如何在Django CBV上序列化上下文？

Question

我在序列化第三方包(django-organizations)时遇到了问题，因为我希望在JSON中接收上下文。

类本身如下所示：

class OrganizationUserMixin(OrganizationMixin, JSONResponseMixin):
    """Mixin used like a SingleObjectMixin to fetch an organization user"""

    user_model = OrganizationUser
    org_user_context_name = 'organization_user'

    def get_user_model(self):
        return self.user_model

    def get_context_data(self, **kwargs):
        kwargs = super(OrganizationUserMixin, self).get_context_data(**kwargs)
        kwargs.update({self.org_user_context_name: self.object,
            self.org_context_name: self.object.organization})
        return kwargs

    def get_object(self):
        """ Returns the OrganizationUser object based on the primary keys for both
        the organization and the organization user.
        """
        if hasattr(self, 'organization_user'):
            return self.organization_user
        organization_pk = self.kwargs.get('organization_pk', None)
        user_pk = self.kwargs.get('user_pk', None)
        self.organization_user = get_object_or_404(
                self.get_user_model().objects.select_related(),
                user__pk=user_pk, organization__pk=organization_pk)
        return self.organization_user

我正在尝试将这个自定义JSONResponseMixin传递给我的OrganizationUserMixin类：

class JSONResponseMixin:
    """
    A mixin that can be used to render a JSON response.
    """
    def render_to_json_response(self, context, **response_kwargs):
        """
        Returns a JSON response, transforming 'context' to make the payload.
        """
        return JsonResponse(
            self.get_data(context),
            **response_kwargs
        )

    def get_data(self, context):
        print(context)
        return context

然后将render_to_response以OrganizationUserMixin形式重写如下：

def render_to_response(self, context, **response_kwargs):
    return self.render_to_json_response(context, **response_kwargs)

如果我打印context

看上去像这样

# {
# 'object': <OrganizationUser: Erik (MyOrgName)>, 
# 'organizationuser': <OrganizationUser: Erik (MyOrgName)>, 
# 'organization': <Organization: MyOrgName>, 
# 'view': <organizations.views.OrganizationUserDetail object at 0x1091a3ac0>, 
# 'organization_user': <OrganizationUser: Erik (MyOrgName)>
# }

我得到的错误消息是TypeError: Object of type OrganizationUser is not JSON serializable

如何在我的context中序列化JSONResponseMixin？

Answer 1

这里有两个选项，要么使用Django rest框架 (DRF)，要么实现对模型执行序列化的函数。

选项1

DRF是一种更可持续的解决方案，因为您可以扩展应用程序的API端，因为它将抽象大部分反序列化工作，并为您提供许多其他有用的功能，如路由器、ViewSets和其他功能。

示例代码

# serializers.py
from rest_framework import serializers

class OrganizationUserSerializer(serializers.ModelSerializer):
    class Meta:
        model = OrganizationUser
        fields = '__all__'


# views.py
from rest_framework import generics

class OrganizationUser(generics.RetrieveModelMixin):
    queryset = OrganizationUser.objects.all()
    serializer_class = OrganizationUserSerializer

选项2

尽管如此，如果您的JsonResponseMixin足够满足您的大部分需求，并且您的应用程序并不主要依赖于API，那么只需为您的模型添加序列化函数并在您的JsonResponseMixin.get_data()中调用它们即可。

示例代码：

# Models.py
class OrganizationUser(models.Model):
    ...

    def to_json(self):
        # assuming you have a field name and organization
        return {"name": self.name, "organization": self.organization.to_json()}

# mixins.py
class JSONResponseMixin:
    """
    A mixin that can be used to render a JSON response.
    """
    def render_to_json_response(self, context, **response_kwargs):
        """
        Returns a JSON response, transforming 'context' to make the payload.
        """
        return JsonResponse(
            self.get_data(context),
            **response_kwargs
        )

    def get_data(self, context):
        data = {}
        for key, val in context:
            if hasattr(val, "to_json"):
                data[key] = val.to_json()
            else:
                data[key] = val
        return data