flask完成登录验证

@app.before_request  # 请求前
def process_request(*args, **kwargs):
    print(request.path)
    if request.path == '/login' or request.path == '/':
        return None

    user = session.get('user_login')
    print(user, 1111111111111111111)
    if user:
        return None
    return redirect('/login')

# 请求后
@app.after_request
def process_response(response):
    return response

多个中间件执行先进后出,后进先出原则, 被拦截后忍让会执行所有响应