python---django中权限框架设计

一：admin下的权限了解

推文：如何正确使用 Django的User Model

（一）默认权限表是在自带auth模块，中permission表中

可以使用has_perm方法获取用户是否有这个权限

（二）Django自定义权限

（1）添加表

from django.db import models
from django.contrib.auth.models import (
    BaseUserManager, AbstractBaseUser,PermissionsMixin
    #BaseUserManager　　用户管理基类，用于创建用户
    #AbstractBaseUser    抽象类，声明一些必须字段，不会自己生产表，继承的子类才会，主要内容:class Meta  abstract=True
    #PermissionMixin    权限管理类，也是抽象类
)

class MyUserManager(BaseUserManager):　　　#用于创建用户，需要在settings文件中声明
    def create_user(self, email, name, password=None):
        """
        Creates and saves a User with the given email, date of
        birth and password.
        """
        if not email:
            raise ValueError('Users must have an email address')

        user = self.model(
            email=self.normalize_email(email),
            name=name,
        )

        user.set_password(password)
        user.save(using=self._db)
        return user

    def create_superuser(self, email, name, password):
        """
        Creates and saves a superuser with the given email, date of
        birth and password.
        """
        user = self.create_user(
            email,
            password=password,
            name=name,
        )
        user.is_superuser = True
        user.save(using=self._db)
        return user

class UserProfile(AbstractBaseUser,PermissionsMixin):　　
    email = models.EmailField(
        verbose_name='email address',
        max_length=,
        unique=True,
    )
    name = models.CharField(max_length=)
    is_active = models.BooleanField(default=True)
    is_staff = models.BooleanField(default=True)
    # is_admin = models.BooleanField(default=False)　　#其中is_admin没有作用，is_superuser才是设置超级用户
    role = models.ManyToManyField("Role",blank=True)  #,null=Truenull has no effect on ManyToManyField.,null对于manytomanyfield无作用，会报警

    objects = MyUserManager()  #用户管理类和自定义用户表关联

    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = ['name']

    def __str__(self):
        return self.email

    def get_full_name(self):
        return self.email

    def get_short_name(self):
        return self.email

    class Meta:
        permissions = (　　#用于管理权限条目
              ('自定义权限名','解释'),
        )

（2）settings文件中设置

AUTH_USER_MODEL = 'repository.UserProfile' #上面的值表示Django应用的名称（必须位于INSTALLLED_APPS中）和你想使用的User模型的名称。

（3）在admin文件中设置展示内容

from django import forms
from django.contrib import admin
from django.contrib.auth.models import Group
from django.contrib.auth.admin import UserAdmin as BaseUserAdmin
from django.contrib.auth.forms import ReadOnlyPasswordHashField

from repository.models import UserProfile

class UserCreationForm(forms.ModelForm):　　#创建时显示的表单信息
    """A form for creating new users. Includes all the required
    fields, plus a repeated password."""
    password1 = forms.CharField(label='Password', widget=forms.PasswordInput)
    password2 = forms.CharField(label='Password confirmation', widget=forms.PasswordInput)

    class Meta:
        model = UserProfile
        fields = ('email', 'name')

    def clean_password2(self):　　#对字段进行验证
        # Check that the two password entries match
        password1 = self.cleaned_data.get("password1")
        password2 = self.cleaned_data.get("password2")
        if password1 and password2 and password1 != password2:
            raise forms.ValidationError("Passwords don't match")
        return password2

    def save(self, commit=True):　　
        # Save the provided password in hashed format
        user = super().save(commit=False)
        user.set_password(self.cleaned_data["password1"])
        if commit:
            user.save()
        return user

class UserChangeForm(forms.ModelForm):　　#修改时显示的表单信息
    """A form for updating users. Includes all the fields on
    the user, but replaces the password field with admin's
    password hash display field.
    """
    password = ReadOnlyPasswordHashField()　　#密码字段显示时是hash加密只读字段

    class Meta:
        model = UserProfile
        fields = ('email', 'password', 'name', 'is_active', 'is_superuser')

    def clean_password(self):
        # Regardless of what the user provides, return the initial value.
        # This is done here, rather than on the field, because the
        # field does not have access to the initial value
        return self.initial["password"]

class UserProfileAdmin(BaseUserAdmin):　　#用于注册的表类
    # The forms to add and change user instances
    form = UserChangeForm
    add_form = UserCreationForm

    # The fields to be used in displaying the User model.
    # These override the definitions on the base UserAdmin
    # that reference specific fields on auth.User.
    list_display = ('email', 'name', 'is_superuser')
    list_filter = ('is_superuser',)
    fieldsets = (   #用于修改
        (None, {'fields': ('email', 'password')}),
        ('Personal info', {'fields': ('name',)}),
        ('Permissions', {'fields': ('is_active','is_staff','is_superuser','role','user_permissions','groups',)}),
    )
    # add_fieldsets is not a standard ModelAdmin attribute. UserAdmin
    # overrides get_fieldsets to use this attribute when creating a user.
    add_fieldsets = (   #用于添加
        (None, {
            'classes': ('wide',),
            'fields': ('email', 'name', 'password1', 'password2')}
        ),
    )
    search_fields = ('email',)
    ordering = ('email',)
    filter_horizontal = ('role','user_permissions',)

# Now register the new UserAdmin...
admin.site.register(UserProfile, UserProfileAdmin)
# ... and, since we're not using Django's built-in permissions,
# unregister the Group model from admin.
admin.site.unregister(Group)

二：通用权限框架设计

（一）业务场景分析（如何去实现将不同权限分配给用户）

python---CRM用户关系管理

（二）权限管理分析

主要实现：将权限列表定义出来，与角色（用户组）相互关联就可以

权限列表实现：

（三）实现方法

（1）定义权限列表文件，将权限列表定义。设置为装饰器，根据每个用户访问的url去反解，获取到对应的权限列表名，从而去数据库中获取，使用has_prem获取是否拥有权限。从而在用户访问url时进行判断

permission_list.py（这部分最好是放入数据库中，可以改进）

from kingadmin import permission_hook

perm_dict = {
    'repository_table_obj_list':['table_obj_list',"GET",[],{},permission_hook.view_my_own_customers],　　
    #第一个是url_name,第二个是访问方式，第三个是访问参数必须有的字段，第四个是字段中必须是指定的值，第五个是钩子函数，是对第三，第四参数的补充，实现动态验证
    'repository_table_obj_change_view':['table_obj_change',"GET",[],{}],
    'repository_table_obj_change': ['table_obj_change', "POST", [], {}],
    'repository_table_obj_add_view': ['table_obj_add', "GET", [], {}],
    'repository_table_obj_add': ['table_obj_add', "POST", [], {}],
    'repository_table_obj_delete_view': ['table_obj_delete', "GET", [], {}],
    'repository_table_obj_delete': ['table_obj_delete', "POST", [], {}],
}

from django.conf.urls import url
from kingadmin import views

urlpatterns = [
    url(r"^login.html$",views.acc_login),
    url(r"^logout.html$", views.acc_logout,name="logout"),
    url(r"^$",views.app_index),
    url(r"^(\w+)/(\w+)/$",views.table_obj_list,name="table_obj_list"),
    url(r"^(\w+)/(\w+)/(\d+)/change/$", views.table_obj_change, name="table_obj_change"),
    url(r"^(\w+)/(\w+)/add/$", views.table_obj_add, name="table_obj_add"),
    url(r"^(\w+)/(\w+)/(\d+)/delete/$", views.table_obj_delete, name="table_obj_delete"),
]

urls文件，可以知道对应的url_name

resolve方法可以翻转获取url的数据

（2）permission文件，用于生成装饰器，验证权限列表

from .permission_list import perm_dict
from django.conf import settings
from django.core.urlresolvers import resolve
from django.shortcuts import render,redirect,HttpResponse

#对权限进行检测
def perm_check(*args,**kwargs):
    request = args[]
    resolve_url_obj = resolve(request.path)　　#1，获取当前请求的url
    current_url_name = resolve_url_obj.url_name　　#2，把url解析成url_name
    match_results = [None,]
    match_key = None
    if request.user.is_authenticated() is False:　　　#3，进行用户登录验证
return redirect(settings.LOGIN_URL)

    for permssion_key,permssion_val in perm_dict.items():
#从权限列表中获取url信息，以及钩子函数（重点）
        per_url_name = permssion_val[]
        per_method = permssion_val[]
        per_args = permssion_val[]
        per_kargs = permssion_val[]
        per_hook_name = permssion_val[] if len(permssion_val) >  else None

        if per_url_name == current_url_name:    #4.匹配url_name
if per_method == request.method:    #5.匹配访问方法
                args_matched = False    #用于匹配参数args，一次参数失败，则失败
                request_method_dict = getattr(request, per_method)
                for item in per_args:　　#6.匹配参数
if request_method_dict.get(item,None):
                        args_matched = True
                    else:
                        args_matched = False
                        break   #一次匹配不上，就跳出
                else:   #当不存在参数，列表为空时
                    args_matched = True

                kwargs_matched = False  #用于匹配特定的参数
                for k,v in per_kargs.items():　　#7.匹配指定参数值
                    arg_val = request_method_dict.get(k,None)
                    if arg_val == str(v):
                        kwargs_matched = True
                    else:
                        kwargs_matched = False
                else:
                    kwargs_matched = True

                hook_matched = False
                if per_hook_name:　　#8.匹配钩子函数
                    hook_matched = per_hook_name(request)
                else:
                    hook_matched = True

                match_results = [args_matched,kwargs_matched,hook_matched]

                if all(match_results):  #9.都匹配了　　全局验证，获取了权限名，用于下面数据库查询
                    match_key = permssion_key
                    break

    if match_key:
        app_name,*per_name = match_key.split("_")
        perm_obj = "%s.%s"%(app_name,match_key)
        if request.user.has_perm(perm_obj):　　#10.数据库查看用户是否被分配该权限
            print("当前用户有权限")
            return True
        else:
            print("当前用户没有权限")
            return False
    else:
        print("未匹配到权限项，当前用户没有权限")
        return False

#装饰器函数
def check_permission(func):
    def inner(*args,**kwargs):
        if not perm_check(*args,**kwargs):
            request = args[]
            return render(request,"kingadmin/page_403.html")
        return func(*args,**kwargs)
    return inner

总结：

def perm_check(*args,**kwargs):
    .获取当前请求的url，使用resolve解析获取url_name
    .匹配用户是否登录，使用user.is_authenticated方法
    .使用url_name去权限列表permission_list文件中的权限列表中去匹配权限项
    .将权限项解析分为，per_url_name(权限url_name),per_method (url访问方法),per_args (获取的参数名),per_kargs (获取的参数值，字典),per_hook_name (获取的权限钩子函数)
    .验证了上面的几部分，获取了权限名，然后去数据库中获取当前用户是否拥有该权限，使用user.has_perm(权限名<注意：权限名是由数据表应用加上权限名>)

（3）钩子函数案例（使当前用户只能访问自己的客户）

def view_my_own_customers(request):
    if str(request.user.id) == request.GET.get('consultant'):
        return True
    else:
        return False