如何在Django中使用通用类视图实现嵌套路由（非ViewSets）

需求说明 #

需要实现以下API端点：

• /products/
• /products/<product_pk>/
• /products/<product_pk>/reviews/
• /products/<product_pk>/reviews/<review_pk>/

原代码问题分析 #

原URL配置 #

# urls.py
from django.urls import path, include
from . import views

urlpatterns = [
    path("products/", views.ProductList.as_view()),
    path(
        "products/<int:product_pk>/",
        include(
            [
                path("", views.ProductDetail.as_view()),
                path("reviews/", views.ReviewList.as_view()),
                path("reviews/<int:review_pk>/", views.ReviewDetail.as_view()),
            ]
        ),
    )
]

原视图代码 #

# views.py
class ProductList(ListCreateAPIView):
    queryset = Product.objects.all()
    serializer = ProductSerializer


class ProductDetail(RetrieveUpdateDestroyAPIView):
    queryset = Product.objects.all()
    serializer = ProductSerializer
    lookup_field = "product_pk"


class ReviewList(ListCreateAPIView):
    serializer_class = ReviewSerializer

    def get_queryset(self):
        return Review.objects.filter(product_id=self.kwargs["product_pk"]).all()

    def get_serializer_context(self):
        return {"product_id": self.kwargs["product_pk"]}


class ReviewDetail(RetrieveUpdateDestroyAPIView):
    serializer_class = ReviewSerializer
    lookup_field = "review_pk"

    def get_queryset(self):
        return Review.objects.filter(product_id=self.kwargs["product_pk"]).all()

问题1解决：/products/1/reviews/1 报错 #

报错原因：ReviewDetail里的lookup_field被设置为review_pk，但Review模型中不存在这个字段。lookup_field的作用是指定模型中用于查询的字段名，URL里的参数名需要用lookup_url_kwarg来对应。

修改ReviewDetail视图：

class ReviewDetail(RetrieveUpdateDestroyAPIView):
    serializer_class = ReviewSerializer
    lookup_field = "id"  # 对应Review模型的主键字段
    lookup_url_kwarg = "review_pk"  # 对应URL中的参数名

    def get_queryset(self):
        return Review.objects.filter(product_id=self.kwargs["product_pk"]).all()

这样DRF会用URL中的review_pk值，匹配Review模型的id字段，解决字段找不到的错误。

问题2解决：/products/1 报错 #

报错原因：ProductDetail里的lookup_field设为product_pk，但Product模型中没有这个字段，同样混淆了lookup_field和lookup_url_kwarg的作用。

修改ProductDetail视图：

class ProductDetail(RetrieveUpdateDestroyAPIView):
    queryset = Product.objects.all()
    serializer_class = ProductSerializer
    lookup_field = "id"  # 对应Product模型的主键字段
    lookup_url_kwarg = "product_pk"  # 对应URL中的参数名

这里lookup_field指定用模型的id字段查询，lookup_url_kwarg告诉DRF从URL的product_pk参数中获取查询值，既满足URL参数命名需求，又不会和评论的查询字段冲突。

最终完整视图代码 #

# views.py
from rest_framework.generics import (
    ListCreateAPIView,
    RetrieveUpdateDestroyAPIView
)
from .models import Product, Review
from .serializers import ProductSerializer, ReviewSerializer


class ProductList(ListCreateAPIView):
    queryset = Product.objects.all()
    serializer_class = ProductSerializer  # 原代码写的serializer是错误的，需改为serializer_class


class ProductDetail(RetrieveUpdateDestroyAPIView):
    queryset = Product.objects.all()
    serializer_class = ProductSerializer
    lookup_field = "id"
    lookup_url_kwarg = "product_pk"


class ReviewList(ListCreateAPIView):
    serializer_class = ReviewSerializer

    def get_queryset(self):
        return Review.objects.filter(product_id=self.kwargs["product_pk"])

    def get_serializer_context(self):
        return {"product_id": self.kwargs["product_pk"]}


class ReviewDetail(RetrieveUpdateDestroyAPIView):
    serializer_class = ReviewSerializer
    lookup_field = "id"
    lookup_url_kwarg = "review_pk"

    def get_queryset(self):
        return Review.objects.filter(product_id=self.kwargs["product_pk"])

内容的提问来源于stack exchange，提问作者asa