import copy
from itertools import chain
from django import forms
from django.contrib.postgres.validators import (
ArrayMaxLengthValidator, ArrayMinLengthValidator,
)
from django.core.exceptions import ValidationError
from django.utils.translation import gettext_lazy as _
from ..utils import prefix_validation_error
[документация]class SimpleArrayField(forms.CharField):
default_error_messages = {
'item_invalid': _('Item %(nth)s in the array did not validate:'),
}
def __init__(self, base_field, *, delimiter=',', max_length=None, min_length=None, **kwargs):
self.base_field = base_field
self.delimiter = delimiter
super().__init__(**kwargs)
if min_length is not None:
self.min_length = min_length
self.validators.append(ArrayMinLengthValidator(int(min_length)))
if max_length is not None:
self.max_length = max_length
self.validators.append(ArrayMaxLengthValidator(int(max_length)))
def clean(self, value):
value = super().clean(value)
return [self.base_field.clean(val) for val in value]
def prepare_value(self, value):
if isinstance(value, list):
return self.delimiter.join(str(self.base_field.prepare_value(v)) for v in value)
return value
def to_python(self, value):
if isinstance(value, list):
items = value
elif value:
items = value.split(self.delimiter)
else:
items = []
errors = []
values = []
for index, item in enumerate(items):
try:
values.append(self.base_field.to_python(item))
except ValidationError as error:
errors.append(prefix_validation_error(
error,
prefix=self.error_messages['item_invalid'],
code='item_invalid',
params={'nth': index + 1},
))
if errors:
raise ValidationError(errors)
return values
def validate(self, value):
super().validate(value)
errors = []
for index, item in enumerate(value):
try:
self.base_field.validate(item)
except ValidationError as error:
errors.append(prefix_validation_error(
error,
prefix=self.error_messages['item_invalid'],
code='item_invalid',
params={'nth': index + 1},
))
if errors:
raise ValidationError(errors)
def run_validators(self, value):
super().run_validators(value)
errors = []
for index, item in enumerate(value):
try:
self.base_field.run_validators(item)
except ValidationError as error:
errors.append(prefix_validation_error(
error,
prefix=self.error_messages['item_invalid'],
code='item_invalid',
params={'nth': index + 1},
))
if errors:
raise ValidationError(errors)
def has_changed(self, initial, data):
try:
value = self.to_python(data)
except ValidationError:
pass
else:
if initial in self.empty_values and value in self.empty_values:
return False
return super().has_changed(initial, data)
class SplitArrayWidget(forms.Widget):
template_name = 'postgres/widgets/split_array.html'
def __init__(self, widget, size, **kwargs):
self.widget = widget() if isinstance(widget, type) else widget
self.size = size
super().__init__(**kwargs)
@property
def is_hidden(self):
return self.widget.is_hidden
def value_from_datadict(self, data, files, name):
return [self.widget.value_from_datadict(data, files, '%s_%s' % (name, index))
for index in range(self.size)]
def value_omitted_from_data(self, data, files, name):
return all(
self.widget.value_omitted_from_data(data, files, '%s_%s' % (name, index))
for index in range(self.size)
)
def id_for_label(self, id_):
# See the comment for RadioSelect.id_for_label()
if id_:
id_ += '_0'
return id_
def get_context(self, name, value, attrs=None):
attrs = {} if attrs is None else attrs
context = super().get_context(name, value, attrs)
if self.is_localized:
self.widget.is_localized = self.is_localized
value = value or []
context['widget']['subwidgets'] = []
final_attrs = self.build_attrs(attrs)
id_ = final_attrs.get('id')
for i in range(max(len(value), self.size)):
try:
widget_value = value[i]
except IndexError:
widget_value = None
if id_:
final_attrs = {**final_attrs, 'id': '%s_%s' % (id_, i)}
context['widget']['subwidgets'].append(
self.widget.get_context(name + '_%s' % i, widget_value, final_attrs)['widget']
)
return context
@property
def media(self):
return self.widget.media
def __deepcopy__(self, memo):
obj = super().__deepcopy__(memo)
obj.widget = copy.deepcopy(self.widget)
return obj
@property
def needs_multipart_form(self):
return self.widget.needs_multipart_form
[документация]class SplitArrayField(forms.Field):
default_error_messages = {
'item_invalid': _('Item %(nth)s in the array did not validate:'),
}
def __init__(self, base_field, size, *, remove_trailing_nulls=False, **kwargs):
self.base_field = base_field
self.size = size
self.remove_trailing_nulls = remove_trailing_nulls
widget = SplitArrayWidget(widget=base_field.widget, size=size)
kwargs.setdefault('widget', widget)
super().__init__(**kwargs)
def _remove_trailing_nulls(self, values):
index = None
if self.remove_trailing_nulls:
for i, value in reversed(list(enumerate(values))):
if value in self.base_field.empty_values:
index = i
else:
break
if index is not None:
values = values[:index]
return values, index
def to_python(self, value):
value = super().to_python(value)
return [self.base_field.to_python(item) for item in value]
def clean(self, value):
cleaned_data = []
errors = []
if not any(value) and self.required:
raise ValidationError(self.error_messages['required'])
max_size = max(self.size, len(value))
for index in range(max_size):
item = value[index]
try:
cleaned_data.append(self.base_field.clean(item))
except ValidationError as error:
errors.append(prefix_validation_error(
error,
self.error_messages['item_invalid'],
code='item_invalid',
params={'nth': index + 1},
))
cleaned_data.append(None)
else:
errors.append(None)
cleaned_data, null_index = self._remove_trailing_nulls(cleaned_data)
if null_index is not None:
errors = errors[:null_index]
errors = list(filter(None, errors))
if errors:
raise ValidationError(list(chain.from_iterable(errors)))
return cleaned_data
def has_changed(self, initial, data):
try:
data = self.to_python(data)
except ValidationError:
pass
else:
data, _ = self._remove_trailing_nulls(data)
if initial in self.empty_values and data in self.empty_values:
return False
return super().has_changed(initial, data)