# copyright 2003-2011 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."""
from __future__ import with_statement
__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 rql import CoercionError
from rql.nodes import ETYPE_PYOBJ_MAP, etype_from_pyobj
from yams import BASE_TYPES
from cubicweb import Binary, UnknownEid, QueryError, schema
from cubicweb.selectors import objectify_selector
from cubicweb.req import RequestSessionBase
from cubicweb.dbapi import ConnectionProperties
from cubicweb.utils import make_uid, RepeatList
from cubicweb.rqlrewrite import RQLRewriter
from cubicweb.server import ShuttingDown
from cubicweb.server.edition import EditedEntity
ETYPE_PYOBJ_MAP[Binary] = 'Bytes'
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
def _make_description(selected, args, solution):
"""return a description for a result set"""
description = []
for term in selected:
description.append(term.get_type(solution, args))
return description
@objectify_selector
def is_user_session(cls, req, **kwargs):
"""repository side only selector returning 1 if the session is a regular
user session and not an internal session
"""
return not req.is_internal_session
@objectify_selector
def is_internal_session(cls, req, **kwargs):
"""repository side only selector returning 1 if the session is not a regular
user session but an internal session
"""
return req.is_internal_session
@objectify_selector
def repairing(cls, req, **kwargs):
"""repository side only selector returning 1 if the session is not a regular
user session but an internal session
"""
return req.vreg.config.repairing
class transaction(object):
"""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):
pass
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)
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
"""
def __init__(self, session, mode, *categories):
self.session = session
self.mode = mode
self.categories = categories
def __enter__(self):
self.oldmode, self.changes = self.session.init_hooks_mode_categories(
self.mode, self.categories)
def __exit__(self, exctype, exc, traceback):
self.session.reset_hooks_mode_categories(self.oldmode, self.mode, self.changes)
class security_enabled(object):
"""context manager to control security w/ session.execute, since by
default security is disabled on queries executed on the repository
side.
"""
def __init__(self, session, read=None, write=None):
self.session = session
self.read = read
self.write = write
def __enter__(self):
self.oldread, self.oldwrite = self.session.init_security(
self.read, self.write)
def __exit__(self, exctype, exc, traceback):
self.session.reset_security(self.oldread, self.oldwrite)
class TransactionData(object):
def __init__(self, txid):
self.transactionid = txid
self.ctx_count = 0
class Session(RequestSessionBase):
"""Repository usersession, tie a session id, user, connections set and
other session data all together.
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:`_tx_data` 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 `txdata` attribute
refers to the proper instance of :class:`TransactionData` according to the
transaction.
:attr:`_threads_in_transaction` is a set of (thread, connections set)
referencing threads that currently hold a connections set for the session.
You should not have to use neither :attr:`_txdata` nor :attr:`__threaddata`,
simply access transaction data transparently through the :attr:`_threaddata`
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.
: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.
: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 rollbacked).
:attr:`read_security` and :attr:`write_security`, boolean flags telling if
read/write security is currently activated.
: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.
: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
"""
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(user.login.encode('UTF8'))
cnxprops = cnxprops or ConnectionProperties('inmemory')
self.user = user
self.repo = repo
self.cnxtype = cnxprops.cnxtype
self.timestamp = time()
self.default_mode = 'read'
# support undo for Create Update Delete entity / Add Remove relation
if repo.config.creating or repo.config.repairing or self.is_internal_session:
self.undo_actions = ()
else:
self.undo_actions = set(repo.config['undo-support'].upper())
if self.undo_actions - set('CUDAR'):
raise Exception('bad undo-support string in configuration')
# 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(cnxprops.lang)
# internals
self._tx_data = {}
self.__threaddata = threading.local()
self._threads_in_transaction = set()
self._closed = False
self._closed_lock = threading.Lock()
def __unicode__(self):
return '<%ssession %s (%s 0x%x)>' % (
self.cnxtype, unicode(self.user.login), self.id, id(self))
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
wether the connections set should be freed or not.
"""
return transaction(self, free_cnxset)
def set_tx_data(self, txid=None):
if txid is None:
txid = threading.currentThread().getName()
try:
self.__threaddata.txdata = self._tx_data[txid]
except KeyError:
self.__threaddata.txdata = self._tx_data[txid] = TransactionData(txid)
@property
def _threaddata(self):
try:
return self.__threaddata.txdata
except AttributeError:
self.set_tx_data()
return self.__threaddata.txdata
def hijack_user(self, user):
"""return a fake request/session using specified user"""
session = Session(user, self.repo)
threaddata = session._threaddata
threaddata.cnxset = self.cnxset
# we attributed a connections set, need to update ctx_count else it will be freed
# while undesired
threaddata.ctx_count = 1
# share pending_operations, else operation added in the hi-jacked
# session such as SendMailOp won't ever be processed
threaddata.pending_operations = self.pending_operations
# everything in transaction_data should be copied back but the entity
# type cache we don't want to avoid security pb
threaddata.transaction_data = self.transaction_data.copy()
threaddata.transaction_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 security_enabled(self, 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 security_enabled(self, 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 ######################################################
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 set_language(self, language):
"""i18n configuration for translation"""
language = language or self.user.property_value('ui.language')
try:
gettext, pgettext = self.vreg.config.translations[language]
self._ = self.__ = gettext
self.pgettext = pgettext
except KeyError:
language = self.vreg.property_value('ui.language')
try:
gettext, pgettext = self.vreg.config.translations[language]
self._ = self.__ = gettext
self.pgettext = pgettext
except KeyError:
self._ = self.__ = unicode
self.pgettext = lambda x, y: y
self.lang = language
def change_property(self, prop, value):
assert prop == 'lang' # this is the only one changeable property for now
self.set_language(value)
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.transaction_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.transaction_data.get('neweids', ())
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)]
# security control #########################################################
DEFAULT_SECURITY = object() # evaluated to true by design
def security_enabled(self, read=False, write=False):
return security_enabled(self, read=read, write=write)
def init_security(self, read, write):
if read is None:
oldread = None
else:
oldread = self.set_read_security(read)
if write is None:
oldwrite = None
else:
oldwrite = self.set_write_security(write)
self._threaddata.ctx_count += 1
return oldread, oldwrite
def reset_security(self, read, write):
txstore = self._threaddata
txstore.ctx_count -= 1
if txstore.ctx_count == 0:
self._clear_thread_storage(txstore)
else:
if read is not None:
self.set_read_security(read)
if write is not None:
self.set_write_security(write)
@property
def read_security(self):
"""return a boolean telling if read security is activated or not"""
txstore = self._threaddata
if txstore is None:
return self.DEFAULT_SECURITY
try:
return txstore.read_security
except AttributeError:
txstore.read_security = self.DEFAULT_SECURITY
return txstore.read_security
def set_read_security(self, activated):
"""[de]activate read security, returning the previous value set for
later restoration.
you should usually use the `security_enabled` context manager instead
of this to change security settings.
"""
txstore = self._threaddata
if txstore is None:
return self.DEFAULT_SECURITY
oldmode = getattr(txstore, 'read_security', self.DEFAULT_SECURITY)
txstore.read_security = activated
# 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 dbapi_query to true when we go back to DEFAULT_SECURITY
txstore.dbapi_query = (oldmode is self.DEFAULT_SECURITY
or activated is self.DEFAULT_SECURITY)
return oldmode
@property
def write_security(self):
"""return a boolean telling if write security is activated or not"""
txstore = self._threaddata
if txstore is None:
return self.DEFAULT_SECURITY
try:
return txstore.write_security
except AttributeError:
txstore.write_security = self.DEFAULT_SECURITY
return txstore.write_security
def set_write_security(self, activated):
"""[de]activate write security, returning the previous value set for
later restoration.
you should usually use the `security_enabled` context manager instead
of this to change security settings.
"""
txstore = self._threaddata
if txstore is None:
return self.DEFAULT_SECURITY
oldmode = getattr(txstore, 'write_security', self.DEFAULT_SECURITY)
txstore.write_security = activated
return oldmode
@property
def running_dbapi_query(self):
"""return a boolean telling if it's triggered by a db-api query or by
a session query.
To be used in hooks, else may have a wrong value.
"""
return getattr(self._threaddata, 'dbapi_query', True)
# hooks activation control #################################################
# all hooks should be activated during normal execution
HOOKS_ALLOW_ALL = object()
HOOKS_DENY_ALL = object()
def allow_all_hooks_but(self, *categories):
return hooks_control(self, self.HOOKS_ALLOW_ALL, *categories)
def deny_all_hooks_but(self, *categories):
return hooks_control(self, self.HOOKS_DENY_ALL, *categories)
@property
def hooks_mode(self):
return getattr(self._threaddata, 'hooks_mode', self.HOOKS_ALLOW_ALL)
def set_hooks_mode(self, mode):
assert mode is self.HOOKS_ALLOW_ALL or mode is self.HOOKS_DENY_ALL
oldmode = getattr(self._threaddata, 'hooks_mode', self.HOOKS_ALLOW_ALL)
self._threaddata.hooks_mode = mode
return oldmode
def init_hooks_mode_categories(self, mode, categories):
oldmode = self.set_hooks_mode(mode)
if mode is self.HOOKS_DENY_ALL:
changes = self.enable_hook_categories(*categories)
else:
changes = self.disable_hook_categories(*categories)
self._threaddata.ctx_count += 1
return oldmode, changes
def reset_hooks_mode_categories(self, oldmode, mode, categories):
txstore = self._threaddata
txstore.ctx_count -= 1
if txstore.ctx_count == 0:
self._clear_thread_storage(txstore)
else:
try:
if categories:
if mode is self.HOOKS_DENY_ALL:
return self.disable_hook_categories(*categories)
else:
return self.enable_hook_categories(*categories)
finally:
self.set_hooks_mode(oldmode)
@property
def disabled_hook_categories(self):
try:
return getattr(self._threaddata, 'disabled_hook_cats')
except AttributeError:
cats = self._threaddata.disabled_hook_cats = set()
return cats
@property
def enabled_hook_categories(self):
try:
return getattr(self._threaddata, 'enabled_hook_cats')
except AttributeError:
cats = self._threaddata.enabled_hook_cats = set()
return cats
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()
if self.hooks_mode is self.HOOKS_DENY_ALL:
enabledcats = self.enabled_hook_categories
for category in categories:
if category in enabledcats:
enabledcats.remove(category)
changes.add(category)
else:
disabledcats = self.disabled_hook_categories
for category in categories:
if category not in disabledcats:
disabledcats.add(category)
changes.add(category)
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()
if self.hooks_mode is self.HOOKS_DENY_ALL:
enabledcats = self.enabled_hook_categories
for category in categories:
if category not in enabledcats:
enabledcats.add(category)
changes.add(category)
else:
disabledcats = self.disabled_hook_categories
for category in categories:
if category in disabledcats:
disabledcats.remove(category)
changes.add(category)
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 self.HOOKS_DENY_ALL:
return category in self.enabled_hook_categories
return category not in self.disabled_hook_categories
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)
# 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'
def get_mode(self):
return getattr(self._threaddata, 'mode', self.default_mode)
def set_mode(self, value):
self._threaddata.mode = value
mode = property(get_mode, set_mode,
doc='transaction mode (read/write/transaction), resetted to'
' default_mode on commit / rollback')
def get_commit_state(self):
return getattr(self._threaddata, 'commit_state', None)
def set_commit_state(self, value):
self._threaddata.commit_state = value
commit_state = property(get_commit_state, set_commit_state)
@property
def cnxset(self):
"""connections set, set according to transaction mode for each query"""
if self._closed:
self.free_cnxset(True)
raise Exception('try to access connections set on a closed session %s' % self.id)
return getattr(self._threaddata, 'cnxset', None)
def set_cnxset(self):
"""the session need a connections set to execute some queries"""
with self._closed_lock:
if self._closed:
self.free_cnxset(True)
raise Exception('try to set connections set on a closed session %s' % self.id)
if self.cnxset is None:
# get connections set first to avoid race-condition
self._threaddata.cnxset = cnxset = self.repo._get_cnxset()
self._threaddata.ctx_count += 1
try:
cnxset.cnxset_set()
except Exception:
self._threaddata.cnxset = None
self.repo._free_cnxset(cnxset)
raise
self._threads_in_transaction.add(
(threading.currentThread(), cnxset) )
return self._threaddata.cnxset
def _free_thread_cnxset(self, thread, cnxset, force_close=False):
try:
self._threads_in_transaction.remove( (thread, cnxset) )
except KeyError:
# race condition on cnxset freeing (freed by commit or rollback vs
# close)
pass
else:
if force_close:
cnxset.reconnect()
else:
cnxset.cnxset_freed()
# free cnxset once everything is done to avoid race-condition
self.repo._free_cnxset(cnxset)
def free_cnxset(self, ignoremode=False):
"""the session 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 = getattr(self._threaddata, 'cnxset', None)
if cnxset is not None and (ignoremode or self.mode == 'read'):
# even in read mode, we must release the current transaction
self._free_thread_cnxset(threading.currentThread(), cnxset)
del self._threaddata.cnxset
self._threaddata.ctx_count -= 1
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 transaction_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.transaction_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.transaction_data[key] = value
else:
self.data[key] = value
# request interface #######################################################
@property
def cursor(self):
"""return a rql cursor"""
return self
def set_entity_cache(self, entity):
# XXX session 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
try:
self.transaction_data['ecache'].setdefault(entity.eid, entity)
except KeyError:
self.transaction_data['ecache'] = ecache = {}
ecache[entity.eid] = entity
def entity_cache(self, eid):
return self.transaction_data['ecache'][eid]
def cached_entities(self):
return self.transaction_data.get('ecache', {}).values()
def drop_entity_cache(self, eid=None):
if eid is None:
self.transaction_data.pop('ecache', None)
else:
del self.transaction_data['ecache'][eid]
def from_controller(self):
"""return the id (string) of the controller issuing the request (no
sense here, always return 'view')
"""
return 'view'
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]
# db-api like interface ###################################################
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)
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:
txstore = self.__threaddata.txdata
except AttributeError:
pass
else:
if free_cnxset:
self.free_cnxset()
if txstore.ctx_count == 0:
self._clear_thread_storage(txstore)
else:
self._clear_tx_storage(txstore)
else:
self._clear_tx_storage(txstore)
def _clear_thread_storage(self, txstore):
self._tx_data.pop(txstore.transactionid, None)
try:
del self.__threaddata.txdata
except AttributeError:
pass
def _clear_tx_storage(self, txstore):
for name in ('commit_state', 'transaction_data',
'pending_operations', '_rewriter',
'pruned_hooks_cache'):
try:
delattr(txstore, name)
except AttributeError:
continue
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 rollbacked')
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
try:
# by default, operations are executed with security turned off
with security_enabled(self, False, False):
processed = []
self.commit_state = 'precommit'
try:
while self.pending_operations:
operation = self.pending_operations.pop(0)
operation.processed = 'precommit'
processed.append(operation)
operation.handle_event('precommit_event')
self.pending_operations[:] = processed
self.debug('precommit session %s done', self.id)
except BaseException:
# 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
for operation in reversed(processed):
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
self.cnxset.commit()
self.commit_state = 'postcommit'
while self.pending_operations:
operation = self.pending_operations.pop(0)
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 = getattr(self._threaddata, 'cnxset', None)
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 security_enabled(self, 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"""
with self._closed_lock:
self._closed = True
# copy since _threads_in_transaction maybe modified while waiting
for thread, cnxset in self._threads_in_transaction.copy():
if thread is threading.currentThread():
continue
self.info('waiting for thread %s', thread)
# do this loop/break instead of a simple join(10) in case thread is
# the main thread (in which case it will be removed from
# self._threads_in_transaction but still be alive...)
for i in xrange(10):
thread.join(1)
if not (thread.isAlive() and
(thread, cnxset) in self._threads_in_transaction):
break
else:
self.error('thread %s still alive after 10 seconds, will close '
'session anyway', thread)
self._free_thread_cnxset(thread, cnxset, force_close=True)
self.rollback()
del self.__threaddata
del self._tx_data
@property
def closed(self):
return not hasattr(self, '_tx_data')
# transaction data/operations management ##################################
@property
def transaction_data(self):
try:
return self._threaddata.transaction_data
except AttributeError:
self._threaddata.transaction_data = {}
return self._threaddata.transaction_data
@property
def pending_operations(self):
try:
return self._threaddata.pending_operations
except AttributeError:
self._threaddata.pending_operations = []
return self._threaddata.pending_operations
@property
def pruned_hooks_cache(self):
try:
return self._threaddata.pruned_hooks_cache
except AttributeError:
self._threaddata.pruned_hooks_cache = {}
return self._threaddata.pruned_hooks_cache
def add_operation(self, operation, index=None):
"""add an operation"""
if index is None:
self.pending_operations.append(operation)
else:
self.pending_operations.insert(index, operation)
# undo support ############################################################
def undoable_action(self, action, ertype):
return action in self.undo_actions and not ertype in NO_UNDO_TYPES
# XXX elif transaction on mark it partial
def transaction_uuid(self, set=True):
try:
return self.transaction_data['tx_uuid']
except KeyError:
if not set:
return
self.transaction_data['tx_uuid'] = uuid = uuid4().hex
self.repo.system_source.start_undoable_transaction(self, uuid)
return uuid
def transaction_inc_action_counter(self):
num = self.transaction_data.setdefault('tx_action_count', 0) + 1
self.transaction_data['tx_action_count'] = num
return num
# querier helpers #########################################################
@property
def rql_rewriter(self):
# in thread local storage since the rewriter isn't thread safe
try:
return self._threaddata._rewriter
except AttributeError:
self._threaddata._rewriter = RQLRewriter(self)
return self._threaddata._rewriter
def build_description(self, rqlst, args, result):
"""build a description for a given result"""
if len(rqlst.children) == 1 and len(rqlst.children[0].solutions) == 1:
# easy, all lines are identical
selected = rqlst.children[0].selection
solution = rqlst.children[0].solutions[0]
description = _make_description(selected, args, solution)
return RepeatList(len(result), tuple(description))
# hard, delegate the work :o)
return self.manual_build_descr(rqlst, args, result)
def manual_build_descr(self, rqlst, args, result):
"""build a description for a given result by analysing each row
XXX could probably be done more efficiently during execution of query
"""
# not so easy, looks for variable which changes from one solution
# to another
unstables = rqlst.get_variable_indices()
basedescr = []
todetermine = []
sampleselect = rqlst.children[0]
samplesols = sampleselect.solutions[0]
for i, term in enumerate(sampleselect.selection):
try:
ttype = term.get_type(samplesols, args)
except CoercionError:
ttype = None
isfinal = True
else:
if ttype is None or ttype == 'Any':
ttype = None
isfinal = True
else:
isfinal = ttype in BASE_TYPES
if ttype is None or i in unstables:
basedescr.append(None)
todetermine.append( (i, isfinal) )
else:
basedescr.append(ttype)
if not todetermine:
return RepeatList(len(result), tuple(basedescr))
return self._build_descr(result, basedescr, todetermine)
def _build_descr(self, result, basedescription, todetermine):
description = []
etype_from_eid = self.describe
todel = []
for i, row in enumerate(result):
row_descr = basedescription[:]
for index, isfinal in todetermine:
value = row[index]
if value is None:
# None value inserted by an outer join, no type
row_descr[index] = None
continue
if isfinal:
row_descr[index] = etype_from_pyobj(value)
else:
try:
row_descr[index] = etype_from_eid(value)[0]
except UnknownEid:
self.error('wrong eid %s in repository, you should '
'db-check the database' % value)
todel.append(i)
break
else:
description.append(tuple(row_descr))
for i in reversed(todel):
del result[i]
return description
# 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()
@deprecated("[3.7] execute is now unsafe by default in hooks/operation. You"
" can also control security with the security_enabled context "
"manager")
def unsafe_execute(self, rql, kwargs=None, eid_key=None, build_descr=True,
propagate=False):
"""like .execute but with security checking disabled (this method is
internal to the server, it's not part of the db-api)
"""
with security_enabled(self, read=False, write=False):
return self.execute(rql, kwargs, eid_key, build_descr)
@property
@deprecated("[3.7] is_super_session is deprecated, test "
"session.read_security and or session.write_security")
def is_super_session(self):
return not self.read_security or not self.write_security
@deprecated("[3.7] session is actual session")
def actual_session(self):
"""return the original parent session if any, else self"""
return self
@property
@deprecated("[3.6] use session.vreg.schema")
def schema(self):
return self.repo.schema
@deprecated("[3.4] use vreg['etypes'].etype_class(etype)")
def etype_class(self, etype):
"""return an entity class for the given entity type"""
return self.vreg['etypes'].etype_class(etype)
@deprecated('[3.4] use direct access to session.transaction_data')
def query_data(self, key, default=None, setdefault=False, pop=False):
if setdefault:
assert not pop
return self.transaction_data.setdefault(key, default)
if pop:
return self.transaction_data.pop(key, default)
else:
return self.transaction_data.get(key, default)
@deprecated('[3.4] use entity_from_eid(eid, etype=None)')
def entity(self, eid):
"""return a result set for the given eid"""
return self.entity_from_eid(eid)
# 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
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
self.cnxtype = 'inmemory'
if not safe:
self.disable_hook_categories('integrity')
@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 getattr(self._threaddata, 'cnxset', None)
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 has_permission(self, pname, contexteid=None):
return True
def property_value(self, key):
if key == 'ui.language':
return 'en'
return None
from logging import getLogger
from cubicweb import set_log_methods
set_log_methods(Session, getLogger('cubicweb.session'))