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Diffstat (limited to 'webapp/django/forms/formsets.py')
| -rw-r--r-- | webapp/django/forms/formsets.py | 288 |
1 files changed, 288 insertions, 0 deletions
diff --git a/webapp/django/forms/formsets.py b/webapp/django/forms/formsets.py new file mode 100644 index 0000000000..2f13bf5fed --- /dev/null +++ b/webapp/django/forms/formsets.py @@ -0,0 +1,288 @@ +from forms import Form +from django.utils.encoding import StrAndUnicode +from django.utils.safestring import mark_safe +from fields import IntegerField, BooleanField +from widgets import Media, HiddenInput +from util import ErrorList, ValidationError + +__all__ = ('BaseFormSet', 'all_valid') + +# special field names +TOTAL_FORM_COUNT = 'TOTAL_FORMS' +INITIAL_FORM_COUNT = 'INITIAL_FORMS' +ORDERING_FIELD_NAME = 'ORDER' +DELETION_FIELD_NAME = 'DELETE' + +class ManagementForm(Form): + """ + ``ManagementForm`` is used to keep track of how many form instances + are displayed on the page. If adding new forms via javascript, you should + increment the count field of this form as well. + """ + def __init__(self, *args, **kwargs): + self.base_fields[TOTAL_FORM_COUNT] = IntegerField(widget=HiddenInput) + self.base_fields[INITIAL_FORM_COUNT] = IntegerField(widget=HiddenInput) + super(ManagementForm, self).__init__(*args, **kwargs) + +class BaseFormSet(StrAndUnicode): + """ + A collection of instances of the same Form class. + """ + def __init__(self, data=None, files=None, auto_id='id_%s', prefix=None, + initial=None, error_class=ErrorList): + self.is_bound = data is not None or files is not None + self.prefix = prefix or 'form' + self.auto_id = auto_id + self.data = data + self.files = files + self.initial = initial + self.error_class = error_class + self._errors = None + self._non_form_errors = None + # initialization is different depending on whether we recieved data, initial, or nothing + if data or files: + self.management_form = ManagementForm(data, auto_id=self.auto_id, prefix=self.prefix) + if self.management_form.is_valid(): + self._total_form_count = self.management_form.cleaned_data[TOTAL_FORM_COUNT] + self._initial_form_count = self.management_form.cleaned_data[INITIAL_FORM_COUNT] + else: + raise ValidationError('ManagementForm data is missing or has been tampered with') + else: + if initial: + self._initial_form_count = len(initial) + if self._initial_form_count > self.max_num and self.max_num > 0: + self._initial_form_count = self.max_num + self._total_form_count = self._initial_form_count + self.extra + else: + self._initial_form_count = 0 + self._total_form_count = self.extra + if self._total_form_count > self.max_num and self.max_num > 0: + self._total_form_count = self.max_num + initial = {TOTAL_FORM_COUNT: self._total_form_count, + INITIAL_FORM_COUNT: self._initial_form_count} + self.management_form = ManagementForm(initial=initial, auto_id=self.auto_id, prefix=self.prefix) + + # construct the forms in the formset + self._construct_forms() + + def __unicode__(self): + return self.as_table() + + def _construct_forms(self): + # instantiate all the forms and put them in self.forms + self.forms = [] + for i in xrange(self._total_form_count): + self.forms.append(self._construct_form(i)) + + def _construct_form(self, i, **kwargs): + """ + Instantiates and returns the i-th form instance in a formset. + """ + defaults = {'auto_id': self.auto_id, 'prefix': self.add_prefix(i)} + if self.data or self.files: + defaults['data'] = self.data + defaults['files'] = self.files + if self.initial: + try: + defaults['initial'] = self.initial[i] + except IndexError: + pass + # Allow extra forms to be empty. + if i >= self._initial_form_count: + defaults['empty_permitted'] = True + defaults.update(kwargs) + form = self.form(**defaults) + self.add_fields(form, i) + return form + + def _get_initial_forms(self): + """Return a list of all the intial forms in this formset.""" + return self.forms[:self._initial_form_count] + initial_forms = property(_get_initial_forms) + + def _get_extra_forms(self): + """Return a list of all the extra forms in this formset.""" + return self.forms[self._initial_form_count:] + extra_forms = property(_get_extra_forms) + + # Maybe this should just go away? + def _get_cleaned_data(self): + """ + Returns a list of form.cleaned_data dicts for every form in self.forms. + """ + if not self.is_valid(): + raise AttributeError("'%s' object has no attribute 'cleaned_data'" % self.__class__.__name__) + return [form.cleaned_data for form in self.forms] + cleaned_data = property(_get_cleaned_data) + + def _get_deleted_forms(self): + """ + Returns a list of forms that have been marked for deletion. Raises an + AttributeError is deletion is not allowed. + """ + if not self.is_valid() or not self.can_delete: + raise AttributeError("'%s' object has no attribute 'deleted_forms'" % self.__class__.__name__) + # construct _deleted_form_indexes which is just a list of form indexes + # that have had their deletion widget set to True + if not hasattr(self, '_deleted_form_indexes'): + self._deleted_form_indexes = [] + for i in range(0, self._total_form_count): + form = self.forms[i] + # if this is an extra form and hasn't changed, don't consider it + if i >= self._initial_form_count and not form.has_changed(): + continue + if form.cleaned_data[DELETION_FIELD_NAME]: + self._deleted_form_indexes.append(i) + return [self.forms[i] for i in self._deleted_form_indexes] + deleted_forms = property(_get_deleted_forms) + + def _get_ordered_forms(self): + """ + Returns a list of form in the order specified by the incoming data. + Raises an AttributeError is deletion is not allowed. + """ + if not self.is_valid() or not self.can_order: + raise AttributeError("'%s' object has no attribute 'ordered_forms'" % self.__class__.__name__) + # Construct _ordering, which is a list of (form_index, order_field_value) + # tuples. After constructing this list, we'll sort it by order_field_value + # so we have a way to get to the form indexes in the order specified + # by the form data. + if not hasattr(self, '_ordering'): + self._ordering = [] + for i in range(0, self._total_form_count): + form = self.forms[i] + # if this is an extra form and hasn't changed, don't consider it + if i >= self._initial_form_count and not form.has_changed(): + continue + # don't add data marked for deletion to self.ordered_data + if self.can_delete and form.cleaned_data[DELETION_FIELD_NAME]: + continue + # A sort function to order things numerically ascending, but + # None should be sorted below anything else. Allowing None as + # a comparison value makes it so we can leave ordering fields + # blamk. + def compare_ordering_values(x, y): + if x[1] is None: + return 1 + if y[1] is None: + return -1 + return x[1] - y[1] + self._ordering.append((i, form.cleaned_data[ORDERING_FIELD_NAME])) + # After we're done populating self._ordering, sort it. + self._ordering.sort(compare_ordering_values) + # Return a list of form.cleaned_data dicts in the order spcified by + # the form data. + return [self.forms[i[0]] for i in self._ordering] + ordered_forms = property(_get_ordered_forms) + + def non_form_errors(self): + """ + Returns an ErrorList of errors that aren't associated with a particular + form -- i.e., from formset.clean(). Returns an empty ErrorList if there + are none. + """ + if self._non_form_errors is not None: + return self._non_form_errors + return self.error_class() + + def _get_errors(self): + """ + Returns a list of form.errors for every form in self.forms. + """ + if self._errors is None: + self.full_clean() + return self._errors + errors = property(_get_errors) + + def is_valid(self): + """ + Returns True if form.errors is empty for every form in self.forms. + """ + if not self.is_bound: + return False + # We loop over every form.errors here rather than short circuiting on the + # first failure to make sure validation gets triggered for every form. + forms_valid = True + for errors in self.errors: + if bool(errors): + forms_valid = False + return forms_valid and not bool(self.non_form_errors()) + + def full_clean(self): + """ + Cleans all of self.data and populates self._errors. + """ + self._errors = [] + if not self.is_bound: # Stop further processing. + return + for i in range(0, self._total_form_count): + form = self.forms[i] + self._errors.append(form.errors) + # Give self.clean() a chance to do cross-form validation. + try: + self.clean() + except ValidationError, e: + self._non_form_errors = e.messages + + def clean(self): + """ + Hook for doing any extra formset-wide cleaning after Form.clean() has + been called on every form. Any ValidationError raised by this method + will not be associated with a particular form; it will be accesible + via formset.non_form_errors() + """ + pass + + def add_fields(self, form, index): + """A hook for adding extra fields on to each form instance.""" + if self.can_order: + # Only pre-fill the ordering field for initial forms. + if index < self._initial_form_count: + form.fields[ORDERING_FIELD_NAME] = IntegerField(label='Order', initial=index+1, required=False) + else: + form.fields[ORDERING_FIELD_NAME] = IntegerField(label='Order', required=False) + if self.can_delete: + form.fields[DELETION_FIELD_NAME] = BooleanField(label='Delete', required=False) + + def add_prefix(self, index): + return '%s-%s' % (self.prefix, index) + + def is_multipart(self): + """ + Returns True if the formset needs to be multipart-encrypted, i.e. it + has FileInput. Otherwise, False. + """ + return self.forms[0].is_multipart() + + def _get_media(self): + # All the forms on a FormSet are the same, so you only need to + # interrogate the first form for media. + if self.forms: + return self.forms[0].media + else: + return Media() + media = property(_get_media) + + def as_table(self): + "Returns this formset rendered as HTML <tr>s -- excluding the <table></table>." + # XXX: there is no semantic division between forms here, there + # probably should be. It might make sense to render each form as a + # table row with each field as a td. + forms = u' '.join([form.as_table() for form in self.forms]) + return mark_safe(u'\n'.join([unicode(self.management_form), forms])) + +def formset_factory(form, formset=BaseFormSet, extra=1, can_order=False, + can_delete=False, max_num=0): + """Return a FormSet for the given form class.""" + attrs = {'form': form, 'extra': extra, + 'can_order': can_order, 'can_delete': can_delete, + 'max_num': max_num} + return type(form.__name__ + 'FormSet', (formset,), attrs) + +def all_valid(formsets): + """Returns true if every formset in formsets is valid.""" + valid = True + for formset in formsets: + if not formset.is_valid(): + valid = False + return valid |