如何在 Django Rest Framework 中使用 LimitOffSetPagination 代替 PageNumberPagination？

Question

我已经使用 Django Rest Framework 用 Python 编写了一段代码，从数据库（MySql）获取数据并使用分页（

LimitOffSetPagination

）在浏览器中查看它。但是它工作不正常。但是当我使用

PageNumberPagination

时它工作正常伟大的。所以我发布了我的新代码。我的代码的注释部分实际上是为了

PageNumberPagination

。所以就忽略它吧。请告诉我需要进行必要的更改并帮助我。出现的错误是：

异常值：index() 缺少 1 个必需的位置参数： ‘请求’

视图.py

from rest_framework.pagination import PageNumberPagination
from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger
from rest_framework.pagination import LimitOffsetPagination


@api_view(['GET','POST'])

def index(self, request):

  if request.method=='GET':

    all_dataobj=fetchdata.objects.all()

    page = self.paginate_queryset(all_dataobj)

     if page is not None:

      pserializer = self.get_fetchdataSerializers(page, many=True)

      return self.get_paginated_response(pserializer.data)

    pserializer = self.get_fetchdataSerializers(all_dataobj, many=True)

    return Response(pserializer.data)

    # paginator = StandardResultsSetPagination()
    # result_page = paginator.paginate_queryset(all_dataobj, request)
    # pserializer=fetchdataSerializers(result_page,many=True)
    # return paginator.get_paginated_response(pserializer.data) 


 elif request.method=='POST':

  serializer=fetchdataSerializers(data=request.data)

  if serializer.is_valid():

    serializer.save()

  return Response(serializer.data,status=status.HTTP_201_CREATED)
  return Response(serializer.errors,status=status.HTTP_400_BAD_REQUEST) 

设置.py

REST_FRAMEWORK = {

      'DEFAULT_PAGINATION_CLASS': 
      'rest_framework.pagination.LimitOffsetPagination',
      'PAGE_SIZE': 10
      }

url.py

urlpatterns = [
path('', m.index, name='index'),
]

我什至发布了我之前用于 PageNumberPagination 的 pagination.py 文件。如果需要进行任何必要的更改，请建议我，或者我应该删除整个文件？？？

分页.py

from rest_framework import pagination

class StandardResultsSetPagination(pagination.PageNumberPagination):
page_size = 10
page_query_param = 'page'
page_size_query_param = 'per_page'
max_page_size = 1000

Answer 1

实际上我自己解决了这个问题...所以想发布解决方案...它可能会对某人有所帮助...所以我发布 view.py、pagination.py 和 settings.py 文件...

视图.py

from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger
from .pagination import CustomPagination


@api_view(['GET','POST'])

def index(request):

  if request.method=='GET':

    all_dataobj=fetchdata.objects.all()

    paginator = CustomPagination()
    result_page = paginator.paginate_queryset(all_dataobj, request)

    pserializer=fetchdataSerializers(result_page,many=True)

    return paginator.get_paginated_response(pserializer.data) 


  elif request.method=='POST':

    serializer=fetchdataSerializers(data=request.data)

    if serializer.is_valid():

      serializer.save()

    return Response(serializer.data,status=status.HTTP_201_CREATED)
    return Response(serializer.errors,status=status.HTTP_400_BAD_REQUEST) 

分页.py

    class CustomPagination(pagination.LimitOffsetPagination):

      default_limit = 1000
      max_limit = 1000000
      min_limit = 1
      min_offset = 0
      max_offset = 1000000

       def paginate_queryset(self, queryset, request, view=None):

         limit = request.query_params.get('limit')
         offset = request.query_params.get('offset')

         if limit:

            limit = int(limit)

            if limit > self.max_limit:

              raise serializers.ValidationError({"limit" : ["Limit should be less 
              than or equal to {0}".format(self.max_limit)]})

            elif limit < self.min_limit:

              raise serializers.ValidationError({"limit" : ["Limit should be greater 
              than or equal to {0}".format(self.min_limit)]})

         if offset:

           offset = int(offset)

           if offset > self.max_offset:

             raise serializers.ValidationError({"offset" : ["Offset should be less 
             than or equal to {0}".format(self.max_offset)]})

          elif offset < self.min_offset:

            raise serializers.ValidationError({"offset" : ["Offset should be greater 
            than or equal to {0}".format(self.min_offset)]})

         return super(self.__class__, self).paginate_queryset(queryset, request, 
         view)

设置.py

REST_FRAMEWORK = {
# 'DEFAULT_PAGINATION_CLASS': 'rest_framework.pagination.PageNumberPagination',
'DEFAULT_PAGINATION_CLASS': 'rest_framework.pagination.LimitOffsetPagination',
'PAGE_SIZE': 100
 }

Answer 2

另一个自定义 limitOffset 分页。我喜欢只将 url 的最后一部分传递给前端。限制和偏移量也可以由客户端控制

from rest_framework.pagination import LimitOffsetPagination
from rest_framework.utils.urls import remove_query_param, replace_query_param


class StandardResultsSetPagination(LimitOffsetPagination):
    default_limit = 6
    limit_query_param = "limit"
    offset_query_param = "offset"
    max_limit = 50



def get_next_link(self):
        if self.offset + self.limit >= self.count:  # type: ignore
           return None
        url = replace_query_param(url="", key=self.limit_query_param, val=self.limit)

        offset = self.offset + self.limit  # type: ignore
        return replace_query_param(url=url, key=self.offset_query_param, val=offset)

def get_previous_link(self):
    if self.offset <= 0:
        return None

    url = replace_query_param(url="", key=self.limit_query_param, val=self.limit)

    if self.offset - self.limit <= 0:  # type: ignore
        return remove_query_param(url=url, key=self.offset_query_param)

    offset = self.offset - self.limit  # type: ignore
    return replace_query_param(url=url, key=self.offset_query_param, val=offset)

响应样本

{
  "code": 2020,
  "msg": "Success",
  "data": {
    "count": 15,
    "next": "?limit=6&offset=6",
    "prev": null,
    "results": []
  }
}