It should acquire the tracker lock during the operation to ensure
the internal tracker state is always accurate regarding its own state.
A typical usage look like::
cnxset = caller.cnxset
try:
with cnxset_tracker:
# (2) you can not have caller.cnxset out of sync with
# cnxset_tracker state while unlocked
caller.cnxset = None
cnxset_tracker.forget(caller.id, cnxset)
finally:
cnxset = repo._free_cnxset(cnxset) # (1)
"""
with self._condition:
old = self._record.get(txid, None)
if old is not cnxset:
raise ValueError('recorded cnxset for "%s" mismatch: %r != %r'
% (txid, old, cnxset))
self._record.pop(txid)
self._condition.notify_all()
def close(self):
"""Marks the tracker as inactive.
This method is to be used by Session objects.
An inactive tracker does not accept new records anymore.
"""
with self._condition:
self._active = False
def wait(self, timeout=10):
"""Wait for all recorded cnxsets to be released
This method is to be used by Session objects.
Returns a tuple of transaction ids that remain open.
"""
with self._condition:
if self._active:
raise RuntimeError('Cannot wait on active tracker.'
' Call tracker.close() first')
while self._record and timeout > 0:
start = time()
self._condition.wait(timeout)
timeout -= time() - start
return tuple(self._record)
class Transaction(object):
"""Repository Transaction
Holds all transaction related data
Database connection resources:
:attr:`running_dbapi_query`, boolean flag telling if the executing query
is coming from a dbapi connection or is a query from within the repository
:attr:`cnxset`, the connections set to use to execute queries on sources.
If the transaction is read only, the connection set may be freed between
actual queries. This allows multiple transactions with a reasonably low
connection set pool size. Control mechanism is detailed below.
.. automethod:: cubicweb.server.session.Transaction.set_cnxset
.. automethod:: cubicweb.server.session.Transaction.free_cnxset
:attr:`mode`, string telling the connections set handling mode, may be one
of 'read' (connections set may be freed), 'write' (some write was done in
the connections set, it can't be freed before end of the transaction),
'transaction' (we want to keep the connections set during all the
transaction, with or without writing)
Internal transaction data:
:attr:`data` is a dictionary containing some shared data
cleared at the end of the transaction. Hooks and operations may put
arbitrary data in there, and this may also be used as a communication
channel between the client and the repository.
:attr:`pending_operations`, ordered list of operations to be processed on
commit/rollback
:attr:`commit_state`, describing the transaction commit state, may be one
of None (not yet committing), 'precommit' (calling precommit event on
operations), 'postcommit' (calling postcommit event on operations),
'uncommitable' (some :exc:`ValidationError` or :exc:`Unauthorized` error
has been raised during the transaction and so it must be rolled back).
Hooks controls:
:attr:`hooks_mode`, may be either `HOOKS_ALLOW_ALL` or `HOOKS_DENY_ALL`.
:attr:`enabled_hook_cats`, when :attr:`hooks_mode` is
`HOOKS_DENY_ALL`, this set contains hooks categories that are enabled.
:attr:`disabled_hook_cats`, when :attr:`hooks_mode` is
`HOOKS_ALLOW_ALL`, this set contains hooks categories that are disabled.
Security level Management:
:attr:`read_security` and :attr:`write_security`, boolean flags telling if
read/write security is currently activated.
"""
def __init__(self, txid, session, rewriter):
#: transaction unique id
self.transactionid = txid
#: reentrance handling
self.ctx_count = 0
#: server.Repository object
self.repo = session.repo
self.vreg = self.repo.vreg
#: connection handling mode
self.mode = session.default_mode
#: connection set used to execute queries on sources
self._cnxset = None
#: CnxSetTracker used to report cnxset usage
self._cnxset_tracker = session._cnxset_tracker
#: is this transaction from a client or internal to the repo
self.running_dbapi_query = True
#: dict containing arbitrary data cleared at the end of the transaction
self.data = {}
#: ordered list of operations to be processed on commit/rollback
self.pending_operations = []
#: (None, 'precommit', 'postcommit', 'uncommitable')
self.commit_state = None
### hook control attribute
self.hooks_mode = HOOKS_ALLOW_ALL
self.disabled_hook_cats = set()
self.enabled_hook_cats = set()
self.pruned_hooks_cache = {}
### security control attributes
self._read_security = DEFAULT_SECURITY # handled by a property
self.write_security = DEFAULT_SECURITY
# undo control
config = session.repo.config
if config.creating or config.repairing or session.is_internal_session:
self.undo_actions = False
else:
self.undo_actions = config['undo-enabled']
# RQLRewriter are not thread safe
self._rewriter = rewriter
@property
def transaction_data(self):
return self.data
def clear(self):
"""reset internal data"""
self.data = {}
#: ordered list of operations to be processed on commit/rollback
self.pending_operations = []
#: (None, 'precommit', 'postcommit', 'uncommitable')
self.commit_state = None
self.pruned_hooks_cache = {}
# Connection Set Management ###############################################
@property
def cnxset(self):
return self._cnxset
@cnxset.setter
def cnxset(self, new_cnxset):
with self._cnxset_tracker:
old_cnxset = self._cnxset
if new_cnxset is old_cnxset:
return #nothing to do
if old_cnxset is not None:
self._cnxset = None
self.ctx_count -= 1
self._cnxset_tracker.forget(self.transactionid, old_cnxset)
if new_cnxset is not None:
self._cnxset_tracker.record(self.transactionid, new_cnxset)
self._cnxset = new_cnxset
self.ctx_count += 1
def set_cnxset(self):
"""the transaction need a connections set to execute some queries"""
if self.cnxset is None:
cnxset = self.repo._get_cnxset()
try:
self.cnxset = cnxset
try:
cnxset.cnxset_set()
except:
self.cnxset = None
raise
except:
self.repo._free_cnxset(cnxset)
raise
return self.cnxset
def free_cnxset(self, ignoremode=False):
"""the transaction is no longer using its connections set, at least for some time"""
# cnxset may be none if no operation has been done since last commit
# or rollback
cnxset = self.cnxset
if cnxset is not None and (ignoremode or self.mode == 'read'):
try:
self.cnxset = None
finally:
cnxset.cnxset_freed()
self.repo._free_cnxset(cnxset)
# Entity cache management #################################################
#
# The transaction entity cache as held in tx.data is removed at the
# end of the transaction (commit and rollback)
#
# XXX transaction level caching may be a pb with multiple repository
# instances, but 1. this is probably not the only one :$ and 2. it may be
# an acceptable risk. Anyway we could activate it or not according to a
# configuration option
def set_entity_cache(self, entity):
"""Add `entity` to the transaction entity cache"""
ecache = self.data.setdefault('ecache', {})
ecache.setdefault(entity.eid, entity)
def entity_cache(self, eid):
"""get cache entity for `eid`"""
return self.data['ecache'][eid]
def cached_entities(self):
"""return the whole entity cache"""
return self.data.get('ecache', {}).values()
def drop_entity_cache(self, eid=None):
"""drop entity from the cache
If eid is None, the whole cache is dropped"""
if eid is None:
self.data.pop('ecache', None)
else:
del self.data['ecache'][eid]
# Tracking of entities added of removed in the transaction ##################
def deleted_in_transaction(self, eid):
"""return True if the entity of the given eid is being deleted in the
current transaction
"""
return eid in self.data.get('pendingeids', ())
def added_in_transaction(self, eid):
"""return True if the entity of the given eid is being created in the
current transaction
"""
return eid in self.data.get('neweids', ())
# Operation management ####################################################
def add_operation(self, operation, index=None):
"""add an operation to be executed at the end of the transaction"""
if index is None:
self.pending_operations.append(operation)
else:
self.pending_operations.insert(index, operation)
# Hooks control ###########################################################
def disable_hook_categories(self, *categories):
"""disable the given hook categories:
- on HOOKS_DENY_ALL mode, ensure those categories are not enabled
- on HOOKS_ALLOW_ALL mode, ensure those categories are disabled
"""
changes = set()
self.pruned_hooks_cache.clear()
categories = set(categories)
if self.hooks_mode is HOOKS_DENY_ALL:
enabledcats = self.enabled_hook_cats
changes = enabledcats & categories
enabledcats -= changes # changes is small hence faster
else:
disabledcats = self.disabled_hook_cats
changes = categories - disabledcats
disabledcats |= changes # changes is small hence faster
return tuple(changes)
def enable_hook_categories(self, *categories):
"""enable the given hook categories:
- on HOOKS_DENY_ALL mode, ensure those categories are enabled
- on HOOKS_ALLOW_ALL mode, ensure those categories are not disabled
"""
changes = set()
self.pruned_hooks_cache.clear()
categories = set(categories)
if self.hooks_mode is HOOKS_DENY_ALL:
enabledcats = self.enabled_hook_cats
changes = categories - enabledcats
enabledcats |= changes # changes is small hence faster
else:
disabledcats = self.disabled_hook_cats
changes = disabledcats & categories
disabledcats -= changes # changes is small hence faster
return tuple(changes)
def is_hook_category_activated(self, category):
"""return a boolean telling if the given category is currently activated
or not
"""
if self.hooks_mode is HOOKS_DENY_ALL:
return category in self.enabled_hook_cats
return category not in self.disabled_hook_cats
def is_hook_activated(self, hook):
"""return a boolean telling if the given hook class is currently
activated or not
"""
return self.is_hook_category_activated(hook.category)
# Security management #####################################################
@property
def read_security(self):
return self._read_security
@read_security.setter
def read_security(self, activated):
oldmode = self._read_security
self._read_security = activated
# running_dbapi_query used to detect hooks triggered by a 'dbapi' query
# (eg not issued on the session). This is tricky since we the execution
# model of a (write) user query is:
#
# repository.execute (security enabled)
# \-> querier.execute
# \-> repo.glob_xxx (add/update/delete entity/relation)
# \-> deactivate security before calling hooks
# \-> WE WANT TO CHECK QUERY NATURE HERE
# \-> potentially, other calls to querier.execute
#
# so we can't rely on simply checking session.read_security, but
# recalling the first transition from DEFAULT_SECURITY to something
# else (False actually) is not perfect but should be enough
#
# also reset running_dbapi_query to true when we go back to
# DEFAULT_SECURITY
self.running_dbapi_query = (oldmode is DEFAULT_SECURITY
or activated is DEFAULT_SECURITY)
# undo support ############################################################
def ertype_supports_undo(self, ertype):
return self.undo_actions and ertype not in NO_UNDO_TYPES
def transaction_uuid(self, set=True):
uuid = self.data.get('tx_uuid')
if set and uuid is None:
raise KeyError
return uuid
def transaction_inc_action_counter(self):
num = self.data.setdefault('tx_action_count', 0) + 1
self.data['tx_action_count'] = num
return num
# db-api like interface ###################################################
def source_defs(self):
return self.repo.source_defs()
def describe(self, eid, asdict=False):
"""return a tuple (type, sourceuri, extid) for the entity with id <eid>"""
metas = self.repo.type_and_source_from_eid(eid, self)
if asdict:
return dict(zip(('type', 'source', 'extid', 'asource'), metas))
# XXX :-1 for cw compat, use asdict=True for full information
return metas[:-1]
def source_from_eid(self, eid):
"""return the source where the entity with id <eid> is located"""
return self.repo.source_from_eid(eid, self)
# resource accessors ######################################################
def system_sql(self, sql, args=None, rollback_on_failure=True):
"""return a sql cursor on the system database"""
if sql.split(None, 1)[0].upper() != 'SELECT':
self.mode = 'write'
source = self.cnxset.source('system')
try:
return source.doexec(self, sql, args, rollback=rollback_on_failure)
except (source.OperationalError, source.InterfaceError):
if not rollback_on_failure:
raise
source.warning("trying to reconnect")
self.cnxset.reconnect(source)
return source.doexec(self, sql, args, rollback=rollback_on_failure)
def rtype_eids_rdef(self, rtype, eidfrom, eidto):
# use type_and_source_from_eid instead of type_from_eid for optimization
# (avoid two extra methods call)
subjtype = self.repo.type_and_source_from_eid(eidfrom, self)[0]
objtype = self.repo.type_and_source_from_eid(eidto, self)[0]
return self.vreg.schema.rschema(rtype).rdefs[(subjtype, objtype)]
def tx_attr(attr_name, writable=False):
"""return a property to forward attribute access to transaction.
This is to be used by session"""
args = {}
def attr_from_tx(session):
return getattr(session._tx, attr_name)
args['fget'] = attr_from_tx
if writable:
def write_attr(session, value):
return setattr(session._tx, attr_name, value)
args['fset'] = write_attr
return property(**args)
def tx_meth(meth_name):
"""return a function forwarding calls to transaction.
This is to be used by session"""
def meth_from_tx(session, *args, **kwargs):
return getattr(session._tx, meth_name)(*args, **kwargs)
return meth_from_tx
class Session(RequestSessionBase):
"""Repository user session
This ties all together:
* session id,
* user,
* connections set,
* other session data.
**About session storage / transactions**
Here is a description of internal session attributes. Besides :attr:`data`
and :attr:`transaction_data`, you should not have to use attributes
described here but higher level APIs.
:attr:`data` is a dictionary containing shared data, used to communicate
extra information between the client and the repository
:attr:`_txs` is a dictionary of :class:`TransactionData` instance, one
for each running transaction. The key is the transaction id. By default
the transaction id is the thread name but it can be otherwise (per dbapi
cursor for instance, or per thread name *from another process*).
:attr:`__threaddata` is a thread local storage whose `tx` attribute
refers to the proper instance of :class:`Transaction` according to the
transaction.
You should not have to use neither :attr:`_tx` nor :attr:`__threaddata`,
simply access transaction data transparently through the :attr:`_tx`
property. Also, you usually don't have to access it directly since current
transaction's data may be accessed/modified through properties / methods:
:attr:`transaction_data`, similarly to :attr:`data`, is a dictionary
containing some shared data that should be cleared at the end of the
transaction. Hooks and operations may put arbitrary data in there, and
this may also be used as a communication channel between the client and
the repository.
.. automethod:: cubicweb.server.session.Session.get_shared_data
.. automethod:: cubicweb.server.session.Session.set_shared_data
.. automethod:: cubicweb.server.session.Session.added_in_transaction
.. automethod:: cubicweb.server.session.Session.deleted_in_transaction
Transaction state information:
:attr:`running_dbapi_query`, boolean flag telling if the executing query
is coming from a dbapi connection or is a query from within the repository
:attr:`cnxset`, the connections set to use to execute queries on sources.
During a transaction, the connection set may be freed so that is may be
used by another session as long as no writing is done. This means we can
have multiple sessions with a reasonably low connections set pool size.
.. automethod:: cubicweb.server.session.set_cnxset
.. automethod:: cubicweb.server.session.free_cnxset
:attr:`mode`, string telling the connections set handling mode, may be one
of 'read' (connections set may be freed), 'write' (some write was done in
the connections set, it can't be freed before end of the transaction),
'transaction' (we want to keep the connections set during all the
transaction, with or without writing)
:attr:`pending_operations`, ordered list of operations to be processed on
commit/rollback
:attr:`commit_state`, describing the transaction commit state, may be one
of None (not yet committing), 'precommit' (calling precommit event on
operations), 'postcommit' (calling postcommit event on operations),
'uncommitable' (some :exc:`ValidationError` or :exc:`Unauthorized` error
has been raised during the transaction and so it must be rolled back).
.. automethod:: cubicweb.server.session.Session.commit
.. automethod:: cubicweb.server.session.Session.rollback
.. automethod:: cubicweb.server.session.Session.close
.. automethod:: cubicweb.server.session.Session.closed
Security level Management:
:attr:`read_security` and :attr:`write_security`, boolean flags telling if
read/write security is currently activated.
.. automethod:: cubicweb.server.session.Session.security_enabled
Hooks Management:
:attr:`hooks_mode`, may be either `HOOKS_ALLOW_ALL` or `HOOKS_DENY_ALL`.
:attr:`enabled_hook_categories`, when :attr:`hooks_mode` is
`HOOKS_DENY_ALL`, this set contains hooks categories that are enabled.
:attr:`disabled_hook_categories`, when :attr:`hooks_mode` is
`HOOKS_ALLOW_ALL`, this set contains hooks categories that are disabled.
.. automethod:: cubicweb.server.session.Session.deny_all_hooks_but
.. automethod:: cubicweb.server.session.Session.allow_all_hooks_but
.. automethod:: cubicweb.server.session.Session.is_hook_category_activated
.. automethod:: cubicweb.server.session.Session.is_hook_activated
Data manipulation:
.. automethod:: cubicweb.server.session.Session.add_relation
.. automethod:: cubicweb.server.session.Session.add_relations
.. automethod:: cubicweb.server.session.Session.delete_relation
Other:
.. automethod:: cubicweb.server.session.Session.call_service
"""
is_request = False
is_internal_session = False
def __init__(self, user, repo, cnxprops=None, _id=None):
super(Session, self).__init__(repo.vreg)
self.id = _id or make_uid(unormalize(user.login).encode('UTF8'))
self.user = user
self.repo = repo
self.timestamp = time()
self.default_mode = 'read'
# short cut to querier .execute method
self._execute = repo.querier.execute
# shared data, used to communicate extra information between the client
# and the rql server
self.data = {}
# i18n initialization
self.set_language(user.prefered_language())
### internals
# Transaction of this section
self._txs = {}
# Data local to the thread
self.__threaddata = threading.local()
self._cnxset_tracker = CnxSetTracker()
self._closed = False
self._lock = threading.RLock()
def __unicode__(self):
return '<session %s (%s 0x%x)>' % (
unicode(self.user.login), self.id, id(self))
def get_tx(self, txid):
"""return the <txid> transaction attached to this session
Transaction is created if necessary"""
with self._lock: # no transaction exist with the same id
try:
if self.closed:
raise SessionClosedError('try to access connections set on a closed session %s' % self.id)
tx = self._txs[txid]
except KeyError:
rewriter = RQLRewriter(self)
tx = Transaction(txid, self, rewriter)
self._txs[txid] = tx
return tx
def set_tx(self, txid=None):
"""set the default transaction of the current thread to <txid>
Transaction is created if necessary"""
if txid is None:
txid = threading.currentThread().getName()
self.__threaddata.tx = self.get_tx(txid)
@property
def _tx(self):
"""default transaction for current session in current thread"""
try:
return self.__threaddata.tx
except AttributeError:
self.set_tx()
return self.__threaddata.tx
def get_option_value(self, option, foreid=None):
return self.repo.get_option_value(option, foreid)
def transaction(self, free_cnxset=True):
"""return context manager to enter a transaction for the session: when
exiting the `with` block on exception, call `session.rollback()`, else
call `session.commit()` on normal exit.
The `free_cnxset` will be given to rollback/commit methods to indicate
whether the connections set should be freed or not.
"""
return transaction(self, free_cnxset)
@deprecated('[3.17] do not use hijack_user. create new Session object')
def hijack_user(self, user):
"""return a fake request/session using specified user"""
session = Session(user, self.repo)
tx = session._tx
tx.cnxset = self.cnxset
# share pending_operations, else operation added in the hi-jacked
# session such as SendMailOp won't ever be processed
tx.pending_operations = self.pending_operations
# everything in tx.data should be copied back but the entity
# type cache we don't want to avoid security pb
tx.data = self._tx.data.copy()
tx.data.pop('ecache', None)
return session
def add_relation(self, fromeid, rtype, toeid):
"""provide direct access to the repository method to add a relation.
This is equivalent to the following rql query:
SET X rtype Y WHERE X eid fromeid, T eid toeid
without read security check but also all the burden of rql execution.
You may use this in hooks when you know both eids of the relation you
want to add.
"""
self.add_relations([(rtype, [(fromeid, toeid)])])
def add_relations(self, relations):
'''set many relation using a shortcut similar to the one in add_relation
relations is a list of 2-uples, the first element of each
2-uple is the rtype, and the second is a list of (fromeid,
toeid) tuples
'''
edited_entities = {}
relations_dict = {}
with self.security_enabled(False, False):
for rtype, eids in relations:
if self.vreg.schema[rtype].inlined:
for fromeid, toeid in eids:
if fromeid not in edited_entities:
entity = self.entity_from_eid(fromeid)
edited = EditedEntity(entity)
edited_entities[fromeid] = edited
else:
edited = edited_entities[fromeid]
edited.edited_attribute(rtype, toeid)
else:
relations_dict[rtype] = eids
self.repo.glob_add_relations(self, relations_dict)
for edited in edited_entities.itervalues():
self.repo.glob_update_entity(self, edited)
def delete_relation(self, fromeid, rtype, toeid):
"""provide direct access to the repository method to delete a relation.
This is equivalent to the following rql query:
DELETE X rtype Y WHERE X eid fromeid, T eid toeid
without read security check but also all the burden of rql execution.
You may use this in hooks when you know both eids of the relation you
want to delete.
"""
with self.security_enabled(False, False):
if self.vreg.schema[rtype].inlined:
entity = self.entity_from_eid(fromeid)
entity.cw_attr_cache[rtype] = None
self.repo.glob_update_entity(self, entity, set((rtype,)))
else:
self.repo.glob_delete_relation(self, fromeid, rtype, toeid)
# relations cache handling #################################################
def update_rel_cache_add(self, subject, rtype, object, symmetric=False):
self._update_entity_rel_cache_add(subject, rtype, 'subject', object)
if symmetric:
self._update_entity_rel_cache_add(object, rtype, 'subject', subject)
else:
self._update_entity_rel_cache_add(object, rtype, 'object', subject)
def update_rel_cache_del(self, subject, rtype, object, symmetric=False):
self._update_entity_rel_cache_del(subject, rtype, 'subject', object)
if symmetric:
self._update_entity_rel_cache_del(object, rtype, 'object', object)
else:
self._update_entity_rel_cache_del(object, rtype, 'object', subject)
def _update_entity_rel_cache_add(self, eid, rtype, role, targeteid):
try:
entity = self.entity_cache(eid)
except KeyError:
return
rcache = entity.cw_relation_cached(rtype, role)
if rcache is not None:
rset, entities = rcache
rset = rset.copy()
entities = list(entities)
rset.rows.append([targeteid])
if not isinstance(rset.description, list): # else description not set
rset.description = list(rset.description)
rset.description.append([self.describe(targeteid)[0]])
targetentity = self.entity_from_eid(targeteid)
if targetentity.cw_rset is None:
targetentity.cw_rset = rset
targetentity.cw_row = rset.rowcount
targetentity.cw_col = 0
rset.rowcount += 1
entities.append(targetentity)
entity._cw_related_cache['%s_%s' % (rtype, role)] = (
rset, tuple(entities))
def _update_entity_rel_cache_del(self, eid, rtype, role, targeteid):
try:
entity = self.entity_cache(eid)
except KeyError:
return
rcache = entity.cw_relation_cached(rtype, role)
if rcache is not None:
rset, entities = rcache
for idx, row in enumerate(rset.rows):
if row[0] == targeteid:
break
else:
# this may occurs if the cache has been filed by a hook
# after the database update
self.debug('cache inconsistency for %s %s %s %s', eid, rtype,
role, targeteid)
return
rset = rset.copy()
entities = list(entities)
del rset.rows[idx]
if isinstance(rset.description, list): # else description not set
del rset.description[idx]
del entities[idx]
rset.rowcount -= 1
entity._cw_related_cache['%s_%s' % (rtype, role)] = (
rset, tuple(entities))
# resource accessors ######################################################
system_sql = tx_meth('system_sql')
deleted_in_transaction = tx_meth('deleted_in_transaction')
added_in_transaction = tx_meth('added_in_transaction')
rtype_eids_rdef = tx_meth('rtype_eids_rdef')
# security control #########################################################
def security_enabled(self, read=None, write=None):
return _security_enabled(self, read=read, write=write)
read_security = tx_attr('read_security', writable=True)
write_security = tx_attr('write_security', writable=True)
running_dbapi_query = tx_attr('running_dbapi_query')
# hooks activation control #################################################
# all hooks should be activated during normal execution
def allow_all_hooks_but(self, *categories):
return _hooks_control(self, HOOKS_ALLOW_ALL, *categories)
def deny_all_hooks_but(self, *categories):
return _hooks_control(self, HOOKS_DENY_ALL, *categories)
hooks_mode = tx_attr('hooks_mode')
disabled_hook_categories = tx_attr('disabled_hook_cats')
enabled_hook_categories = tx_attr('enabled_hook_cats')
disable_hook_categories = tx_meth('disable_hook_categories')
enable_hook_categories = tx_meth('enable_hook_categories')
is_hook_category_activated = tx_meth('is_hook_category_activated')
is_hook_activated = tx_meth('is_hook_activated')
# connection management ###################################################
def keep_cnxset_mode(self, mode):
"""set `mode`, e.g. how the session will keep its connections set:
* if mode == 'write', the connections set is freed after each ready
query, but kept until the transaction's end (eg commit or rollback)
when a write query is detected (eg INSERT/SET/DELETE queries)
* if mode == 'transaction', the connections set is only freed after the
transaction's end
notice that a repository has a limited set of connections sets, and a
session has to wait for a free connections set to run any rql query
(unless it already has one set).
"""
assert mode in ('transaction', 'write')
if mode == 'transaction':
self.default_mode = 'transaction'
else: # mode == 'write'
self.default_mode = 'read'
mode = tx_attr('mode', writable=True)
commit_state = tx_attr('commit_state', writable=True)
@property
def cnxset(self):
"""connections set, set according to transaction mode for each query"""
if self._closed:
self.free_cnxset(True)
raise SessionClosedError('try to access connections set on a closed session %s' % self.id)
return self._tx.cnxset
def set_cnxset(self):
"""the session need a connections set to execute some queries"""
with self._lock: # can probably be removed
if self._closed:
self.free_cnxset(True)
raise SessionClosedError('try to set connections set on a closed session %s' % self.id)
return self._tx.set_cnxset()
free_cnxset = tx_meth('free_cnxset')
def _touch(self):
"""update latest session usage timestamp and reset mode to read"""
self.timestamp = time()
self.local_perm_cache.clear() # XXX simply move in tx.data, no?
# shared data handling ###################################################
def get_shared_data(self, key, default=None, pop=False, txdata=False):
"""return value associated to `key` in session data"""
if txdata:
data = self._tx.data
else:
data = self.data
if pop:
return data.pop(key, default)
else:
return data.get(key, default)
def set_shared_data(self, key, value, txdata=False):
"""set value associated to `key` in session data"""
if txdata:
self._tx.data[key] = value
else:
self.data[key] = value
# server-side service call #################################################
def call_service(self, regid, async=False, **kwargs):
return self.repo._call_service_with_session(self, regid, async,
**kwargs)
# request interface #######################################################
@property
def cursor(self):
"""return a rql cursor"""
return self
set_entity_cache = tx_meth('set_entity_cache')
entity_cache = tx_meth('entity_cache')
cache_entities = tx_meth('cached_entities')
drop_entity_cache = tx_meth('drop_entity_cache')
def from_controller(self):
"""return the id (string) of the controller issuing the request (no
sense here, always return 'view')
"""
return 'view'
source_defs = tx_meth('source_defs')
describe = tx_meth('describe')
source_from_eid = tx_meth('source_from_eid')
def execute(self, rql, kwargs=None, eid_key=None, build_descr=True):
"""db-api like method directly linked to the querier execute method.
See :meth:`cubicweb.dbapi.Cursor.execute` documentation.
"""
if eid_key is not None:
warn('[3.8] eid_key is deprecated, you can safely remove this argument',
DeprecationWarning, stacklevel=2)
self.timestamp = time() # update timestamp
rset = self._execute(self, rql, kwargs, build_descr)
rset.req = self
return rset
def _clear_thread_data(self, free_cnxset=True):
"""remove everything from the thread local storage, except connections set
which is explicitly removed by free_cnxset, and mode which is set anyway
by _touch
"""
try:
tx = self.__threaddata.tx
except AttributeError:
pass
else:
if free_cnxset:
self.free_cnxset()
if tx.ctx_count == 0:
self._clear_thread_storage(tx)
else:
self._clear_tx_storage(tx)
else:
self._clear_tx_storage(tx)
def _clear_thread_storage(self, tx):
self._txs.pop(tx.transactionid, None)
try:
del self.__threaddata.tx
except AttributeError:
pass
def _clear_tx_storage(self, tx):
tx.clear()
tx._rewriter = RQLRewriter(self)
def commit(self, free_cnxset=True, reset_pool=None):
"""commit the current session's transaction"""
if reset_pool is not None:
warn('[3.13] use free_cnxset argument instead for reset_pool',
DeprecationWarning, stacklevel=2)
free_cnxset = reset_pool
if self.cnxset is None:
assert not self.pending_operations
self._clear_thread_data()
self._touch()
self.debug('commit session %s done (no db activity)', self.id)
return
cstate = self.commit_state
if cstate == 'uncommitable':
raise QueryError('transaction must be rolled back')
if cstate is not None:
return
# on rollback, an operation should have the following state
# information:
# - processed by the precommit/commit event or not
# - if processed, is it the failed operation
debug = server.DEBUG & server.DBG_OPS
try:
# by default, operations are executed with security turned off
with self.security_enabled(False, False):
processed = []
self.commit_state = 'precommit'
if debug:
print self.commit_state, '*' * 20
try:
while self.pending_operations:
operation = self.pending_operations.pop(0)
operation.processed = 'precommit'
processed.append(operation)
if debug:
print operation
operation.handle_event('precommit_event')
self.pending_operations[:] = processed
self.debug('precommit session %s done', self.id)
except BaseException:
# save exception context, it may be clutered below by
# exception in revert_* event
exc_info = sys.exc_info()
# if error on [pre]commit:
#
# * set .failed = True on the operation causing the failure
# * call revert<event>_event on processed operations
# * call rollback_event on *all* operations
#
# that seems more natural than not calling rollback_event
# for processed operations, and allow generic rollback
# instead of having to implements rollback, revertprecommit
# and revertcommit, that will be enough in mont case.
operation.failed = True
if debug:
print self.commit_state, '*' * 20
for operation in reversed(processed):
if debug:
print operation
try:
operation.handle_event('revertprecommit_event')
except BaseException:
self.critical('error while reverting precommit',
exc_info=True)
# XXX use slice notation since self.pending_operations is a
# read-only property.
self.pending_operations[:] = processed + self.pending_operations
self.rollback(free_cnxset)
raise exc_info[0], exc_info[1], exc_info[2]
self.cnxset.commit()
self.commit_state = 'postcommit'
if debug:
print self.commit_state, '*' * 20
while self.pending_operations:
operation = self.pending_operations.pop(0)
if debug:
print operation
operation.processed = 'postcommit'
try:
operation.handle_event('postcommit_event')
except BaseException:
self.critical('error while postcommit',
exc_info=sys.exc_info())
self.debug('postcommit session %s done', self.id)
return self.transaction_uuid(set=False)
finally:
self._touch()
if free_cnxset:
self.free_cnxset(ignoremode=True)
self._clear_thread_data(free_cnxset)
def rollback(self, free_cnxset=True, reset_pool=None):
"""rollback the current session's transaction"""
if reset_pool is not None:
warn('[3.13] use free_cnxset argument instead for reset_pool',
DeprecationWarning, stacklevel=2)
free_cnxset = reset_pool
# don't use self.cnxset, rollback may be called with _closed == True
cnxset = self._tx.cnxset
if cnxset is None:
self._clear_thread_data()
self._touch()
self.debug('rollback session %s done (no db activity)', self.id)
return
try:
# by default, operations are executed with security turned off
with self.security_enabled(False, False):
while self.pending_operations:
try:
operation = self.pending_operations.pop(0)
operation.handle_event('rollback_event')
except BaseException:
self.critical('rollback error', exc_info=sys.exc_info())
continue
cnxset.rollback()
self.debug('rollback for session %s done', self.id)
finally:
self._touch()
if free_cnxset:
self.free_cnxset(ignoremode=True)
self._clear_thread_data(free_cnxset)
def close(self):
# do not close connections set on session close, since they are shared now
tracker = self._cnxset_tracker
with self._lock:
self._closed = True
tracker.close()
self.rollback()
self.debug('waiting for open transaction of session: %s', self)
timeout = 10
pendings = tracker.wait(timeout)
if pendings:
self.error('%i transaction still alive after 10 seconds, will close '
'session anyway', len(pendings))
for txid in pendings:
tx = self._txs.get(txid)
if tx is not None:
# drop tx.cnxset
with tracker:
try:
cnxset = tx.cnxset
if cnxset is None:
continue
tx.cnxset = None
except RuntimeError:
msg = 'issue while force free of cnxset in %s'
self.error(msg, tx)
# cnxset.reconnect() do an hard reset of the cnxset
# it force it to be freed
cnxset.reconnect()
self.repo._free_cnxset(cnxset)
del self.__threaddata
del self._txs
@property
def closed(self):
return not hasattr(self, '_txs')
# transaction data/operations management ##################################
transaction_data = tx_attr('data')
pending_operations = tx_attr('pending_operations')
pruned_hooks_cache = tx_attr('pruned_hooks_cache')
add_operation = tx_meth('add_operation')
# undo support ############################################################
ertype_supports_undo = tx_meth('ertype_supports_undo')
transaction_inc_action_counter = tx_meth('transaction_inc_action_counter')
def transaction_uuid(self, set=True):
try:
return self._tx.transaction_uuid(set=set)
except KeyError:
self._tx.data['tx_uuid'] = uuid = uuid4().hex
self.repo.system_source.start_undoable_transaction(self, uuid)
return uuid
# querier helpers #########################################################
rql_rewriter = tx_attr('_rewriter')
# deprecated ###############################################################
@deprecated('[3.13] use getattr(session.rtype_eids_rdef(rtype, eidfrom, eidto), prop)')
def schema_rproperty(self, rtype, eidfrom, eidto, rprop):
return getattr(self.rtype_eids_rdef(rtype, eidfrom, eidto), rprop)
@property
@deprecated("[3.13] use .cnxset attribute instead of .pool")
def pool(self):
return self.cnxset
@deprecated("[3.13] use .set_cnxset() method instead of .set_pool()")
def set_pool(self):
return self.set_cnxset()
@deprecated("[3.13] use .free_cnxset() method instead of .reset_pool()")
def reset_pool(self):
return self.free_cnxset()
# these are overridden by set_log_methods below
# only defining here to prevent pylint from complaining
info = warning = error = critical = exception = debug = lambda msg,*a,**kw: None
Session.HOOKS_ALLOW_ALL = HOOKS_ALLOW_ALL
Session.HOOKS_DENY_ALL = HOOKS_DENY_ALL
Session.DEFAULT_SECURITY = DEFAULT_SECURITY
class InternalSession(Session):
"""special session created internaly by the repository"""
is_internal_session = True
running_dbapi_query = False
def __init__(self, repo, cnxprops=None, safe=False):
super(InternalSession, self).__init__(InternalManager(), repo, cnxprops,
_id='internal')
self.user._cw = self # XXX remove when "vreg = user._cw.vreg" hack in entity.py is gone
if not safe:
self.disable_hook_categories('integrity')
self._tx.ctx_count += 1
def __enter__(self):
return self
def __exit__(self, exctype, excvalue, tb):
self.close()
@property
def cnxset(self):
"""connections set, set according to transaction mode for each query"""
if self.repo.shutting_down:
self.free_cnxset(True)
raise ShuttingDown('repository is shutting down')
return self._tx.cnxset
class InternalManager(object):
"""a manager user with all access rights used internally for task such as
bootstrapping the repository or creating regular users according to
repository content
"""
def __init__(self):
self.eid = -1
self.login = u'__internal_manager__'
self.properties = {}
def matching_groups(self, groups):
return 1
def is_in_group(self, group):
return True
def owns(self, eid):
return True
def property_value(self, key):
if key == 'ui.language':
return 'en'
return None
def prefered_language(self, language=None):
# mock CWUser.prefered_language, mainly for testing purpose
return self.property_value('ui.language')
# CWUser compat for notification ###########################################
def name(self):
return 'cubicweb'
class _IEmailable:
@staticmethod
def get_email():
return ''
def cw_adapt_to(self, iface):
if iface == 'IEmailable':
return self._IEmailable
return None
from logging import getLogger
from cubicweb import set_log_methods
set_log_methods(Session, getLogger('cubicweb.session'))