Django REST framework视图的用法

from django.db import models

class Publisher(models.Model):
  name = models.CharField(max_length=16)

  def __str__(self):
    return self.name


class Author(models.Model):
  name = models.CharField(max_length=16)

  def __str__(self):
    return self.name


class Book(models.Model):
  title = models.CharField(max_length=32)
  CHOICES = ((1, 'Python'), (2, 'Go'), (3, 'Linux'))
  category = models.IntegerField(choices=CHOICES)
  pub_date = models.DateField()
  publisher = models.ForeignKey(to='Publisher', on_delete=models.CASCADE)
  authors = models.ManyToManyField(to='Author')

  def __str__(self):
    return self.title

from django.contrib import admin
from django.urls import path, re_path
from bms import views

urlpatterns = [
  path('admin/', admin.site.urls),
  # 查所有对象，与添加对象
  re_path(r'publishers/$', views.PublisherView.as_view()),
  # 带pk查询具体某一条数据
  re_path(r'publishers/(?P<pk>\d+)/$', views.PublisherDetailView.as_view()), # 出版社详情
]

from bms import models
from rest_framework import serializers


class PublisherModelSerializer(serializers.ModelSerializer):
  class Meta:
    model = models.Publisher
    fields = "__all__"


class AuthorModelSerializer(serializers.ModelSerializer):
  class Meta:
    model = models.Author
    fields = "__all__"

from bms import models
from rest_framework.views import APIView
from rest_framework.response import Response
from bms.serializers import PublisherModelSerializer


##################### 面向对象，手动实现REST framework视图功能##################
class GenericView(APIView):
  '''公用类'''
  queryset = None
  serializer_class = None

  def get_queryset(self):
    # 让每一次请求来的时候都现查一次数据
    print('GeneriView------',self)
    return self.queryset.all()

  def get_object(self, request, pk):
    # 获取具体queryset
    return self.get_queryset().filter(pk=pk)

class ListMixin(object):
  # mixi.n 混合类，不能单独使用，利用python支持多继承
  def get(self, request):
    print('ListMixin------------', self)
    queryset = self.get_queryset()
    ser_obj = self.serializer_class(queryset, many=True)
    return Response(ser_obj.data)


class CreateMixin(object):
  def post(self, request):
    ser_obj = self.serializer_class(data=request.data)
    if ser_obj.is_valid():
      ser_obj.save()
      return Response("ok")
    else:
      return Response(ser_obj.errors)


class RetrieveMixin(object):
  """ 获取具体某一条记录"""
  def retrieve(self, request, pk):
    '''将此get方法与ListMixin中的get方法区分'''
    obj = self.get_object(request, pk).first()
    if obj:
      ser_obj = self.serializer_class(obj)
      return Response(ser_obj.data)
    else:
      return Response("无效的id")


class UpdateMixin(object):
  def put(self, request, pk):
    obj = self.get_object(request, pk).first()
    if obj:
      ser_obj = self.serializer_class(instance=obj, data=request.data, partial=True)
      if ser_obj.is_valid():
        ser_obj.save()
        return Response(ser_obj.data)
      else:
        return Response(ser_obj.errors)
    else:
      return Response("无效的id")


class DestroyMixin(object):
  def delete(self, request, pk):
    obj = self.get_object(request, pk)
    if obj:
      obj.delete()
      return Response("删除成功")
    else:
      return Response("无效的id")


class RetrieveView(GenericView, RetrieveMixin):
  '''因两个get方法相冲图，在此曲线访问查询具体对象的get方法'''
  def get(self, request, pk):
    return self.retrieve(request, pk)


# 出版社
class PublisherView(GenericView, ListMixin, CreateMixin):
  '''查所有出版社，增加出版社'''
  # 只用写配置项
  queryset = models.Publisher.objects.all()
  serializer_class = PublisherModelSerializer


class PublisherDetailView(RetrieveView, UpdateMixin, DestroyMixin):
  '''查询具体某一出版社，编辑，删除'''
  queryset = models.Publisher.objects.all()
  serializer_class = PublisherModelSerializer

# 作者
class AuthorListView(ListCreateAPIView):
  queryset = models.Author.objects.all()
  serializer_class = AuthorModelSerializer


class AuthorDetailView(RetrieveUpdateDestroyAPIView):
  queryset = models.Author.objects.all()
  serializer_class = AuthorModelSerializer

from rest_framework.viewsets import ModelViewSet
class AuthorViewSet(ModelViewSet):
  """
    内部封装了这五个方法
    list()
    create()
    retrieve()
    update()
    destroy()

  """
  queryset = models.Author.objects.all()
  serializer_class = AuthorModelSerializer

urlpatterns = [
  path('admin/', admin.site.urls),
  # 查所有对象，与添加对象
  re_path(r'publishers/$', views.PublisherView.as_view()),
  # 带pk查询具体某一条数据
  re_path(r'publishers/(?P<pk>\d+)/$', views.PublisherDetailView.as_view()), # 出版社详情

  re_path(r'authors/$', views.AuthorViewSet.as_view(actions={'get': 'list', 'post': 'create'})), # 作者列表
  re_path(r'authors/(?P<pk>\d+)/$', views.AuthorViewSet.as_view(
    actions={'get': 'retrieve', 'put': 'update', 'delete': 'destroy'})
    ), # 作者详情
]

from rest_framework.routers import DefaultRouter

router = DefaultRouter()
router.register('authors', views.AuthorViewSet)

urlpatterns += router.urls