web/views/csvexport.py
author Julien Jehannet <julien.jehannet@logilab.fr>
Fri, 05 Feb 2010 17:13:53 +0100
changeset 4527 67ab70e98488
parent 4252 6c4f109c2b03
child 5421 8167de96c523
permissions -rw-r--r--
[R] devtools: improve default data import mechanism Validation chain is now possible with checkers Before that the expected values needed to be coherent. Now, we can use ObjectStore to validate the input data * add new input transformers: - uppercase - lowercase * add new input checkers (raise AssertionError on error): - decimal: take care of possible comma character as number separator - integer: cast to int() - yesno: to validate boolean value - isalpha - required: input value *must* not be empty * new control checker: - optional: block possible exception we delete field in the returned dict instead of raising AssertionError (exclusive with required) Helper methods to manipulate indexes: * build_rqlindex() is used to build index based on already created entities * fetch() replace get_one()/get_many() methods by factorizing code Minor changes in reporting: * use tell() for all printing * let new value for askerrors to display automatically the report (used in crontab)

"""csv export views

:organization: Logilab
:copyright: 2001-2010 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.
:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses
"""
__docformat__ = "restructuredtext en"

from cubicweb.schema import display_name
from cubicweb.uilib import UnicodeCSVWriter
from cubicweb.view import EntityView, AnyRsetView

class CSVMixIn(object):
    """mixin class for CSV views"""
    templatable = False
    content_type = "text/comma-separated-values"
    binary = True # avoid unicode assertion
    csv_params = {'dialect': 'excel',
                  'quotechar': '"',
                  'delimiter': ';',
                  'lineterminator': '\n'}

    def set_request_content_type(self):
        """overriden to set a .csv filename"""
        self._cw.set_content_type(self.content_type, filename='cubicwebexport.csv')

    def csvwriter(self, **kwargs):
        params = self.csv_params.copy()
        params.update(kwargs)
        return UnicodeCSVWriter(self.w, self._cw.encoding, **params)


class CSVRsetView(CSVMixIn, AnyRsetView):
    """dumps raw result set in CSV"""
    __regid__ = 'csvexport'
    title = _('csv export')

    def call(self):
        writer = self.csvwriter()
        writer.writerow(self.columns_labels())
        rset, descr = self.cw_rset, self.cw_rset.description
        eschema = self._cw.vreg.schema.eschema
        for rowindex, row in enumerate(rset):
            csvrow = []
            for colindex, val in enumerate(row):
                etype = descr[rowindex][colindex]
                if val is not None and not eschema(etype).final:
                    # csvrow.append(val) # val is eid in that case
                    content = self._cw.view('textincontext', rset,
                                            row=rowindex, col=colindex)
                else:
                    content = self._cw.view('final', rset,
                                            format='text/plain',
                                            row=rowindex, col=colindex)
                csvrow.append(content)
            writer.writerow(csvrow)


class CSVEntityView(CSVMixIn, EntityView):
    """dumps rset's entities (with full set of attributes) in CSV

    the generated CSV file will have a table per entity type found in the
    resultset. ('table' here only means empty lines separation between table
    contents)
    """
    __regid__ = 'ecsvexport'
    title = _('csv entities export')

    def call(self):
        req = self._cw
        rows_by_type = {}
        writer = self.csvwriter()
        rowdef_by_type = {}
        for index in xrange(len(self.cw_rset)):
            entity = self.cw_rset.complete_entity(index)
            if entity.e_schema not in rows_by_type:
                rowdef_by_type[entity.e_schema] = [rs for rs, at in entity.e_schema.attribute_definitions()
                                                   if at != 'Bytes']
                rows_by_type[entity.e_schema] = [[display_name(req, rschema.type)
                                                  for rschema in rowdef_by_type[entity.e_schema]]]
            rows = rows_by_type[entity.e_schema]
            rows.append([entity.printable_value(rs.type, format='text/plain')
                         for rs in rowdef_by_type[entity.e_schema]])
        for rows in rows_by_type.itervalues():
            writer.writerows(rows)
            # use two empty lines as separator
            writer.writerows([[], []])