Django REST framework 1

Django REST framework

Django REST framework官方文档：点击中文文档：点击

安装djangorestframework：pip3 install djangorestframework （pip3 list 查看详情和版本信息）
注册rest_framework（settings.py）

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'app01',
    'rest_framework',
]

settings.py

DRF序列化

做前后端分离的项目,前后端交互一般都选择JSON数据格式，JSON是一个轻量级的数据交互格式。后端给前端数据的时候都要转成json格式，那就需要对从数据库拿到的数据进行序列化。

要用DRF的序列化，就要遵循人家框架的一些标准

声明序列化类(app01目录下新建serializers.py文件)
Django CBV继承类是View，现在DRF要用APIView
Django中返回的时候用HTTPResponse，JsonResponse，render ，DRF用Response
DRF反序列化
- 当前端给后端发post的请求的时候，前端给后端传过来的数据，要进行一些校验然后保存到数据库。
- 这些校验以及保存工作，DRF的Serializer也提供了一些方法了，
- 首先要写反序列化用的一些字段，有些字段要跟序列化区分开，
- Serializer提供了.is_valid()和.save()方法

一、Serializer

1、声明序列化类（app01中serializers.py）

from rest_framework import serializers
from .models import Book

class PublisherSerializer(serializers.Serializer):
    id = serializers.IntegerField()
    title = serializers.CharField(max_length=32)


class AuthorSerializer(serializers.Serializer):
    id = serializers.IntegerField()
    name = serializers.CharField(max_length=32)


book_obj = {
        "title": "Alex的使用教程",
        "w_category": 1,
        "pub_time": "2018-10-09",
        "publisher_id": 1,
        "author_list": [1, 2]
    }


data = {
    "title": "Alex的使用教程2"
}

#3.1 验证器 validators  定义函数写验证规则
def my_validate(value):
    if "敏感信息" in value.lower():
        raise serializers.ValidationError("不能含有敏感信息")
    else:
        return value


class BookSerializer(serializers.Serializer):
    id = serializers.IntegerField(required=False)  #required=False  不需要校验
    title = serializers.CharField(max_length=32, validators=[my_validate])  #3.2 验证器  validators用自定义的验证方法，比validate_title权重高
    CHOICES = ((1, "Python"), (2, "Go"), (3, "Linux"))
    category = serializers.ChoiceField(choices=CHOICES, source="get_category_display", read_only=True)  #choices
    w_category = serializers.ChoiceField(choices=CHOICES, write_only=True)
    pub_time = serializers.DateField()
    #外键关系的序列化
    publisher = PublisherSerializer(read_only=True)  #read_only=True只序列化的时候用
    publisher_id = serializers.IntegerField(write_only=True)  #ForeignKey   #write_only=True只反序列化的时候用
    #ManyToMany的序列化
    author = AuthorSerializer(many=True, read_only=True)   #ManyToManyField
    author_list = serializers.ListField(write_only=True)
    #新建
    def create(self, validated_data):
        book = Book.objects.create(title=validated_data["title"], category=validated_data["w_category"],
                                pub_time=validated_data["pub_time"], publisher_id=validated_data["publisher_id"])
        book.author.add(*validated_data["author_list"])
        return book
    #修改
    def update(self, instance, validated_data):
        instance.title = validated_data.get("title", instance.title)
        instance.category = validated_data.get("w_category", instance.w_category)
        instance.pub_time = validated_data.get("pub_time", instance.pub_time)
        instance.publisher_id = validated_data.get("publisher_id", instance.publisher_id)
        if validated_data.get("author_list"):
            instance.author.set(validated_data["author_list"])
        instance.save()
        return instance
    #验证
    #1、单个字段的验证
    def validate_title(self, value):
        if "python" not in value.lower():
            raise serializers.ValidationError("标题必须含有python")
        return value
    #2、多个字段的验证
    def validate(self, attrs):
        if attrs["w_category"] == 1 and attrs["publisher_id"] == 1:
            return attrs
        else:
            raise serializers.ValidationError("分类以及标题不符合要求")
    #3、验证器 validators

app01中serializers.py

2、用声明的序列化类去序列化(app01中views.py)

from .models import Book

from rest_framework.views import APIView
from rest_framework.viewsets import GenericViewSet
from rest_framework.response import Response
from .serializers import BookSerializer



class BookView(APIView):
    def get(self, request):
        # book_obj = Book.objects.first()
        # ret = BookSerializer(book_obj)
        book_list = Book.objects.all()
        ret = BookSerializer(book_list, many=True)  #多个ManyToManyField
        return Response(ret.data)


    def post(self, request):
        print(request.data)
        serializer = BookSerializer(data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        else:
            return Response(serializer.errors)

class BookEditView(APIView):
    def get(self, request, id):
        book_obj = Book.objects.filter(id=id).first()
        ret = BookSerializer(book_obj)
        return Response(ret.data)

    def put(self, request, id):
        book_obj = Book.objects.filter(id=id).first()
        serializer = BookSerializer(book_obj, data=request.data, partial=True) #partial=True允许部分进行更新
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        else:
            return Response(serializer.errors)

    def delete(self, request, id):
        book_obj = Book.objects.filter(id=id).first()
        book_obj.delete()
        return Response("")

app01中views.py

二、ModelSerializer

跟模型紧密相关的序列化器
根据模型自动生成一组字段
默认实现了.update()以及.create()方法

1、定义一个ModelSerializer序列化器（app01中serializers.py）

from rest_framework import serializers
from .models import Book

# 验证器 validators  定义函数写验证规则
def my_validate(value):
    if "敏感信息" in value.lower():
        raise serializers.ValidationError("不能含有敏感信息")
    else:
        return value


class BookSerializer(serializers.ModelSerializer):
    #category = serializers.CharField(source="get_category_display",read_only=True)   #自定制
    category_display = serializers.SerializerMethodField(read_only=True)  # SerializerMethodField
    publisher_info = serializers.SerializerMethodField(read_only=True)
    authors = serializers.SerializerMethodField(read_only=True)

    def get_category_display(self, obj):
        return obj.get_category_display()

    def get_authors(self, obj):
        # obj是当前序列化的book对象
        #外键关联的对象有很多字段是用不到的~都传给前端会有数据冗余~就需要去定制序列化外键对象的哪些字段~~
        authors_query_set = obj.author.all()
        return [{"id": author_obj.id, "name": author_obj.name} for author_obj in authors_query_set]

    def get_publisher_info(self, obj):
        # obj 是我们序列化的每个Book对象
        # 外键关联的对象有很多字段是用不到的~都传给前端会有数据冗余~就需要去定制序列化外键对象的哪些字段~~
        publisher_obj = obj.publisher
        return {"id": publisher_obj.id, "title": publisher_obj.title}

    class Meta:
        model = Book
        # fields = ["id", "title", "pub_time"]
        # exclude = ["user"]
        # 包含某些字段 排除某些字段
        fields = "__all__"
        # depth = 1  #depth 代表找嵌套关系的第1层
        #注意：当序列化类MATE中定义了depth时，这个序列化类中引用字段（外键）则自动变为只读
        #read_only_fields = ["id", "category_display", "publisher_info", "authors"]
        extra_kwargs = {"category": {"write_only": True}, "publisher": {"write_only": True},
                        "author": {"write_only": True},"title": {"validators": [my_validate,]}}

app01中serializers.py

from rest_framework import serializers
from api import models


class CourseModelSerializer(serializers.ModelSerializer):
    # price = serializers.SerializerMethodField()
    # learn_num = serializers.SerializerMethodField()
    learn_num = serializers.IntegerField(source='order_details.count')
    course_detail_id = serializers.IntegerField(source='coursedetail.id')

    # def get_price(self, obj):
    #     # 把所有课程永久有效的价格拿出来
    #     price_obj = obj.price_policy.all().filter(valid_period=999).first()
    #     return price_obj.price

    # def get_learn_num(self, obj):
    #     return obj.order_details.count()

    # 修改序列化结果的终极方法
    def to_representation(self, instance):
        # 调用父类的同名方法把序列化的结果拿到
        data = super().to_representation(instance)
        # 针对序列化的结果做一些自定制操作
        # 判断当前这个课程是否有永久有效的价格
        price_obj = instance.price_policy.all().filter(valid_period=999).first()
        if price_obj:
            # 有永久有效的价格
            data['has_price'] = True
            data['price'] = price_obj.price
        else:
            # 没有永久有效的价格策略
            data['has_price'] = False
        return data

    class Meta:
        model = models.Course
        fields = '__all__'


class CourseCategoryModelSerializer(serializers.ModelSerializer):

    class Meta:
        model = models.CourseCategory
        fields = '__all__'

to_representation

三、Serializer和ModelSerializer的区别

四、JsonResponse和Django序列化

#app01中models.py
from django.db import models
__all__ = ["Book", "Publisher", "Author"]


class Book(models.Model):
    title = models.CharField(max_length=32, verbose_name="图书名称")
    CHOICES = ((1, "Python"), (2, "Go"), (3, "Linux"))
    category = models.IntegerField(choices=CHOICES, verbose_name="图书的类别")
    pub_time = models.DateField(verbose_name="图书的出版日期")

    publisher = models.ForeignKey(to="Publisher", on_delete=None)
    author = models.ManyToManyField(to="Author")

    def __str__(self):
        return self.title

    class Meta:
        verbose_name_plural = "01-图书表"
        db_table = verbose_name_plural


class Publisher(models.Model):
    title = models.CharField(max_length=32, verbose_name="出版社的名称")

    def __str__(self):
        return self.title

    class Meta:
        verbose_name_plural = "02-出版社表"
        db_table = verbose_name_plural


class Author(models.Model):
    name = models.CharField(max_length=32, verbose_name="作者的姓名")

    def __str__(self):
        return self.name

    class Meta:
        verbose_name_plural = "03-作者表"
        db_table = verbose_name_plural

#DRFDemo中urls.py
from django.contrib import admin
from django.urls import path, include
urlpatterns = [
    path('admin/', admin.site.urls),
    path('books/', include("SerDemo.urls")),
]
#app01中urls.py
from django.urls import path, include
from .views import BookView, BookEditView
urlpatterns = [
    path('list', BookView.as_view()),
    path('retrieve/<int:id>', BookEditView.as_view()),
]

app01中models.py 和 app01中的urls.py

#app01/views.py
from django.views import View
from django.http import HttpResponse, JsonResponse
from django.core import serializers
from .models import Book, Publisher

class BookView(View):
    #第一版 用.values JsonResponse实现序列化
    def get(self, request):
        book_list = Book.objects.values("id", "title", "category", "pub_time", "publisher")
        book_list = list(book_list)
        # 如果需要取外键关联的字段信息 需要循环获取外键 再去数据库查然后拼接成想要的
        ret = []
        for book in book_list:
            publisher_id = book["publisher"]
            publisher_obj = Publisher.objects.filter(id=publisher_id).first()
            book["publisher"] = {
                "id": publisher_id,
                "title": publisher_obj.title
            }
            ret.append(book)
        # ret = json.dumps(book_list, ensure_ascii=False)
        # return HttpResponse(ret) #时间
        return JsonResponse(ret, safe=False, json_dumps_params={"ensure_ascii": False})

    #第二版 用django serializers实现序列化
    # 能够得到要的效果，但是结构有点复杂,而且choices不能显示对应的文本
    def get(self, request):
        book_list = Book.objects.all()
        ret = serializers.serialize("json", book_list, ensure_ascii=False)
        return HttpResponse(ret)

JsonResponse和Django序列化

DRF的视图

在Django REST Framework中内置的Request类扩展了Django中的Request类，实现了很多方便的功能--如请求数据解析和认证等。
比如，区别于Django中的request从request.GET中获取URL参数，从request.POST中取某些情况下的POST数据。
在APIView中封装的request，就实现了请求数据的解析：
对于GET请求的参数通过request.query_params来获取。
对于POST请求、PUT请求的数据通过request.data来获取。

一、源码查找

django中写CBV的时候继承的是View，rest_framework继承的是APIView
不管是View还是APIView最开始调用的都是as_view()方法。
APIView继承了View, 并且执行了View中的as_view()方法，最后用csrf_exempt()方法包裹view把view返回了，用csrf_exempt()方法包裹后去掉了csrf的认证。
在View中的as_view方法返回了view函数，而view函数执行了self.dispatch()方法,但是这里是APIView调用的，所以先从APIView找dispatch()方法。
APIView的dispatch()方法中给request重新赋值了
去initialize_request中看下把什么赋值给了request，并且赋值给了self.request, 也就是视图中用的request.xxx到底是什么
可以看到，这个方法返回的是Request这个类的实例对象,注意看下这个Request类中的第一个参数request，是走django的时候的原来的request
去Request这个类里看这个Request类把原来的request赋值给了self._request, 也就是说以后_request是老的request，新的request是这个Request类
request.query_params 存放的是get请求的参数 request.data 存放的是所有的数据，包括post请求的以及put，patch请求
相比原来的django的request，现在的request更加精简，清晰了
框架提供了一个路由传参的方法ViewSetMixin

#1.徒手垒代码阶段
class SchoolView(APIView):
    def get(self, request, *args, **kwargs):
        query_set = models.School.objects.all()
        ser_obj = app01_serializers.SchoolSerializer(query_set, many=True)
        return Response(ser_obj.data)


class SchoolDetail(APIView):
    def get(self, request, pk, *args, **kwargs):
        obj = models.School.objects.filter(pk=pk).first()
        ser_obj = app01_serializers.SchoolSerializer(obj)
        return Response(ser_obj.data)

#路由
url(r'school/$', views.SchoolView.as_view()),
url(r'school/(?P<pk>\d+)/$', views.SchoolDetail.as_view()),

#2.使用混合类阶段

class SchoolView(GenericAPIView, mixins.ListModelMixin):
    queryset = models.School.objects.all()
    serializer_class = app01_serializers.SchoolSerializer

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


class SchoolDetail(GenericAPIView, mixins.RetrieveModelMixin, mixins.CreateModelMixin):
    queryset = models.School.objects.all()
    serializer_class = app01_serializers.SchoolSerializer

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

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

#路由
url(r'school/$', views.SchoolView.as_view()),
url(r'school/(?P<pk>\d+)/$', views.SchoolDetail.as_view()),


# 3.使用通用类

class SchoolView(ListCreateAPIView):
    queryset = models.School.objects.all()
    serializer_class = app01_serializers.SchoolSerializer


class SchoolDetail(RetrieveUpdateDestroyAPIView):
    queryset = models.School.objects.all()
    serializer_class = app01_serializers.SchoolSerializer

#路由
url(r'school/$', views.SchoolView.as_view()),
url(r'school/(?P<pk>\d+)/$', views.SchoolDetail.as_view()),

#4.使用视图集

class SchoolView(ModelViewSet):
    queryset = models.School.objects.all()
    serializer_class = app01_serializers.SchoolSerializer

#路由：
url(r'school/$', views.SchoolView.as_view({
    "get": "list",
    "post": "create",
})),
url(r'school/(?P<pk>\d+)/$', views.SchoolView.as_view({
    'get': 'retrieve',
    'put': 'update',
    'patch': 'partial_update',
    'delete': 'destroy'
})),

#高级路由

from rest_framework.routers import DefaultRouter

router = DefaultRouter()
router.register(r'school', views.SchoolView)
urlpatterns += router.urls

视图和路由

二、ModelViewSet

from django.urls import path, include
from .views import BookView, BookEditView, BookModelViewSet
urlpatterns = [
    # path('list', BookView.as_view()),
    # path('retrieve/<int:id>', BookEditView.as_view()),
    path('list', BookModelViewSet.as_view({"get": "list", "post": "create"})),
    path('retrieve/<int:pk>', BookModelViewSet.as_view({"get": "retrieve", "put": "update", "delete": "destroy"})),
]

app01中urls.py

from .models import Book
from .serializers import BookSerializer

from rest_framework.viewsets import ModelViewSet
class BookModelViewSet(ModelViewSet):
    queryset = Book.objects.all()
    serializer_class = BookSerializer

#现在的视图就只要写两行就可以了
#注意：用框架封装的视图~url上的那个关键字参数要用pk系统默认的
##path('retrieve/<int:pk>', BookModelViewSet.as_view({"get": "retrieve", "put": "update", "delete": "destroy"}))  用pk

# from rest_framework import views
# from rest_framework import generics
# from rest_framework import mixins
# from rest_framework import viewsets

app01中views.py

from .models import Book

from rest_framework.views import APIView
from rest_framework.response import Response
from .serializers import BookSerializer

class GenericAPIView(APIView):
    query_set = None
    serializer_class = None

    def get_queryset(self):
        return self.query_set

    def get_serializer(self, *args, **kwargs):
        return self.serializer_class(*args, **kwargs)


class ListModelMixin(object):
    def list(self, request):
        queryset = self.get_queryset()
        ret = self.get_serializer(queryset, many=True)
        return Response(ret.data)


class CreateModelMixin(object):
    def create(self, request):
        serializer = self.get_serializer(data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        else:
            return Response(serializer.errors)


class RetrieveModelMixin(object):
    def retrieve(self, request, id):
        book_obj = self.get_queryset().filter(id=id).first()
        ret = self.get_serializer(book_obj)
        return Response(ret.data)


class UpdateModelMixin(object):
    def update(self, request, id):
        book_obj = self.get_queryset().filter(id=id).first()
        serializer = self.get_serializer(book_obj, data=request.data, partial=True)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        else:
            return Response(serializer.errors)


class DestroyModelMixin(object):
    def destroy(self, request, id):
        book_obj = self.get_queryset().filter(id=id).first()
        book_obj.delete()
        return Response("")


class ListCreateAPIView(GenericAPIView, ListModelMixin, CreateModelMixin):
    pass

class RetrieveUpdateDestroyAPIView(GenericAPIView, RetrieveModelMixin, UpdateModelMixin, DestroyModelMixin):
    pass

# class BookView(GenericAPIView, ListModelMixin, CreateModelMixin):
class BookView(ListCreateAPIView):
    query_set = Book.objects.all()
    serializer_class = BookSerializer

    def get(self, request):
        # book_obj = Book.objects.first()
        # ret = BookSerializer(book_obj)
        # book_list = Book.objects.all()
        # book_list = self.get_queryset()
        # ret = self.get_serializer(book_list, many=True)
        # return Response(ret.data)
        return self.list(request)

    def post(self, request):
        # print(request.data)
        # serializer = BookSerializer(data=request.data)
        # if serializer.is_valid():
        #     serializer.save()
        #     return Response(serializer.data)
        # else:
        #     return Response(serializer.errors)
        return self.create(request)


# class BookEditView(GenericAPIView, RetrieveModelMixin, UpdateModelMixin, DestroyModelMixin):
class BookEditView(RetrieveUpdateDestroyAPIView):
    query_set = Book.objects.all()
    serializer_class = BookSerializer

    def get(self, request, id):
        # book_obj = Book.objects.filter(id=id).first()
        # ret = BookSerializer(book_obj)
        # return Response(ret.data)
        return self.retrieve(request, id)

    def put(self, request, id):
        # book_obj = Book.objects.filter(id=id).first()
        # serializer = BookSerializer(book_obj, data=request.data, partial=True)
        # if serializer.is_valid():
        #     serializer.save()
        #     return Response(serializer.data)
        # else:
        #     return Response(serializer.errors)
        return self.update(request, id)

    def delete(self, request, id):
        # book_obj = Book.objects.filter(id=id).first()
        # book_obj.delete()
        # return Response("")
        return self.destroy(request, id)



# class ViewSetMixin(object):
#     def as_view(self):
#         """
#         按照我们参数指定的去匹配
#         get-->list
#         :return:
#         """


from rest_framework.viewsets import ViewSetMixin    #必须继承ViewSetMixin，路由的as_view方法才可以传参


class ModelViewSet(ViewSetMixin, GenericAPIView, ListModelMixin, CreateModelMixin, RetrieveModelMixin, UpdateModelMixin, DestroyModelMixin):
    pass


#上面封装的所有框架都帮我们封装好了
#from rest_framework.viewsets import ModelViewSet
#注意：用框架封装的视图url上的那个关键字参数要用pk系统默认的

class BookModelViewSet(ModelViewSet):
    queryset = Book.objects.all()
    serializer_class = BookSerializer

自己封装ModelViewSet

from rest_framework import views
from rest_framework import generics
from rest_framework import mixins
from rest_framework import viewsets


from bms import models
from rest_framework.response import Response
from rest_framework.views import APIView
from bms.modelserializers import BookModelSerializer, PublisherModelSerializer, AuthorModelSerializer


class BookListView(APIView):
    def get(self, request):
        # 1. 查出所有的书籍信息
        queryset = models.Book.objects.all()  # [Book_obj1, Book_obj2, ...]
        # 2. 使用serizlizer序列化
        ser_obj = BookModelSerializer(queryset, many=True)  # [obj1, obj2, obj3, ...]
        return Response(ser_obj.data)  #

    def post(self, request):
        # 2. 对数据做有效性校验
        ser_obj = BookModelSerializer(data=request.data)
        if ser_obj.is_valid():
            ser_obj.save()  # 调用的是BookSerializer类中的create方法，需要自己去实现
            # 3. 拿到序列化的数据去数据库创建新记录
            return Response("ok")
        else:
            return Response(ser_obj.errors)


class BookDetailView(APIView):
    """这是书籍详情相关的接口 支持：GET/PUT/DELETE"""
    def get(self, request, pk):
        """获取具体某本书的信息"""
        # 1. 根据pk去查询具体的那本书籍对象
        book_obj = models.Book.objects.filter(pk=pk).first()
        if book_obj:
            # 2. 将书籍对象 序列化成 json格式的数据
            ser_obj = BookModelSerializer(book_obj)
            # 3. 返回响应
            return Response(ser_obj.data)
        else:
            return Response("无效的书籍id")

    def put(self, request, pk):
        """修改具体某一本书"""
        # 1. 根据pk去查询具体的那本书籍对象
        book_obj = models.Book.objects.filter(pk=pk).first()
        if book_obj:
            # 2. 获取用户 发送过来的数据并且更新对象
            ser_obj = BookModelSerializer(instance=book_obj, data=request.data, partial=True)  # form组件中也有类似的实现
            if ser_obj.is_valid():
                # 3. 保存并返回修改后的数据
                ser_obj.save()
                return Response(ser_obj.data)
            else:
                return Response(ser_obj.errors)
        else:
            return Response("无效的书籍id")

    def delete(self, request, pk):
        """删除具体某一本书"""
        # 1. 根据pk去查询具体的那本书籍对象
        book_obj = models.Book.objects.filter(pk=pk)
        if book_obj:
            # 删除书籍对象
            book_obj.delete()
            return Response("删除成功")
        else:
            return Response("无效的书籍id")


#####################进化
class GenericAPIView(APIView):
    """把视图中可能用到的配置和方法封装起来"""
    queryset = None
    serializer_class = None

    def get_queryset(self, request, *args, **kwargs):
        ######### 让每次请求来的时候都现查一次数据
        return self.queryset.all()

    def get_object(self, request, pk, *args, **kwargs):
        return self.get_queryset(request, *args, **kwargs).filter(pk=pk).first()


# python mixin（混合类）:不能单独使用，和其它类搭配起来使用（利用了Python支持多继承）
class ListModelMixin(object):
    def list(self, request, *args, **kwargs):  ##get
        queryset = self.get_queryset()
        ser_obj = self.serializer_class(queryset, many=True)
        return Response(ser_obj.data)


class CreateModelMixin(object):
    def create(self, request, *args, **kwargs):  ##post
        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)

# 获取具体某一条记录
class RetrieveModelMixin(object):
    def retrieve(self, request, pk, *args, **kwargs):  ##get
        obj = self.get_object(request, pk, *args, **kwargs)
        if obj:
            # 2. 将书籍对象 序列化成 json格式的数据
            ser_obj = self.serializer_class(obj)
            # 3. 返回响应
            return Response(ser_obj.data)
        else:
            return Response("无效的id")


class UpdateModelMixin(object):
    def update(self, request, pk, *args, **kwargs):   ##put
        obj = self.get_object(request, pk, *args, **kwargs)
        if obj:
            ser_obj = self.serializer_class(instance=obj, data=request.data, partial=True)  # form组件中也有类似的实现
            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 DestroyModelMixin(object):
    def destroy(self, request, pk, *args, **kwargs):   ##delete
        obj = self.get_object(request, pk, *args, **kwargs)
        if obj:
            obj.delete()
            return Response("删除成功")
        else:
            return Response("无效的id")


# 出版社
class PublisherListView(GenericAPIView, ListModelMixin, CreateModelMixin):
    queryset = models.Publisher.objects.all()
    serializer_class = PublisherModelSerializer

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

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


class PublisherDetailView(GenericAPIView, RetrieveModelMixin, UpdateModelMixin, DestroyModelMixin):
    queryset = models.Publisher.objects.all()
    serializer_class = PublisherModelSerializer

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

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

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


#####################超进化##两个视图

class CreateAPIView(CreateModelMixin,GenericAPIView):
    def post(self, request, *args, **kwargs):
        return self.create(request, *args, **kwargs)


class ListAPIView(ListModelMixin,GenericAPIView):
    def get(self, request, *args, **kwargs):
        return self.list(request, *args, **kwargs)


class RetrieveAPIView(RetrieveModelMixin,GenericAPIView):
    def get(self, request, pk, *args, **kwargs):
        return self.retrieve(request, pk, *args, **kwargs)

class DestroyAPIView(DestroyModelMixin,GenericAPIView):
    def delete(self, request, pk, *args, **kwargs):
        return self.destroy(request, pk, *args, **kwargs)

class UpdateAPIView(UpdateModelMixin,GenericAPIView):
    def put(self, request, pk, *args, **kwargs):
        return self.update(request, pk, *args, **kwargs)

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


class AuthorDetailView(RetrieveAPIView,DestroyAPIView,UpdateAPIView):
    queryset = models.Author.objects.all()
    serializer_class = AuthorModelSerializer


##########最终######一个视图搞定####必须继承ViewSetMixin，路由的as_view方法才可以传参

##配合url##actions
urlpatterns = [

    # url(r'publishers/$', views.PublisherListView.as_view()),  # 出版社列表
    # url(r'publishers/(?P<pk>\d+)/$', views.PublisherDetailView.as_view()),  # 出版社详情
    #
    # url(r'authors/$', views.AuthorListView.as_view()),  # 作者列表
    # url(r'authors/(?P<pk>\d+)/$', views.AuthorDetailView.as_view()),  # 作者详情

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

]

# 或者
from rest_framework.routers import DefaultRouter

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

urlpatterns += router.urls

##########

from rest_framework.viewsets import GenericViewSet
class ViewSetMixin(object):
    def as_view(cls, actions=None, **initkwargs):
      # ...
      pass


class GenericViewSet(ViewSetMixin, GenericAPIView):
    pass


class AuthorViewSet(GenericViewSet,CreateModelMixin,RetrieveModelMixin,UpdateModelMixin,DestroyModelMixin,ListModelMixin):
    """
        list()
        create()
        retrieve()
        update()
        destroy()

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





#########################rest_framework###############################
class ModelViewSet(mixins.CreateModelMixin,
                   mixins.RetrieveModelMixin,
                   mixins.UpdateModelMixin,
                   mixins.DestroyModelMixin,
                   mixins.ListModelMixin,
                   GenericViewSet):
    pass


from rest_framework.viewsets import ModelViewSet
class AuthorViewSet(ModelViewSet):
    """
        list()
        create()
        retrieve()
        update()
        destroy()

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

视图进化

DRF的路由

from django.urls import path, include
from .views import BookView, BookEditView, BookModelViewSet
from rest_framework.routers import DefaultRouter
router = DefaultRouter()
router.register(r"book", BookModelViewSet)
urlpatterns = [
    # path('list', BookView.as_view()),
    # path('retrieve/<int:id>', BookEditView.as_view()),
    #path('list', BookModelViewSet.as_view({"get": "list", "post": "create"})),
    #path('retrieve/<int:pk>', BookModelViewSet.as_view({"get": "retrieve", "put": "update", "delete": "destroy"})),
]
urlpatterns += router.urls

#通过框架可以把路由视图都变的非常简单
#但是需要自定制的时候还是需要用APIView写,当不需要那么多路由的时候,也不要用这种路由注册.

app01中urls.py

DRF的版本

随着项目的更新,版本就越来越多,不可能新的版本出了,以前旧的版本就不进行维护了,就需要对版本进行控制了

一、源码查找

APIView返回View中的view函数，然后调用dispatch方法,APIView的dispatch方法

执行self.initial方法之前是各种赋值，包括request的重新封装赋值

 def dispatch(self, request, *args, **kwargs):
        """
        `.dispatch()` is pretty much the same as Django's regular dispatch,
        but with extra hooks for startup, finalize, and exception handling.
        """
        self.args = args
        self.kwargs = kwargs
        request = self.initialize_request(request, *args, **kwargs)
        self.request = request
        self.headers = self.default_response_headers  # deprecate?

        try:
            self.initial(request, *args, **kwargs)   #####
            ...
def initial(self, request, *args, **kwargs):
            """
            Runs anything that needs to occur prior to calling the method handler.
            """
            self.format_kwarg = self.get_format_suffix(**kwargs)

            # Perform content negotiation and store the accepted info on the request
            neg = self.perform_content_negotiation(request)
            request.accepted_renderer, request.accepted_media_type = neg

            # Determine the API version, if versioning is in use.
            # 版本控制
            # self.determine_version 这个方法是找我们自己定义的版本控制类，没有的话返回(None,None)
            version, scheme = self.determine_version(request, *args, **kwargs)
            request.version, request.versioning_scheme = version, scheme
            ###version版本信息赋值给了 request.version  版本控制方案赋值给了 request.versioning_scheme
            ###其实这个版本控制方案~就是我们配置的版本控制的类,也就是说，APIView通过这个方法初始化自己提供的组件
            ###接下来看看框架提供了哪些版本的控制方法在rest_framework.versioning里,from rest_framework import versioning

            # Ensure that the incoming request is permitted
            # 认证 权限 频率组件
            self.perform_authentication(request)
            self.check_permissions(request)
            self.check_throttles(request)


...

    def determine_version(self, request, *args, **kwargs):
        """
        If versioning is being used, then determine any API version for the
        incoming request. Returns a two-tuple of (version, versioning_scheme)
        """
        if self.versioning_class is None:
            return (None, None)
        #scheme是我们配置的版本控制类的实例化对象
        scheme = self.versioning_class()
        #返回值scheme.determine_version  MyVersion中必须定义determine_version这个方法,从上面可以看出此方法返回版本号version
        return (scheme.determine_version(request, *args, **kwargs), scheme)

源码查找

二、使用方法1（URL上携带版本信息的配置）

第1步:settings.py

REST_FRAMEWORK = {
    # 默认使用的版本控制类
    'DEFAULT_VERSIONING_CLASS': 'rest_framework.versioning.URLPathVersioning',
    # 允许的版本
    'ALLOWED_VERSIONS': ['v1', 'v2'],
    # 版本使用的参数名称
    'VERSION_PARAM': 'version',
    # 默认使用的版本
    'DEFAULT_VERSION': 'v1',
}

settings.py

第2步:app01中urls.py

urlpatterns = [
    url(r"^(?P<version>[v1|v2]+)/test01", TestView.as_view()),
]

app01.urls.py

第3步:测试视图app01.views.py

class TestView(APIView):
    def get(self, request, *args, **kwargs):
        print(request.versioning_scheme)
        ret = request.version
        if ret == "v1":
            return Response("版本v1的信息")
        elif ret == "v2":
            return Response("版本v2的信息")
        else:
            return Response("根本就匹配不到这个路由")

app01.views.py

三、使用方法2(URL过滤条件配置版本信息)

第1步:settings.py

REST_FRAMEWORK = {
    "DEFAULT_VERSIONING_CLASS": "utils.version.MyVersion",
    # "DEFAULT_VERSIONING_CLASS": "rest_framework.versioning.QueryParameterVersioning",
    "DEFAULT_VERSION": "v1",
    "ALLOWED_VERSIONS": ['v1', 'v2'],
    "VERSION_PARAM": "version"
}

settings.py

第2步:app01中urls.py

from django.urls import path, include
from .views import DemoView

urlpatterns = [
    path(r"", DemoView.as_view()),
]

app01中urls.py

第3步:utils中version.py

from rest_framework import versioning
class MyVersion(object):
    def determine_version(self, request, *args, **kwargs):
        # 返回值 给了request.version
        # 返回版本号
        # 版本号携带在过滤条件 xxxx?version=v1中，版本号在那就去那取值
        version = request.query_params.get("version", "v1")
        return version

View Code

第4步:测试视图app01.views.py

from rest_framework.views import APIView
from rest_framework.response import Response

class DemoView(APIView):
    def get(self, request):
        print(request.version)
        print(request.versioning_scheme)
        # 得到版本号  根据版本号的不同返回不同的信息
        if request.version == "v1":
            return Response("v1版本的数据")
        elif request.version == "v2":
            return Response("v2版本的数据")
        return Response("不存在的版本")

app01.views.py

DRF的认证

每次给服务器发请求，由于Http的无状态，导致每次都是新的请求,
服务端需要对每次来的请求进行认证，看用户是否登录，以及登录用户是谁,
服务器对每个请求进行认证的时候，不可能在每个视图函数中都写认证,
一定是把认证逻辑抽离出来,以前我们可能会加装饰器或者中间件。

一、源码查找

 def dispatch(self, request, *args, **kwargs):
        """
        `.dispatch()` is pretty much the same as Django's regular dispatch,
        but with extra hooks for startup, finalize, and exception handling.
        """
        self.args = args
        self.kwargs = kwargs
        request = self.initialize_request(request, *args, **kwargs)
        self.request = request
        self.headers = self.default_response_headers  # deprecate?

        try:
            self.initial(request, *args, **kwargs)

            # Get the appropriate handler method
            if request.method.lower() in self.http_method_names:
                handler = getattr(self, request.method.lower(),
                                  self.http_method_not_allowed)
            else:
                handler = self.http_method_not_allowed

            response = handler(request, *args, **kwargs)

        except Exception as exc:
            response = self.handle_exception(exc)

        self.response = self.finalize_response(request, response, *args, **kwargs)
        return self.response

...
    def initialize_request(self, request, *args, **kwargs):
        """
        Returns the initial request object.
        """
        parser_context = self.get_parser_context(request)

        return Request(
            request,
            parsers=self.get_parsers(),
            authenticators=self.get_authenticators(),
            negotiator=self.get_content_negotiator(),
            parser_context=parser_context
        )


    def initial(self, request, *args, **kwargs):
        """
        Runs anything that needs to occur prior to calling the method handler.
        """
        self.format_kwarg = self.get_format_suffix(**kwargs)

        # Perform content negotiation and store the accepted info on the request
        neg = self.perform_content_negotiation(request)
        request.accepted_renderer, request.accepted_media_type = neg

        # Determine the API version, if versioning is in use.
        # 版本控制
        # self.determine_version 这个方法是找我们自己定义的版本控制类，没有的话返回(None,None)
        version, scheme = self.determine_version(request, *args, **kwargs)
        request.version, request.versioning_scheme = version, scheme

        # Ensure that the incoming request is permitted
        # 认证 权限 频率组件
        self.perform_authentication(request)
        self.check_permissions(request)
        self.check_throttles(request)

...
    def perform_authentication(self, request):
        """
        Perform authentication on the incoming request.

        Note that if you override this and simply 'pass', then authentication
        will instead be performed lazily, the first time either
        `request.user` or `request.auth` is accessed.
        """
        request.user
...
#去类Request中找user        

    @property
    def user(self):
        """
        Returns the user associated with the current request, as authenticated
        by the authentication classes provided to the request.
        """
        if not hasattr(self, '_user'):
            with wrap_attributeerrors():
                #__enter__
                self._authenticate()
                #__exit__
        return self._user
...

    def _authenticate(self):
        """
        Attempt to authenticate the request using each authentication instance
        in turn.
        """
        #这里的authentications是最开始实例化Request类的时候传过来的
        #是调用get_authenticators这个方法，
        # 这个方法的返回值是 return [auth() for auth in self,authentication_classes]
        #authentication_classes如果我们配置了就用我们配置的，否则就从默认配置文件中读取配置类
        #返回的auth()是认证类实例化后的
        for authenticator in self.authenticators:   #查看authenticators
            try:
                #也就是说这里的authenticator是认证类实例化后的
                #authenticate方法是我们必须去实现的方法
                #authenticate的参数self,我们是通过新的request.user进来的，所以这个self就是新的request
                user_auth_tuple = authenticator.authenticate(self)
            except exceptions.APIException:
                self._not_authenticated()
                raise

            if user_auth_tuple is not None:
                self._authenticator = authenticator
                #request.user
                #request.auth
                self.user, self.auth = user_auth_tuple
                return

        self._not_authenticated()

...
class Request(object):

    def __init__(self, request, parsers=None, authenticators=None,
                 negotiator=None, parser_context=None):
        assert isinstance(request, HttpRequest), (
            'The `request` argument must be an instance of '
            '`django.http.HttpRequest`, not `{}.{}`.'
            .format(request.__class__.__module__, request.__class__.__name__)
        )

        self._request = request
        self.parsers = parsers or ()
        self.authenticators = authenticators or ()
        ## authenticators看传参了么
...

    def initialize_request(self, request, *args, **kwargs):
        """
        Returns the initial request object.
        """
        parser_context = self.get_parser_context(request)

        return Request(
            request,
            parsers=self.get_parsers(),
            authenticators=self.get_authenticators(),  #传参了
            negotiator=self.get_content_negotiator(),
            parser_context=parser_context
        )

...

    def get_authenticators(self):
        """
        Instantiates and returns the list of authenticators that this view can use.
        """
        #self.authentication_classes去配置文件拿所有的认证类
        return [auth() for auth in self.authentication_classes]

源码查找

APIView的dispatch方法里给request重新赋值了
APIView的dispatch方法里给执行了initial方法，初始化了版本认证，权限，频率组件，initial方法的参数request是重新赋值后的
权限组件返回的是request.user，initial的request是重新赋值之后的，所以这里的request是重新赋值之后的，也就是Request类实例对象，那这个user一定是一个静态方法.

二、使用方法

1、app01中models.py

# 先在model中注册模型类
# 并且进行数据迁移

from django.db import models

class User(models.Model):

    username = models.CharField(max_length=32)
    pwd = models.CharField(max_length=16)
    token = models.UUIDField()

app01中models.py

2、app01中urls.py

from django.urls import path
from .views import DemoView, LoginView, TestView


urlpatterns = [
    path(r"login", LoginView.as_view()),
    path(r"test", TestView.as_view()),
]

app01中urls.py

3、app01中views.py

import uuid
from app01 import models
from utils.auth import MyAuth

from rest_framework.views import APIView
from rest_framework.response import Response


class LoginView(APIView):
    def post(self, request):
        username = request.data.get("username")
        pwd = request.data.get("pwd")
        if username and pwd:
            obj = models.User.objects.filter(username=username, pwd=pwd).first()
            if obj:
                token = uuid.uuid4()
                obj.token = token
                obj.save()
                return Response({'error_no': 0, 'token': token})
            else:
                return Response("用户名密码错误")
        return Response("用户名密码不能为空")


# 局部视图认证
class TestView(APIView):
    authentication_classes = [MyAuth, ]

    def get(self, request):
        print(request.user)
        print(request.auth)
        user_id = request.user.id
        return Response("认证测试")

app01中views.py

4、utils中auth.py 写一个认证的类

from rest_framework.exceptions import AuthenticationFailed
from app01.models import User
from rest_framework.authentication import BaseAuthentication


class MyAuth(BaseAuthentication):

    def authenticate(self, request):
        # 做认证 看他是否登录
        # 拿到token，此处是从url过滤条件里拿到token
        # 去数据库看token是否合法
        # 合法的token能够获取用户信息
        token = request.query_params.get("token", "")
        if not token:
            raise AuthenticationFailed("没有携带token")
        user_obj = User.objects.filter(token=token).first()
        if not user_obj:
            raise AuthenticationFailed("token不合法")
        # return (None, None)  
        return (user_obj, token) #第1个返回值是request.user 第2个返回值是request.auth

utils中auth.py

5、全局配置认证

REST_FRAMEWORK = {
    # "DEFAULT_VERSIONING_CLASS": "utils.version.MyVersion",
    "DEFAULT_VERSIONING_CLASS": "rest_framework.versioning.QueryParameterVersioning",
    "DEFAULT_VERSION": "v1",
    "ALLOWED_VERSIONS": "v1, v2",
    "VERSION_PARAM": "ver",
    # "DEFAULT_AUTHENTICATION_CLASSES": ["utils.auth.MyAuth", ]  #全局配置
}

settings.py

DRF的权限

对某件事情决策的范围和程度叫做权限

一、源码查找

    def check_permissions(self, request):
        """
        Check if the request should be permitted.
        Raises an appropriate exception if the request is not permitted.
        """
        for permission in self.get_permissions():
            #permission我们写的权限类的实例对象 MyPermission()
            if not permission.has_permission(request, self):
                #permission_denied是抛出异常的
                #也就是说我们的权限类中必须有has_permission这个方法，否则就抛出异常
                self.permission_denied(
                     #message 定义异常信息
                    request, message=getattr(permission, 'message', None)
                )

源码查找

权限类一定要有has_permission方法,否则就会抛出异常,这也是框架提供的钩子
rest_framework.permissions这个文件中存放了框架提供的所有权限的方法
BasePermission 这个是写权限类继承的一个基础权限类
Python代码是一行一行执行的,那么执行initial方法初始化这些组件的时候也是有顺序的,版本在前面然后是认证，然后是权限最后是频率
版本，认证，权限，频率这几个组件的源码是一个流程

二、使用方法

1、app01中models.py

# 先在model中注册模型类
# 并且进行数据迁移

from django.db import models

class User(models.Model):

    username = models.CharField(max_length=32)
    pwd = models.CharField(max_length=16)
    token = models.UUIDField()
    type = models.IntegerField(choices=((1, "vip"), (2, "vvip"), (3, "普通")), default=3)

app01中models.py

2、app01中urls.py

from django.urls import path
from .views import DemoView, LoginView, TestView


urlpatterns = [
    path(r"login", LoginView.as_view()),
    path(r"test", TestView.as_view()),
]

app01中urls.py

3、app01中views.py

import uuid
from .models import User
from utils.auth import MyAuth
from utils.permission import MyPermission
# Create your views here.

from rest_framework.views import APIView
from rest_framework.response import Response


class DemoView(APIView):
    def get(self, request):
        return Response("认证demo~")


class LoginView(APIView):

    def post(self, request):
        username = request.data.get("username")
        pwd = request.data.get("pwd")
        # 登录成功 生成token 会把token给你返回
        token = uuid.uuid4()
        User.objects.create(username=username, pwd=pwd, token=token)
        return Response("创建用户成功")


class TestView(APIView):
    authentication_classes = [MyAuth,]
    permission_classes = [MyPermission, ]  #局部配置权限

    def get(self, request):
        print(request.user)
        print(request.auth)
        user_id = request.user.id
        return Response("认证测试")

app01中views.py

4、utils中permission.py 写一个权限类

from rest_framework.permissions import BasePermission

class MyPermission(BasePermission):
    message = "您没有权限"

    def has_permission(self, request, view):
        # request.user:当前经过认证的用户对象，
        # 如果没有认证 request.user 就是匿名用户
        if not request.user:
            # 认证没有通过
            return False
        # 判断用户是否有权限
        if request.user.type == 1:
            return True
        else:
            return False

utils中permission.py

5、全局配置权限

REST_FRAMEWORK = {
    # "DEFAULT_VERSIONING_CLASS": "utils.version.MyVersion",
    "DEFAULT_VERSIONING_CLASS": "rest_framework.versioning.QueryParameterVersioning",
    "DEFAULT_VERSION": "v1",
    "ALLOWED_VERSIONS": "v1, v2",
    "VERSION_PARAM": "ver",
    # "DEFAULT_AUTHENTICATION_CLASSES": ["utils.auth.MyAuth", ]  #全局配置
}
REST_FRAMEWORK = {
    # "DEFAULT_VERSIONING_CLASS": "utils.version.MyVersion",
    # 默认使用的版本控制类
    'DEFAULT_VERSIONING_CLASS': 'rest_framework.versioning.URLPathVersioning',
    # 允许的版本
    "ALLOWED_VERSIONS": "v1, v2",
    # 版本使用的参数名称
     "VERSION_PARAM": "ver",
    # 默认使用的版本
    'DEFAULT_VERSION': 'v1',
    # 配置全局认证
    # "DEFAULT_AUTHENTICATION_CLASSES": ["utils.auth.MyAuth", ]  #全局配置
    # 配置全局权限
    "DEFAULT_PERMISSION_CLASSES": ["utils.permission.MyPermission"]
}

settings.py

DRF的频率

开放平台的API接口调用需要限制其频率，以节约服务器资源和避免恶意的频繁调用。

一、源码查找

    def check_throttles(self, request):
        """
        Check if request should be throttled.
        Raises an appropriate exception if the request is throttled.
        """
        #throttle 配置每个频率控制类的实例化对象   allow_request方法和wait方法
        for throttle in self.get_throttles():
            if not throttle.allow_request(request, self):
                self.throttled(request, throttle.wait())

...
    def get_throttles(self):
        """
        Instantiates and returns the list of throttles that this view uses.
        """
        return [throttle() for throttle in self.throttle_classes]

源码查找

二、频率组件原理

DRF中的频率控制基本原理是基于访问次数和时间的，当然也可以通过自己定义的方法来实现。

当请求进来，走到频率组件的时候，DRF内部会有一个字典来记录访问者的IP，

以这个访问者的IP为key，value为一个列表，存放访问者每次访问的时间，

{  IP1: [第三次访问时间，第二次访问时间，第一次访问时间]，}

把每次访问最新时间放入列表的最前面，记录这样一个数据结构后，通过什么方式限流呢~~

如果我们设置的是10秒内只能访问5次，

　　-- 1，判断访问者的IP是否在这个请求IP的字典里

　　-- 2，保证这个列表里都是最近10秒内的访问的时间

　　　　　　判断当前请求时间和列表里最早的(也就是最后的)请求时间的查

　　　　　　如果差大于10秒，说明请求以及不是最近10秒内的，删除掉，

　　　　　　继续判断倒数第二个，直到差值小于10秒

　　-- 3，判断列表的长度(即访问次数)，是否大于我们设置的5次，

　　　　　　如果大于就限流，否则放行，并把时间放入列表的最前面。

三、使用方法

1、app01中views.py

import uuid
from .models import User
from utils.auth import MyAuth
from utils.permission import MyPermission
from utils.throttle import MyThrottle
# Create your views here.

from rest_framework.views import APIView
from rest_framework.response import Response

class LoginView(APIView):

    def post(self, request):
        username = request.data.get("username")
        pwd = request.data.get("pwd")
        # 登录成功 生成token 会把token给你返回
        token = uuid.uuid4()
        User.objects.create(username=username, pwd=pwd, token=token)
        return Response("创建用户成功")


class TestView(APIView):
    authentication_classes = [MyAuth,]
    permission_classes = [MyPermission, ]
    throttle_classes = [MyThrottle, ]

    def get(self, request):
        print(request.user)
        print(request.auth)
        user_id = request.user.id
        return Response("认证测试")

app01中views.py

2、utils中throttle.py 写一个频率类

from rest_framework.throttling import BaseThrottle, SimpleRateThrottle
import time

VISIT_RECORD = {}

#自定义的频率限制类

# class MyThrottle(BaseThrottle):
#
#     def __init__(self):
#         self.history = None
#
#     def allow_request(self, request, view):
#         # 实现限流的逻辑
#         # 以IP限流
#         # 访问列表 {IP: [time1, time2, time3]}
#         # 1, 获取请求的IP地址
#         ip = request.META.get("REMOTE_ADDR")
#         # 2，判断IP地址是否在访问列表
#         now = time.time()
#         if ip not in VISIT_RECORD:
#             # --1， 不在 需要给访问列表添加key，value
#             VISIT_RECORD[ip] = [now,]
#             return True
#             # --2 在 需要把这个IP的访问记录 把当前时间加入到列表
#         history = VISIT_RECORD[ip]
#         history.insert(0, now)
#         # 3， 确保列表里最新访问时间以及最老的访问时间差 是1分钟
#         while history and history[0] - history[-1] > 60:
#             history.pop()
#         self.history = history
#         # 4，得到列表长度，判断是否是允许的次数
#         if len(history) > 3:
#             return False
#         else:
#             return True
#
#     def wait(self):
#         # 返回需要再等多久才能访问
#         time = 60 - (self.history[0] - self.history[-1])
#         return time

#使用自带的频率限制类
class MyThrottle(SimpleRateThrottle):
    scope = "WD"

    def get_cache_key(self, request, view):
        # 如果以IP地址做限流返回IP地址
        key = self.get_ident(request)
        return key

utils中throttle.py

3、全局配置频率

REST_FRAMEWORK = {
    # "DEFAULT_VERSIONING_CLASS": "utils.version.MyVersion",
    "DEFAULT_VERSIONING_CLASS": "rest_framework.versioning.QueryParameterVersioning",
    "DEFAULT_VERSION": "v1",
    "ALLOWED_VERSIONS": "v1, v2",
    "VERSION_PARAM": "ver",
    # "DEFAULT_AUTHENTICATION_CLASSES": ["utils.auth.MyAuth", ]  #全局配置
}
REST_FRAMEWORK = {
    # "DEFAULT_VERSIONING_CLASS": "utils.version.MyVersion",
    # 默认使用的版本控制类
    'DEFAULT_VERSIONING_CLASS': 'rest_framework.versioning.URLPathVersioning',
    # 允许的版本
    "ALLOWED_VERSIONS": "v1, v2",
    # 版本使用的参数名称
     "VERSION_PARAM": "ver",
    # 默认使用的版本
    'DEFAULT_VERSION': 'v1',
    # 配置全局认证
    # "DEFAULT_AUTHENTICATION_CLASSES": ["utils.auth.MyAuth", ]  #全局配置
    # 配置全局权限
    "DEFAULT_PERMISSION_CLASSES": ["utils.permission.MyPermission"],
    # 配置自定义频率限制
    "DEFAULT_THROTTLE_CLASSES": ["Throttle.throttle.MyThrottle"],
    # 配置频率限制
    "DEFAULT_THROTTLE_RATES": {
        "WD": "3/m"   #速率配置每分钟不能超过3次访问，WD是scope定义的值，
    }
}

settings.py

DRF的分页组件

DRF提供的三种分页: from rest_framework.pagination import PageNumberPagination, LimitOffsetPagination, CursorPagination
全局配置: REST_FRAMEWORK = { 'PAGE_SIZE': 2 }
第1种 PageNumberPagination 看第n页，每页显示n条数据 http://127.0.0.1:8000/book?page=2&size=1
第2种 LimitOffsetPagination 在第n个位置向后查看n条数据 http://127.0.0.1:8000/book?offset=2&limit=1
第3种 CursorPagination 加密游标的分页把上一页和下一页的id记住 http://127.0.0.1:8000/book?page=2&size=1

一、utils中pagination.py(自定义分页类)

from rest_framework.pagination import PageNumberPagination, LimitOffsetPagination, CursorPagination

# class MyPagination(PageNumberPagination):
#     # xxxx?page=1&size=2
#     page_size = 1  # 每页显示多少条
#     page_query_param = "page"   # URL中页码的参数
#     page_size_query_param = "size"  # URL中每页显示条数的参数
#     max_page_size = 3    # 最大页码数限制

# class MyPagination(LimitOffsetPagination):
#     # xxxx?offset=120&limit=20  #从第120条开始往后查20条数据
#     default_limit = 1
#     limit_query_param = "limit"
#     offset_query_param = "offset"
#     max_limit = 3

class MyPagination(CursorPagination):
    #
    cursor_query_param = "cursor"
    page_size = 2
    ordering = "-id" #

utils中pagination.py

二、app01中views.py

from django.shortcuts import render
from rest_framework.views import APIView
from rest_framework.response import Response
from SerDemo.models import Book
from SerDemo.serializers import BookSerializer

# Create your views here.
from rest_framework import pagination
from utils.pagination import MyPagination
from rest_framework.generics import GenericAPIView
from rest_framework.mixins import ListModelMixin


# class BookView(APIView):
#
#     def get(self, request):
#         queryset = Book.objects.all()
#         # 1,实例化分页器对象
#         page_obj = MyPagination()
#         # 2，调用分页方法去分页queryset
#         page_queryset = page_obj.paginate_queryset(queryset, request, view=self)
#         # 3，把分页好的数据序列化返回
#         # 4, 带着上一页下一页连接的响应
#         ser_obj = BookSerializer(page_queryset, many=True)
#         # 返回带超链接 需返回的时候用内置的响应方法
#         return page_obj.get_paginated_response(ser_obj.data)


class BookView(GenericAPIView, ListModelMixin):
    queryset = Book.objects.all()
    serializer_class = BookSerializer
    pagination_class = MyPagination
    # self.paginate_queryset(queryset)

    def get(self, request):
        return self.list(request)

app01中views.py

三、全局配置

REST_FRAMEWORK = {
    'DEFAULT_PAGINATION_CLASS': 'rest_framework.pagination.LimitOffsetPagination',
    'PAGE_SIZE': 20  #每页显示的数量
}

settings.py

DRF的解析器

解析器的作用就是服务端接收客户端传过来的数据，把数据解析成自己想要的数据类型的过程。本质就是对请求体中的数据进行解析。
在了解解析器之前要先知道Accept以及ContentType请求头。
Accept是告诉对方能解析什么样的数据，通常也可以表示想要什么样的数据。
ContentType是告诉对方我给你的是什么样的数据类型。
解析器工作原理的本质就是拿到请求的ContentType来判断前端给后端数据类型是什么，然后后端去拿相应的解析器去解析数据。

from django.core.handlers.wsgi import WSGIRequest

一、Django的解析器

请求进来请求体中的数据在request.body中，那也就证明，解析器会把解析好的数据放入request.body
在视图中可以打印request的类型，能够知道request是WSGIRequest这个类。
application/x-www-form-urlencoded不是不能上传文件，是只能上传文本格式的文件
multipart/form-data是将文件以二进制的形式上传，这样可以实现多种类型的文件上传一个解析到request.POST, request.FILES中。
也就是说之前能在request中能到的各种数据是因为用了不同格式的数据解析器
Django只能解析cont_type=multipart/form-data 和cont_type=application/x-www-form-urlencoded的数据，不能解析json

二、DRF的解析器

在request.data拿数据的时候解析器会被调用

四、DRF的解析器使用方法

1、app01中views.py

from django.shortcuts import render
from django.views import View
from django.http import HttpResponse
from django.core.handlers.wsgi import WSGIRequest
from rest_framework.views import APIView
from rest_framework.response import Response
from rest_framework.negotiation import DefaultContentNegotiation
from rest_framework import parsers

# Create your views here.


class DjangoView(View):
    def get(self, request):
        print(type(request))
        # Request
        # request.GET
        # request.POST
        # json request.body
        return HttpResponse("django解析器测试~~")


class DRFView(APIView):
    #parser_classes = [parsers.JSONParser, ]  #一般不配置

    def get(self, request):
        # request 重新封装的request  Request
        # request.data
        #
        return Response("DRF解析器的测试~~")

app01中views.py

DRF的渲染器

渲染器就是友好的展示数据,我们在浏览器中展示的DRF测试的那个页面就是通过浏览器的渲染器来做到的,当然我们可以展示Json数据类型

DEFAULTS = {
    # Base API policies
    'DEFAULT_RENDERER_CLASSES': (
        'rest_framework.renderers.JSONRenderer',
        'rest_framework.renderers.BrowsableAPIRenderer',
    ),

DRF的渲染器

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原文地址：https://www.cnblogs.com/bubu99/p/10487215.html

Django REST framework 1

Django REST framework

DRF序列化

DRF反序列化

一、Serializer

1、声明序列化类（app01中serializers.py）

2、用声明的序列化类去序列化(app01中views.py)

二、ModelSerializer

1、定义一个ModelSerializer序列化器（app01中serializers.py）

三、Serializer和ModelSerializer的区别

四、JsonResponse和Django序列化

DRF的视图

一、源码查找

二、ModelViewSet

DRF的路由

DRF的版本

一、源码查找

二、使用方法1（URL上携带版本信息的配置）

第1步:settings.py

第2步:app01中urls.py

第3步:测试视图app01.views.py

三、使用方法2(URL过滤条件配置版本信息)

第1步:settings.py

第2步:app01中urls.py

第3步:utils中version.py

第4步:测试视图app01.views.py

DRF的认证

一、源码查找

二、使用方法

1、app01中models.py

2、app01中urls.py

3、app01中views.py

4、utils中auth.py 写一个认证的类

5、全局配置认证

DRF的权限

一、源码查找

二、使用方法

1、app01中models.py

2、app01中urls.py

3、app01中views.py

4、utils中permission.py 写一个权限类

5、全局配置权限

DRF的频率

一、源码查找

二、频率组件原理

三、使用方法

1、app01中views.py

2、utils中throttle.py 写一个频率类

3、全局配置频率

DRF的分页组件

一、utils中pagination.py(自定义分页类)

二、app01中views.py

三、全局配置

DRF的解析器

一、Django的解析器

二、DRF的解析器

四、DRF的解析器使用方法

1、app01中views.py

DRF的渲染器