Django REST framework 学习纪要 Tutor

基于类的views

之前我们创建的views都是基于函数的，我们也可以基于类来写views

from snippets.models import Snippet
from snippets.serializers import SnippetSerializer
from django.http import Http404
from rest_framework.views import APIView
from rest_framework.response import Response
from rest_framework import status


class SnippetList(APIView):
    """
    list all snippets, or create a new snippet
    """
    def get(self, request, format=None):
        snippets = Snippet.objects.all()
        serializer = SnippetSerializer(snippets, many=True)
        return Response(serializer.data)

    def post(self, request, format=None):
        serializer = SnippetSerializer(data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data, status=status.HTTP_201_CREATED)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)


class SnippetDetail(APIView):
    """
    retrieve, update or delete a snippet instance
    """
    def get_object(self, pk):
        try:
            return Snippet.objects.get(pk=pk)
        except Snippet.DoesNotExist:
            raise Http404

    def get(self, request, pk, format=None):
        snippet = self.get_object(pk)
        serializer = SnippetSerializer(snippet)
        return Response(serializer.data)

    def put(self, request, pk, format=None):
        snippet = self.get_object(pk)
        serializer = SnippetSerializer(snippet, data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

    def delete(self, request, pk, format=None):
        snippet = self.get_object()
        snippet.delete()
        return Response(status=status.HTTP_204_NO_CONTENT)

接下来相应地去修改urls.py

from django.conf.urls import url
from rest_framework.urlpatterns import format_suffix_patterns
from snippets import views

urlpatterns = [
    url(r'^snippets/$', views.SnippetList.as_view()),
    url(r'^snippets/(?P<pk>[0-9]+)/$', views.SnippetDetail.as_view()),
]

urlpatterns = format_suffix_patterns(urlpatterns)

使用mixins

相比函数型views来说，基于类的views可以很容易地通过继承来去复用代码。
刚才我们创建的API中，基本都是数据库的增删改查操作，这种常见的操作都已经在REST框架中定义好了，在mixin类中，我们只需要去继承它。
再次重构views.py

from snippets.models import Snippet
from snippets.serializers import SnippetSerializer
from rest_framework import mixins
from rest_framework import generics


class SnippetList(mixins.ListModelMixin,
                  mixins.CreateModelMixin,
                  generics.GenericAPIView):
    queryset = Snippet.objects.all()
    serializer_class = SnippetSerializer

    def get(self, request, *args, **kwargs):
        return self.list(request, *args, **kwargs)

    def post(self, request, *args, **kwargs):
        return self.create(request, *args, **kwargs)

SnippetList这个类，首先继承于GenericAPIView，这个类提供了核心功能，接下来是继承于ListModelMixin和CreateModelMixin类，这两个类分别提供了.list()和.create()功能。

接下来重构下一个API

class SnippetDetail(mixins.RetrieveModelMixin,
                    mixins.UpdateModelMixin,
                    mixins.DestroyModelMixin,
                    generics.GenericAPIView):
    queryset = Snippet.objects.all()
    serializer_class = SnippetSerializer

    def get(self, request, *args, **kwargs):
        return self.retrieve(request, *args, **kwargs)

    def put(self, request, *args, **kwargs):
        return self.update(request, *args, **kwargs)

    def delete(self, request, *args, **kwargs):
        return self.destroy(request, *args, **kwargs)

RetrieveModelMixin, UpdateModelMixin, DestroyModelMixin分别提供了retrieve(), update(), destroy()功能

继承更通用的generic类

from snippets.models import Snippet
from snippets.serializers import SnippetSerializer
from rest_framework import generics


class SnippetList(generics.ListCreateAPIView):
    queryset = Snippet.objects.all()
    serializer_class = SnippetSerializer


class SnippetDetail(generics.RetrieveUpdateDestroyAPIView):
    queryset = Snippet.objects.all()
    serializer_class = SnippetSerializer

关于

本人是初学Django REST framework，Django REST framework 学习纪要系列文章是我从官网文档学习后的初步消化成果，如有错误，欢迎指正。

学习用代码Github仓库：shelmingsong/django_rest_framework

本文参考的官网文档：Tutorial 3: Class-based Views

博客更新地址

• 宋明耀的博客 [ 第一时间更新 ]
• 知乎专栏 Python Cookbook
• 简书 流月0的文章