Django：视图views（三）

写一下Cookie、重定向、Session

Cookie

测试代码，承接前面的代码：

路由： booktest/urls.py

urlpatterns = [
    url('^$',views.index), # 路由到views.py中的index()函数
    url('^index', views.index, name="index"),
    url('^(\d+)$', views.integer),
    url('^(?P<p2>\d+)/(?P<p3>\d+)/(?P<p1>\d+)$', views.date),
    url('^req$', views.req),
    url('^resp$', views.resp),
    url('^cookie$', views.cookie),
]

booktest/views.py

def cookie(request):
    resp = HttpResponse('cookie')
    resp.set_cookie('name', 'zhangsan')
    return resp

访问 http://127.0.0.1:8080/booktest/cookie  - “查看元素/检查”- “网络”- 左边选择浏览的网页 - 右边查看响应头

此时cookies就保存到浏览器上

然后可以把服务器上的代码set_cookie去掉

def cookie(request):
    resp = HttpResponse('cookie')
    #resp.set_cookie('name', 'zhangsan')
    return resp

访问同一个网页 http://127.0.0.1:8080/booktest/cookie  检查

由于之前的cookies已经保存到浏览器上了，所以现在就把浏览器上的cookie发送到服务端。

接下来需要服务器去接收cookie

路由 booktest/urls.py

urlpatterns = [
    url('^$',views.index), # 路由到views.py中的index()函数
    url('^index', views.index, name="index"),
    url('^(\d+)$', views.integer),
    url('^(?P<p2>\d+)/(?P<p3>\d+)/(?P<p1>\d+)$', views.date),
    url('^req$', views.req),
    url('^resp$', views.resp),
    url('^cookie$', views.cookie),
    url('^cookie2$', views.cookie2),
]

视图 booktest/views.py

def cookie2(request):
    resp = HttpResponse()
    cookie = request.COOKIES
    if 'name' in cookie:
        resp.write(cookie['name'])
    return resp

访问http://127.0.0.1:8080/booktest/cookie2  就会把cookie发送到服务器，然后服务器端获取name的值，并显示出来

重定向

重定向是指服务器端跳转。

直接把请求指向另外一个地方

路由 booktest/urls.py

urlpatterns = [
    url('^$',views.index), # 路由到views.py中的index()函数
    url('^index', views.index, name="index"),
    url('^(\d+)$', views.integer),
    url('^(?P<p2>\d+)/(?P<p3>\d+)/(?P<p1>\d+)$', views.date),
    url('^req$', views.req),
    url('^resp$', views.resp),
    url('^cookie$', views.cookie),
    url('^cookie2$', views.cookie2),
    url('^redirect$', views.redirect),
    url('^redirect2$', views.redirect2),
]

视图 booktest/views.py

from django.shortcuts import render
from django.http import HttpResponse, HttpResponseRedirect
from django.template import loader, RequestContext
def redirect(request):
    return HttpResponseRedirect('/booktest/redirect2')

def redirect2(request):
    return HttpResponse('这里重定向后的页面')

Session

首先需要打开数据库的功能。

django3/settings.py

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'django3',
        'USER': 'root',
        'PASSWORD': '',
        'HOST': 'localhost',
        'PORT': ''
    }
}

确保INSTALL_APP中已经打开了session的功能

INSTALLED_APPS = (
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'booktest'
)

确保MIDDLEWARE_CLASSES中也添加了SESSION的功能

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

如果要禁用session的话，把上面两个值注释掉就好了

进行迁移。如果没有添加booktest的app，可以使用--empty参数

python manage.py makemigrations --empty booktest
python manage.py migrate

确保数据库中生成django_session表

编写首页

booktest/urls.py

urlpatterns = [
    url('^$',views.index), # 路由到views.py中的index()函数
    url('^index', views.index, name="index"),
    url('^(\d+)$', views.integer),
    url('^(?P<p2>\d+)/(?P<p3>\d+)/(?P<p1>\d+)$', views.date),
    url('^req$', views.req),
    url('^resp$', views.resp),
    url('^cookie$', views.cookie),
    url('^cookie2$', views.cookie2),
    url('^redirect$', views.redirect),
    url('^redirect2$', views.redirect2),
    url('^session1$', views.session1),
]

booktest/views.py

def session1(request):
    uname = None
    context = {"uname":uname}
    return render(request, 'booktest/session1.html', context)

templates/booktest/session1.html

<body>
    欢迎：{{uname}}
    <hr/>
    <a href="#">登录</a>
    <hr/>
    <a href="#">退出</a>
</body>

编写登录页面

booktest/urls.py

urlpatterns = [
    url('^$',views.index), # 路由到views.py中的index()函数
    url('^index', views.index, name="index"),
    url('^(\d+)$', views.integer),
    url('^(?P<p2>\d+)/(?P<p3>\d+)/(?P<p1>\d+)$', views.date),
    url('^req$', views.req),
    url('^resp$', views.resp),
    url('^cookie$', views.cookie),
    url('^cookie2$', views.cookie2),
    url('^redirect$', views.redirect),
    url('^redirect2$', views.redirect2),
    url('^session1$', views.session1),
    url('^session2$', views.session2),
]

booktest/views.py

def session2(request):
    return render(request, 'booktest/session2.html')

templates/booktest/session1.html

<body>
    欢迎：{{uname}}
    <hr/>
    <a href="/booktest/session2">登录</a>
    <hr/>
    <a href="#">退出</a>
</body>

templates/booktest/session2.html

<body>
    <form method="post" action="/booktest/session2_handler">
        <input type="text" name="uname"/>
        <input type="submit" value="登录"/>
    </form>
</body>

处理登录请求

booktest/urls.py

urlpatterns = [
    url('^$',views.index), # 路由到views.py中的index()函数
    url('^index', views.index, name="index"),
    url('^(\d+)$', views.integer),
    url('^(?P<p2>\d+)/(?P<p3>\d+)/(?P<p1>\d+)$', views.date),
    url('^req$', views.req),
    url('^resp$', views.resp),
    url('^cookie$', views.cookie),
    url('^cookie2$', views.cookie2),
    url('^redirect$', views.redirect),
    url('^redirect2$', views.redirect2),
    url('^session1$', views.session1),
    url('^session2$', views.session2),
    url('^session2_handler$', views.session2_handler),
]

booktest/views.py

def session2_handler(request):
    post = request.POST
    uname = post['uname']
    request.session['uname'] = uname
    return HttpResponseRedirect('/booktest/session1')

数据库的django_session表中出现了

这里的session_key是故意写的这么复杂，以防重复的。而session_data是经过base64编码的，可以使用 https://base64.supfree.net/ 进行解码

解码后的结果如下：

修改session1，从session中获取值

booktest/views.py

def session1(request):
    uname = request.session.get('uname', '未登陆')
    context = {"uname":uname}
    return render(request, 'booktest/session1.html', context)

登录后，则显示用户名

退出登录

booktest/urls.py

urlpatterns = [
    url('^$',views.index), # 路由到views.py中的index()函数
    url('^index', views.index, name="index"),
    url('^(\d+)$', views.integer),
    url('^(?P<p2>\d+)/(?P<p3>\d+)/(?P<p1>\d+)$', views.date),
    url('^req$', views.req),
    url('^resp$', views.resp),
    url('^cookie$', views.cookie),
    url('^cookie2$', views.cookie2),
    url('^redirect$', views.redirect),
    url('^redirect2$', views.redirect2),
    url('^session1$', views.session1),
    url('^session2$', views.session2),
    url('^session2_handler$', views.session2_handler),
    url('^session3$', views.session3),
]

booktest/views.py

def session3(request):
    request.session['uname'] = None
    return HttpResponseRedirect('/booktest/session1')

添加退出登录的链接

templates/booktest/session3.html

<body>
    欢迎：{{uname}}
    <hr/>
    <a href="/booktest/session2">登录</a>
    <hr/>
    <a href="/booktest/session3">退出</a>
</body>

通过set_expiry()函数设置过期时间。如果没有设置，默认在两个星期后过期

如果你想浏览器退出的时候马上过期，可以设置参数为0

def session2_handler(request):
    post = request.POST
    uname = post['uname']
    request.session['uname'] = uname
    request.session.set_expiry(0)
    return HttpResponseRedirect('/booktest/session1')

把session保存到redis中

django3/settings.py

SESSION_ENGINE = 'redis_sessions.session'
SESSION_REDIS_HOST = 'localhost'
SESSION_REDIS_PORT = 6379
SESSION_REDIS_DB = 0
SESSION_REDIS_PASSWORD = ''
SESSION_REDIS_PREFIX = 'session'

需要安装插件django-redis-sessions

pip install django-redis-sessions

登录后就可以在redis中查看session的信息了