1， 安装： pip install djangorestframework
2，配置：settings > INSTALL_APP=['rest_framework']
3，创建App： python manage.py startapp App
4，配置 : settings > INSTALL_APP=['App'] (以上是基本配置,后面的Demo都需要)
5,models

class Book(models.Model):
    b_name = models.CharField(max_length=32)
    b_price = models.FloatField(default=1)

6,serializers

class BookSerializer(serializers.ModelSerializer):
    class Meta:
        model = Book
        fields = ['id', 'b_name', 'b_price']

7, urls:

# 主路由
urlpatterns = [
  path('app/', include('App.urls')),
]

# App urls
urlpatterns = [
    path('book/<int:id>/', views.BookView.as_view()), # 获取单个书籍信息
    path('books/', views.BooksView.as_view()), # 书籍复数操作
]

8, views : 此处用的是django的views,后面会继续针对views详细讲

# 获取书籍信息
class BookView(View):
    def get(self, request, id):
        book = Book.objects.get(pk=id)
# 将对象序列化为字典
        serializer = BookSerializer(book)
        book_dict = serializer.data
# 返回给前端
        data = {
            'msg': 'ok',
            'status': 200,
            'data': book_dict
        }
        return JsonResponse(data)

# 获取所有书籍信息
class BooksView(View):
    def get(self, request):
        books = Book.objects.all()
# 序列化复数的时候需要加many=True
        serializer = BookSerializer(books, many=True)
        books_dict = serializer.data
        data = {
            'msg': 'ok',
            'status': 200,
            'data': books_dict
        }
        return JsonResponse(data)

# 添加新的书籍
    def post(self, request):
        b_name = request.POST.get('b_name')
        b_price = request.POST.get('b_price')

# 以下逻辑不可取,没有验证的过程
        # book = Book()
        # book.b_name = b_name
        # book.b_price = b_price
        #
        # book.save()
        #
        # serializer = BookSerializer(book)
        # book_dict = serializer.data
        #
        # data = {
        #     'msg': 'create ok',
        #     'status': 210,
        #     'data': book_dict
        # }
        #
        # return JsonResponse(data)
# 正确的方式
        book_data = {
            "b_name": b_name,
            "b_price": b_price
        }
# 反序列化
        serializer = BookSerializer(data=book_data)
# 验证序列化是否有效is_valid()
        if not serializer.is_valid():
            data = {
                "msg": "fail",
                "status": status.HTTP_400_BAD_REQUEST,
                "error": serializer.errors
            }
# 无效返回错误
            return JsonResponse(data)
# 有效保存
        serializer.save()
        book_dict = serializer.data

        data = {
            "msg": "create ok",
            "status": 201,
            "data": book_dict
        }
# 返回信息
        return JsonResponse(data)

#