django-rest-framework/rest_framework/utils/serializer_helpers.py
Petros Moisiadis 570187b959 Updated NestedBoundField to also handle empty string when rendering its form
If a NestedBoundField field has a value of `None` and is inside another NestedBoundField field, it will have its value converted to an empty string while the form of its enclosing field is being rendered. So, NestedBoundField fields with an empty string value must be handled the same way as NestedBoundField fields with a `None` value.
2015-11-26 17:07:57 +02:00

150 lines
4.5 KiB
Python

from __future__ import unicode_literals
import collections
from collections import OrderedDict
from django.utils.encoding import force_text
from rest_framework.compat import unicode_to_repr
class ReturnDict(OrderedDict):
"""
Return object from `serialier.data` for the `Serializer` class.
Includes a backlink to the serializer instance for renderers
to use if they need richer field information.
"""
def __init__(self, *args, **kwargs):
self.serializer = kwargs.pop('serializer')
super(ReturnDict, self).__init__(*args, **kwargs)
def copy(self):
return ReturnDict(self, serializer=self.serializer)
def __repr__(self):
return dict.__repr__(self)
def __reduce__(self):
# Pickling these objects will drop the .serializer backlink,
# but preserve the raw data.
return (dict, (dict(self),))
class ReturnList(list):
"""
Return object from `serialier.data` for the `SerializerList` class.
Includes a backlink to the serializer instance for renderers
to use if they need richer field information.
"""
def __init__(self, *args, **kwargs):
self.serializer = kwargs.pop('serializer')
super(ReturnList, self).__init__(*args, **kwargs)
def __repr__(self):
return list.__repr__(self)
def __reduce__(self):
# Pickling these objects will drop the .serializer backlink,
# but preserve the raw data.
return (list, (list(self),))
class BoundField(object):
"""
A field object that also includes `.value` and `.error` properties.
Returned when iterating over a serializer instance,
providing an API similar to Django forms and form fields.
"""
def __init__(self, field, value, errors, prefix=''):
self._field = field
self._prefix = prefix
self.value = value
self.errors = errors
self.name = prefix + self.field_name
def __getattr__(self, attr_name):
return getattr(self._field, attr_name)
@property
def _proxy_class(self):
return self._field.__class__
def __repr__(self):
return unicode_to_repr('<%s value=%s errors=%s>' % (
self.__class__.__name__, self.value, self.errors
))
def as_form_field(self):
value = '' if (self.value is None or self.value is False) else force_text(self.value)
return self.__class__(self._field, value, self.errors, self._prefix)
class NestedBoundField(BoundField):
"""
This `BoundField` additionally implements __iter__ and __getitem__
in order to support nested bound fields. This class is the type of
`BoundField` that is used for serializer fields.
"""
def __init__(self, field, value, errors, prefix=''):
if value is None or value is '':
value = {}
super(NestedBoundField, self).__init__(field, value, errors, prefix)
def __iter__(self):
for field in self.fields.values():
yield self[field.field_name]
def __getitem__(self, key):
field = self.fields[key]
value = self.value.get(key) if self.value else None
error = self.errors.get(key) if self.errors else None
if hasattr(field, 'fields'):
return NestedBoundField(field, value, error, prefix=self.name + '.')
return BoundField(field, value, error, prefix=self.name + '.')
def as_form_field(self):
values = {}
for key, value in self.value.items():
if isinstance(value, (list, dict)):
values[key] = value
else:
values[key] = '' if (value is None or value is False) else force_text(value)
return self.__class__(self._field, values, self.errors, self._prefix)
class BindingDict(collections.MutableMapping):
"""
This dict-like object is used to store fields on a serializer.
This ensures that whenever fields are added to the serializer we call
`field.bind()` so that the `field_name` and `parent` attributes
can be set correctly.
"""
def __init__(self, serializer):
self.serializer = serializer
self.fields = OrderedDict()
def __setitem__(self, key, field):
self.fields[key] = field
field.bind(field_name=key, parent=self.serializer)
def __getitem__(self, key):
return self.fields[key]
def __delitem__(self, key):
del self.fields[key]
def __iter__(self):
return iter(self.fields)
def __len__(self):
return len(self.fields)
def __repr__(self):
return dict.__repr__(self.fields)