Django rest framework实现分页的示例

框架(架构)  /  管理员 发布于 7年前   194

第一种分页PageNumberPagination

基本使用

（1）urls.py

urlpatterns = [  re_path('(?P<version>[v1|v2]+)/page1/', Pager1View.as_view(),)  #分页1]

（2）api/utils/serializers/pager.py

# api/utils/serializsers/pager.pyfrom rest_framework import serializersfrom api import modelsclass PagerSerialiser(serializers.ModelSerializer):  class Meta:    model = models.Role    fields = "__all__"

（3）views.py

from api.utils.serializsers.pager import PagerSerialiserfrom rest_framework.response import Responsefrom rest_framework.pagination import PageNumberPaginationclass Pager1View(APIView):  def get(self,request,*args,**kwargs):    #获取所有数据    roles = models.Role.objects.all()    #创建分页对象    pg = PageNumberPagination()    #获取分页的数据    page_roles = pg.paginate_queryset(queryset=roles,request=request,view=self)    #对数据进行序列化    ser = PagerSerialiser(instance=page_roles,many=True)    return Response(ser.data)

（4）settings配置

REST_FRAMEWORK = {  #分页  "PAGE_SIZE":2  #每页显示多少个}

自定义分页类

#自定义分页类class MyPageNumberPagination(PageNumberPagination):  #每页显示多少个  page_size = 3  #默认每页显示3个，可以通过传入pager1/?page=2&size=4,改变默认每页显示的个数  page_size_query_param = "size"  #最大页数不超过10  max_page_size = 10  #获取页码数的  page_query_param = "page"class Pager1View(APIView):  def get(self,request,*args,**kwargs):    #获取所有数据    roles = models.Role.objects.all()    #创建分页对象，这里是自定义的MyPageNumberPagination    pg = MyPageNumberPagination()    #获取分页的数据    page_roles = pg.paginate_queryset(queryset=roles,request=request,view=self)    #对数据进行序列化    ser = PagerSerialiser(instance=page_roles,many=True)    return Response(ser.data)

第二种分页 LimitOffsetPagination

自定义

#自定义分页类2class MyLimitOffsetPagination(LimitOffsetPagination):  #默认显示的个数  default_limit = 2  #当前的位置  offset_query_param = "offset"  #通过limit改变默认显示的个数  limit_query_param = "limit"  #一页最多显示的个数  max_limit = 10class Pager1View(APIView):  def get(self,request,*args,**kwargs):    #获取所有数据    roles = models.Role.objects.all()    #创建分页对象    pg = MyLimitOffsetPagination()    #获取分页的数据    page_roles = pg.paginate_queryset(queryset=roles,request=request,view=self)    #对数据进行序列化    ser = PagerSerialiser(instance=page_roles,many=True)    return Response(ser.data)

返回的时候可以用get_paginated_response方法

自带上一页下一页

第三种分页CursorPagination

加密分页方式，只能通过点“上一页”和下一页访问数据

#自定义分页类3 (加密分页)class MyCursorPagination(CursorPagination):  cursor_query_param = "cursor"  page_size = 2   #每页显示2个数据  ordering = 'id'  #排序  page_size_query_param = None  max_page_size = Noneclass Pager1View(APIView):  def get(self,request,*args,**kwargs):    #获取所有数据    roles = models.Role.objects.all()    #创建分页对象    pg = MyCursorPagination()    #获取分页的数据    page_roles = pg.paginate_queryset(queryset=roles,request=request,view=self)    #对数据进行序列化    ser = PagerSerialiser(instance=page_roles,many=True)    # return Response(ser.data)    return pg.get_paginated_response(ser.data)

代码

版本、解析器、序列化和分页

# MyProject2/urls.pyfrom django.contrib import adminfrom django.urls import path,includeurlpatterns = [  #path('admin/', admin.site.urls),  path('api/',include('api.urls') ),]

# api/urls.pyfrom django.urls import path,re_pathfrom .views import UserView,PaserView,RolesView,UserInfoView,GroupView,UserGroupViewfrom .views import Pager1Viewurlpatterns = [  re_path('(?P<version>[v1|v2]+)/users/', UserView.as_view(),name = 'api_user'), #版本  path('paser/', PaserView.as_view(),),  #解析  re_path('(?P<version>[v1|v2]+)/roles/', RolesView.as_view()),   #序列化  re_path('(?P<version>[v1|v2]+)/info/', UserInfoView.as_view()),  #序列化  re_path('(?P<version>[v1|v2]+)/group/(?P<pk>\d+)/', GroupView.as_view(),name = 'gp'),  #序列化生成url  re_path('(?P<version>[v1|v2]+)/usergroup/', UserGroupView.as_view(),),  #序列化做验证  re_path('(?P<version>[v1|v2]+)/pager1/', Pager1View.as_view(),)  #分页1]

# api/models.pyfrom django.db import modelsclass UserInfo(models.Model):  USER_TYPE = (    (1,'普通用户'),    (2,'VIP'),    (3,'SVIP')  )  user_type = models.IntegerField(choices=USER_TYPE)  username = models.CharField(max_length=32,unique=True)  password = models.CharField(max_length=64)  group = models.ForeignKey('UserGroup',on_delete=models.CASCADE)  roles = models.ManyToManyField('Role')class UserToken(models.Model):  user = models.OneToOneField('UserInfo',on_delete=models.CASCADE)  token = models.CharField(max_length=64)class UserGroup(models.Model):  title = models.CharField(max_length=32)class Role(models.Model):  title = models.CharField(max_length=32)

# api/views.pyimport jsonfrom django.shortcuts import render,HttpResponsefrom rest_framework.views import APIViewfrom rest_framework.request import Requestfrom rest_framework.versioning import URLPathVersioningfrom . import models##########################################版本和解析器#####################################################class UserView(APIView):  def get(self,request,*args,**kwargs):    #获取版本    print(request.version)    #获取处理版本的对象    print(request.versioning_scheme)    #获取浏览器访问的url，reverse反向解析    #需要两个参数：viewname就是url中的别名，request=request是url中要传入的参数    #(?P<version>[v1|v2]+)/users/，这里本来需要传version的参数，但是version包含在request里面，所有只需要request=request就可以    url_path = request.versioning_scheme.reverse(viewname='api_user',request=request)    print(url_path)    self.dispatch    return HttpResponse('用户列表')# from rest_framework.parsers import JSONParser,FormParserclass PaserView(APIView):  '''解析'''  # parser_classes = [JSONParser,FormParser,]  #JSONParser：表示只能解析content-type:application/json的头  #FormParser:表示只能解析content-type:application/x-www-form-urlencoded的头  def post(self,request,*args,**kwargs):    #获取解析后的结果    print(request.data)    return HttpResponse('paser')###########################################序列化###########################################################from rest_framework import serializers#要先写一个序列化的类class RolesSerializer(serializers.Serializer):  #Role表里面的字段id和title序列化  id = serializers.IntegerField()  title = serializers.CharField()class RolesView(APIView):  def get(self,request,*args,**kwargs):    # 方式一：对于[obj,obj,obj]    # （Queryset）    # roles = models.Role.objects.all()    # 序列化，两个参数，instance:Queryset 如果有多个值，就需要加 mangy=True    # ser = RolesSerializer(instance=roles,many=True)    # 转成json格式，ensure_ascii=False表示显示中文，默认为True    # ret = json.dumps(ser.data,ensure_ascii=False)    # 方式二：    role = models.Role.objects.all().first()    ser = RolesSerializer(instance=role, many=False)    ret = json.dumps(ser.data, ensure_ascii=False)    return HttpResponse(ret)# class UserInfoSerializer(serializers.Serializer):#   '''序列化用户的信息'''#   #user_type是choices（1,2,3），显示全称的方法用source#   type = serializers.CharField(source="get_user_type_display")#   username = serializers.CharField()#   password = serializers.CharField()#   #group.title：组的名字#   group = serializers.CharField(source="group.title")#   #SerializerMethodField(),表示自定义显示#   #然后写一个自定义的方法#   rls = serializers.SerializerMethodField()##   def get_rls(self,row):#     #获取用户所有的角色#     role_obj_list = row.roles.all()#     ret = []#     #获取角色的id和名字#     #以字典的键值对方式显示#     for item in role_obj_list:#       ret.append({"id":item.id,"title":item.title})#     return ret# class UserInfoSerializer(serializers.ModelSerializer):#   type = serializers.CharField(source="get_user_type_display")#   group = serializers.CharField(source="group.title")#   rls = serializers.SerializerMethodField()##   def get_rls(self, row):#     # 获取用户所有的角色#     role_obj_list = row.roles.all()#     ret = []#     # 获取角色的id和名字#     # 以字典的键值对方式显示#     for item in role_obj_list:#       ret.append({"id": item.id, "title": item.title})#     return ret##   class Meta:#     model = models.UserInfo#     fields = ['id','username','password','type','group','rls']# class UserInfoSerializer(serializers.ModelSerializer):#   class Meta:#     model = models.UserInfo#     #fields = "__all__"#     fields = ['id','username','password','group','roles']#     #表示连表的深度#     depth = 1class UserInfoSerializer(serializers.ModelSerializer):  group = serializers.HyperlinkedIdentityField(view_name='gp',lookup_field='group_id',lookup_url_kwarg='pk')  class Meta:    model = models.UserInfo    #fields = "__all__"    fields = ['id','username','password','group','roles']    #表示连表的深度    depth = 0class UserInfoView(APIView):  '''用户的信息'''  def get(self,request,*args,**kwargs):    users = models.UserInfo.objects.all()    #这里必须要传参数context={'request':request}    ser = UserInfoSerializer(instance=users,many=True,context={'request':request})    ret = json.dumps(ser.data,ensure_ascii=False)    return HttpResponse(ret)class GroupSerializer(serializers.ModelSerializer):  class Meta:    model = models.UserGroup    fields = "__all__"class GroupView(APIView):  def get(self,request,*args,**kwargs):    pk = kwargs.get('pk')    obj = models.UserGroup.objects.filter(pk=pk).first()    ser = GroupSerializer(instance=obj,many=False)    ret = json.dumps(ser.data,ensure_ascii=False)    return HttpResponse(ret)####################################序列化之用户请求数据验证验证#####################################自定义验证规则class GroupValidation(object):  def __init__(self,base):    self.base = base  def __call__(self, value):    if not value.startswith(self.base):      message = "标题必须以%s为开头"%self.base      raise serializers.ValidationError(message)class UserGroupSerializer(serializers.Serializer):  title = serializers.CharField(validators=[GroupValidation('以我开头'),])class UserGroupView(APIView):  def post(self,request,*args, **kwargs):    ser = UserGroupSerializer(data=request.data)    if ser.is_valid():      print(ser.validated_data['title'])    else:      print(ser.errors)    return HttpResponse("用户提交数据验证")##################################################分页###################################################from api.utils.serializsers.pager import PagerSerialiserfrom rest_framework.response import Responsefrom rest_framework.pagination import PageNumberPagination,LimitOffsetPagination,CursorPagination# #自定义分页类1# class MyPageNumberPagination(PageNumberPagination):#   #每页显示多少个#   page_size = 3#   #默认每页显示3个，可以通过传入pager1/?page=2&size=4,改变默认每页显示的个数#   page_size_query_param = "size"#   #最大页数不超过10#   max_page_size = 10#   #获取页码数的#   page_query_param = "page"#自定义分页类2class MyLimitOffsetPagination(LimitOffsetPagination):  #默认显示的个数  default_limit = 2  #当前的位置  offset_query_param = "offset"  #通过limit改变默认显示的个数  limit_query_param = "limit"  #一页最多显示的个数  max_limit = 10#自定义分页类3 (加密分页)class MyCursorPagination(CursorPagination):  cursor_query_param = "cursor"  page_size = 2   #每页显示2个数据  ordering = 'id'  #排序  page_size_query_param = None  max_page_size = Noneclass Pager1View(APIView):  def get(self,request,*args,**kwargs):    #获取所有数据    roles = models.Role.objects.all()    #创建分页对象    pg = MyCursorPagination()    #获取分页的数据    page_roles = pg.paginate_queryset(queryset=roles,request=request,view=self)    #对数据进行序列化    ser = PagerSerialiser(instance=page_roles,many=True)    return Response(ser.data)    # return pg.get_paginated_response(ser.data)

# api/utils/serializsers/pager.pyfrom rest_framework import serializersfrom api import modelsclass PagerSerialiser(serializers.ModelSerializer):  class Meta:    model = models.Role    fields = "__all__"

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