# copyright 2010-2011 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/>.
"""datafeed sources: copy data from an external data stream into the system
database
"""
from datetime import datetime, timedelta
from base64 import b64decode
from cubicweb import RegistryNotFound, ObjectNotFound, ValidationError
from cubicweb.server.sources import AbstractSource
from cubicweb.appobject import AppObject
class DataFeedSource(AbstractSource):
copy_based_source = True
options = (
('synchronize',
{'type' : 'yn',
'default': True,
'help': ('Is the repository responsible to automatically import '
'content from this source? '
'You should say yes unless you don\'t want this behaviour '
'or if you use a multiple repositories setup, in which '
'case you should say yes on one repository, no on others.'),
'group': 'datafeed-source', 'level': 2,
}),
('synchronization-interval',
{'type' : 'time',
'default': '5min',
'help': ('Interval in seconds between synchronization with the '
'external source (default to 5 minutes, must be >= 1 min).'),
'group': 'datafeed-source', 'level': 2,
}),
('delete-entities',
{'type' : 'yn',
'default': True,
'help': ('Should already imported entities not found anymore on the '
'external source be deleted?'),
'group': 'datafeed-source', 'level': 2,
}),
)
def __init__(self, repo, source_config, eid=None):
AbstractSource.__init__(self, repo, source_config, eid)
self.update_config(None, self.check_conf_dict(eid, source_config,
fail_if_unknown=False))
def check_config(self, source_entity):
"""check configuration of source entity"""
typedconfig = super(DataFeedSource, self).check_config(source_entity)
if typedconfig['synchronization-interval'] < 60:
_ = source_entity._cw._
msg = _('synchronization-interval must be greater than 1 minute')
raise ValidationError(source_entity.eid, {'config': msg})
return typedconfig
def _entity_update(self, source_entity):
source_entity.complete()
self.parser = source_entity.parser
self.latest_retrieval = source_entity.latest_retrieval
self.urls = [url.strip() for url in source_entity.url.splitlines()
if url.strip()]
def update_config(self, source_entity, typedconfig):
"""update configuration from source entity. `typedconfig` is config
properly typed with defaults set
"""
self.synchro_interval = timedelta(seconds=typedconfig['synchronization-interval'])
if source_entity is not None:
self._entity_update(source_entity)
self.config = typedconfig
def init(self, activated, source_entity):
if activated:
self._entity_update(source_entity)
self.parser = source_entity.parser
self.load_mapping(source_entity._cw)
def _get_parser(self, session, **kwargs):
return self.repo.vreg['parsers'].select(
self.parser, session, source=self, **kwargs)
def load_mapping(self, session):
self.mapping = {}
self.mapping_idx = {}
try:
parser = self._get_parser(session)
except (RegistryNotFound, ObjectNotFound):
return # no parser yet, don't go further
self._load_mapping(session, parser=parser)
def add_schema_config(self, schemacfg, checkonly=False, parser=None):
"""added CWSourceSchemaConfig, modify mapping accordingly"""
if parser is None:
parser = self._get_parser(schemacfg._cw)
parser.add_schema_config(schemacfg, checkonly)
def del_schema_config(self, schemacfg, checkonly=False, parser=None):
"""deleted CWSourceSchemaConfig, modify mapping accordingly"""
if parser is None:
parser = self._get_parser(schemacfg._cw)
parser.del_schema_config(schemacfg, checkonly)
def fresh(self):
if self.latest_retrieval is None:
return False
return datetime.utcnow() < (self.latest_retrieval + self.synchro_interval)
def pull_data(self, session, force=False, raise_on_error=False):
if not force and self.fresh():
return {}
if self.config['delete-entities']:
myuris = self.source_cwuris(session)
else:
myuris = None
parser = self._get_parser(session, sourceuris=myuris)
error = False
self.info('pulling data for source %s', self.uri)
for url in self.urls:
try:
if parser.process(url):
error = True
except IOError, exc:
if raise_on_error:
raise
self.error('could not pull data while processing %s: %s',
url, exc)
error = True
if error:
self.warning("some error occured, don't attempt to delete entities")
elif self.config['delete-entities'] and myuris:
byetype = {}
for eid, etype in myuris.values():
byetype.setdefault(etype, []).append(str(eid))
self.error('delete %s entities %s', self.uri, byetype)
for etype, eids in byetype.iteritems():
session.execute('DELETE %s X WHERE X eid IN (%s)'
% (etype, ','.join(eids)))
self.latest_retrieval = datetime.utcnow()
session.execute('SET X latest_retrieval %(date)s WHERE X eid %(x)s',
{'x': self.eid, 'date': self.latest_retrieval})
return parser.stats
def before_entity_insertion(self, session, lid, etype, eid, sourceparams):
"""called by the repository when an eid has been attributed for an
entity stored here but the entity has not been inserted in the system
table yet.
This method must return the an Entity instance representation of this
entity.
"""
entity = super(DataFeedSource, self).before_entity_insertion(
session, lid, etype, eid, sourceparams)
entity.cw_edited['cwuri'] = unicode(lid)
entity.cw_edited.set_defaults()
sourceparams['parser'].before_entity_copy(entity, sourceparams)
# avoid query to search full-text indexed attributes
for attr in entity.e_schema.indexable_attributes():
entity.cw_edited.setdefault(attr, u'')
return entity
def after_entity_insertion(self, session, lid, entity, sourceparams):
"""called by the repository after an entity stored here has been
inserted in the system table.
"""
if session.is_hook_category_activated('integrity'):
entity.cw_edited.check(creation=True)
self.repo.system_source.add_entity(session, entity)
entity.cw_edited.saved = entity._cw_is_saved = True
sourceparams['parser'].after_entity_copy(entity, sourceparams)
def source_cwuris(self, session):
sql = ('SELECT extid, eid, type FROM entities, cw_source_relation '
'WHERE entities.eid=cw_source_relation.eid_from '
'AND cw_source_relation.eid_to=%s' % self.eid)
return dict((b64decode(uri), (eid, type))
for uri, eid, type in session.system_sql(sql))
class DataFeedParser(AppObject):
__registry__ = 'parsers'
def __init__(self, session, source, sourceuris=None):
self._cw = session
self.source = source
self.sourceuris = sourceuris
self.stats = {'created': set(),
'updated': set()}
def add_schema_config(self, schemacfg, checkonly=False):
"""added CWSourceSchemaConfig, modify mapping accordingly"""
msg = schemacfg._cw._("this parser doesn't use a mapping")
raise ValidationError(schemacfg.eid, {None: msg})
def del_schema_config(self, schemacfg, checkonly=False):
"""deleted CWSourceSchemaConfig, modify mapping accordingly"""
msg = schemacfg._cw._("this parser doesn't use a mapping")
raise ValidationError(schemacfg.eid, {None: msg})
def extid2entity(self, uri, etype, **sourceparams):
sourceparams['parser'] = self
eid = self.source.extid2eid(str(uri), etype, self._cw,
sourceparams=sourceparams)
if self.sourceuris is not None:
self.sourceuris.pop(str(uri), None)
return self._cw.entity_from_eid(eid, etype)
def process(self, url):
"""main callback: process the url"""
raise NotImplementedError
def before_entity_copy(self, entity, sourceparams):
raise NotImplementedError
def after_entity_copy(self, entity, sourceparams):
self.stats['created'].add(entity.eid)
def created_during_pull(self, entity):
return entity.eid in self.stats['created']
def updated_during_pull(self, entity):
return entity.eid in self.stats['updated']
def notify_updated(self, entity):
return self.stats['updated'].add(entity.eid)