Python自学26 - Cookie和Session

from flask import Flask, make_response, request
​
app = Flask(__name__)
​
@app.route('/set_cookie')
def set_cookie():
    resp = make_response("Cookie 已设置")
    resp.set_cookie("username", "Alice", max_age=60*60)  # 1小时有效
    return resp
​
@app.route('/get_cookie')
def get_cookie():
    username = request.cookies.get("username")
    return f"当前用户: {username}" if username else "未找到 Cookie"
​
if __name__ == '__main__':
    app.run(debug=True)

from flask import Flask, session
​
app = Flask(__name__)
app.secret_key = "my_secret_key"  # 必须设置密钥
​
@app.route('/login')
def login():
    session['user'] = 'Alice'
    return "用户已登录"
​
@app.route('/profile')
def profile():
    user = session.get('user')
    return f"欢迎回来, {user}" if user else "请先登录"
​
@app.route('/logout')
def logout():
    session.pop('user', None)
    return "已退出登录"
​
if __name__ == '__main__':
    app.run(debug=True)

from flask import Flask, request, redirect, url_for, render_template_string, session, make_response
import datetime
​
app = Flask(__name__)
app.secret_key = "my_secret_key"  # 必须设置密钥
​
# 模拟用户数据库
users = {"alice": "123456", "bob": "password"}
​
# 简单的登录页面模板
login_page = """
<form method="POST">
  用户名: <input type="text" name="username"><br>
  密码: <input type="password" name="password"><br>
  <label><input type="checkbox" name="remember"> 记住我</label><br>
  <input type="submit" value="登录">
</form>
"""
​
@app.route('/')
def index():
    user = session.get('user')
    if user:
        return f"欢迎回来, {user}! <a href='/logout'>退出</a>"
    return "你还没有登录，<a href='/login'>去登录</a>"
​
@app.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'POST':
        username = request.form.get("username")
        password = request.form.get("password")
        remember = request.form.get("remember")
​
        # 校验用户名和密码
        if username in users and users[username] == password:
            session['user'] = username
            resp = make_response(redirect(url_for("index")))
​
            # 如果勾选了“记住我”，设置 Cookie 有效期 7 天
            if remember:
                expire_date = datetime.datetime.now() + datetime.timedelta(days=7)
                resp.set_cookie("remember_me", username, expires=expire_date)
            return resp
        else:
            return "用户名或密码错误！<a href='/login'>重试</a>"
    return render_template_string(login_page)
​
@app.before_request
def load_user_from_cookie():
    """如果 session 里没有用户，但 Cookie 里有，就自动登录"""
    if 'user' not in session:
        username = request.cookies.get("remember_me")
        if username in users:
            session['user'] = username
​
@app.route('/logout')
def logout():
    session.pop('user', None)
    resp = make_response("已退出登录 <a href='/'>返回首页</a>")
    resp.delete_cookie("remember_me")  # 删除 Cookie
    return resp
​
if __name__ == '__main__':
    app.run(debug=True)