一、在權限表裏新建一個自關聯的字段pid

rbac/models.py

class Permission(models.Model):
    """
    權限表
    """
    title = models.CharField(verbose_name=‘標題‘, max_length=32)
    url = models.CharField(verbose_name=‘含正則的URL‘, max_length=128)

    menu = models.ForeignKey(verbose_name=‘所屬菜單‘, to=Menu, null=True, blank=True,
                             help_text
 
=‘null表示不是菜單，非null表示是二級菜單‘, on_delete=models.CASCADE
                             )

    pid = models.ForeignKey(verbose_name=‘關聯的權限‘, to=‘Permission‘, null=True, blank=True, related_name=‘parents‘,
                            help_text=‘對於非菜單權限需要選擇一個可以成為菜單的權限，用於做默認展開和選中菜單‘,
                            on_delete
 
=models.CASCADE
                            )

    def __str__(self):
        return self.title

說明：拿客戶列表來舉例:

沒有pid，有menu_id的是二級菜單，有pid，沒有menu_id的是具體的權限，是不可以做菜單的。我們的目的是讓用戶點擊增加、編輯、刪除客戶的時候，客戶列表被默認選中

二、初始化權限中增加權限id和其父id（也就是pid、二級菜單）

rbac/service/init_permission.py

from permission_learn import settings


def init_permission(current_user, request):
    """
    用戶權限的初始化
    :param current_user:  當前登錄用戶
    :param request:
    :return:
    """

    permission_menu_queryset = current_user.roles.filter(permissions__isnull=False).values(
        ‘permissions__id‘,
        ‘permissions__title‘,
        ‘permissions__url‘,
        ‘permissions__pid_id‘,
        ‘permissions__menu_id‘,
        ‘permissions__menu__title‘,
        ‘permissions__menu__icon‘,
    )

    menu_dict = {}
    permission_list = []

    for item in permission_menu_queryset:
        permission_list.append(
            {‘id‘: item[‘permissions__id‘], ‘url‘: item[‘permissions__url‘], ‘pid‘: item[‘permissions__pid_id‘]}
        )

        menu_id = item[‘permissions__menu_id‘]

        if not menu_id:
            continue

        # 二級菜單沒有pid
        second_menu = {‘id‘:item[‘permissions__id‘],‘title‘: item[‘permissions__title‘], ‘url‘: item[‘permissions__url‘]}

        if menu_id in menu_dict:
            menu_dict[menu_id][‘second_menu‘].append(second_menu)
        else:
            menu_dict[menu_id] = {
                ‘title‘: item[‘permissions__menu__title‘],
                ‘icon‘: item[‘permissions__menu__icon‘],
                ‘second_menu‘: [second_menu, ]
            }

        request.session[settings.PERMISSION_SESSION_KEY] = permission_list
        request.session[settings.MENU_SESSION_KEY] = menu_dict

初始化權限的時候，給具體權限增加了id和它的pid，給二級菜單增加了id，是為了當用戶點擊具體權限的時候，可以拿到這個權限的pid，然後和二級菜單的id做比較，如果一樣就給二級菜單的id加上選中的樣式。

三、中間件獲取到當前點擊的權限的二級菜單的id

rbac/middlewares/rbac.py

import re

from django.utils.deprecation import MiddlewareMixin
from django.shortcuts import HttpResponse
from permission_learn import settings


class RbacMiddleware(MiddlewareMixin):
    def process_request(self, request):
        white_list = settings.WHITE_LIST
        current_path = request.path_info

        for valid_url in white_list:
            if re.match(valid_url, current_path):
                return None

        permission_list = request.session.get(settings.PERMISSION_SESSION_KEY)

        if not permission_list:
            return HttpResponse(‘請先登錄‘)

        has_permission = False

        for item in permission_list:
            reg = ‘^%s$‘ % item[‘url‘]
            if re.match(reg, current_path):
                has_permission = True

                # 如果是二級菜單(/customer/list/)，沒有pid，采用id，就是二級菜單的id，如果是具體權限(/customer/add/)，就會采用pid，也是二級菜單的id
                request.current_selected_permission = item[‘pid‘] or item[‘id‘]  # 前面為True就用前面的，前面為False就用後面的
                break

        if not has_permission:
            return HttpResponse(‘未獲取權限，請先獲取權限‘)

四、在templatestag給用戶選中的權限的二級菜單加樣式

rbac/templatestag/rbac.py

import re
from collections import OrderedDict

from django.conf import settings
from django.template import Library

register = Library()

@register.inclusion_tag(‘rbac/multi_menu.html‘)
def multi_menu(request):
    menu_dict = request.session[settings.MENU_SESSION_KEY]


    key_list = sorted(menu_dict)

    ordered_dict = OrderedDict()
    for key in key_list:
        menu = menu_dict[key]
        menu[‘class‘] = ‘hide‘

        for second_menu in menu[‘second_menu‘]:
            # second_menu[‘id‘]是二級菜單的id，current_selected_permission是當前所選權限的二級菜單的id
            if second_menu[‘id‘] == request.current_selected_permission:
                second_menu[‘class‘] = ‘active‘
                menu[‘class‘] = ‘‘

        ordered_dict[key] = menu

    context = {
        ‘menus‘: ordered_dict,
    }

    return context

權限組件（3）：非菜單默認選中