cubicweb_seda/xsd2entities.py
author Sylvain Thénault <sylvain.thenault@logilab.fr>
Tue, 12 Dec 2017 17:57:57 +0100
changeset 2915 451328134bee
parent 2899 ed666cbea6af
child 3021 2212adf2c673
permissions -rw-r--r--
[entities] Add a safety belt avoid unexpected error in some corner case e.g. while debugging an instance I attempted to display result of 'Any X, C WHERE X container C' with unexpectedly to container for the entity, but I wasn't able to display it because rset.one() raised an error since len(rset) was 2. Even if the caller may be wrong, it seems ok to not call rset.one() if function is called in an erroneous context and simply return None in such case.

# copyright 2016 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr -- mailto:contact@logilab.fr
#
# This program 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.
#
# This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
"""Generate CubicWeb's entities from XSD file"""

import json

from xsd2yams import MULTIPLE_CHILDREN, CodeGenerator
from xsd2uicfg import ordered_attributes

MULTIPLE_ETYPES = set(etype for etype, _ in MULTIPLE_CHILDREN)

TEMPLATE = '''class {etype}(SEDAAnyEntity):
    __regid__ = '{etype}'
    fetch_attrs, cw_fetch_order = fetch_config({attributes})
    value_attr = {value_attribute}
'''


class EntitiesGenerator(CodeGenerator):

    def _generate(self, mapping, stream):
        stream.write('from cubicweb.entities import AnyEntity, fetch_config\n\n')
        stream.write('''
class SEDAAnyEntity(AnyEntity):
    __abstract__ = True
    value_attr = None

    def dc_title(self):
        if self.value_attr is None:
            return self.dc_type()
        return self.printable_value(self.value_attr)


''')
        self.altetype2rtype = {}  # rtype to children elements for all choices
        self.check_card_etypes = set()  # entity types whose cardinality must be checked
        self.check_card_rtypes = set()  # relation types whose children cardinality must be checked
        for mapping_element in mapping.ordered:
            self._callback('register_alt_rtype_for', mapping_element)
            eclass_code = self._callback('entity_class_for', mapping_element)
            if eclass_code:
                stream.write(eclass_code + '\n')
        # Write pre-computed data structures as constants
        for name, data in [('CHOICE_RTYPE', self.altetype2rtype),
                           ('CHECK_CARD_ETYPES', sorted(self.check_card_etypes)),
                           ('CHECK_CHILDREN_CARD_RTYPES', sorted(self.check_card_rtypes))]:
            stream.write(u'{} = '.format(name))
            stream.write(json.dumps(data, sort_keys=True, indent=2,
                                    separators=(',', ': ')).replace('"', "'") + '\n')

    def entity_class_for_e_type_mapping(self, mapping):
        attributes = ordered_attributes(mapping)
        value_attribute = None
        if mapping.etype in ('SEDAArchiveUnit', 'SEDABinaryDataObject', 'SEDAPhysicalDataObject'):
            pass
        elif mapping.attributes:
            value_attribute = next(iter(mapping.attributes))
        elif mapping.cards and len(mapping.cards) > 1:
            attributes = ['user_cardinality']
        if mapping.etype in MULTIPLE_ETYPES:
            attributes.insert(0, 'ordering')
        return TEMPLATE.format(etype=mapping.etype,
                               attributes=attributes,
                               value_attribute=repr(value_attribute))

    def register_alt_rtype_for_rdef_mapping(self, mapping):
        composite = mapping.composite
        if not composite:
            return
        altetypes = mapping.objtypes if composite == 'object' else [mapping.subjtype]
        for altetype in altetypes:
            if altetype.startswith('SEDAAlt'):
                self.altetype2rtype.setdefault(altetype, []).append((mapping.rtype, composite))

        if mapping.card[1] in '*+':
            self.check_card_etypes.add(mapping.subjtype)
            self.check_card_rtypes.add(mapping.rtype)


if __name__ == '__main__':
    EntitiesGenerator.main()