refactor form error handling:
* almost everything is in the base form class, with other form errors related code
* deprecate form_field_error in favor of field_error and format_error on the renderer
* fix pb with js localization of errors by properly using field.role_name()
* rename 'errors' into 'error' in forminfo to avoid confusion
"""abstract form classes for CubicWeb web client
:organization: Logilab
:copyright: 2001-2009 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 warnings import warn
from logilab.common.decorators import iclassmethod
from logilab.common.deprecation import deprecated
from cubicweb.appobject import AppObject
from cubicweb.view import NOINDEX, NOFOLLOW
from cubicweb import tags
from cubicweb.web import stdmsgs, httpcache, formfields
class FormViewMixIn(object):
"""abstract form view mix-in"""
category = 'form'
http_cache_manager = httpcache.NoHTTPCacheManager
add_to_breadcrumbs = False
def html_headers(self):
"""return a list of html headers (eg something to be inserted between
<head> and </head> of the returned page
by default forms are neither indexed nor followed
"""
return [NOINDEX, NOFOLLOW]
def linkable(self):
"""override since forms are usually linked by an action,
so we don't want them to be listed by appli.possible_views
"""
return False
###############################################################################
class metafieldsform(type):
"""metaclass for FieldsForm to retrieve fields defined as class attributes
and put them into a single ordered list: '_fields_'.
"""
def __new__(mcs, name, bases, classdict):
allfields = []
for base in bases:
if hasattr(base, '_fields_'):
allfields += base._fields_
clsfields = (item for item in classdict.items()
if isinstance(item[1], formfields.Field))
for fieldname, field in sorted(clsfields, key=lambda x: x[1].creation_rank):
if not field.name:
field.set_name(fieldname)
allfields.append(field)
classdict['_fields_'] = allfields
return super(metafieldsform, mcs).__new__(mcs, name, bases, classdict)
class FieldNotFound(Exception):
"""raised by field_by_name when a field with the given name has not been
found
"""
class Form(AppObject):
__metaclass__ = metafieldsform
__registry__ = 'forms'
parent_form = None
force_session_key = None
def __init__(self, req, rset, **kwargs):
super(Form, self).__init__(req, rset=rset, **kwargs)
self.restore_previous_post(self.session_key())
@property
def root_form(self):
"""return the root form"""
if self.parent_form is None:
return self
return self.parent_form.root_form
@property
def form_valerror(self):
"""the validation error exception if any"""
if self.parent_form is None:
return self._form_valerror
return self.parent_form.form_valerror
@property
def form_previous_values(self):
"""previously posted values (on validation error)"""
if self.parent_form is None:
return self._form_previous_values
return self.parent_form.form_previous_values
@iclassmethod
def _fieldsattr(cls_or_self):
if isinstance(cls_or_self, type):
fields = cls_or_self._fields_
else:
fields = cls_or_self.fields
return fields
@iclassmethod
def field_by_name(cls_or_self, name, role=None):
"""return field with the given name and role.
Raise FieldNotFound if the field can't be found.
"""
for field in cls_or_self._fieldsattr():
if field.name == name and field.role == role:
return field
raise FieldNotFound(name)
@iclassmethod
def fields_by_name(cls_or_self, name, role=None):
"""return a list of fields with the given name and role"""
return [field for field in cls_or_self._fieldsattr()
if field.name == name and field.role == role]
@iclassmethod
def remove_field(cls_or_self, field):
"""remove a field from form class or instance"""
cls_or_self._fieldsattr().remove(field)
@iclassmethod
def append_field(cls_or_self, field):
"""append a field to form class or instance"""
cls_or_self._fieldsattr().append(field)
@iclassmethod
def insert_field_before(cls_or_self, new_field, name, role='subject'):
field = cls_or_self.field_by_name(name, role)
fields = cls_or_self._fieldsattr()
fields.insert(fields.index(field), new_field)
@iclassmethod
def insert_field_after(cls_or_self, new_field, name, role='subject'):
field = cls_or_self.field_by_name(name, role)
fields = cls_or_self._fieldsattr()
fields.insert(fields.index(field)+1, new_field)
def session_key(self):
"""return the key that may be used to store / retreive data about a
previous post which failed because of a validation error
"""
if self.force_session_key is None:
return '%s#%s' % (self._cw.url(), self.domid)
return self.force_session_key
def restore_previous_post(self, sessionkey):
# get validation session data which may have been previously set.
# deleting validation errors here breaks form reloading (errors are
# no more available), they have to be deleted by application's publish
# method on successful commit
forminfo = self._cw.get_session_data(sessionkey, pop=True)
if forminfo:
self._form_previous_values = forminfo['values']
self._form_valerror = forminfo['error']
# if some validation error occured on entity creation, we have to
# get the original variable name from its attributed eid
foreid = self.form_valerror.entity
for var, eid in forminfo['eidmap'].items():
if foreid == eid:
self.form_valerror.eid = var
break
else:
self.form_valerror.eid = foreid
else:
self._form_previous_values = {}
self._form_valerror = None
def field_error(self, field):
"""return field's error if specified in current validation exception"""
if self.form_valerror:
if field.eidparam and self.edited_entity.eid != self.form_valerror.eid:
return None
try:
return self.form_valerror.errors.pop(field.role_name())
except KeyError:
if field.role and field.name in self.form_valerror:
warn('%s: errors key of attribute/relation should be suffixed by "-<role>"'
% self.form_valerror.__class__, DeprecationWarning)
return self.form_valerror.errors.pop(field.name)
return None
def remaining_errors(self):
return sorted(self.form_valerror.errors.items())
@deprecated('[3.6] use form.field_error and/or new renderer.render_error method')
def form_field_error(self, field):
"""return validation error for widget's field, if any"""
err = self.field_error(field)
if err:
return u'<span class="error">%s</span>' % err
return u''