from django.http import HttpResponseRedirect
from django.shortcuts import render_to_response

def login(request):
username = request.POST.get('username', None)
if username:
request.session['username'] = username
username = request.session.get('username', None)
if username:
return render_to_response('login.html', {'username':username})
else:
return render_to_response('login.html')

def logout(request):
try:
del request.session['username']
except KeyError:
pass
return HttpResponseRedirect('/login')

{% if not username %}
<form method="post" action="/login/">
用户名：<input type="text" name="username" value=""><br/>
<input type="submit" value="登录">
</form>
{% else %}
{{ username }}，您已经登录了！<br/>
<form method="post" action="/logout/">
<input type="submit" value="注销">
</form>
{% endif %}

urlpatterns = patterns('',
(r'login/$', 'newtest.login.login'),
(r'logout/$', 'newtest.login.logout'),
)

5. 修改settings.py

Django的session需要使用数据库，Python 2.6中内置了sqlite3数据库，因此我们在这里直接使用sqlite3。sqlite3直接使用本地文件存储数据库，因此不存在服务器、端口、用户 名、密码、权限的配置问题，马上就可以开始使用，简单方便。

对newste/settings.py进行如下修改：

[quote]DATABASE_ENGINE = 'sqlite3'
DATABASE_NAME = './data.db'
DATABASE_USER = ''
DATABASE_PASSWORD = ''
DATABASE_HOST = ''
DATABASE_PORT = ''

You just installed Django's auth system, which means you don't have any superusers defined.
Would you like to create one now? (yes/no):