web/views/__init__.py
author Sylvain Thénault <sylvain.thenault@logilab.fr>
Thu, 10 Jun 2010 16:23:07 +0200
changeset 5715 2c3e83817a8e
parent 5424 8ecbcbff9777
child 6276 cb4a48b2250e
permissions -rw-r--r--
[view] add a new entity_call method to entity view protocol, allowing some to work with not yet created entities. Also, start considering 'eid' form parameters where we only consider 'rql', so we can move on bloquing arbitrary rql inputs (more to do on this...)

# copyright 2003-2010 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/>.
"""Views, forms, actions... for the CubicWeb web client

"""
__docformat__ = "restructuredtext en"

import os
import sys
import tempfile
from rql import nodes


def need_table_view(rset, schema):
    """return True if we think that a table view is more appropriate than a
    list or primary view to display the given result set
    """
    rqlst = rset.syntax_tree()
    if len(rqlst.children) > 1:
        # UNION query, use a table
        return True
    selected = rqlst.children[0].selection
    try:
        mainvar = selected[0]
    except AttributeError:
        # not a variable ref, using table view is probably a good option
        return True
    if not (isinstance(mainvar, nodes.VariableRef) or
            (isinstance(mainvar, nodes.Constant) and mainvar.uid)):
        return True
    for i, etype in enumerate(rset.description[0][1:]):
        # etype may be None on outer join
        if etype is None:
            return True
        # check the selected index node is a VariableRef (else we
        # won't detect aggregate function
        if not isinstance(selected[i+1], nodes.VariableRef):
            return True
        # if this is not a final entity
        if not schema.eschema(etype).final:
            return True
        # if this is a final entity not linked to the main variable
        var = selected[i+1].variable
        for vref in var.references():
            rel = vref.relation()
            if rel is None:
                continue
            if mainvar.is_equivalent(rel.children[0]):
                break
        else:
            return True
    return False

# FIXME: VID_BY_MIMETYPE is unfortunately a bit too naive since
#        some browsers (e.g. FF2) send a bunch of mimetypes in
#        the Accept header, for instance:
#          text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,
#          text/plain;q=0.8,image/png,*/*;q=0.5
VID_BY_MIMETYPE = {
    #'text/xml': 'xml',
    # XXX rss, owl...
}
def vid_from_rset(req, rset, schema):
    """given a result set, return a view id"""
    if rset is None:
        return 'index'
    for mimetype in req.parse_accept_header('Accept'):
        if mimetype in VID_BY_MIMETYPE:
            return VID_BY_MIMETYPE[mimetype]
    nb_rows = len(rset)
    # empty resultset
    if nb_rows == 0 :
        return 'noresult'
    # entity result set
    if not schema.eschema(rset.description[0][0]).final:
        if need_table_view(rset, schema):
            return 'table'
        if nb_rows == 1:
            if req.search_state[0] == 'normal':
                return 'primary'
            return 'outofcontext-search'
        if len(rset.column_types(0)) == 1:
            return 'sameetypelist'
        return 'list'
    return 'table'


def linksearch_select_url(req, rset):
    """when searching an entity to create a relation, return an url to select
    entities in the given rset
    """
    req.add_js( ('cubicweb.ajax.js', 'cubicweb.edition.js') )
    target, eid, r_type, searchedtype = req.search_state[1]
    if target == 'subject':
        id_fmt = '%s:%s:%%s' % (eid, r_type)
    else:
        id_fmt = '%%s:%s:%s' % (r_type, eid)
    triplets = '-'.join(id_fmt % row[0] for row in rset.rows)
    return "javascript: selectForAssociation('%s', '%s');" % (triplets, eid)


class TmpFileViewMixin(object):
    binary = True
    content_type = 'application/octet-stream'
    cache_max_age = 60*60*2 # stay in http cache for 2 hours by default

    def call(self):
        self.cell_call()

    def cell_call(self, row=0, col=0):
        self.cw_row, self.cw_col = row, col # in case one needs it
        fd, tmpfile = tempfile.mkstemp('.png')
        os.close(fd)
        self._generate(tmpfile)
        self.w(open(tmpfile, 'rb').read())
        os.unlink(tmpfile)