27、DRF_查询、排序、分页的代码合辑和使用示例

作者: 猪儿打滚 | 来源:发表于2020-07-17 14:09 被阅读0次

1.安装
pip install django-filter
2.settings.py添加配置（全局配置分页、查询、排序引擎）

INSTALLED_APPS = ['django_filters',]
REST_FRAMEWORK = {
    'DEFAULT_FILTER_BACKENDS': (
        'django_filters.rest_framework.DjangoFilterBackend',
        'rest_framework.filters.OrderingFilter'
    ),

    # 设置分页引擎
    'rest_framework.pagination.PageNumberPagination'
    # 指定每页返回的条数
    'PAGE_SIZE': 5

}

3.urils/pagination.py重写分页类

from rest_framework.pagination import PageNumberPagination

class MyPageNumberPagination(PageNumberPagination):
   # 当前页数的key从page修改为p
    page_query_param = 'p'
    # 默认每页显示的条数为2
    page_size = 2
    # 把page_size修改为s
    page_size_query_param = 's'
    # 分页的最大的page_size，每页不能显示超过100条
    max_page_size = 100

4.projects/views.py

from django.http import JsonResponse
from rest_framework.viewsets import ModelViewSet
from rest_framework.generics import GenericAPIView
from rest_framework.response import Response
from django_filters.rest_framework import DjangoFilterBackend
from rest_framework.filters import OrderingFilter

from projects.serializer import ProjectSerializer
from .models import Projects
from utils.pagination import MyPageNumberPagination


class ProjectsList(GenericAPIView):
    """
    不带参数的请求
    """
    # 指定想要的引擎
    filter_backends = [DjangoFilterBackend, OrderingFilter]
    # 设置过滤字段  （查询字段）
    filterset_fields  = ['name']
    # 设置排序字段
    ordering_fields = ['id', 'create_time']
    # 定义分页类
    pagination_class = MyPageNumberPagination
  
    # 获取queryset
    queryset = Projects.objects.all()
    serializer_class = ProjectSerializer

    def get(self, request):
        """
        获取所有接口信息
        :param request:
        :return:
        """
        # 调用get_queryset方法来获取查询集
        query = self.get_queryset()
        # 对查询集进行过滤(使用的是上面类属性定义的过滤引擎)，并覆盖，获取到的是经过排序后的查询集
        qs = self.filter_queryset(query)
        # 使用paginate_queryset进行分页，返回的是分页后的查询集（如果没有指定分页引擎，那么返回的是None）
        page = self.paginate_queryset(qs)
  
        ## 判断是否指定了分页引擎，指定了则返回分页后的数据，否则返回只经过过滤引擎处理后的数据
        if page is not None:
            serializer_obj = self.get_serializer(instance=page, many=True)
            ## 返回分页后的数据
            return self.get_paginated_response(serializer_obj.data)

        # 建议使用get_serializer方法来获取序列化器
        serializer_obj = self.get_serializer(instance=qs, many=True)
        # 响应返回；如果请求没有指定Accept，那么默认返回json
        return Response(serializer_obj.data, status=200)

项目/urls.py

from django.contrib import admin
from django.urls import path, include

urlpatterns = [
    # path('admin/', admin.site.urls),
    path('', include('projects.urls')),
    path('api/', include('rest_framework.urls'))
]

projects/urls.py

from django.urls import path
from rest_framework.routers import DefaultRouter

from projects import views


urlpatterns = [
    path('project/', views.ProjectsList.as_view()),
    path('project/<int:pk>/', views.ProjectsDetail.as_view()),
]

router = DefaultRouter()
router.register('project', views.ProjectsViewSet)

urlpatterns += router.urls