+
−# copyright 2003-2012 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/>.
+
−"""json export views"""
+
−
+
−__docformat__ = "restructuredtext en"
+
−from cubicweb import _
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−
+
−from cubicweb.uilib import rest_traceback
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−
+
−from cubicweb.utils import json_dumps
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−from cubicweb.predicates import ExpectedValuePredicate, any_rset, empty_rset
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−from cubicweb.view import EntityView, AnyRsetView
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−from cubicweb.web.application import anonymized_request
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−from cubicweb.web.views import basecontrollers, management
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−
+
−class JsonpController(basecontrollers.ViewController):
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−    """The jsonp controller is the same as a ViewController but :
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−
+
−    - anonymize request (avoid CSRF attacks)
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−    - if ``vid`` parameter is passed, make sure it's sensible (i.e. either
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−      "jsonexport" or "ejsonexport")
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−    - if ``callback`` request parameter is passed, it's used as json padding
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−
+
−
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−    Response's content-type will either be ``application/javascript`` or
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−    ``application/json`` depending on ``callback`` parameter presence or not.
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−    """
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−    __regid__ = 'jsonp'
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−
+
−    def publish(self, rset=None):
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−        if 'vid' in self._cw.form:
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−            vid = self._cw.form['vid']
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−            if vid not in ('jsonexport', 'ejsonexport'):
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−                self.warning("vid %s can't be used with jsonp controller, "
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−                             "falling back to jsonexport", vid)
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−                self._cw.form['vid'] = 'jsonexport'
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−        else: # if no vid is specified, use jsonexport
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−            self._cw.form['vid'] = 'jsonexport'
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−        if self._cw.vreg.config['anonymize-jsonp-queries']:
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−            with anonymized_request(self._cw):
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−                return self._get_json_data(rset)
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−        else:
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−            return self._get_json_data(rset)
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−
+
−    def _get_json_data(self, rset):
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−        json_data = super(JsonpController, self).publish(rset)
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−        if 'callback' in self._cw.form: # jsonp
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−            json_padding = self._cw.form['callback'].encode('ascii')
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−            # use ``application/javascript`` if ``callback`` parameter is
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−            # provided, keep ``application/json`` otherwise
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−            self._cw.set_content_type('application/javascript')
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−            json_data = json_padding + b'(' + json_data + b')'
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−        return json_data
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−
+
−
+
−class JsonMixIn(object):
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−    """mixin class for json views
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−
+
−    Handles the following optional request parameters:
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−
+
−    - ``_indent`` : must be an integer. If found, it is used to pretty print
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−      json output
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−    """
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−    templatable = False
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−    content_type = 'application/json'
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−    binary = True
+
−
+
−    def wdata(self, data):
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−        if '_indent' in self._cw.form:
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−            indent = int(self._cw.form['_indent'])
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−        else:
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−            indent = None
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−        # python's json.dumps escapes non-ascii characters
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−        self.w(json_dumps(data, indent=indent).encode('ascii'))
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−
+
−
+
−class JsonRsetView(JsonMixIn, AnyRsetView):
+
−    """dumps raw result set in JSON format"""
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−    __regid__ = 'jsonexport'
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−    __select__ = any_rset() # means rset might be empty or have any shape
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−    title = _('json-export-view')
+
−
+
−    def call(self):
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−        # XXX mimic w3c recommandations to serialize SPARQL results in json?
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−        #     http://www.w3.org/TR/rdf-sparql-json-res/
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−        self.wdata(self.cw_rset.rows)
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−
+
−
+
−class JsonEntityView(JsonMixIn, EntityView):
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−    """dumps rset entities in JSON
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−
+
−    The following additional metadata is added to each row :
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−
+
−    - ``__cwetype__`` : entity type
+
−    """
+
−    __regid__ = 'ejsonexport'
+
−    __select__ = EntityView.__select__ | empty_rset()
+
−    title = _('json-entities-export-view')
+
−
+
−    def call(self):
+
−        entities = []
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−        for entity in self.cw_rset.entities():
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−            entity.complete() # fetch all attributes
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−            # hack to add extra metadata
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−            entity.cw_attr_cache.update({
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−                    '__cwetype__': entity.cw_etype,
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−                    })
+
−            entities.append(entity)
+
−        self.wdata(entities)
+
−
+
−
+
−class _requested_vid(ExpectedValuePredicate):
+
−    """predicate that checks vid parameter value
+
−
+
−    It differs from ``match_view`` in that it doesn't expect a ``view``
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−    parameter to be given to ``select`` but will rather check
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−    ``req.form['vid']`` to match expected vid.
+
−    """
+
−    def __call__(self, cls, req, rset=None, **kwargs):
+
−        return req.form.get('vid') in self.expected
+
−
+
−
+
−class JsonErrorView(JsonMixIn, management.ErrorView):
+
−    """custom error view selected when client asks for a json view
+
−
+
−    The returned json object will contain err / traceback informations.
+
−    """
+
−    __select__ = (management.ErrorView.__select__ &
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−                  _requested_vid('jsonexport', 'ejsonexport'))
+
−
+
−    def call(self):
+
−        errmsg, exclass, excinfo = self._excinfo()
+
−        self.wdata({
+
−            'errmsg': errmsg,
+
−            'exclass': exclass,
+
−            'traceback': rest_traceback(excinfo, errmsg),
+
−            })