• rest-framework框架的基本组件


    知识预

     

    快速实例

     

    序列化

    创建一个序列化类

    简单使用

    开发我们的Web API的第一件事是为我们的Web API提供一种将代码片段实例序列化和反序列化为诸如json之类的表示形式的方式。我们可以通过声明与Django forms非常相似的序列化器(serializers)来实现。

    models部分:

    复制代码
    from django.db import models
    
    # Create your models here.
    
    
    class Book(models.Model):
        title=models.CharField(max_length=32)
        price=models.IntegerField()
        pub_date=models.DateField()
        publish=models.ForeignKey("Publish")
        authors=models.ManyToManyField("Author")
        def __str__(self):
            return self.title
    
    class Publish(models.Model):
        name=models.CharField(max_length=32)
        email=models.EmailField()
        def __str__(self):
            return self.name
    
    class Author(models.Model):
        name=models.CharField(max_length=32)
        age=models.IntegerField()
        def __str__(self):
            return self.name
    复制代码

    views部分:

    复制代码
    from rest_framework.views import APIView
    from rest_framework.response import Response
    from .models import *
    from django.shortcuts import HttpResponse
    from django.core import serializers
    
    
    from rest_framework import serializers
    
    class BookSerializers(serializers.Serializer):
        title=serializers.CharField(max_length=32)
        price=serializers.IntegerField()
        pub_date=serializers.DateField()
        publish=serializers.CharField(source="publish.name")
        #authors=serializers.CharField(source="authors.all")
        authors=serializers.SerializerMethodField()
        def get_authors(self,obj):
            temp=[]
            for author in obj.authors.all():
                temp.append(author.name)
            return temp
    
    
    class BookViewSet(APIView):
    
        def get(self,request,*args,**kwargs):
            book_list=Book.objects.all()
            # 序列化方式1:
            # from django.forms.models import model_to_dict
            # import json
            # data=[]
            # for obj in book_list:
            #     data.append(model_to_dict(obj))
            # print(data)
            # return HttpResponse("ok")
    
            # 序列化方式2:
            # data=serializers.serialize("json",book_list)
            # return HttpResponse(data)
    
            # 序列化方式3:
            bs=BookSerializers(book_list,many=True)
            return Response(bs.data)
    复制代码

    ModelSerializer

    class BookSerializers(serializers.ModelSerializer):
          class Meta:
              model=Book
              fields="__all__"
              depth=1

    提交post请求

    复制代码
      def post(self,request,*args,**kwargs):
           
            bs=BookSerializers(data=request.data,many=False)
            if bs.is_valid():
                # print(bs.validated_data)
                bs.save()
                return Response(bs.data)
            else:
                return HttpResponse(bs.errors)
    复制代码

    重写save中的create方法

    复制代码
    class BookSerializers(serializers.ModelSerializer):
    
          class Meta:
              model=Book
              fields="__all__"
              # exclude = ['authors',]
              # depth=1
    
          def create(self, validated_data):
            
              authors = validated_data.pop('authors')
              obj = Book.objects.create(**validated_data)
              obj.authors.add(*authors)
              return obj
    复制代码

     单条数据的get和put请求

    复制代码
    class BookDetailViewSet(APIView):
    
        def get(self,request,pk):
            book_obj=Book.objects.filter(pk=pk).first()
            bs=BookSerializers(book_obj)
            return Response(bs.data)
    
        def put(self,request,pk):
            book_obj=Book.objects.filter(pk=pk).first()
            bs=BookSerializers(book_obj,data=request.data)
            if bs.is_valid():
                bs.save()
                return Response(bs.data)
            else:
                return HttpResponse(bs.errors)
    复制代码

    超链接API:Hyperlinked

    复制代码
    class BookSerializers(serializers.ModelSerializer):
          publish= serializers.HyperlinkedIdentityField(
    view_name='publish_detail',
    lookup_field="publish_id",
    lookup_url_kwarg="pk") class Meta: model=Book fields="__all__" #depth=1
    复制代码

    urls部分:

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    urlpatterns = [
        url(r'^books/$', views.BookViewSet.as_view(),name="book_list"),
        url(r'^books/(?P<pk>d+)$', views.BookDetailViewSet.as_view(),name="book_detail"),
        url(r'^publishers/$', views.PublishViewSet.as_view(),name="publish_list"),
        url(r'^publishers/(?P<pk>d+)$', views.PublishDetailViewSet.as_view(),name="publish_detail"),
    ]
    回到顶部

    视图三部曲

    使用混合(mixins)

    上一节的视图部分:

    复制代码
    from rest_framework.views import APIView
    from rest_framework.response import Response
    from .models import *
    from django.shortcuts import HttpResponse
    from django.core import serializers
    
    
    from rest_framework import serializers
    
    
    class BookSerializers(serializers.ModelSerializer):
          class Meta:
              model=Book
              fields="__all__"
              #depth=1
    
    
    class PublshSerializers(serializers.ModelSerializer):
    
          class Meta:
              model=Publish
              fields="__all__"
              depth=1
    
    
    class BookViewSet(APIView):
    
        def get(self,request,*args,**kwargs):
            book_list=Book.objects.all()
            bs=BookSerializers(book_list,many=True,context={'request': request})
            return Response(bs.data)
    
    
        def post(self,request,*args,**kwargs):
            print(request.data)
            bs=BookSerializers(data=request.data,many=False)
            if bs.is_valid():
                print(bs.validated_data)
                bs.save()
                return Response(bs.data)
            else:
                return HttpResponse(bs.errors)
    
    
    class BookDetailViewSet(APIView):
    
        def get(self,request,pk):
            book_obj=Book.objects.filter(pk=pk).first()
            bs=BookSerializers(book_obj,context={'request': request})
            return Response(bs.data)
    
        def put(self,request,pk):
            book_obj=Book.objects.filter(pk=pk).first()
            bs=BookSerializers(book_obj,data=request.data,context={'request': request})
            if bs.is_valid():
                bs.save()
                return Response(bs.data)
            else:
                return HttpResponse(bs.errors)
    
    
    class PublishViewSet(APIView):
    
        def get(self,request,*args,**kwargs):
            publish_list=Publish.objects.all()
            bs=PublshSerializers(publish_list,many=True,context={'request': request})
            return Response(bs.data)
    
    
        def post(self,request,*args,**kwargs):
    
            bs=PublshSerializers(data=request.data,many=False)
            if bs.is_valid():
                # print(bs.validated_data)
                bs.save()
                return Response(bs.data)
            else:
                return HttpResponse(bs.errors)
    
    
    class PublishDetailViewSet(APIView):
    
        def get(self,request,pk):
    
            publish_obj=Publish.objects.filter(pk=pk).first()
            bs=PublshSerializers(publish_obj,context={'request': request})
            return Response(bs.data)
    
        def put(self,request,pk):
            publish_obj=Publish.objects.filter(pk=pk).first()
            bs=PublshSerializers(publish_obj,data=request.data,context={'request': request})
            if bs.is_valid():
                bs.save()
                return Response(bs.data)
            else:
                return HttpResponse(bs.errors)
    复制代码

    mixin类编写视图

    复制代码
    from rest_framework import mixins
    from rest_framework import generics
    
    class BookViewSet(mixins.ListModelMixin,
                      mixins.CreateModelMixin,
                      generics.GenericAPIView):
    
        queryset = Book.objects.all()
        serializer_class = BookSerializers
    
        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 BookDetailViewSet(mixins.RetrieveModelMixin,
                        mixins.UpdateModelMixin,
                        mixins.DestroyModelMixin,
                        generics.GenericAPIView):
        queryset = Book.objects.all()
        serializer_class = BookSerializers
    
        def get(self, request, *args, **kwargs):
            return self.retrieve(request, *args, **kwargs)
    
        def put(self, request, *args, **kwargs):
            return self.update(request, *args, **kwargs)
    
        def delete(self, request, *args, **kwargs):
            return self.destroy(request, *args, **kwargs)
    复制代码

    使用通用的基于类的视图

    通过使用mixin类,我们使用更少的代码重写了这些视图,但我们还可以再进一步。REST框架提供了一组已经混合好(mixed-in)的通用视图,我们可以使用它来简化我们的views.py模块。

    复制代码
    from rest_framework import mixins
    from rest_framework import generics
    
    class BookViewSet(generics.ListCreateAPIView):
    
        queryset = Book.objects.all()
        serializer_class = BookSerializers
    
    class BookDetailViewSet(generics.RetrieveUpdateDestroyAPIView):
        queryset = Book.objects.all()
        serializer_class = BookSerializers
    
    class PublishViewSet(generics.ListCreateAPIView):
    
        queryset = Publish.objects.all()
        serializer_class = PublshSerializers
    
    class PublishDetailViewSet(generics.RetrieveUpdateDestroyAPIView):
        queryset = Publish.objects.all()
        serializer_class = PublshSerializers
    复制代码

    viewsets.ModelViewSet

    urls.py:

    复制代码
        url(r'^books/$', views.BookViewSet.as_view({"get":"list","post":"create"}),name="book_list"),
        url(r'^books/(?P<pk>d+)$', views.BookViewSet.as_view({
                    'get': 'retrieve',
                    'put': 'update',
                    'patch': 'partial_update',
                    'delete': 'destroy'
                }),name="book_detail"),
    复制代码

    views.py:

    class BookViewSet(viewsets.ModelViewSet):
        queryset = Book.objects.all()
        serializer_class = BookSerializers

    认证与权限组件

    认证组件

    局部视图认证

    在app01.service.auth.py:

    复制代码
    class Authentication(BaseAuthentication):
    
        def authenticate(self,request):
            token=request._request.GET.get("token")
            token_obj=UserToken.objects.filter(token=token).first()
            if not token_obj:
                raise exceptions.AuthenticationFailed("验证失败!")
            return (token_obj.user,token_obj)
    复制代码

    在views.py:

    复制代码
    def get_random_str(user):
        import hashlib,time
        ctime=str(time.time())
    
        md5=hashlib.md5(bytes(user,encoding="utf8"))
        md5.update(bytes(ctime,encoding="utf8"))
    
        return md5.hexdigest()
    
    
    from app01.service.auth import *
    
    from django.http import JsonResponse
    class LoginViewSet(APIView):
        authentication_classes = [Authentication,]
        def post(self,request,*args,**kwargs):
            res={"code":1000,"msg":None}
            try:
                user=request._request.POST.get("user")
                pwd=request._request.POST.get("pwd")
                user_obj=UserInfo.objects.filter(user=user,pwd=pwd).first()
                print(user,pwd,user_obj)
                if not user_obj:
                    res["code"]=1001
                    res["msg"]="用户名或者密码错误"
                else:
                    token=get_random_str(user)
                    UserToken.objects.update_or_create(user=user_obj,defaults={"token":token})
                    res["token"]=token
    
            except Exception as e:
                res["code"]=1002
                res["msg"]=e
    
            return JsonResponse(res,json_dumps_params={"ensure_ascii":False})
    复制代码

    全局视图认证组件

    settings.py配置如下:

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    REST_FRAMEWORK={
        "DEFAULT_AUTHENTICATION_CLASSES":["app01.service.auth.Authentication",]
    }

    权限组件

    局部视图权限

    在app01.service.permissions.py中:

    复制代码
    from rest_framework.permissions import BasePermission
    class SVIPPermission(BasePermission):
        message="SVIP才能访问!"
        def has_permission(self, request, view):
            if request.user.user_type==3:
                return True
            return False
    复制代码

    在views.py:

    from app01.service.permissions import *
    
    class BookViewSet(generics.ListCreateAPIView):
        permission_classes = [SVIPPermission,]
        queryset = Book.objects.all()
        serializer_class = BookSerializers

    全局视图权限

    settings.py配置如下:

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    REST_FRAMEWORK={
        "DEFAULT_AUTHENTICATION_CLASSES":["app01.service.auth.Authentication",],
        "DEFAULT_PERMISSION_CLASSES":["app01.service.permissions.SVIPPermission",]
    }

    throttle(访问频率)组件

    局部视图throttle

    在app01.service.throttles.py中:

    复制代码
    from rest_framework.throttling import BaseThrottle
    
    VISIT_RECORD={}
    class VisitThrottle(BaseThrottle):
    
        def __init__(self):
            self.history=None
    
        def allow_request(self,request,view):
            remote_addr = request.META.get('REMOTE_ADDR')
            print(remote_addr)
            import time
            ctime=time.time()
    
            if remote_addr not in VISIT_RECORD:
                VISIT_RECORD[remote_addr]=[ctime,]
                return True
    
            history=VISIT_RECORD.get(remote_addr)
            self.history=history
    
            while history and history[-1]<ctime-60:
                history.pop()
    
            if len(history)<3:
                history.insert(0,ctime)
                return True
            else:
                return False
    
        def wait(self):
            import time
            ctime=time.time()
            return 60-(ctime-self.history[-1])
    复制代码

    在views.py中:

    from app01.service.throttles import *
    
    class BookViewSet(generics.ListCreateAPIView):
        throttle_classes = [VisitThrottle,]
        queryset = Book.objects.all()
        serializer_class = BookSerializers

    全局视图throttle

    REST_FRAMEWORK={
        "DEFAULT_AUTHENTICATION_CLASSES":["app01.service.auth.Authentication",],
        "DEFAULT_PERMISSION_CLASSES":["app01.service.permissions.SVIPPermission",],
        "DEFAULT_THROTTLE_CLASSES":["app01.service.throttles.VisitThrottle",]
    }

    内置throttle类

    在app01.service.throttles.py修改为:

    class VisitThrottle(SimpleRateThrottle):
    
        scope="visit_rate"
        def get_cache_key(self, request, view):
    
            return self.get_ident(request)

    settings.py设置:

    复制代码
    REST_FRAMEWORK={
        "DEFAULT_AUTHENTICATION_CLASSES":["app01.service.auth.Authentication",],
        "DEFAULT_PERMISSION_CLASSES":["app01.service.permissions.SVIPPermission",],
        "DEFAULT_THROTTLE_CLASSES":["app01.service.throttles.VisitThrottle",],
        "DEFAULT_THROTTLE_RATES":{
            "visit_rate":"5/m",
        }
    }
    复制代码
     

    解析器

    request类

    django的request类和rest-framework的request类的源码解析

    局部视图

    复制代码
    from rest_framework.parsers import JSONParser,FormParser
    class PublishViewSet(generics.ListCreateAPIView):
        parser_classes = [FormParser,JSONParser]
        queryset = Publish.objects.all()
        serializer_class = PublshSerializers
        def post(self, request, *args, **kwargs):
            print("request.data",request.data)
            return self.create(request, *args, **kwargs)
    复制代码

    全局视图

    复制代码
    REST_FRAMEWORK={
        "DEFAULT_AUTHENTICATION_CLASSES":["app01.service.auth.Authentication",],
        "DEFAULT_PERMISSION_CLASSES":["app01.service.permissions.SVIPPermission",],
        "DEFAULT_THROTTLE_CLASSES":["app01.service.throttles.VisitThrottle",],
        "DEFAULT_THROTTLE_RATES":{
            "visit_rate":"5/m",
        },
        "DEFAULT_PARSER_CLASSES":['rest_framework.parsers.FormParser',]
    }
    复制代码

    分页

    简单分页

    复制代码
    from rest_framework.pagination import PageNumberPagination,LimitOffsetPagination
    
    class PNPagination(PageNumberPagination):
            page_size = 1
            page_query_param = 'page'
            page_size_query_param = "size"
            max_page_size = 5
    
    class BookViewSet(viewsets.ModelViewSet):
    
        queryset = Book.objects.all()
        serializer_class = BookSerializers
        def list(self,request,*args,**kwargs):
    
            book_list=Book.objects.all()
            pp=LimitOffsetPagination()
            pager_books=pp.paginate_queryset(queryset=book_list,request=request,view=self)
            print(pager_books)
            bs=BookSerializers(pager_books,many=True)
    
            #return Response(bs.data)
            return pp.get_paginated_response(bs.data)
    复制代码

    偏移分页

    from rest_framework.pagination import LimitOffsetPagination
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  • 原文地址:https://www.cnblogs.com/xiaozhican/p/9360478.html
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