详解从Django Rest Framework响应中删除空字段

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)

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

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

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

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

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