用djang rest framework写一个增删改查案例

这里是一个使用Django Rest Framework实现的增删改查案例。

首先，创建一个Django项目并安装Django Rest Framework：

pip install djangorestframework

接下来，创建一个模型类：

# models.py
from django.db import models

class Book(models.Model):
    title = models.CharField(max_length=100)
    author = models.CharField(max_length=100)
    description = models.TextField()

    def __str__(self):
        return self.title

创建完成后，需要在`settings.py`中配置`INSTALLED_APPS`和`REST_FRAMEWORK`：

# settings.py
INSTALLED_APPS = [
    ...
    'rest_framework',
    'books',
]

REST_FRAMEWORK = {
    'DEFAULT_PERMISSION_CLASSES': [
        'rest_framework.permissions.AllowAny',
    ]
}

接下来，创建一个序列化器来将模型转化为JSON格式：

# serializers.py
from rest_framework import serializers
from .models import Book

class BookSerializer(serializers.ModelSerializer):
    class Meta:
        model = Book
        fields = '__all__'

在视图中，我们需要继承`APIView`类来处理HTTP请求：

# views.py
from rest_framework.views import APIView
from rest_framework.response import Response
from rest_framework import status
from .models import Book
from .serializers import BookSerializer

class BookList(APIView):
    def get(self, request):
        books = Book.objects.all()
        serializer = BookSerializer(books, many=True)
        return Response(serializer.data)

    def post(self, request):
        serializer = BookSerializer(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 BookDetail(APIView):
    def get_object(self, pk):
        try:
            return Book.objects.get(pk=pk)
        except Book.DoesNotExist:
            raise Http404

    def get(self, request, pk):
        book = self.get_object(pk)
        serializer = BookSerializer(book)
        return Response(serializer.data)

    def put(self, request, pk):
        book = self.get_object(pk)
        serializer = BookSerializer(book, 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):
        book = self.get_object(pk)
        book.delete()
        return Response(status=status.HTTP_204_NO_CONTENT)

最后，需要在`urls.py`中定义路由：

# urls.py
from django.urls import path
from .views import BookList, BookDetail

urlpatterns = [
    path('books/', BookList.as_view(), name='book-list'),
    path('books/<int:pk>/', BookDetail.as_view(), name='book-detail'),
]

现在，我们就可以使用这个API来进行增删改查操作了。例如，使用HTTP POST请求创建一本新书：

POST /books/
{
    "title": "Python for Data Science",
    "author": "John Smith",
    "description": "A comprehensive guide to data science using Python"
}

使用HTTP GET请求获取所有书籍：

GET /books/

使用HTTP GET请求获取一本书籍：

GET /books/1/

使用HTTP PUT请求更新一本书籍：

PUT /books/1/
{
    "title": "Python for Machine Learning",
    "author": "John Smith",
    "description": "A comprehensive guide to machine learning using Python"
}

使用HTTP DELETE请求删除一本书籍：

DELETE /books/1/