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python drf各类组件的用法和作用

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DRF组件的用法和作用 认证 自定义认证的类 """ from rest_framework.authentication import BaseAuthentication from rest_framework.exceptions import AuthenticationFailed from authapp.models import UserToken class MyOrderAuthentic

DRF组件的用法和作用

认证

	自定义认证的类
   """
   from rest_framework.authentication import BaseAuthentication
   from rest_framework.exceptions import AuthenticationFailed
   from authapp.models import UserToken
   class MyOrderAuthentication(BaseAuthentication):
      在这里实现认证的逻辑
     def authenticate(self, request):
       token = request._request.GET.get('token')
       # 获取到token之后,需要在数据库中查找token
       obj = UserToken.objects.filter(token=token).first()
       if not obj:
         # 没有通过认证
         raise AuthenticationFailed('认证失败')
       # 返回元组( user, auth )
       return (obj.user, obj)
   """
 
  使用局部配置(在视图函数中)
   """
   class OrderView(APIView):
     # 通过authentication_classes设置认证类
     authentication_classes = [MyOrderAuthentication,]
     # 通过authentication_classes设置为空列表,就不再进行认证了
     # authentication_classes = []
   """
 
  全局配置
   """
   REST_FRAMEWORK = {
     'DEFAULT_AUTHENTICATION_CLASSES':['unitls.authentication.MyOrderAuthentication'],
   }
   """
 
  设置匿名用户
   """
   REST_FRAMEWORK = {
     'UNAUTHENTICATED_USER': lambda :"匿名用户",
     'UNAUTHENTICATED_TOKEN': lambda :'123456',
   }
   """
 
  ## 最最重要的,理清认证的源代码

权限

 自定义权限类
  """
   from rest_framework.permissions import BasePermission
   class MyOrderPermission(BasePermission):
     #自定义权限认证的类,必须要实现has_permission方法
     message = '你不是超级用户,没有权限访问'
     def has_permission(self, request, view):
     
       #Return `True` if permission is granted, `False` otherwise.
       #返回True表示有权限访问,返回False表示没有权限访问
       if request.user.user_type != 3:
         return False
       return True
  """
 
  局部使用
  """
  class OrderView(APIView):
  
     # permission_classes设置权限类
     permission_classes = [MyOrderPermission,]
     # 通过authentication_classes设置为空列表,就不再进行权限认证了
     permission_classes = []
  """
 
  全局的设定
  """
  REST_FRAMEWORK = {
    'DEFAULT_PERMISSION_CLASSES':['unitls.permission.MyOrderPermission'],
  }
  """
  
  最最重要的,理清权限认证的源代码

分页

 自定义分页类PageNumberPagination
  # 自定制分页类
  class MyPageNumberPagination(PageNumberPagination):
    """http://127.0.0.1:8000/api/userpage/?page=1&pagesize=10"""
    # page_size每一返回多少条
    page_size = 5
    # 设置分页的参数名
    page_query_param = 'page'
    # 设置每页返回数据量的参数名
    page_size_query_param = 'pagesize'
    # 设置每页最大返回的条数
    max_page_size = 6
 
 使用
   class UsersPageView(APIView):
     
     def get(self,request,*args,**kwargs):
       # 获取表中所有用户的row(记录)
       obj = models.UserInfo.objects.all()
       #实例化分页的类
       #page_obj = PageNumberPagination()
       page_obj = MyPageNumberPagination()
       #获取分页数据
       page_data = page_obj.paginate_queryset( queryset=obj,request=request,view=self)
       # 序列化
       ser = UsersSerializer(instance=page_data,many=True)
 
       # return Response(ser.data)
       #get_paginated_response会返回上一页下一页和总条数
       return page_obj.get_paginated_response(ser.data)
 
  自定义分页类LimitOffsetPagination
  from rest_framework.pagination import LimitOffsetPagination
 
  class MyLimitOffsetPagination(LimitOffsetPagination):
    """http://127.0.0.1:8000/api/userpage/?limit=10&offset=0"""
    default_limit = 5
    limit_query_param = 'limit'
    offset_query_param = 'offset'
    max_limit = 7
 
  
  自定义分页类CursorPagination(会对分页参数进行加密)
  from rest_framework.pagination import CursorPagination
 
  class MyCursorPagination(CursorPagination):
    """http://127.0.0.1:8000/api/userpage/?cursor=cD01"""
    cursor_query_param = 'cursor'
    page_size = 4
    #返回数据市的排序的方式
    ordering = '-id'
    max_page_size = 8
 
   设置全局的分页
   """
     REST_FRAMEWORK = {
       'DEFAULT_PAGINATION_CLASS':'unitl.pagination.MyCursorPagination',
       'PAGE_SIZE':3
     }
   """

视图

 以前 (Django的View)
  """
    class MyView(View)
      .....
  """
 
  现在(rest_framework的APIView)
  """
    class MyView(APIView)
    .....
  """
  
  其他视图的使用
  第一个:GenericAPIView 视图的使用 (跟继承自APIViewq其实一样,只是我们在外面逻辑,
    GenericAPIView在内部c定制方法帮我们实现了)
  """
  from rest_framework.generics import GenericAPIView
  class BookinfoSeralizer(serializers.ModelSerializer):
    
    class Meta:
      model = models.BookInfo
      fields = "__all__"
  class BookView(GenericAPIView):
    # queryset: 设置获取的数据
    queryset = models.BookInfo.objects.all()
    # serializer_class: 设置序列化的类
    serializer_class = BookinfoSeralizer
    # pagination_class : 设置分页的类
    pagination_class = MyPageNumberPagination
    def get(self,request,*args,**kwargs):
      obj = self.get_queryset() #=> obj = models.BookInfo.objects.all()
      # 获取当前分页的数据
      page_data = self.paginate_queryset(obj) #=>page_obj = MyPageNumberPagination() #获取分页数据page_data = page_obj.paginate_queryset()
      # 获取序列化之后的数据
      ser = self.get_serializer(instance=page_data,many=True) #->ser = BookinfoSeralizer(instance=page_data,many=True)
      return Response(ser.data)
  """
    
   第二个:GenericViewSet 视图的如下使用,注意路由会发生变化
    """
    class BookView(GenericViewSet):
      # queryset: 设置获取的数据
      queryset = models.BookInfo.objects.all()
      # serializer_class: 设置序列化的类
      serializer_class = BookinfoSeralizer
      # pagination_class : 设置分页的类
      pagination_class = MyPageNumberPagination
      
      def list(self,request,*args,**kwargs):
        
        obj = self.get_queryset() #=> obj = models.BookInfo.objects.all()
        # 获取当前分页的数据
        page_data = self.paginate_queryset(obj) #=>page_obj = MyPageNumberPagination() #获取分页数据page_data = page_obj.paginate_queryset(
        # 获取序列化之后的数据
        ser = self.get_serializer(instance=page_data,many=True) #->ser = BookinfoSeralizer(instance=page_data,many=True)
        
        return Response(ser.data)
    """
    路由会发生变化,配置如下
    """
    url(r"bookpage/$",views.BookView.as_view({'get': 'list'}),name='bookpage')
    """
    
    第三个:ListModelMixin,CreateModelMixin,RetrieveModelMixin,
    DestroyModelMixin,UpdateModelMixin 等视图的使用
    
    """
    from rest_framework.mixins import ListModelMixin,CreateModelMixin,RetrieveModelMixin,DestroyModelMixin,UpdateModelMixin
    from rest_framework.viewsets import GenericViewSet
    # ListModelMixin : 返回列表数据据( get请求)
    # CreateModelMixin : 新增一条数据 (Post请求)
    # RetrieveModelMixin, : 获取详情数据 (get请求)
    # DestroyModelMixin,  : 删除数据的时候 (delete)
    # UpdateModelMixin : 跟新数据的时候使用 (put)
 
    class BookView(ListModelMixin,RetrieveModelMixin,CreateModelMixin,DestroyModelMixin,UpdateModelMixin,GenericViewSet):
      # queryset: 设置获取的数据
      queryset = models.BookInfo.objects.all()
      # serializer_class: 设置序列化的类
      serializer_class = BookinfoSeralizer
      # pagination_class : 设置分页的类
      pagination_class = MyPageNumberPagination
    """
    第四个:ModelViewSet视图的使用
    ModelViewSet继承自istModelMixin,CreateModelMixin,
    RetrieveModelMixin,DestroyModelMixin,UpdateModelMixin视图
    如果要实现最基本的增删改查功能,就直接继承自ModelViewSet
    """
    from rest_framework.viewsets import ModelViewSet
    class BookView(ModelViewSet):
      # queryset: 设置获取的数据
      queryset = models.BookInfo.objects.all()
      # serializer_class: 设置序列化的类
      serializer_class = BookinfoSeralizer
      # pagination_class : 设置分页的类
      pagination_class = MyPageNumberPagination
    """
    视图使用小总结
      只想实现简单的增删改查
        ModelViewSet
      只想增
        CreateModelMixin,GenericViewSet
      只想增删改
        CreateModelMixin,DestroyModelMixin,UpdateModelMixin,GenericViewSet
      如果视图中的业务逻辑复杂,以上都不能满足的时候,直接使用
        APIView
   #自动路由配置
   """
     from django.conf.urls import url,include
     from api import views
     from rest_framework import routers
     
     router = routers.DefaultRouter()
     router.register(r"bookpage",views.BookView,base_name='bookpage')
     
     
     urlpatterns = [
      url(r'v1/',include(router.urls)),
     ]
   """
     
  自动路由会生成四个接口
  ^api/ v1/ ^bookpage/$ [name='bookpage-list']
  ^api/ v1/ ^bookpage\.(?P<format>[a-z0-9]+)/?$ [name='bookpage-list']
  ^api/ v1/ ^bookpage/(?P<pk>[^/.]+)/$ [name='bookpage-detail']
  ^api/ v1/ ^bookpage/(?P<pk>[^/.]+)\.(?P<format>[a-z0-9]+)/?$ [name='bookpage-detail']

频率限制节流

节流:
  自定义节流类
  """
  VISIT_RECORD = {}
  class VisitThrottle(object):
    def __init__(self):
      self.history = None
    def allow_request(self,request,view):
      #实现节流的逻辑
      #基于ip做节流
      # #获取用户访问的IP地址
      # ip_address = request._request.META.get('REMOTE_ADDR')
      ctime = time.time()
      # if ip_address not in VISIT_RECORD:
      #   #第一次访问的时候将访问的时间存储在字典中(ip地址为Key,访问的时间为value值)
      #   VISIT_RECORD[ip_address] = [ctime,]
      #
      # #第二次访问的时候取出访问的历史记录
      # history = VISIT_RECORD[ip_address]
      # 基于用户的节流
      username = request.user.username
      if username not in VISIT_RECORD:
        VISIT_RECORD[username] = [ctime, ]
      history = VISIT_RECORD[username]
      self.history = history
      while history and history[-1] < ctime - 10:
        #如果访问的时间记录超过60秒,就把超过60秒的时间记录移除
        history.pop()
      if len(history) < 6:
        history.insert(0,ctime)
        return True
      return False
    def wait(self):
      #一旦用户访问次数到达阀值,显示用户需要等待的时间
      ctime = time.time()
            #09:54:30  09:54:28
      return 10 - (ctime - self.history[-1])
  """
 
  局部使用
  """
    class OrderView(APIView):
      # throttle_classes设置节流类
      throttle_classes = [VisitThrottle,]
  """
      
  全局设置
  """
  REST_FRAMEWORK = {
    'DEFAULT_THROTTLE_CLASSES':['unitls.throttle.VisitThrottle'],
  }
  """
  
  使用DRF内置的限频类
  """
  from rest_framework.throttling import SimpleRateThrottle
  
  #推荐使用这种
  class VisitThrottle(SimpleRateThrottle):
    #没有登录用户,每分钟访问10次
    scope = 'logined'
    def get_cache_key(self, request, view):
    return request.user.username
  """
 
  全局设置
  """
  REST_FRAMEWORK = {
    'DEFAULT_THROTTLE_RATES':{
      'unlogin':'10/m',
      'logined':'3/m',
    },
    'DEFAULT_THROTTLE_CLASSES':['unitls.throttle.VisitThrottle'],
  }
  """

版本控制

	自定义版本控制类
  """
    class ParmasVersion(object):
      def determine_version(self, request, *args, **kwargs):
        version = request.query_params.get('version')
        return version
  """
 
  使用(局部)
  """
    class VersionView(APIView):
      #设置获取版本的类
      versioning_class = ParmasVersion
  """
 
  全局设置
  """
     'DEFAULT_VERSIONING_CLASS':'unitls.version.ParmasVersion',
  """
 
  使用 DRF内置的版本控制类QueryParameterVersioning(局部)
  """
    from rest_framework.versioning import QueryParameterVersioning
    class VersionView(APIView):
      #设置获取版本的类
      versioning_class = QueryParameterVersioning
  """
  
  设置文件中的配置信息
  """
    REST_FRAMEWORK = {
      'VERSION_PARAM':'version',
      'DEFAULT_VERSION':'v1',
      'ALLOWED_VERSIONS':['v1','v2'],
    }
  """
 
  全局设置
  """
    REST_FRAMEWORK = {
      'VERSION_PARAM':'version',
      'DEFAULT_VERSION':'v1',
      'ALLOWED_VERSIONS':['v1','v2'],
      'DEFAULT_VERSIONING_CLASS':'rest_framework.versioning.QueryParameterVersioning',
    }
  """
 
 
  使用 DRF内置的版本控制类URLPathVersioning(局部)
  """
    from rest_framework.versioning import URLPathVersioning
    class VersionView(APIView):
      #设置获取版本的类
      versioning_class = URLPathVersioning
    """
  
  设置文件中的配置信息
  """
    REST_FRAMEWORK = {
      'VERSION_PARAM':'version',
      'DEFAULT_VERSION':'v1',
      'ALLOWED_VERSIONS':['v1','v2'],
    }
    """
  
  全局设置
  """
    REST_FRAMEWORK = {
      'VERSION_PARAM':'version',
      'DEFAULT_VERSION':'v1',
      'ALLOWED_VERSIONS':['v1','v2'],
      'DEFAULT_VERSIONING_CLASS':'rest_framework.versioning.URLPathVersioning',
    }
  """
 
  如果使用URLPathVersioning,路由格式如下
  """
    url(r"^(?P<version>[v1|v2]+)/version/",VersionView.as_view(),name='vvvv')
  """
 
  #使用 DRF内置的版本控制类URLPathVersioning 反向生成url地址
  """
    #反向生成url地址 reverse
    obj = request.versioning_scheme
    url1 = obj.reverse(viewname='orders',request=request)
    
    #使用django的reverse方法反响生成url地址
    from django.urls import reverse
    url2 = reverse(viewname='orders',kwargs={'version':'v2'})
  """

解析器

因为开发人员post请求上传数据时,传递的数据类型不同,我们可能在request._request.POST中获取不到数据
 
  case1: Content-Type : application/x-www-form-urlencoded
  服务端接收到的post请求的数据格式:username=xxxxx&age=18&sex=男
  我们就可以在request._request.POST中获取到数据
  """
    class UserInfoView(APIView):
      def post(self,request,*args,**kwargs):
        username = request._request.POST.get('username')
        age = request._request.POST.get('age')
        sex = request._request.POST.get('sex')
  """
 
  case2:Content-Type:application/json
  服务端接收到的post请求的数据格式就是json数据:{"username":"xxxx","age":"18","sex":"男"}
  在request._request.POST中就获取不到数据,但是在request.body中可以拿到
  """
    class UserInfoView(APIView):
      def post(self,request,*args,**kwargs):
        import json
        data = json.loads(request.body.decode('utf8'))
        print(data)
  """
 
  DRF内置的解析器FormParser,JSONParser
  使用(局部):
  """
    from rest_framework.parsers import FormParser,JSONParser
    class UserInfoView(APIView):
      parser_classes = [FormParser,JSONParser]
      
      #这时DRF 内部代码会根据request.Content-Type和解析器支持的media_type比较
      从而选择对应的解析器
      
      def post(self,request,*args,**kwargs):
        # 如果使用JSONParser、FormParser解析数据的话
        data = request.data
        print(data)
      
  """

渲染器

 渲染器
  INSTALLED_APPS = [
           'rest_framework',
           ]
  from rest_framework.renderers import BrowsableAPIRenderer,JSONRenderer,AdminRenderer
  class BookView(ModelViewSet):
    # 设置渲染器类型
    renderer_classes = [JSONRenderer]

序列化

 Django的序列化
  """
  #django序例化方式一
  books = models.BookInfo.objects.all().values('id','bookname')
  books = list(books)
  print(type(books), books)
  self.ret['books'] = books
  #django序例化方式二
  books = models.BookInfo.objects.all()
  books = [model_to_dict(item) for item in books]
  self.ret['books'] = books
  """
 
  DRF 序列化
  第一种:继承自serializers.Serializer
  """
     class BookDetailSerializer(serializers.Serializer):
         # 正常的字段序列化
         id = serializers.IntegerField()
         bookname = serializers.CharField()
         author = serializers.CharField()
         category = serializers.IntegerField()
         bookdesc = serializers.CharField()
         
         
         # 获取枚举类型的文本是 source=get_字段名_display
         status = serializers.CharField(
           source='get_status_display'
         )
         categoryname = serializers.CharField(
           source='get_category_display'
         )
         
         # 自定义方法获取字段
         chpaters = serializers.SerializerMethodField()
         #序列化时可以自定义方法获取字段
         def get_chpaters(self,row):
           """ row - > bookinfo """
             chpaters = models.ChpaterInfo.objects.filter(book=row)
             ser = ChpaterSerializer(instance=chpaters,many=True,
                         context=self.context
                         )
             return ser.data
  """
   序列化时生成url
  """
    url = serializers.HyperlinkedIdentityField(
    view_name='chpaterdetail', lookup_field='id',
    lookup_url_kwarg='pk',
    )
  """
  注意:如果序列化类中使用HyperlinkedIdentityField生成url,那我们在序例化时添加context={'request': request}
  """
    ser = BookDetailSerializer(
    instance=obj,many=False,
    context={'request': request}
    )
  """
 
  如果出现关联关系时,获取model对像的某一个字段
  """
    bookname = serializers.CharField(source='book.bookname')
  """
 
  第二种继承自:serializers.ModelSerializer
  """
  class ChpaterDetailSerializer(serializers.ModelSerializer):
    #使用ModelSerializer进行章节详情的序列化
    bookname = serializers.CharField(source='book.bookname')
    class Meta:
      model = models.ChpaterInfo
      #fields = "__all__"
      fields = ['id','bookname']
  """
  
  DRF (序列化时)自定义方法获取数据
  """
    book = serializers.SerializerMethodField()
  """
  """
     def get_book(self,row):
       """ row - > UserInfo"""
         print('======',row.book.all())
         ser = UsersBooksSerializer(
           instance=row.book.all(),
           many=True
         )
      
         return ser.data
  """
  
  DRF depth深度的使用
  # depth会根据关联的数据不停的深入将数据获取出来(最多不超过10层)
  # depth = 1
  """
  class UsersSerializer(serializers.ModelSerializer):
    class Meta:
      model = models.UserInfo
      fields = "__all__"
      #depth会根据关联的数据不停的深入将数据获取出来(最多不超过10层)
      depth = 1
  """
 
  DRF序列化的验证功能
  """
  class UsersSerializer(serializers.ModelSerializer):
    #自定义验证错误的信息
    username = serializers.CharField(error_messages={'required':'用户名不能为空'})
    class Meta:
      model = models.UserInfo
      fields = "__all__"
  """
 
  """
  class UsersView(APIView):
    def post(self,request,*args,**kwargs):
    """DRF 序列化自带验证功能"""
      data = request.data
      #print(data)
      ser = UsersSerializer(data=data)
      if ser.is_valid(): # ser.is_valid()y验证数据的有效性
        print('验证后的数据',ser.validated_data)
        #验证后的数据正确后,保存数据至数据库
        ser.save()
      else:
        #上传数据不符合规范时ser.errors,返回错误详细
        print(ser.errors)
      return Response(data)
  """
 
  自定义字段验证规则
  """
    class UsersInfoSerializer(serializers.ModelSerializer):
    username = serializers.CharField(error_messages={'required':'用户名不能为空'})
      class Meta:
        model = models.UserInfo
        fields = "__all__"
      
      # 用户名中必须包含老王两个字,不包含则认为名字无效
      def validate_username(self,validated_value):
        print(validated_value)
        from rest_framework.exceptions import ValidationError
        if '老王' not in validated_value:
        #验证不通过,抛出异常
          raise ValidationError('用户名不合法')
        #验证通过,返回数据
        return validated_value
  """

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