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超轻量级php框架startmvc

详解从Django Rest Framework响应中删除空字段

更新时间:2020-06-19 23:06:01 作者:startmvc
我使用django-rest-framework开发了一个API.我正在使用ModelSerializer返回模型的数据.models.pyclassMetaT

我使用django-rest-framework开发了一个API.

我正在使用ModelSerializer返回模型的数据.

models.py


class MetaTags(models.Model):
 title = models.CharField(_('Title'), max_length=255, blank=True, null=True)
 name = models.CharField(_('Name'), max_length=255, blank=True, null=True)

serializer.py


class MetaTagsSerializer(serializers.ModelSerializer):
 class Meta:
 model = MetaTags

响应


{
 "meta": {
 "title": null,
 "name": "XYZ"
 }
}

理想情况下,在API响应中,不应在响应中发送任何不存在的值.

当标题为null时,我希望响应为:


{
 "meta": {
 "name": "XYZ"
 }
}

您可以尝试覆盖to_native函数:


class MetaTagsSerializer(serializers.ModelSerializer):
 class Meta:
 model = MetaTags

 def to_native(self, obj):
 """
 Serialize objects -> primitives.
 """
 ret = self._dict_class()
 ret.fields = self._dict_class()

 for field_name, field in self.fields.items():
 if field.read_only and obj is None:
 continue
 field.initialize(parent=self, field_name=field_name)
 key = self.get_field_key(field_name)
 value = field.field_to_native(obj, field_name)

 # Continue if value is None so that it does not get serialized.
 if value is None:
 continue

 method = getattr(self, 'transform_%s' % field_name, None)
 if callable(method):
 value = method(obj, value)
 if not getattr(field, 'write_only', False):
 ret[key] = value
 ret.fields[key] = self.augment_field(field, field_name, key, value)

 return ret

我基本上从serializers.BaseSerializer复制了基本的to_native函数,并添加了一个值的检查.

更新:

至于DRF 3.0,to_native()被重命名为to_representation(),其实现稍有改变.这是DRF 3.0的代码,它忽略空值和空字符串值:


def to_representation(self, instance):
 """
 Object instance -> Dict of primitive datatypes.
 """
 ret = OrderedDict()
 fields = self._readable_fields

 for field in fields:
 try:
 attribute = field.get_attribute(instance)
 except SkipField:
 continue

 # KEY IS HERE:
 if attribute in [None, '']:
 continue

 # We skip `to_representation` for `None` values so that fields do
 # not have to explicitly deal with that case.
 #
 # For related fields with `use_pk_only_optimization` we need to
 # resolve the pk value.
 check_for_none = attribute.pk if isinstance(attribute, PKOnlyObject) else attribute
 if check_for_none is None:
 ret[field.field_name] = None
 else:
 ret[field.field_name] = field.to_representation(attribute)

 return ret

翻译自:https://stackoverflow.com/questions/27015931/remove-null-fields-from-django-rest-framework-response

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。

Django Rest Framework 删除空字段 Django Rest Framework 删除