flask--session组件

简介

flask-session是flask框架的session组件，由于原来flask内置session使用签名cookie保存，该组件则将支持session保存到多个地方，如：

• redis：保存数据的一种工具，五大类型。非关系型数据库
• memcached
• filesystem
• mongodb
• sqlalchmey：那数据存到数据库表里面

安装

pip install flask-session

存储方式

from flask import Flask,session
from flask_session import RedisSessionInterface
app = Flask(__name__)
app.secret_key = 'asdf'

# 默认
# from flask.sessions import SecureCookieSessionInterface
# app.session_interface = SecureCookieSessionInterface()
# 方式一：redis 保存session
# from redis import Redis
# app.session_interface = RedisSessionInterface(
#     redis=Redis(host='127.0.0.1',port=6379),
#     key_prefix='flaskxxx'
# )
# 方式二：redis 保存session
from flask_session import Session
from redis import Redis
app.config['SESSION_TYPE'] = 'redis'
app.config['SESSION_REDIS'] = Redis(host='192.168.0.94',port='6379')
Session(app)


@app.route('/login')
def login():
    session['k1'] = 123
    return 'login'

@app.route('/xx')
def index():
    v = session['k1']
    print(v)
    return 'Index'

if __name__ == '__main__':
    app.wsgi_app
    app.run()

总体步骤分为两步

应用：
    a. 配置
        app.config['SESSION_TYPE'] = 'redis'
        app.config['SESSION_REDIS'] = Redis(host='192.168.0.94',port='6379')
        
    b. 替换 
        from flask_session import Session
        Session(app)

注意点：

session中存储的是字典，修改字典内部元素时，会造成数据不更新，解决方法

1- motified = True
2- SESSION_REFRESH_EACH_REQUEST = True and  session.permanent = True(redis中默认)

示例

from flask import Blueprint,render_template,request,session,redirect
from uuid import uuid4
account = Blueprint('account',__name__)


@account.route('/login',methods=['GET',"POST"])
def login():
    if request.method == 'GET':
        return render_template('login.html')
    user = request.form.get('user')
    pwd = request.form.get('pwd')
    if user == 'alex' and pwd == '123':
        uid = str(uuid4())
        session.permanent = True
        session['user_info'] = {'id':uid, 'name':user}
        return redirect('/index')
    else:
        return render_template('login.html',msg='用户名或密码错误')

配置文件中还要设置SESSION_REFRESH_EACH_REQUEST = True

其它类型的存储方式

memcached

#!/usr/bin/env python
# -*- coding:utf-8 -
import redis
from flask import Flask, session
from flask_session import Session
import memcache

app = Flask(__name__)
app.debug = True
app.secret_key = 'xxxx'


app.config['SESSION_TYPE'] = 'memcached' # session类型为redis
app.config['SESSION_PERMANENT'] = True # 如果设置为True，则关闭浏览器session就失效。
app.config['SESSION_USE_SIGNER'] = False # 是否对发送到浏览器上session的cookie值进行加密
app.config['SESSION_KEY_PREFIX'] = 'session:' # 保存到session中的值的前缀
app.config['SESSION_MEMCACHED'] = memcache.Client(['10.211.55.4:12000'])


Session(app)


@app.route('/index')
def index():
    session['k1'] = 'v1'
    return 'xx'


if __name__ == '__main__':
    app.run()

filesystem

#!/usr/bin/env python
# -*- coding:utf-8 -
import redis
from flask import Flask, session
from flask_session import Session

app = Flask(__name__)
app.debug = True
app.secret_key = 'xxxx'

app.config['SESSION_TYPE'] = 'filesystem'  # session类型为redis
app.config[
    'SESSION_FILE_DIR'] = '/Users/wupeiqi/PycharmProjects/grocery/96.Flask新课程/组件/2.flask-session'  # session类型为redis
app.config['SESSION_FILE_THRESHOLD'] = 500  # 存储session的个数如果大于这个值时，就要开始进行删除了
app.config['SESSION_FILE_MODE'] = 384  # 文件权限类型

app.config['SESSION_PERMANENT'] = True  # 如果设置为True，则关闭浏览器session就失效。
app.config['SESSION_USE_SIGNER'] = False  # 是否对发送到浏览器上session的cookie值进行加密
app.config['SESSION_KEY_PREFIX'] = 'session:'  # 保存到session中的值的前缀

Session(app)


@app.route('/index')
def index():
    session['k1'] = 'v1'
    session['k2'] = 'v1'
    return 'xx'


if __name__ == '__main__':
    app.run()

mongodb

#!/usr/bin/env python
# -*- coding:utf-8 -
import redis
from flask import Flask, session
from flask_session import Session
import pymongo

app = Flask(__name__)
app.debug = True
app.secret_key = 'xxxx'

app.config['SESSION_TYPE'] = 'mongodb'  # session类型为redis

app.config['SESSION_MONGODB'] = pymongo.MongoClient()
app.config['SESSION_MONGODB_DB'] = 'mongo的db名称（数据库名称）'
app.config['SESSION_MONGODB_COLLECT'] = 'mongo的collect名称（表名称）'

app.config['SESSION_PERMANENT'] = True  # 如果设置为True，则关闭浏览器session就失效。
app.config['SESSION_USE_SIGNER'] = False  # 是否对发送到浏览器上session的cookie值进行加密
app.config['SESSION_KEY_PREFIX'] = 'session:'  # 保存到session中的值的前缀

Session(app)


@app.route('/index')
def index():
    session['k1'] = 'v1'
    session['k2'] = 'v1'
    return 'xx'


if __name__ == '__main__':
    app.run()

mongodb操作简单示例：

#!/usr/bin/env python
# -*- coding:utf-8 -*-
from pymongo import MongoClient

# 创建链接
conn = MongoClient('47.93.4.198', 27017)

# 选择数据库
db = conn['db1']

# 选择表
posts = db['posts']

post_data = {
    'name': 'alex',
    'age': 18
}

# 表中插入数据
# result = posts.insert_one(post_data)

# 获取一条数据
# row = posts.find_one()
# print(row)

# # 获取多条数据
# rows = posts.find()
# for row in rows:
#     print(row)

# 删除多条数据
# rows = posts.delete_many(filter={})
# print(rows)

# 更新多条数据
# posts.update({}, {'name': 'wupeiqi'})

sqlalchemy

#!/usr/bin/env python
# -*- coding:utf-8 -
import redis
from flask import Flask, session
from flask_session import Session as FSession
from flask_sqlalchemy import SQLAlchemy

app = Flask(__name__)
app.debug = True
app.secret_key = 'xxxx'

# 设置数据库链接
app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql+pymysql://root:123@127.0.0.1:3306/fssa?charset=utf8'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True

# 实例化SQLAlchemy
db = SQLAlchemy(app)



app.config['SESSION_TYPE'] = 'sqlalchemy'  # session类型为sqlalchemy
app.config['SESSION_SQLALCHEMY'] = db # SQLAlchemy对象
app.config['SESSION_SQLALCHEMY_TABLE'] = 'session' # session要保存的表名称
app.config['SESSION_PERMANENT'] = True  # 如果设置为True，则关闭浏览器session就失效。
app.config['SESSION_USE_SIGNER'] = False  # 是否对发送到浏览器上session的cookie值进行加密
app.config['SESSION_KEY_PREFIX'] = 'session:'  # 保存到session中的值的前缀
FSession(app)


@app.route('/index')
def index():

    session['k1'] = 'v1'
    session['k2'] = 'v1'

    return 'xx'


if __name__ == '__main__':
    app.run()

PS: 在写好代码后，不要着急运行，需要先执行进入终端执行一条创建数据库表的命令：

bogon:pro-flask wupeiqi$ python3
Python 3.5.1 (v3.5.1:37a07cee5969, Dec  5 2015, 21:12:44)
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from app import db
>>> db.create_all()
>>>