session保存信息用数据库

cookie保存数据，防止访问后端页面，只能先登陆，保存在客户端数据信息，包括用户名密码

session也是保存数据，优势是保存在服务端数据库中

views页面

from django.shortcuts import render,redirect

# Create your views here.
def login(req):
    print("COOKIES",req.COOKIES)
    print("SESSION",req.session)#要想提示session必须在settings把MIDDLEWARE改成MIDDLEWARE_CLASSES
    if req.method=="POST":
        name=req.POST.get("user")
        pwd=req.POST.get("pwd")
        if name=="tom"and pwd=="123":
            # ret=redirect("index.html")#跳转某个页面
            # ret.set_cookie("username",name)#键值对形式，此处name是tom
            # return ret

            #cookie加session
            req.session["isLogin"]=True
            req.session["user"] = True

            return redirect("index.html")

    return render(req,"login.html")

def index(req):
    # if req.COOKIES.get("username",None):
#
#          name=req.COOKIES.get("username",None)
#          return render(req,"index.html",locals())
#     else:
#          return redirect("login.html")
    #session
    if req.session.get("isLogin",None):
        name=req.session.get("user",None)
        return render(req,"index.html",locals())
    else:
      return redirect("login.html")

settings修改middleware

"""
Django settings for COOKIE project.

Generated by 'django-admin startproject' using Django 1.11.3.

For more information on this file, see
https://docs.djangoproject.com/en/1.11/topics/settings/

For the full list of settings and their values, see
https://docs.djangoproject.com/en/1.11/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/1.11/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = 't=i9-c%%$as+9&j00%(2pqybf9=m_4d8p-e=wh%t+fy=9h@4^n'

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

ALLOWED_HOSTS = []


# Application definition

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'app.apps.AppConfig',
]

MIDDLEWARE_CLASSES = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    #'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

ROOT_URLCONF = 'COOKIE.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 = 'COOKIE.wsgi.application'


# Database
# https://docs.djangoproject.com/en/1.11/ref/settings/#databases

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
    }
}


# Password validation
# https://docs.djangoproject.com/en/1.11/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/1.11/topics/i18n/

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'UTC'

USE_I18N = True

USE_L10N = True

USE_TZ = True


# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/1.11/howto/static-files/

STATIC_URL = '/static/'

然后terminal输入 python manage.py makemigrations

python manage.py migrate 

python manage.py runserver 8800

生成数据库，session必须要有保存信息的数据库