1、rbac权限组件-初识， 中间件校验1

1、权限组件rbac

1、什么是权限

1 项目与应用

2 什么是权限？

一个包含正则表达式url就是一个权限

who what how ---------->True or Flase

2、版本1：用户表与权限url表 对应关系

    # 版本1

     UserInfor

         name
         pwd
         permission=models.manytomany(Permission)

        name   pwd
        egon
        alex
        A
        B
        C
        D      

     Permission

        url=.....
          title=....

    id       url            title
         "/users/"         "查看用户"
         "/users/add/"     "添加用户"
         "/customer/add"    "添加客户"

     UserInfor_permission

        id
        user_id
        permission_id        

        id    user_id   permission_id

    示例：登录人：egon
          访问url:http://127.0.0.1:8000/users/    

          def users(request):

             user_id=request.session.get("user_id")

             obj=UserInfor.objects.filter(pk=user_id).first()
             obj.permission.all().valuelist("url")

             return HttpResponse("users.....")
         

3、版本2： 用户--》角色--》权限

    UserInfor

         name
         pwd
         roles

        name   pwd
        egon
        alex
        alex
        alex
        alex
        alex
        alex
        alex
        alex       

    Role

       title=.......
       permissions=......

         id   title
            销售员

    UserInfor2Role

       id     user_id    role_id    

    Permission

        url=.....
          title=....

    id       url            title
         "/users/"         "查看用户"
         "/users/add/"     "添加用户"
         "/customer/add"    "添加客户"

    Role2Permission

    id  role_id   permission_id    

      rbac（role-based access control） 

2、代码实现

1）项目目录结构

2）数据库表

from django.db import models

# Create your models here.

class User(models.Model):
    name = models.CharField(max_length=32)
    pwd = models.CharField(max_length=32)
    roles = models.ManyToManyField(to='Role')

    def __str__(self):
        return self.name

class Role(models.Model):
    title = models.CharField(max_length=32)
    permissions = models.ManyToManyField(to="Permission")

    def __str__(self):
        return self.title

class Permission(models.Model):
    title = models.CharField(max_length=32)
    url = models.CharField(max_length=32)

    def __str__(self):
        return self.title

3）admin添加数据

创建超级用户 alex

注册数据表

from django.contrib import admin

# Register your models here.

from .models import *

admin.site.register(User)
admin.site.register(Role)
admin.site.register(Permission)

3、登录验证

1、session中注册用户，权限

1.在session中注册用户ID
    request.session['user_id'] = user.pk

2.初始化 permission_list 并注册到session 中
    initial_session(user,request)

注意点：

permission = user.roles.all().values('permission__url').distinct()

1.values:      
    temp = []
    for role in user.roles.all():  # < QuerySet[ < Role: 保洁 >, < Role: 销售 >] >
        temp.append({
            'title':role.title
            'permission__url': role.permission__url.all()
        })
    return temp

2.values 不会去重！！
    <QuerySet [{'title': '保洁', 'permission__url': '/users/'}, 
    {'title': '销售', 'permission__url': '/users/'}, 
    {'title': '销售', 'permission__url': '/users/add'}]>  

2、解耦

def initial_session(request,user):
    permissions = user.roles.all().values("permissions__url").distinct()

    permission_list = []
    for item in permissions:
        permission_list.append(item['permissions__url'])

    print(permission_list)  # ['/users/', '/users/add', '/users/delete/(\\d+)', '/users/edit/(\\d+)']

    request.session["permission_list"] = permission_list

    """
    values :

    for role in user.roles.all():   # <QuerySet [<Role: 保洁>, <Role: 销售>]>
        temp.append({
        "title":role.title,
        "permissions_url":role.permissions.all()
        })

    # <QuerySet [{'title': '保洁', 'permissions__url': '/users/'},
    # {'title': '销售', 'permissions__url': '/users/'},
    # {'title': '销售', 'permissions__url': '/users/add'}]>

    """

4、基于中间件的权限校验

1、middleware如何构造？抄袭

2、正则匹配

from django.test import TestCase

# Create your tests here.

# 当前path 如何与 paths匹配
# 不能用in   /users/delete/9
# 正则匹配

li = ['/users/', '/users/add', '/users/delete/(\\d+)', '/users/edit/(\\d+)']

c_path = "/users/delete/9"

import re

flag = False

for permission in li:
    permission = "^%s$" % permission
    ret = re.match(permission, c_path)
    if ret:
        flag = True
        break

if flag:
    print("success")

# ret = re.match("/users/", "/users/delete/9")
ret = re.match("^/users/$", "/users/delete/9")
print(ret)

3、admin如何验证：302重定向

3、构建中间件

# -*- coding: utf-8 -*-
# @Time    : 2018/08/11 0011 9:04
# @Author  : Venicid

import re

from django.utils.deprecation import MiddlewareMixin
from django.shortcuts import HttpResponse, redirect

class ValidPermission(MiddlewareMixin):
    def process_request(self, request):

        # 当前访问路径
        current_path = request.path_info

        # 1、检验是否属于白名单  白名单，不需要任何权限的url
                # 正则匹配
        valid_url_list = ['/login/','/reg/','/admin/.*']
        for valid_url in valid_url_list:
            ret = re.match(valid_url, current_path)

            if ret:
                return None

        # 2、校验是否登录
        user_id = request.session.get("user_id")
        if not user_id:
            return redirect('/login/')

        # 3、校验权限
        permission_list = request.session.get("permission_list",[])

        flag = False
        for permission in permission_list:
            permission = "^%s$" % permission
            ret = re.match(permission, current_path)
            if ret:
                flag = True
                break

        if not flag:
            return HttpResponse("没有访问权限")
        return None

4、views视图，url

url

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

from app01 import views

urlpatterns = [
    path('admin/', admin.site.urls),
    re_path(r'^users/$',views.users),
    re_path(r'^users/add/$',views.add_user),
    re_path(r'^roles/$',views.roles),
    re_path(r'^login/$',views.login),
]

views

from django.shortcuts import render, HttpResponse

# Create your views here.

from rbac.models import *

def users(request):
    user_list = User.objects.all()

    return render(request, "users.html", locals())

def add_user(request):

    """
    permission_list = request.session["permission_list"]  # # ['/users/', '/users/add', '/users/delete/(\\d+)', '/users/edit/(\\d+)']
    current_path = request.path_info

    flag = False
    for permission in permission_list:
        permission = "^%s$"%permission
        ret = re.match(permission, current_path)
        if ret:
            flag = True
            break

    if not flag:
        return  HttpResponse("没有访问权限")
    """
    return HttpResponse('add user')

def roles(request):
    role_list = Role.objects.all()
    print(role_list)

    # 方式2 middleware

    """
    # 方式1
    permission_list = request.session["permission_list"]  # # ['/users/', '/users/add', '/users/delete/(\\d+)', '/users/edit/(\\d+)']
    current_path = request.path_info

    flag = False
    for permission in permission_list:
        permission = "^%s$"%permission
        ret = re.match(permission, current_path)
        if ret:
            flag = True
            break

    if not flag:
        return  HttpResponse("没有访问权限")
    """

    return render(request, "roles.html", locals())

from rbac.service.perssions import *
def login(request):
    if request.method == "POST":
        user = request.POST.get("user")
        pwd = request.POST.get("pwd")

        user = User.objects.filter(name=user, pwd=pwd).first()
        if user:

            ############## 在session中注册用户
            request.session['user_id'] = user.pk

            ############# 在session中注册权限list

            # 查询当前登录用户的所有角色
            # ret = user.roles.all()
            # print(ret)   # <QuerySet [<Role: 保洁>, <Role: 销售>]>

            # 查询当前登录用户的所有权限

            initial_session(request, user)

            return HttpResponse("登录成功")

    return render(request, 'login.html', locals())

5、注意点

注意点：

1.白名单，不需要任何权限的url
    valid_url_list = ['/login/', '/reg/', '/admin/.*']
    for valid_url in valid_url_list:
        ret = re.match(valid_url, current_path)
        if ret:
            return

    正则匹配

2.校验是否登录，
    user_id = request.session.get('user_id')
    if not user_id:
        return redirect('/login/')

3.校验权限（^ $ / 正则）
    permission_list = request.session.get('permission_list',[])

    flag = False
    for permission in permission_list:
        # ['/users/', '/users/add/', '/users/edit/(\\d+)/', '/users/delete/(\\d+)/']
        # 需要 ^ $ 限定！！ 
        permission = "^%s$" % permission

        # 正则
        ret = re.match(permission, current_path)
        if ret:
            flag = True
            break

    if not flag:
        return HttpResponse('无访问权限！')

4、总结：关于rbac

关于rbac： 

    (1) 创建表关系：
        class User(models.Model):
            name=models.CharField(max_length=32)
            pwd=models.CharField(max_length=32)
            roles=models.ManyToManyField(to="Role")

            def __str__(self): return self.name

        class Role(models.Model):
            title=models.CharField(max_length=32)
            permissions=models.ManyToManyField(to="Permission")

            def __str__(self): return self.title

        class Permission(models.Model):
            title=models.CharField(max_length=32)
            url=models.CharField(max_length=32)

            def __str__(self):return self.title

    (2) 基于admin录入数据

    (3) 登录校验：

        if 登录成功:

            查询当前登录用户的权限列表注册到session中

    (4) 校验权限（中间件的应用）
        class ValidPermission(MiddlewareMixin):

            def process_request(self,request):

                # 当前访问路径
                current_path = request.path_info

                # 检查是否属于白名单
                valid_url_list=["/login/","/reg/","/admin/.*"]

                for valid_url in valid_url_list:
                    ret=re.match(valid_url,current_path)
                    if ret:
                        return None

                # 校验是否登录

                user_id=request.session.get("user_id")

                if not user_id:
                    return redirect("/login/")

                # 校验权限
                permission_list = request.session.get("permission_list",[])  # ['/users/', '/users/add', '/users/delete/(\\d+)', 'users/edit/(\\d+)']

                flag = False
                for permission in permission_list:

                    permission = "^%s$" % permission

                    ret = re.match(permission, current_path)
                    if ret:
                        flag = True
                        break
                if not flag:
                    return HttpResponse("没有访问权限！")

                return None