[web/json] an empty rset is just fine for ejsonexport
The ejsonexport view can just return an empty list for an empty rset.
Closes #4005518
# copyright 2013-2013 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/>.
"""Official API to access the content of a repository
"""
from logilab.common.deprecation import deprecated
from cubicweb.utils import parse_repo_uri
from cubicweb import ConnectionError, ProgrammingError, AuthenticationError
from uuid import uuid4
from contextlib import contextmanager
from cubicweb.req import RequestSessionBase
from functools import wraps
### private function for specific method ############################
def _get_inmemory_repo(config, vreg=None):
from cubicweb.server.repository import Repository
from cubicweb.server.utils import TasksManager
return Repository(config, TasksManager(), vreg=vreg)
### public API ######################################################
def get_repository(uri=None, config=None, vreg=None):
"""get a repository for the given URI or config/vregistry (in case we're
loading the repository for a client, eg web server, configuration).
The returned repository may be an in-memory repository or a proxy object
using a specific RPC method, depending on the given URI (pyro or zmq).
"""
if uri is None:
return _get_inmemory_repo(config, vreg)
protocol, hostport, appid = parse_repo_uri(uri)
if protocol == 'inmemory':
# me may have been called with a dummy 'inmemory://' uri ...
return _get_inmemory_repo(config, vreg)
if protocol == 'pyroloc': # direct connection to the instance
from logilab.common.pyro_ext import get_proxy
uri = uri.replace('pyroloc', 'PYRO')
return get_proxy(uri)
if protocol == 'pyro': # connection mediated through the pyro ns
from logilab.common.pyro_ext import ns_get_proxy
path = appid.strip('/')
if not path:
raise ConnectionError(
"can't find instance name in %s (expected to be the path component)"
% uri)
if '.' in path:
nsgroup, nsid = path.rsplit('.', 1)
else:
nsgroup = 'cubicweb'
nsid = path
return ns_get_proxy(nsid, defaultnsgroup=nsgroup, nshost=hostport)
if protocol.startswith('zmqpickle-'):
from cubicweb.zmqclient import ZMQRepositoryClient
return ZMQRepositoryClient(uri)
else:
raise ConnectionError('unknown protocol: `%s`' % protocol)
def connect(repo, login, **kwargs):
"""Take credential and return associated ClientConnection.
The ClientConnection is associated to a new Session object that will be
closed when the ClientConnection is closed.
raise AuthenticationError if the credential are invalid."""
sessionid = repo.connect(login, **kwargs)
session = repo._get_session(sessionid)
# XXX the autoclose_session should probably be handle on the session directly
# this is something to consider once we have proper server side Connection.
return ClientConnection(session, autoclose_session=True)
def anonymous_cnx(repo):
"""return a ClientConnection for Anonymous user.
The ClientConnection is associated to a new Session object that will be
closed when the ClientConnection is closed.
raises an AuthenticationError if anonymous usage is not allowed
"""
anoninfo = getattr(repo.config, 'anonymous_user', lambda: None)()
if anoninfo is None: # no anonymous user
raise AuthenticationError('anonymous access is not authorized')
anon_login, anon_password = anoninfo
# use vreg's repository cache
return connect(repo, anon_login, password=anon_password)
def _srv_cnx_func(name):
"""Decorate ClientConnection method blindly forward to Connection
THIS TRANSITIONAL PURPOSE
will be dropped when we have standalone connection"""
def proxy(clt_cnx, *args, **kwargs):
# the ``with`` dance is transitional. We do not have Standalone
# Connection yet so we use this trick to unsure the session have the
# proper cnx loaded. This can be simplified one we have Standalone
# Connection object
if not clt_cnx._open:
raise ProgrammingError('Closed client connection')
return getattr(clt_cnx._cnx, name)(*args, **kwargs)
return proxy
def _open_only(func):
"""decorator for ClientConnection method that check it is open"""
@wraps(func)
def check_open(clt_cnx, *args, **kwargs):
if not clt_cnx._open:
raise ProgrammingError('Closed client connection')
return func(clt_cnx, *args, **kwargs)
return check_open
class ClientConnection(RequestSessionBase):
"""A Connection object to be used Client side.
This object is aimed to be used client side (so potential communication
with the repo through RPC) and aims to offer some compatibility with the
cubicweb.dbapi.Connection interface.
The autoclose_session parameter informs the connection that this session
has been opened explicitly and only for this client connection. The
connection will close the session on exit.
"""
# make exceptions available through the connection object
ProgrammingError = ProgrammingError
# attributes that may be overriden per connection instance
anonymous_connection = False # XXX really needed ?
is_repo_in_memory = True # BC, always true
def __init__(self, session, autoclose_session=False):
super(ClientConnection, self).__init__(session.vreg)
self._session = session # XXX there is no real reason to keep the
# session around function still using it should
# be rewritten and migrated.
self._cnx = None
self._open = None
self._web_request = False
#: cache entities built during the connection
self._eid_cache = {}
self._set_user(session.user)
self._autoclose_session = autoclose_session
def __enter__(self):
assert self._open is None
self._open = True
self._cnx = self._session.new_cnx()
self._cnx.__enter__()
self._cnx.ctx_count += 1
return self
def __exit__(self, exc_type, exc_val, exc_tb):
self._open = False
self._cnx.ctx_count -= 1
self._cnx.__exit__(exc_type, exc_val, exc_tb)
self._cnx = None
if self._autoclose_session:
# we have to call repo.close to ensure the repo properly forgets the
# session; calling session.close() is not enough :-(
self._session.repo.close(self._session.sessionid)
# begin silly BC
@property
def _closed(self):
return not self._open
def close(self):
if self._open:
self.__exit__(None, None, None)
def __repr__(self):
# XXX we probably want to reference the user of the session here
if self._open is None:
return '<ClientConnection (not open yet)>'
elif not self._open:
return '<ClientConnection (closed)>'
elif self.anonymous_connection:
return '<ClientConnection %s (anonymous)>' % self._cnx.connectionid
else:
return '<ClientConnection %s>' % self._cnx.connectionid
# end silly BC
# Main Connection purpose in life #########################################
call_service = _srv_cnx_func('call_service')
@_open_only
def execute(self, *args, **kwargs):
# the ``with`` dance is transitional. We do not have Standalone
# Connection yet so we use this trick to unsure the session have the
# proper cnx loaded. This can be simplified one we have Standalone
# Connection object
rset = self._cnx.execute(*args, **kwargs)
rset.req = self
# XXX keep the same behavior as the old dbapi
# otherwise multiple tests break.
# The little internet kitten is very sad about this situation.
rset._rqlst = None
return rset
@_open_only
def commit(self, *args, **kwargs):
try:
return self._cnx.commit(*args, **kwargs)
finally:
self.drop_entity_cache()
@_open_only
def rollback(self, *args, **kwargs):
try:
return self._cnx.rollback(*args, **kwargs)
finally:
self.drop_entity_cache()
# security #################################################################
allow_all_hooks_but = _srv_cnx_func('allow_all_hooks_but')
deny_all_hooks_but = _srv_cnx_func('deny_all_hooks_but')
security_enabled = _srv_cnx_func('security_enabled')
# direct sql ###############################################################
system_sql = _srv_cnx_func('system_sql')
# session data methods #####################################################
get_shared_data = _srv_cnx_func('get_shared_data')
set_shared_data = _srv_cnx_func('set_shared_data')
@property
def transaction_data(self):
return self._cnx.transaction_data
# meta-data accessors ######################################################
@_open_only
def source_defs(self):
"""Return the definition of sources used by the repository."""
return self._session.repo.source_defs()
@_open_only
def get_schema(self):
"""Return the schema currently used by the repository."""
return self._session.repo.source_defs()
@_open_only
def get_option_value(self, option):
"""Return the value for `option` in the configuration."""
return self._session.repo.get_option_value(option)
entity_metas = _srv_cnx_func('entity_metas')
describe = _srv_cnx_func('describe') # XXX deprecated in 3.19
# undo support ############################################################
@_open_only
def undoable_transactions(self, ueid=None, req=None, **actionfilters):
"""Return a list of undoable transaction objects by the connection's
user, ordered by descendant transaction time.
Managers may filter according to user (eid) who has done the transaction
using the `ueid` argument. Others will only see their own transactions.
Additional filtering capabilities is provided by using the following
named arguments:
* `etype` to get only transactions creating/updating/deleting entities
of the given type
* `eid` to get only transactions applied to entity of the given eid
* `action` to get only transactions doing the given action (action in
'C', 'U', 'D', 'A', 'R'). If `etype`, action can only be 'C', 'U' or
'D'.
* `public`: when additional filtering is provided, their are by default
only searched in 'public' actions, unless a `public` argument is given
and set to false.
"""
# the ``with`` dance is transitional. We do not have Standalone
# Connection yet so we use this trick to unsure the session have the
# proper cnx loaded. This can be simplified one we have Standalone
# Connection object
source = self._cnx.repo.system_source
txinfos = source.undoable_transactions(self._cnx, ueid, **actionfilters)
for txinfo in txinfos:
txinfo.req = req or self # XXX mostly wrong
return txinfos
@_open_only
def transaction_info(self, txuuid, req=None):
"""Return transaction object for the given uid.
raise `NoSuchTransaction` if not found or if session's user is not
allowed (eg not in managers group and the transaction doesn't belong to
him).
"""
# the ``with`` dance is transitional. We do not have Standalone
# Connection yet so we use this trick to unsure the session have the
# proper cnx loaded. This can be simplified one we have Standalone
# Connection object
txinfo = self._cnx.repo.system_source.tx_info(self._cnx, txuuid)
if req:
txinfo.req = req
else:
txinfo.cnx = self
return txinfo
@_open_only
def transaction_actions(self, txuuid, public=True):
"""Return an ordered list of action effectued during that transaction.
If public is true, return only 'public' actions, eg not ones triggered
under the cover by hooks, else return all actions.
raise `NoSuchTransaction` if the transaction is not found or if
session's user is not allowed (eg not in managers group and the
transaction doesn't belong to him).
"""
# the ``with`` dance is transitional. We do not have Standalone
# Connection yet so we use this trick to unsure the session have the
# proper cnx loaded. This can be simplified one we have Standalone
# Connection object
return self._cnx.repo.system_source.tx_actions(self._cnx, txuuid, public)
@_open_only
def undo_transaction(self, txuuid):
"""Undo the given transaction. Return potential restoration errors.
raise `NoSuchTransaction` if not found or if session's user is not
allowed (eg not in managers group and the transaction doesn't belong to
him).
"""
# the ``with`` dance is transitional. We do not have Standalone
# Connection yet so we use this trick to unsure the session have the
# proper cnx loaded. This can be simplified one we have Standalone
# Connection object
return self._cnx.repo.system_source.undo_transaction(self._cnx, txuuid)
# cache management
def entity_cache(self, eid):
return self._eid_cache[eid]
def set_entity_cache(self, entity):
self._eid_cache[entity.eid] = entity
def cached_entities(self):
return self._eid_cache.values()
def drop_entity_cache(self, eid=None):
if eid is None:
self._eid_cache = {}
else:
del self._eid_cache[eid]
# deprecated stuff
@deprecated('[3.19] This is a repoapi.ClientConnection object not a dbapi one')
def request(self):
return self
@deprecated('[3.19] This is a repoapi.ClientConnection object not a dbapi one')
def cursor(self):
return self
@property
@deprecated('[3.19] This is a repoapi.ClientConnection object not a dbapi one')
def sessionid(self):
return self._session.sessionid
@property
@deprecated('[3.19] This is a repoapi.ClientConnection object not a dbapi one')
def connection(self):
return self
@property
@deprecated('[3.19] This is a repoapi.ClientConnection object not a dbapi one')
def _repo(self):
return self._session.repo