Django rest framework源码分析(一) 认证

一、基础

最近正好有机会去写一些可视化的东西,就想着前后端分离,想使用django rest framework写一些,顺便复习一下django rest framework的知识,只是顺便哦,好吧。我承认我是故意的,因为我始终觉得,如果好的技术服务于企业,顺便的提高一下自己。大家都很开心不是不。再次强调一下,真的只是顺便。

安装吧

pip install djangorestframework

  

1.2.需要先了解的一些知识

理解下面两个知识点非常重要,django-rest-framework源码中到处都是基于CBV和面向对象的封装

(1)面向对象封装的两大特性

把同一类方法封装到类中

将数据封装到对象中

  

(2)CBV

基于反射实现根据请求方式不同,执行不同的方法

原理:url-->view方法-->dispatch方法(反射执行其它方法:GET/POST/PUT/DELETE等等)

二、简单实例

2.1.settings

先创建一个project和一个app(我这里命名为API)

首先要在settings的app中添加,这里我把正则setting全部贴出来吧

"""
Django settings for API_TEST project.

Generated by 'django-admin startproject' using Django 1.9.7.

For more information on this file, see
https://docs.djangoproject.com/en/1.9/topics/settings/

For the full list of settings and their values, see
https://docs.djangoproject.com/en/1.9/ref/settings/
"""

import os

# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))


# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/1.9/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = 'r!2z#wgp-v!3afygp=owoie10a(d*p4xwg+z*kcv039#klnp-r'

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True

ALLOWED_HOSTS = ['*',]   # 这里需要你修改一下,临时用用


# Application definition

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'API.apps.ApiConfig',
    'API_TEST',        # 这里需要你添加一下自己的APP名字
    'rest_framework',    # 这里需要你添加一下
]

MIDDLEWARE_CLASSES = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    # 'django.middleware.csrf.CsrfViewMiddleware',   # 这里需要临时注释一下哦
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

ROOT_URLCONF = 'API_TEST.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [os.path.join(BASE_DIR, 'templates')]
        ,
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug',
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
            ],
        },
    },
]

WSGI_APPLICATION = 'API_TEST.wsgi.application'


# Database
# https://docs.djangoproject.com/en/1.9/ref/settings/#databases

# DATABASES = {
#     'default': {
#         'ENGINE': 'django.db.backends.sqlite3',
#         'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
#     }
# }
# 这里是关于数据库相关配置,最好不要使用windows哦,我的环境是python2.7的,安装一下mysql连接器包的时候有问题,所以最好升级一下自己的pip 
DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'test',
        'USER': 'root',
        'PASSWORD': 'root1234',
        'HOST': '172.26.4.202',
        'PORT': '3306',
    }
}

# Password validation
# https://docs.djangoproject.com/en/1.9/ref/settings/#auth-password-validators

AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
    },
]


# Internationalization
# https://docs.djangoproject.com/en/1.9/topics/i18n/

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'UTC'  # 这里最好也改一下吧。我是测试,无所谓了,生产上还是需要修改的

USE_I18N = True

USE_L10N = True

USE_TZ = True


# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/1.9/howto/static-files/

STATIC_URL = '/static/'

# 这里是和认证相关的,目前这里你用不到哦
REST_FRAMEWORK = {
    'DEFAULT_AUTHENTICATION_CLASSES': ['API.utils.auth.Authentication',],
}
                    

  

2.2.url

from django.contrib import admin
from django.urls import path
from API.views import AuthView

urlpatterns = [
    path('admin/', admin.site.urls),
    path('api/v1/auth/',AuthView.as_view()),
]

  

2.3.models

一个保存用户的信息

一个保存用户登录成功后的token

from django.db import models

class UserInfo(models.Model):
    USER_TYPE = (
        (1,'普通用户'),
        (2,'VIP'),
        (3,'SVIP')
    )

    user_type = models.IntegerField(choices=USER_TYPE)
    username = models.CharField(max_length=32)
    password = models.CharField(max_length=64)

class UserToken(models.Model):
    user = models.OneToOneField(UserInfo,on_delete=models.CASCADE)
    token = models.CharField(max_length=64)

  

2.4.views

用户登录(返回token并保存到数据库)

from django.shortcuts import render
from django.http import JsonResponse
from rest_framework.views import APIView
from API import models

def md5(user):
    import hashlib
    import time
    #当前时间,相当于生成一个随机的字符串
    ctime = str(time.time())
    m = hashlib.md5(user)
    m.update(ctime)
    return m.hexdigest()

class AuthView(object):
    def post(self,request,*args,**kwargs):
        ret = {'code':1000,'msg':None}
        try:
            user = request._request.POST.get('username')
            pwd = request._request.POST.get('password')
            obj = models.UserInfo.objects.filter(username=user,password=pwd).first()
            if not obj:
                ret['code'] = 1001
                ret['msg'] = '用户名或密码错误'
            #为用户创建token
            token = md5(user)
            #存在就更新,不存在就创建
            models.UserToken.objects.update_or_create(user=obj,defaults={'token':token})
            ret['token'] = token
        except Exception as e:
            ret['code'] = 1002
            ret['msg'] = '请求异常'
        return JsonResponse(ret)

  

2.5.利用postman发请求

Django rest framework源码分析(一) 认证_第1张图片

如果用户名和密码正确的话  会生成token值,下次该用户再登录时,token的值就会更新

 数据库中可以看到token的值

 Django rest framework源码分析(一) 认证_第2张图片

当用户名或密码错误时,抛出异常

Django rest framework源码分析(一) 认证_第3张图片

 

 三、添加认证

进入到今天的主角了,开始认证了,认证使用装饰器不,好吧,这里不使用装饰器。

 基于上面的例子,添加一个认证的类

3.1.url

from django.conf.urls import url
from django.contrib import admin
from API import views
urlpatterns = [
    # url(r'^admin/', admin.site.urls),
    url(r'api/v1/auth', views.AuthView.as_view()),
    url(r'api/v1/order', views.OrderView.as_view()),
]

  

views.py

#!/usr/bin/env python
# coding:utf-8
from django.shortcuts import render

from django.http import JsonResponse
from rest_framework.views import APIView
from API import models
from rest_framework.request import Request
from rest_framework import exceptions
from rest_framework.authentication import BasicAuthentication


import hashlib
import time
def md5(user):
    ctime = str(time.time())
    m = hashlib.md5(user)
    m.update(ctime)
    return m.hexdigest()


class AuthView(APIView):
    authentication_classes = []
    def post(self,request,*args,**kwargs):
        ret = {'code': 1000,'msg':None}
        try:
            user = request.POST.get('username')
            pwd = request.POST.get('password')
            print(user,pwd)
            obj = models.UserInfo.objects.filter(username=user,password=pwd).first()
            print('=============%s' %(obj))
            if not obj:
                ret['code'] = 1001
                ret['msg'] = '用户名或者密码错误'
            # 为用户创建token
            token = md5(user)
            # 存在就更新,不存在就创建
            models.UserToken.objects.update_or_create(user=obj,defaults={'token':token})
            ret['token'] = token
        except Exception as e:
            ret['code'] = 1002
            ret['msg'] = '请求异常'

        # user = request._request.POST.get('username')
        # pwd = request._request.POST.get('password')
        # print(user,pwd)
        # obj = models.UserInfo.objects.filter(username=user,password=pwd).first()
        # print('=============%s' %(obj))
        # if not obj:
        #     ret['code'] = 1001
        #     ret['msg'] = '用户名或者密码错误'
        # # 为用户创建token
        # token = md5(user)
        # # 存在就更新,不存在就创建
        # models.UserToken.objects.update_or_create(user=obj,defaults={'token':token})
        # ret['token'] = token
        # return JsonResponse(ret)

ORDER_DICT = {
    1: {
        'name': 'apple',
        'price': 15,
    },
    2: {
        'name': 'dog',
        'price': 100
    }
}
class Authentication(APIView):
    """
    认证类
    """
    def authenticate(self,request):
        token = request._request.GET.get('token')
        token_obj = models.UserToken.objects.filter(token=token).first()
        if not token_obj:
            raise exceptions.AuthenticationFailed('用户认证失败')
        # 在rest framework内部会将这2个字段赋值给request,以供后续使用
        return (token_obj.user,token_obj)

    def authenticate_header(self,reqeust):
        pass

class OrderView(APIView):
    """订单相关业务"""
    # authentication_classes = [] # 添加认证
    def get(self,request,*args,**kwargs):
        print(request.user)
        print(request.auth)
        ret = {'code':1000,'msg':None, 'data': None}
        try:
            ret['data'] = ORDER_DICT
        except Exception as e:
            pass
        return JsonResponse(ret)

  

3.3用postman发get请求

请求的时候没有带token,可以看到会显示“用户认证失败”

 Django rest framework源码分析(一) 认证_第4张图片

 这样就达到了认证的效果,django-rest-framework的认证是怎么实现的呢,下面基于这个例子来剖析drf的源码。

 

四、drf的认证源码分析

好吧,我是骗你的,上面的还是配角,今天的主角现在才开始出现。

源码流程图

Django rest framework源码分析(一) 认证_第5张图片

请求先到dispatch

dispatch()主要做了两件事

  • 封装request
  • 认证  

具体看我写的代码里面的注释

def dispatch(self, request, *args, **kwargs):
        """
        `.dispatch()` is pretty much the same as Django's regular dispatch,
        but with extra hooks for startup, finalize, and exception handling.
        """
        self.args = args
        self.kwargs = kwargs
        #对原始request进行加工,丰富了一些功能
        #Request(
        #     request,
        #     parsers=self.get_parsers(),
        #     authenticators=self.get_authenticators(),
        #     negotiator=self.get_content_negotiator(),
        #     parser_context=parser_context
        # )
        #request(原始request,[BasicAuthentications对象,])
        #获取原生request,request._request
        #获取认证类的对象,request.authticators
        #1.封装request
        request = self.initialize_request(request, *args, **kwargs)
        self.request = request
        self.headers = self.default_response_headers  # deprecate?

        try:
            #2.认证
            self.initial(request, *args, **kwargs)

            # Get the appropriate handler method
            if request.method.lower() in self.http_method_names:
                handler = getattr(self, request.method.lower(),
                                  self.http_method_not_allowed)
            else:
                handler = self.http_method_not_allowed

            response = handler(request, *args, **kwargs)

        except Exception as exc:
            response = self.handle_exception(exc)

        self.response = self.finalize_response(request, response, *args, **kwargs)
        return self.response

  

4.1.reuqest

(1)initialize_request()

可以看到initialize()就是封装原始request

def initialize_request(self, request, *args, **kwargs):
        """
        Returns the initial request object.
        """
        parser_context = self.get_parser_context(request)

        return Request(
            request,
            parsers=self.get_parsers(),
            authenticators=self.get_authenticators(),    #[BasicAuthentication(),],把对象封装到request里面了
       negotiator=self.get_content_negotiator(), parser_context=parser_context )

  

(2)get_authenticators()

通过列表生成式,返回对象的列表

    def get_authenticators(self):
        """
        Instantiates and returns the list of authenticators that this view can use.
        """
        return [auth() for auth in self.authentication_classes]

  

(3)authentication_classes

 APIView里面有个  authentication_classes   字段

可以看到默认是去全局的配置文件找(api_settings)

class APIView(View):

    # The following policies may be set at either globally, or per-view.
    renderer_classes = api_settings.DEFAULT_RENDERER_CLASSES
    parser_classes = api_settings.DEFAULT_PARSER_CLASSES
    authentication_classes = api_settings.DEFAULT_AUTHENTICATION_CLASSES
    throttle_classes = api_settings.DEFAULT_THROTTLE_CLASSES
    permission_classes = api_settings.DEFAULT_PERMISSION_CLASSES
    content_negotiation_class = api_settings.DEFAULT_CONTENT_NEGOTIATION_CLASS
    metadata_class = api_settings.DEFAULT_METADATA_CLASS
    versioning_class = api_settings.DEFAULT_VERSIONING_CLASS

  

4.2.认证

self.initial(request, *args, **kwargs)

 

def dispatch(self, request, *args, **kwargs):
        """
        `.dispatch()` is pretty much the same as Django's regular dispatch,
        but with extra hooks for startup, finalize, and exception handling.
        """
        self.args = args
        self.kwargs = kwargs
        #对原始request进行加工,丰富了一些功能
        #Request(
        #     request,
        #     parsers=self.get_parsers(),
        #     authenticators=self.get_authenticators(),
        #     negotiator=self.get_content_negotiator(),
        #     parser_context=parser_context
        # )
        #request(原始request,[BasicAuthentications对象,])
        #获取原生request,request._request
        #获取认证类的对象,request.authticators
        #1.封装request
        request = self.initialize_request(request, *args, **kwargs)
        self.request = request
        self.headers = self.default_response_headers  # deprecate?

        try:
            #2.认证
            self.initial(request, *args, **kwargs)

            # Get the appropriate handler method
            if request.method.lower() in self.http_method_names:
                handler = getattr(self, request.method.lower(),
                                  self.http_method_not_allowed)
            else:
                handler = self.http_method_not_allowed

            response = handler(request, *args, **kwargs)

        except Exception as exc:
            response = self.handle_exception(exc)

        self.response = self.finalize_response(request, response, *args, **kwargs)
        return self.response

  

(1)initial()

 主要看 self.perform_authentication(request),实现认证

def initial(self, request, *args, **kwargs):
        """
        Runs anything that needs to occur prior to calling the method handler.
        """
        self.format_kwarg = self.get_format_suffix(**kwargs)

        # Perform content negotiation and store the accepted info on the request
        neg = self.perform_content_negotiation(request)
        request.accepted_renderer, request.accepted_media_type = neg

        # Determine the API version, if versioning is in use.
        version, scheme = self.determine_version(request, *args, **kwargs)
        request.version, request.versioning_scheme = version, scheme

        # Ensure that the incoming request is permitted
        #3.实现认证
        self.perform_authentication(request)
        self.check_permissions(request)
        self.check_throttles(request)

  

(2)perform_authentication()

 调用了request.user

def perform_authentication(self, request):
        """
        Perform authentication on the incoming request.

        Note that if you override this and simply 'pass', then authentication
        will instead be performed lazily, the first time either
        `request.user` or `request.auth` is accessed.
        """
        request.user

  

(3)user

request.user的request的位置

Django rest framework源码分析(一) 认证_第6张图片

点进去可以看到Request有个user方法,加 @property 表示调用user方法的时候不需要加括号“user()”,可以直接调用:request.user

@property
    def user(self):
        """
        Returns the user associated with the current request, as authenticated
        by the authentication classes provided to the request.
        """
        if not hasattr(self, '_user'):
            with wrap_attributeerrors():
                #获取认证对象,进行一步步的认证
                self._authenticate()
        return self._user

  

(4)_authenticate()

 循环所有authenticator对象,这里的对象还记得是谁传递过来的不,Request那边传过来的,尼玛,今天再看突然看懂了。这里最终是通过settings的配置文件中定义你的认证类的路径,然后找到你的认证类,然后在这边循环的,最终执行你认证类中的认证方法

def _authenticate(self):
        """
        Attempt to authenticate the request using each authentication instance
        in turn.
        """
        #循环认证类的所有对象
        #执行对象的authenticate方法
        for authenticator in self.authenticators:
            try:
                #执行认证类的authenticate方法
                #这里分三种情况
                #1.如果authenticate方法抛出异常,self._not_authenticated()执行
                #2.有返回值,必须是元组:(request.user,request.auth)
                #3.返回None,表示当前认证不处理,等下一个认证来处理
                user_auth_tuple = authenticator.authenticate(self)
            except exceptions.APIException:
                self._not_authenticated()
                raise

            if user_auth_tuple is not None:
                self._authenticator = authenticator
                self.user, self.auth = user_auth_tuple
                return

        self._not_authenticated()

  

返回值就是例子中的:

token_obj.user-->>request.user
token_obj-->>request.auth
这俩货就是

UserInfo object
UserToken object

其实request.user 和 request.auth 都是封装在了Request.py中的2个特殊方法,为啥说他们特殊呢,因为在方法中加入了@property的装饰器,这个装饰器加上,我们在调用的时候就可以像调用属性的写法那样调用方法了,是不是很有意思呢。

    @property
    def auth(self):
        """
        Returns any non-user authentication information associated with the
        request, such as an authentication token.
        """
        if not hasattr(self, '_auth'):
            with wrap_attributeerrors():
                self._authenticate()
        return self._auth

  

是2个对象。

#在rest framework内部会将这两个字段赋值给request,以供后续操作使用
return (token_obj.user,token_obj)     #例子中的return

  

当都没有返回值,就执行self._not_authenticated(),相当于匿名用户,没有通过认证

def _not_authenticated(self):
        """
        Set authenticator, user & authtoken representing an unauthenticated request.

        Defaults are None, AnonymousUser & None.
        """
        self._authenticator = None

        if api_settings.UNAUTHENTICATED_USER:
            self.user = api_settings.UNAUTHENTICATED_USER()   #AnonymousUser匿名用户
        else:
            self.user = None

        if api_settings.UNAUTHENTICATED_TOKEN:
            self.auth = api_settings.UNAUTHENTICATED_TOKEN()  #None
        else:
            self.auth = None

  

面向对象知识:

子类继承 父类,调用方法的时候:

  • 优先去自己里面找有没有这个方法,有就执行自己的
  • 只有当自己里面没有这个方法的时候才会去父类找

 因为authenticate方法我们自己写,所以当执行authenticate()的时候就是执行我们自己写的认证

父类中的authenticate方法

    def authenticate(self, request):
        return (self.force_user, self.force_token)

  

 我们自己写的

class Authentication(APIView):
    '''用于用户登录验证'''
    def authenticate(self,request):
        token = request._request.GET.get('token')
        token_obj = models.UserToken.objects.filter(token=token).first()
        if not token_obj:
            raise exceptions.AuthenticationFailed('用户认证失败')
        #在rest framework内部会将这两个字段赋值给request,以供后续操作使用
        return (token_obj.user,token_obj)

  

 认证的流程就是上面写的,弄懂了原理,再写代码就更容易理解为什么了。

4.3.配置文件

继续解读源码  

Django rest framework源码分析(一) 认证_第7张图片

默认是去全局配置文件中找,所以我们应该在settings.py中配置好路径

api_settings源码

api_settings = APISettings(None, DEFAULTS, IMPORT_STRINGS)


def reload_api_settings(*args, **kwargs):
    setting = kwargs['setting']
    if setting == 'REST_FRAMEWORK':
        api_settings.reload()

  

setting中‘REST_FRAMEWORK’中找

 全局配置方法:

API文件夹下面新建文件夹utils,再新建auth.py文件,里面写上认证的类

settings.py

#设置全局认证
REST_FRAMEWORK = {
    "DEFAULT_AUTHENTICATION_CLASSES":['API.utils.auth.Authentication',]   #里面写你的认证的类的路径
}

  

auth.py

# API/utils/auth.py

from rest_framework import exceptions
from API import models


class Authentication(object):
    '''用于用户登录验证'''
    def authenticate(self,request):
        token = request._request.GET.get('token')
        token_obj = models.UserToken.objects.filter(token=token).first()
        if not token_obj:
            raise exceptions.AuthenticationFailed('用户认证失败')
        #在rest framework内部会将这两个字段赋值给request,以供后续操作使用
        return (token_obj.user,token_obj)

    def authenticate_header(self, request):
        pass

  

在settings里面设置的全局认证,所有业务都需要经过认证,如果想让某个不需要认证,只需要在其中添加下面的代码:

authentication_classes = []    #里面为空,代表不需要认证

  

#!/usr/bin/env python
# coding:utf-8
from django.shortcuts import render

from django.http import JsonResponse
from rest_framework.views import APIView
from API import models
from rest_framework.request import Request
from rest_framework import exceptions
from rest_framework.authentication import BasicAuthentication


import hashlib
import time
def md5(user):
    ctime = str(time.time())
    m = hashlib.md5(user)
    m.update(ctime)
    return m.hexdigest()


class AuthView(APIView):
    authentication_classes = []
    def post(self,request,*args,**kwargs):
        ret = {'code': 1000,'msg':None}
        try:
            user = request.POST.get('username')
            pwd = request.POST.get('password')
            print(user,pwd)
            obj = models.UserInfo.objects.filter(username=user,password=pwd).first()
            print('=============%s' %(obj))
            if not obj:
                ret['code'] = 1001
                ret['msg'] = '用户名或者密码错误'
            # 为用户创建token
            token = md5(user)
            # 存在就更新,不存在就创建
            models.UserToken.objects.update_or_create(user=obj,defaults={'token':token})
            ret['token'] = token
        except Exception as e:
            ret['code'] = 1002
            ret['msg'] = '请求异常'

        # user = request._request.POST.get('username')
        # pwd = request._request.POST.get('password')
        # print(user,pwd)
        # obj = models.UserInfo.objects.filter(username=user,password=pwd).first()
        # print('=============%s' %(obj))
        # if not obj:
        #     ret['code'] = 1001
        #     ret['msg'] = '用户名或者密码错误'
        # # 为用户创建token
        # token = md5(user)
        # # 存在就更新,不存在就创建
        # models.UserToken.objects.update_or_create(user=obj,defaults={'token':token})
        # ret['token'] = token
        # return JsonResponse(ret)

ORDER_DICT = {
    1: {
        'name': 'apple',
        'price': 15,
    },
    2: {
        'name': 'dog',
        'price': 100
    }
}
# class Authentication(APIView):
#     """
#     认证类
#     """
#     def authenticate(self,request):
#         token = request._request.GET.get('token')
#         token_obj = models.UserToken.objects.filter(token=token).first()
#         if not token_obj:
#             raise exceptions.AuthenticationFailed('用户认证失败')
#         # 在rest framework内部会将这2个字段赋值给request,以供后续使用
#         return (token_obj.user,token_obj)
# 
#     def authenticate_header(self,reqeust):
#         pass

class OrderView(APIView):
    """订单相关业务"""
    # authentication_classes = [] # 添加认证
    def get(self,request,*args,**kwargs):
        print(request.user)
        print(request.auth)
        ret = {'code':1000,'msg':None, 'data': None}
        try:
            ret['data'] = ORDER_DICT
        except Exception as e:
            pass
        return JsonResponse(ret)

  

再测试一下我们的代码

不带token发请求

Django rest framework源码分析(一) 认证_第8张图片

带token发请求

Django rest framework源码分析(一) 认证_第9张图片

 

 

 

五、drf的内置认证

 rest_framework里面内置了一些认证,我们自己写的认证类都要继承内置认证类 "BaseAuthentication"

4.1.BaseAuthentication源码:

class BaseAuthentication(object):
    """
    All authentication classes should extend BaseAuthentication.
    """

    def authenticate(self, request):
        """
        Authenticate the request and return a two-tuple of (user, token).
        """
        #内置的认证类,authenticate方法,如果不自己写,默认则抛出异常
        raise NotImplementedError(".authenticate() must be overridden.")

    def authenticate_header(self, request):
        """
        Return a string to be used as the value of the `WWW-Authenticate`
        header in a `401 Unauthenticated` response, or `None` if the
        authentication scheme should return `403 Permission Denied` responses.
        """
        #authenticate_header方法,作用是当认证失败的时候,返回的响应头
        pass

  

4.2.修改自己写的认证类

自己写的Authentication必须继承内置认证类BaseAuthentication

 

# API/utils/auth/py

from rest_framework import exceptions
from API import models
from rest_framework.authentication import BaseAuthentication


class Authentication(BaseAuthentication):
    '''用于用户登录验证'''
    def authenticate(self,request):
        token = request._request.GET.get('token')
        token_obj = models.UserToken.objects.filter(token=token).first()
        if not token_obj:
            raise exceptions.AuthenticationFailed('用户认证失败')
        #在rest framework内部会将这两个字段赋值给request,以供后续操作使用
        return (token_obj.user,token_obj)

    def authenticate_header(self, request):
        pass

  

4.3.其它内置认证类

rest_framework里面还内置了其它认证类,我们主要用到的就是BaseAuthentication,剩下的很少用到

Django rest framework源码分析(一) 认证_第10张图片

六、总结

 

自己写认证类方法梳理

 (1)创建认证类

  • 继承BaseAuthentication    --->>1.重写authenticate方法;2.authenticate_header方法直接写pass就可以(这个方法必须写)

(2)authenticate()返回值(三种)

  • None ----->>>当前认证不管,等下一个认证来执行
  • raise exceptions.AuthenticationFailed('用户认证失败')       # from rest_framework import exceptions
  •  有返回值元祖形式:(元素1,元素2)      #元素1复制给request.user;  元素2复制给request.auth

 (3)局部使用

  • authentication_classes = [BaseAuthentication,]

(4)全局使用

#设置全局认证
REST_FRAMEWORK = {
    "DEFAULT_AUTHENTICATION_CLASSES":['API.utils.auth.Authentication',]
}

  

源码流程

--->>dispatch

    --封装request

       ---获取定义的认证类(全局/局部),通过列表生成式创建对象 

     ---initial

       ----peform_authentication

         -----request.user   (每部循环创建的对象)

 

终于抄写完成了哈哈。写到这里,听到一个好玩的事情,一个开发问:公司怎么啊? 同事回答:“你觉得应该怎么翻,当然是用你的手和你的脚了”。

今天抽烟突然想通了很多事情,有些人注定逝去,有些人在你的生命中昙花一现,有些人在你的生命中来来回回。所以,抽烟有害健康,及时戒烟可以不要胡思乱想。

 

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