python - 如何将查询中设置的page_size设置为分页元数据djangorest框架

Question

我已经为我的一个应用程序设置了自定义分页，我面临的问题是 page_size 仅显示应用程序中设置的默认值，但不会根据查询参数中发送的值进行更改。我哪里出错了？

class CustomPagination(PageNumberPagination):
    page_size = 10
    page_size_query_param = 'page_size'

    def get_paginated_response(self, data):
        return Response({"status": True,
                         "data": {
                             'results': data,
                             "meta": {
                                 'page_count':self.page.paginator.num_pages,
                                 'total_results': self.page.paginator.count,
                                 'current_page_no': self.page.number,
                                 'limit': self.page_size,
                                 'last_page': self.page.has_next()
                             }}}, 
                         status=status.HTTP_200_OK)

即使我将查询参数设置为不同的值，page_size 的输出也始终为 10。例如:如果用户在查询参数中设置page_size =2，则应更改为2。

编辑:

View 代码

class ListPCAPIView(ListAPIView):
serializer_class = ListPCSerializer

def get(self, request):
    user = self.request.user
    pc = Pc.objects.filter(
        user_id=user).order_by('pc_name')
    if pc:
        page = self.paginate_queryset(pc)
        if page is not None:
            serializer = self.get_serializer(page, many=True)
            return self.get_paginated_response(serializer.data)
    else:
        raise CustomException(
            detail="pc list is empty.",
            status_code=status.HTTP_400_BAD_REQUEST)

Answer 1

有一种方法可以帮助您实现这一目标。 get_page_size(request) 是的，您需要传入原始请求。幸运的是，您可以通过 self.request

获取它

def get_paginated_response(self, data):
    print(self.get_page_size(self.request))
    ....

此外，获取当前页面大小和记录数所需的总页数可以执行以下操作。

import math
num_of_pages = math.ceil(self.page.paginator.count / self.get_page_size(self.request))

完整示例

分页.py

import math

from dataclasses import dataclass
from dataclasses_json import dataclass_json
from typing import Any
from rest_framework import pagination
from rest_framework.response import Response


@dataclass_json
@dataclass
class PaginationResponse:
    count: int
    next: int
    previous: int
    page_number: int
    num_of_pages: int
    page_size: int
    results: Any


class NumberPagination(pagination.PageNumberPagination):
    page_size_query_param = 'page_size'
    max_page_size = 100

    # Path Query parameter ?page=1&page_size=5
    def get_paginated_response(self, data):
        pagination_response = PaginationResponse(
            count=self.page.paginator.count,
            next=self.page.next_page_number() if self.page.has_next() else None,
            previous=self.page.previous_page_number() if self.page.has_previous() else None,
            page_number=self.page.number,
            num_of_pages=math.ceil(self.page.paginator.count / self.get_page_size(self.request)),
            results=data,
            page_size=self.get_page_size(self.request),
        ).to_dict()

        return Response(pagination_response)

settings.py

REST_FRAMEWORK = {
    'DEFAULT_PAGINATION_CLASS': '<REGISTER-NumberPagination-CLASS-HERE>',
    'PAGE_SIZE': 10,
    ...
}

希望这有帮助