1 """SPARQL integration

     2 

     3 :organization: Logilab

     4 :copyright: 2009 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.

     5 :contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr

     6 :license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses

     7 """

     8 import rql

     9 from yams import xy

    10 

    11 from cubicweb.view import StartupView

    12 from cubicweb.web import form, formfields, formwidgets as fwdgs

    13 from cubicweb.web.views import forms, urlrewrite

    14 from cubicweb.spa2rql import Sparql2rqlTranslator

    15 

    16 

    17 class SparqlForm(forms.FieldsForm):

    18     id = 'sparql'

    19     sparql = formfields.StringField(help=_('type here a sparql qyery'))

    20     vid = formfields.StringField(initial='sparql', widget=fwdgs.HiddenInput)

    21     form_buttons = [fwdgs.SubmitButton()]

    22     @property

    23     def action(self):

    24         return self.req.url()

    25 

    26 

    27 class SparqlFormView(form.FormViewMixIn, StartupView):

    28     id = 'sparql'

    29     def call(self):

    30         form = self.vreg.select('forms', 'sparql', self.req)

    31         self.w(form.form_render())

    32         sparql = self.req.form.get('sparql')

    33         if sparql:

    34             try:

    35                 qi = Sparql2rqlTranslator(self.schema).translate(sparql)

    36                 rset = self.req.execute(qi.finalize())

    37             except rql.TypeResolverException, ex:

    38                 self.w(self.req._('can not resolve entity types:') + u' ' + unicode('ex'))

    39             except UnsupportedQuery:

    40                 self.w(self.req._('we are not yet ready to handle this query'))

    41             except xy.UnsupportedVocabulary, ex:

    42                 self.w(self.req._('unknown vocabulary:') + u' ' + unicode('ex'))

    43             self.wview('table', rset, 'null')