Bottle Sessions with Redis
Bottle_session is a session manager for the Bottle microframework that uses a cookie to maintain your web session and stores a hash associated with that cookie using the redis key-value store. It is designed as a simple Bottle plugin.
Installation
Install using either pip or easy_install:
$ pip install bottle-session
or you can download the latest version from bitbucket:
$ git clone https://devries@bitbucket.org/devries/bottle-session.git
$ cd bottle-session
$ python setup.py install
Requirements
In order to use bottle-session you must have both the redis and of course the bottle modules installed. I recommend also installing pycrypto, although it is not required. If pycrypto is installed, then the pycrypto random number generator is used to generate session cookies, otherwise python's internal random number generator is used.
Using Bottle-session
The first requirement is that you import the bottle_session module:
:::python
import bottle_session
import bottle
Next, initialize the plugin:
:::python
app = bottle.app()
plugin = bottle_session.SessionPlugin(cookie_lifetime=600)
app.install(plugin)
The cookie_lifetime
parameter is the lifetime of the cookie in seconds, if
the lifetime is explicitly set to None it will last 1 week. The
SessionPlugin
class initializer takes several optional parameters:
host
is the host for the redis instance. It defaults tolocalhost
.port
is the port for the redis instance. It defaults to6379
.db
is the redis database number. It defaults to0
.cookie_name
is the name of the session cookie. It defaults tobottle.session
.cookie_secure
is a boolean variable to set the Secure cookie flag. It defaults toFalse
.cookie_httponly
is a boolean variable to set the HttpOnly cookie flag. It defaults toFalse
.keyword
is the plugin keyword. It defaults tosession
.password
is the optional password for the redis instance. It defaults to none.
To use the plugin, just add the keyword (session
by default) to the routed
method:
:::python
@bottle.route('/')
def index(session):
user_name = session.get('name')
if user_name is not None:
return "Hello, %s"%user_name
else:
return "I don't recognize you."
@bottle.route('/set/:user_name')
def set_name(session,user_name=None):
if user_name is not None:
session['name']=user_name
return "I recognize you now."
else:
return "What was that?"
bottle.debug(True)
bottle.run(app=app,host='localhost',port=8888)
In this example you can set the name
property of the session cookie to Chris
by visiting the http://localhost:8888/set/Chris
and then that value is
retrieved when you visit http://localhost:8888/
.
Using Bottle-session and Bottle-redis
If you are using redis for sessions you are likely using redis to store other data as well, and likely use the bottle-redis plugin. You can use both plugins together, and you can even get them to use the same connection pool. Initialize them by creating a connection pool which you attach to each plugin object before installing them into the bottle application as shown below:
:::python
#!/usr/bin/env python
import bottle_session
import bottle_redis
import bottle
import redis
from datetime import datetime
app = bottle.app()
session_plugin = bottle_session.SessionPlugin()
redis_plugin = bottle_redis.RedisPlugin()
connection_pool = redis.ConnectionPool(host='localhost', port=6379)
session_plugin.connection_pool = connection_pool
redis_plugin.redisdb = connection_pool
app.install(session_plugin)
app.install(redis_plugin)
@bottle.route('/')
def index(session,rdb):
rdb.incr('visitors')
visitor = rdb.get('visitors')
last_visit = session['visit']
session['visit'] = datetime.now().isoformat()
return 'You are visitor %s, your last visit was on %s'%(visitor,last_visit)
bottle.debug(True)
bottle.run(app=app,host='localhost',port=8888)
Acknowledgments
Thanks to Marcel Hellkamp and the bottle community for the framework and to Sean M. Collins whose bottle-redis package in bottle-extras served as the inspiration for this bottle plugin. Thank you to James Burke for your contributions.