sobjects/textparsers.py
author Aurelien Campeas <aurelien.campeas@logilab.fr>
Wed, 03 Jul 2013 14:33:27 +0200
branchstable
changeset 9130 0f1504a9fb51
parent 8748 f5027f8d2478
permissions -rw-r--r--
[constraint] more robust unicity constraint failures reporting for end-users Postgres or Sqlserver have limits on the index names (around resp. 64 and 128 characters). Because `logilab.database` encodes the `unique together` constraint rtypes in the index names, we sometimes get truncated index names, from which it is impossible to retrieve all rtypes. In the long run, the way such index are named should be changed. In the short term, we try to reduce the end-user confusion resulting from this design flaw: * in source/native, the regex filtering ``IntegrityError`` message does not impose an `_idx` suffix, which indeed may be absent (the result being an UI message that resembles a catastrophic failure), * also we avoid including a trailing " (double quote) from the error message * in entities/adapters, the well-named ``IUserFriendly`` adapter is made a bit smarter about how to handle missing rtypes. * the adapter also always produces a global message explaining the issue (and the fact that sometimes, the user is not shown all the relevant info) * i18n is updated Closes #2793789

# 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/>.
"""Some parsers to detect action to do from text

Currently only a parser to look for state change instruction is provided.
Take care to security when you're using it, think about the user that
will provide the text to analyze...
"""

__docformat__ = "restructuredtext en"

import re

from cubicweb import UnknownEid
from cubicweb.view import Component


class TextAnalyzer(Component):
    """analyze and extract information from plain text by calling registered
    text parsers
    """
    __regid__ = 'textanalyzer'

    def parse(self, caller, text):
        for parsercls in self._cw.vreg['components'].get('textparser', ()):
            parsercls(self._cw).parse(caller, text)


class TextParser(Component):
    """base class for text parser, responsible to extract some information
    from plain text. When something is done, it usually call the

      .fire_event(something, {event args})

    method on the caller.
    """
    __regid__ = 'textparser'
    __abstract__ = True

    def parse(self, caller, text):
        raise NotImplementedError


class ChangeStateTextParser(TextParser):
    """search some text for change state instruction in the form

         :<transition name>: #?<eid>
    """
    instr_rgx = re.compile(':(\w+):\s*#?(\d+)', re.U)

    def parse(self, caller, text):
        for trname, eid in self.instr_rgx.findall(text):
            try:
                entity = self._cw.entity_from_eid(int(eid))
            except UnknownEid:
                self.error("can't get entity with eid %s", eid)
                continue
            if not hasattr(entity, 'in_state'):
                self.error('bad change state instruction for eid %s', eid)
                continue
            iworkflowable = entity.cw_adapt_to('IWorkflowable')
            if iworkflowable.current_workflow:
                tr = iworkflowable.current_workflow.transition_by_name(trname)
            else:
                tr = None
            if tr and tr.may_be_fired(entity.eid):
                try:
                    trinfo = iworkflowable.fire_transition(tr)
                    caller.fire_event('state-changed', {'trinfo': trinfo,
                                                        'entity': entity})
                except Exception:
                    self.exception('while changing state of %s', entity)
            else:
                self.error("can't pass transition %s on entity %s",
                           trname, entity)