Django基于RBAC的权限组件实战：从模型设计到中间件拦截

#　models.py

from django.db import models


class Menu(models.Model):
  '''页面中的菜单名'''
  title = models.CharField(max_length=32)

class Group(models.Model):
  '''权限url所属的组'''
  caption = models.CharField(verbose_name='组名称',max_length=32)
  menu =models.ForeignKey(verbose_name='组所属菜单',to='Menu',default=1) # 组所在的菜单

  class Meta:
    verbose_name_plural = 'Group组表'

  def __str__(self):
    return self.caption

class User(models.Model):
  """
  用户表
  """
  username = models.CharField(verbose_name='用户名',max_length=32)
  password = models.CharField(verbose_name='密码',max_length=64)
  email = models.CharField(verbose_name='邮箱',max_length=32)

  roles = models.ManyToManyField(verbose_name='具有的所有角色',to="Role",blank=True)
  class Meta:
    verbose_name_plural = "用户表"

  def __str__(self):
    return self.username

class Role(models.Model):
  """
  角色表
  """
  title = models.CharField(max_length=32)
  permissions = models.ManyToManyField(verbose_name='具有的所有权限',to='Permission',blank=True)
  class Meta:
    verbose_name_plural = "角色表"

  def __str__(self):
    return self.title


class Permission(models.Model):
  """
  权限表
  """
  title = models.CharField(verbose_name='标题',max_length=32)
  url = models.CharField(verbose_name="含正则URL",max_length=64)
  is_menu = models.BooleanField(verbose_name="是否是菜单")

  code = models.CharField(verbose_name='url代码',max_length=32,default=0) # 路径对应的描述名称
  group = models.ForeignKey(verbose_name='所属组',to='Group',null=True,blank=True)  # 所属组

  class Meta:
    verbose_name_plural = "权限表"

  def __str__(self):
    return self.titlemodel

def init_permission(user, request):
  '''
  前端页面调用，把当前登录用户的权限放到session中，request参数指前端传入的当前当前login请求时的request
  :param user: 当前登录用户
  :param request: 当前请求
  :return: None
  '''
  # 拿到当前用户的权限信息
  permission_url_list = user.roles.values('permissions__group_id',
                      'permissions__code',
                      'permissions__url',
                      'permissions__group__menu__id',   # 菜单需要
                      'permissions__group__menu__title',  # 菜单需要
                      'permissions__title',  # 菜单需要
                      'permissions__url',   # 菜单需要
                      'permissions__is_menu', # 菜单需要
                      ).distinct()


  # 页面显示权限相关，用到了权限的分组,
  dest_dic = {}
  for each in permission_url_list:
    if each['permissions__group_id'] in dest_dic:
      dest_dic[each['permissions__group_id']]['code'].append(each['permissions__code'])
      dest_dic[each['permissions__group_id']]['per_url'].append(each['permissions__url'])
    else:
      # 刚循环，先创建需要的结构,并把第一次的值放进去。
      dest_dic[each['permissions__group_id']] = {'code': [each['permissions__code'], ],
                            'per_url': [each['permissions__url'], ]}

  request.session['permission_url_list'] = dest_dic

  # 页面菜单相关
  # 1.去掉不做菜单的url,拿到的结果是menu_list,列表中的元素是字典
  menu_list = []
  for item_dic in permission_url_list:
    if item_dic['permissions__is_menu']:
      temp = {'menu_id':item_dic['permissions__group__menu__id'],
          'menu_title':item_dic['permissions__group__menu__title'],
          'permission__title': item_dic['permissions__title'],
          'permission_url':item_dic['permissions__url'],
          'permissions__is_menu':item_dic['permissions__is_menu'],
          'active':False,  # 用于页面是否被选中，
          }
      # temp 其实只是给key重新起名字，之前的名字太长了。。。。
      menu_list.append(temp)
  # 执行完成之后是如下的数据，用来做菜单。

  request.session['permission_menu_list'] = menu_list

import re
from django.shortcuts import render,redirect,HttpResponse
from django.conf import settings

class MiddlewareMixin(object):
  def __init__(self, get_response=None):
    self.get_response = get_response
    super(MiddlewareMixin, self).__init__()

  def __call__(self, request):
    response = None
    if hasattr(self, 'process_request'):
      response = self.process_request(request)
    if not response:
      response = self.get_response(request)
    if hasattr(self, 'process_response'):
      response = self.process_response(request, response)
    return response

class M1(MiddlewareMixin):
  '''
  判断用户有无此url的权限的中间件
  '''
  def process_request(self,request):
    current_url = request.path_info

    # 1.白名单验证
    valid_url = settings.VALID_URL
    for each in valid_url:
      if re.match(each, current_url):
        return None

    # 2.验证是否已经写入session，即：是否已经登录
    permission_dic = request.session.get('permission_url_list')
    if not permission_dic:
      return redirect('/login/')

    # 3.与当前访问的url与权限url进行匹配验证,并在request中写入code信息，
    flag = False
    for group_id,code_urls in permission_dic.items():
      for url in code_urls['per_url']:
        regax = '^{0}$'.format(url)
        if re.match(regax,current_url):
          flag = True
          request.permission_code_list = code_urls['code'] # 在session中增加code的信息，用于在页面判断在当前页面的权限，
          break
      if flag:
        break

    if not flag:
      return HttpResponse('无权访问')


  def process_response(self,request,response):
    return response

import re

from django.template import Library

register = Library()

# inclusion_tag的结果是：把menu_html函数的返回值，放到menu_html中做渲染，生成一个渲染之后的大字符串，
# 在前端需要显示这个字符串的地方，只要调用menu_html就可以，如果有菜单需要传参数，这里是request,前端模板本来就有request,
@register.inclusion_tag('menu.html')
def menu_html(request):
  current_url = request.path_info

  # 结构化在页面显示的menu数据
  menu_list = request.session.get('permission_menu_list')

  menu_show_dic = {}
  for item in menu_list:
    # 先跟当前url进行匹配，如果当前的url在权限URl中，则需要修改当前的active，用于在前端页面的显示。
    url = item['permission_url']
    reg = '^{0}$'.format(url)
    if re.match(reg, current_url):
      print('匹配到了')
      item['active'] = True

    if item['menu_id'] in menu_show_dic:
      menu_show_dic[item['menu_id']]['children'].append(
        {'permission__title': item['permission__title'], 'permission_url': item['permission_url'],
         'active': item['active']})
      if item['active']:
        menu_show_dic[item['menu_id']]['active'] = True
    else:
      menu_show_dic[item['menu_id']] = {'menu_id': item['menu_id'],
                       'menu_title': item['menu_title'],
                       'active': False,
                       'children': [{'permission__title': item['permission__title'],
                              'permission_url': item['permission_url'],
                              'active': item['active']}, ]
                       }
      if item['active']:
        menu_show_dic[item['menu_id']]['active'] = True


  return {'menu_dic':menu_show_dic}

# menu.html

<div class="menu">
  {% for k,menu in menu_dic.items %}
    {# 一级菜单 #}
    <div class="menu_first">{{ menu.menu_title }}</div>

    {# 二级菜单(就是一级菜单下边的内容) #}
    {% if menu.active %}
      <ul class="">
    {% else %}
      <ul class="hide">
    {% endif %}

  {% for child in menu.children %}
    {% if child.active %}
      <li class="menu_second active"><a href="{{ child.permission_url }}" rel="external nofollow" rel="external nofollow" >{{ child.permission__title }}</a></li>
    {% else %}
      <li class="menu_second"><a href="{{ child.permission_url }}" rel="external nofollow" rel="external nofollow" >{{ child.permission__title }}</a></li>
    {% endif %}
  {% endfor %}
  </ul>
  {% endfor %}
</div>

# 这个是django的模板文件
{% load rbac %}

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>{% block title %}模板{% endblock %}</title>
  <link rel="stylesheet" href="{% static 'rbac/bootstrap-3.3.7/css/bootstrap.min.css' %}" rel="external nofollow" >
  <link rel="stylesheet" href="{% static 'rbac/menu.css' %}" rel="external nofollow" >
  {% block css %} {% endblock css %}

</head>
<body>
<div class="container-fluid">
  <div class="row">
    <div class="col-md-2 menu">
      {% block menu %}
        {% menu_html request %}  {# 用inclusion_tag生成的menu_html #}
      {% endblock menu %}
    </div>
    <div class="col-md-9">
      {% block content %}
      content
      {% endblock %}
    </div>
  </div>
</div>