"""Adapter for google appengine source.
:organization: Logilab
:copyright: 2008 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
"""
__docformat__ = "restructuredtext en"
from logilab.common.decorators import cached, clear_cache
from cubicweb import AuthenticationError, UnknownEid, server
from cubicweb.server.sources import AbstractSource, ConnectionWrapper
from cubicweb.server.pool import SingleOperation
from cubicweb.server.utils import crypt_password
from cubicweb.goa.dbinit import set_user_groups
from cubicweb.goa.rqlinterpreter import RQLInterpreter
from google.appengine.api.datastore import Key, Entity, Get, Put, Delete
from google.appengine.api.datastore import Query
from google.appengine.api import datastore_errors, users
def _init_groups(guser, euser):
# set default groups
if guser is None:
groups = ['guests']
else:
groups = ['users']
if users.is_current_user_admin():
groups.append('managers')
set_user_groups(euser, groups)
def _clear_related_cache(session, gaesubject, rtype, gaeobject):
subject, object = str(gaesubject.key()), str(gaeobject.key())
for eid, role in ((subject, 'subject'), (object, 'object')):
# clear related cache if necessary
try:
entity = session.entity_cache(eid)
except KeyError:
pass
else:
entity.clear_related_cache(rtype, role)
if gaesubject.kind() == 'EUser':
for asession in session.repo._sessions.itervalues():
if asession.user.eid == subject:
asession.user.clear_related_cache(rtype, 'subject')
if gaeobject.kind() == 'EUser':
for asession in session.repo._sessions.itervalues():
if asession.user.eid == object:
asession.user.clear_related_cache(rtype, 'object')
def _mark_modified(session, gaeentity):
modified = session.query_data('modifiedentities', {}, setdefault=True)
modified[str(gaeentity.key())] = gaeentity
DatastorePutOp(session)
def _rinfo(session, subject, rtype, object):
gaesubj = session.datastore_get(subject)
gaeobj = session.datastore_get(object)
rschema = session.vreg.schema.rschema(rtype)
cards = rschema.rproperty(gaesubj.kind(), gaeobj.kind(), 'cardinality')
return gaesubj, gaeobj, cards
def _radd(session, gaeentity, targetkey, relation, card):
if card in '?1':
gaeentity[relation] = targetkey
else:
try:
related = gaeentity[relation]
except KeyError:
related = []
else:
if related is None:
related = []
related.append(targetkey)
gaeentity[relation] = related
_mark_modified(session, gaeentity)
def _rdel(session, gaeentity, targetkey, relation, card):
if card in '?1':
gaeentity[relation] = None
else:
related = gaeentity[relation]
if related is not None:
related = [key for key in related if not key == targetkey]
gaeentity[relation] = related or None
_mark_modified(session, gaeentity)
class DatastorePutOp(SingleOperation):
"""delayed put of entities to have less datastore write api calls
* save all modified entities at precommit (should be the first operation
processed, hence the 0 returned by insert_index())
* in case others precommit operations modify some entities, resave modified
entities at commit. This suppose that no db changes will occurs during
commit event but it should be the case.
"""
def insert_index(self):
return 0
def _put_entities(self):
pending = self.session.query_data('pendingeids', ())
modified = self.session.query_data('modifiedentities', {})
for eid, gaeentity in modified.iteritems():
assert not eid in pending
Put(gaeentity)
modified.clear()
def commit_event(self):
self._put_entities()
def precommit_event(self):
self._put_entities()
class GAESource(AbstractSource):
"""adapter for a system source on top of google appengine datastore"""
passwd_rql = "Any P WHERE X is EUser, X login %(login)s, X upassword P"
auth_rql = "Any X WHERE X is EUser, X login %(login)s, X upassword %(pwd)s"
_sols = ({'X': 'EUser', 'P': 'Password'},)
options = ()
def __init__(self, repo, appschema, source_config, *args, **kwargs):
AbstractSource.__init__(self, repo, appschema, source_config,
*args, **kwargs)
if repo.config['use-google-auth']:
self.info('using google authentication service')
self.authenticate = self.authenticate_gauth
else:
self.authenticate = self.authenticate_local
def reset_caches(self):
"""method called during test to reset potential source caches"""
pass
def init_creating(self):
pass
def init(self):
# XXX unregister unsupported hooks
from cubicweb.server.hooks import sync_owner_after_add_composite_relation
self.repo.hm.unregister_hook(sync_owner_after_add_composite_relation,
'after_add_relation', '')
def get_connection(self):
return ConnectionWrapper()
# ISource interface #######################################################
def compile_rql(self, rql):
rqlst = self.repo.querier._rqlhelper.parse(rql)
rqlst.restricted_vars = ()
rqlst.children[0].solutions = self._sols
return rqlst
def set_schema(self, schema):
"""set the application'schema"""
self.interpreter = RQLInterpreter(schema)
self.schema = schema
if 'EUser' in schema and not self.repo.config['use-google-auth']:
# rql syntax trees used to authenticate users
self._passwd_rqlst = self.compile_rql(self.passwd_rql)
self._auth_rqlst = self.compile_rql(self.auth_rql)
def support_entity(self, etype, write=False):
"""return true if the given entity's type is handled by this adapter
if write is true, return true only if it's a RW support
"""
return True
def support_relation(self, rtype, write=False):
"""return true if the given relation's type is handled by this adapter
if write is true, return true only if it's a RW support
"""
return True
def authenticate_gauth(self, session, login, password):
guser = users.get_current_user()
# allowing or not anonymous connection should be done in the app.yaml
# file, suppose it's authorized if we are there
if guser is None:
login = u'anonymous'
else:
login = unicode(guser.nickname())
# XXX http://code.google.com/appengine/docs/users/userobjects.html
# use a reference property to automatically work with email address
# changes after the propagation feature is implemented
key = Key.from_path('EUser', 'key_' + login, parent=None)
try:
euser = session.datastore_get(key)
# XXX fix user. Required until we find a better way to fix broken records
if not euser.get('s_in_group'):
_init_groups(guser, euser)
Put(euser)
return str(key)
except datastore_errors.EntityNotFoundError:
# create a record for this user
euser = Entity('EUser', name='key_' + login)
euser['s_login'] = login
_init_groups(guser, euser)
Put(euser)
return str(euser.key())
def authenticate_local(self, session, login, password):
"""return EUser eid for the given login/password if this account is
defined in this source, else raise `AuthenticationError`
two queries are needed since passwords are stored crypted, so we have
to fetch the salt first
"""
args = {'login': login, 'pwd' : password}
if password is not None:
rset = self.syntax_tree_search(session, self._passwd_rqlst, args)
try:
pwd = rset[0][0]
except IndexError:
raise AuthenticationError('bad login')
# passwords are stored using the bytea type, so we get a StringIO
if pwd is not None:
args['pwd'] = crypt_password(password, pwd[:2])
# get eid from login and (crypted) password
rset = self.syntax_tree_search(session, self._auth_rqlst, args)
try:
return rset[0][0]
except IndexError:
raise AuthenticationError('bad password')
def syntax_tree_search(self, session, union, args=None, cachekey=None,
varmap=None):
"""return result from this source for a rql query (actually from a rql
syntax tree and a solution dictionary mapping each used variable to a
possible type). If cachekey is given, the query necessary to fetch the
results (but not the results themselves) may be cached using this key.
"""
results, description = self.interpreter.interpret(union, args,
session.datastore_get)
return results # XXX description
def flying_insert(self, table, session, union, args=None, varmap=None):
raise NotImplementedError
def add_entity(self, session, entity):
"""add a new entity to the source"""
# do not delay add_entity as other modifications, new created entity
# needs an eid
entity.put()
def update_entity(self, session, entity):
"""replace an entity in the source"""
gaeentity = entity.to_gae_model()
_mark_modified(session, entity.to_gae_model())
if gaeentity.kind() == 'EUser':
for asession in self.repo._sessions.itervalues():
if asession.user.eid == entity.eid:
asession.user.update(dict(gaeentity))
def delete_entity(self, session, etype, eid):
"""delete an entity from the source"""
# do not delay delete_entity as other modifications to ensure
# consistency
key = Key(eid)
Delete(key)
session.clear_datastore_cache(key)
session.drop_entity_cache(eid)
session.query_data('modifiedentities', {}).pop(eid, None)
def add_relation(self, session, subject, rtype, object):
"""add a relation to the source"""
gaesubj, gaeobj, cards = _rinfo(session, subject, rtype, object)
_radd(session, gaesubj, gaeobj.key(), 's_' + rtype, cards[0])
_radd(session, gaeobj, gaesubj.key(), 'o_' + rtype, cards[1])
_clear_related_cache(session, gaesubj, rtype, gaeobj)
def delete_relation(self, session, subject, rtype, object):
"""delete a relation from the source"""
gaesubj, gaeobj, cards = _rinfo(session, subject, rtype, object)
pending = session.query_data('pendingeids', set(), setdefault=True)
if not subject in pending:
_rdel(session, gaesubj, gaeobj.key(), 's_' + rtype, cards[0])
if not object in pending:
_rdel(session, gaeobj, gaesubj.key(), 'o_' + rtype, cards[1])
_clear_related_cache(session, gaesubj, rtype, gaeobj)
# system source interface #################################################
def eid_type_source(self, session, eid):
"""return a tuple (type, source, extid) for the entity with id <eid>"""
try:
key = Key(eid)
except datastore_errors.BadKeyError:
raise UnknownEid(eid)
return key.kind(), 'system', None
def create_eid(self, session):
return None # let the datastore generating key
def add_info(self, session, entity, source, extid=None):
"""add type and source info for an eid into the system table"""
pass
def delete_info(self, session, eid, etype, uri, extid):
"""delete system information on deletion of an entity by transfering
record from the entities table to the deleted_entities table
"""
pass
def fti_unindex_entity(self, session, eid):
"""remove text content for entity with the given eid from the full text
index
"""
pass
def fti_index_entity(self, session, entity):
"""add text content of a created/modified entity to the full text index
"""
pass