Flask之 Session

from flask import Flask, session, redirect, url_for, escape, request

app = Flask(__name__)

@app.route('/')
def index():
    #判断username是否存在session中
    if 'username' in session:
        return 'Logged in as %s' % escape(session['username'])
    return 'You are not logged in'

@app.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'POST':
        #设置session username为输入的表单值
        session['username'] = request.form['username']
        #重定向到首页
        return redirect(url_for('index'))
    return '''
        <form action="" method="post">
            <p><input type=text name=username>
            <p><input type=submit value=Login>
        </form>
    '''

@app.route('/logout')
def logout():
    # 移除一个username session
    session.pop('username', None)
    return redirect(url_for('index'))

#设置一个安全key
app.secret_key = 'A0Zr98j/3yX R~XHH!jmN]LWX/,?RT'

app.run()