From 992330055eeb5d787ddd7d62dfc9121a2256fd9b Mon Sep 17 00:00:00 2001 From: Tom Christie Date: Thu, 13 Nov 2014 21:11:13 +0000 Subject: [PATCH] Refactor many --- rest_framework/relations.py | 22 +++++++++++++++++----- rest_framework/serializers.py | 25 ++++++++++++++++++++----- 2 files changed, 37 insertions(+), 10 deletions(-) diff --git a/rest_framework/relations.py b/rest_framework/relations.py index 6dc02a11b..79c8057b6 100644 --- a/rest_framework/relations.py +++ b/rest_framework/relations.py @@ -10,9 +10,17 @@ from django.utils.translation import ugettext_lazy as _ class PKOnlyObject(object): + """ + This is a mock object, used for when we only need the pk of the object + instance, but still want to return an object with a .pk attribute, + in order to keep the same interface as a regular model instance. + """ def __init__(self, pk): self.pk = pk + +# We assume that 'validators' are intended for the child serializer, +# rather than the parent serializer. MANY_RELATION_KWARGS = ( 'read_only', 'write_only', 'required', 'default', 'initial', 'source', 'label', 'help_text', 'style', 'error_messages' @@ -36,13 +44,17 @@ class RelatedField(Field): # We override this method in order to automagically create # `ManyRelatedField` classes instead when `many=True` is set. if kwargs.pop('many', False): - list_kwargs = {'child_relation': cls(*args, **kwargs)} - for key in kwargs.keys(): - if key in MANY_RELATION_KWARGS: - list_kwargs[key] = kwargs[key] - return ManyRelatedField(**list_kwargs) + return cls.many_init(*args, **kwargs) return super(RelatedField, cls).__new__(cls, *args, **kwargs) + @classmethod + def many_init(cls, *args, **kwargs): + list_kwargs = {'child_relation': cls(*args, **kwargs)} + for key in kwargs.keys(): + if key in MANY_RELATION_KWARGS: + list_kwargs[key] = kwargs[key] + return ManyRelatedField(**list_kwargs) + def run_validation(self, data=empty): # We force empty strings to None values for relational fields. if data == '': diff --git a/rest_framework/serializers.py b/rest_framework/serializers.py index a4aeeeb79..70bba8ab2 100644 --- a/rest_framework/serializers.py +++ b/rest_framework/serializers.py @@ -46,6 +46,9 @@ import warnings from rest_framework.relations import * # NOQA from rest_framework.fields import * # NOQA + +# We assume that 'validators' are intended for the child serializer, +# rather than the parent serializer. LIST_SERIALIZER_KWARGS = ( 'read_only', 'write_only', 'required', 'default', 'initial', 'source', 'label', 'help_text', 'style', 'error_messages', @@ -73,13 +76,25 @@ class BaseSerializer(Field): # We override this method in order to automagically create # `ListSerializer` classes instead when `many=True` is set. if kwargs.pop('many', False): - list_kwargs = {'child': cls(*args, **kwargs)} - for key in kwargs.keys(): - if key in LIST_SERIALIZER_KWARGS: - list_kwargs[key] = kwargs[key] - return ListSerializer(*args, **list_kwargs) + return cls.many_init(*args, **kwargs) return super(BaseSerializer, cls).__new__(cls, *args, **kwargs) + @classmethod + def many_init(cls, *args, **kwargs): + """ + This method implements the creation of a `ListSerializer` parent + class when `many=True` is used. You can customize it if you need to + control which keyword arguments are passed to the parent, and + which are passed to the child. + """ + child_serializer = cls(*args, **kwargs) + list_kwargs = {'child': child_serializer} + list_kwargs.update(dict([ + (key, value) for key, value in kwargs.items() + if key in LIST_SERIALIZER_KWARGS + ])) + return ListSerializer(*args, **list_kwargs) + def to_internal_value(self, data): raise NotImplementedError('`to_internal_value()` must be implemented.')