在django rest框架中添加元数据到过滤

Question

我有一个通用的ListCreateAPIView观点.我已经实现了一个get_queryset执行搜索的功能.该函数解析查询,提取标签和术语并返回查询集.

def get_queryset(self):
        query = self.request.QUERY_PARAMS.get('query', None)

        # No deleted items
        queryset = Items.objects.filter(deleted__isnull=True)

        if query is None:
            return queryset

        predicates = []

        # Generate predicates from query       

        queryset = queryset.filter(reduce(__and__,predicates))
        return queryset

使用get_queryset函数中的数据向响应添加元数据的最佳方法是什么？

我正在寻找类似于分页方式的东西.

{
 query : {
     terms : ['term1','term2'], 
     tags  : ['tag1','tag2'] , 
    }
 results : [
      { name : 'item1', .... }
      { name : 'item2', .... }
   ]
}

编辑

所以我FilterBackend为过滤创建了一个自定义,现在我有一个请求和响应的实例.看看django休息的分页代码,我看到它将结果包装在序列化器中.分页是构建到视图类中的,因此如果检测到分页符,fw将调用序列化.查看搜索API并没有产生任何新的想法.

我的问题仍然是,从过滤器后端向响应添加元数据的最佳和最少侵入性方法是什么？

我能想到的一种方式(以及我不喜欢的方法)是将matadata重载到过滤器后端的请求中,并finalize_response在视图中覆盖- 毫无疑问是最糟糕的方法.

Answer 1

我不确定这是最好的方法,但我可能会覆盖get简单地拦截响应对象并修改response.data但是你想要的.简单的事情

from rest_framework import generics

class SomeModelList(generics.ListCreateAPIView):
    """
    API endpoint representing a list of some things.
    """

    model = SomeModel
    serializer_class = SomeModelSerializer

    def get(self, request, *args, **kwargs):
        response = super(SomeModelList, self).get(request, *args, **kwargs)

        # redefine response.data to include original query params
        response.data = {
            'query': dict(request.QUERY_PARAMS),
            'results': response.data
        }

        return response

如果您发现自己在多个列表视图中重复此操作,则可以使用Mixin将自己保持干燥并将其包含在列表API类中:

from rest_framework import generics
from rest_framework.mixins import ListModelMixin

class IncludeQueryListMixin(ListModelMixin):
    def list(self, request, *args, **kwargs):
        response = super(IncludeQueryListMixin, self).list(request, *args, **kwargs)

        # redefine response.data to include original query params
        response.data = {
            'query': dict(request.QUERY_PARAMS),
            'results': response.data
        }

        return response


class SomeModelList(IncludeQueryListMixin, generics.ListCreateAPIView):
    """
    API endpoint representing a list of some things.
    """

    model = SomeModel
    serializer_class = SomeModelSerializer