网站监控脚本触发RecursionError问题求助

问题重现 #

用户编写的网站监控脚本运行时抛出错误：

RecursionError: maximum recursion depth exceeded while calling a Python object

原脚本代码：

import requests
import datetime
import time
from discord_webhook import DiscordWebhook, DiscordEmbed

s = requests.Session()
headers = {}  # 需补充实际请求头

def login(userName, passWord):
    data = {
        'loginID': userName,
        'password': passWord,
        'btnallgo': 'SUBMIT',
    }
    print(f'[{datetime.now()}] | Posting Login => [asp]')
    response = s.post('http://bcps.browardschools.com/virtualcounselor/bsvc/loginstudent.asp', headers=headers, data=data, verify=False)

login('#yourusername','#yourpassword')

def monitor():
    params = {
        'markper': '1',
    }
    print(f'[{datetime.now()}] | Checking Content => [get/asp]')
    response = s.get('https://bcps.browardschools.com/VirtualCounselor/bsvc/studentsched.asp', params=params, headers=headers)
    print(f'[{datetime.now()}] | Page Response => [{response.content}]')
    if response.content == (b'<P align=center><font color=red size=3><b>Your class schedule is currently unavailable.<br><br><br> Thank You</b></P>'):
        print(f'[{datetime.now()}] | Schedule unavailable, retrying')
        time.sleep(2.4)
        monitor()
        
    elif response.content == (b'\r\n\r\n\r\n<HTML>\r\n<HEAD>\r\n<TITLE>APPLICATION TIMEOUT</TITLE></HEAD>\r\n<BODY BGCOLOR=WHITE LINK=RED ALINK=RED VLINK=RED>\r\n<P ALIGN=CENTER><BR><BR><FONT COLOR=RED SIZE=5>- APPLICATION HAS TIMED OUT -</FONT><BR><BR>FOR SECURITY MEASURES YOUR SESSION HAS TIMED OUT<BR>AFTER 15 MINUTES OF INACTIVITY OR WHEN YOU LOGGED OFF.<BR>PLEASE <A HREF="https://bcps.browardschools.com/virtualcounselor" TARGET="_parent">CLICK HERE</A> TO RELOGIN.</P>\r\n</BODY>\r\n</HTML> \r\n\r\n'):
        print(f'Generating new session{response.status_code}')
        login()
    
    else:
        print(f'[{datetime.now()}] | Page Updated => {response.content}')
        webhook = DiscordWebhook(url='#yourwebhookhere')
        embed = DiscordEmbed(title='Page Update', description=f'{response.text}', color='03b2f8')
        embed.set_timestamp()
        webhook.add_embed(embed)
        response = webhook.execute()
        if response.status_code == 200:
            print(f'Sent webhook[status:{response.status_code}]')
        else:
            print(f'Error sending webhook[status:{response.status_code}]')
        
refresh = monitor()

问题原因 #

脚本中monitor函数在检测到日程不可用时，通过递归调用自身实现循环重试。Python默认递归深度限制为1000左右，当重试次数超过这个限制时，就会触发RecursionError。此外，超时分支中login()调用未传入用户名和密码参数，也会导致后续运行报错。

解决方案 #

方案1：用while循环替代递归（推荐） #

将递归逻辑改为无限循环，彻底避免递归深度限制问题，同时修复login调用的参数问题：

import requests
import datetime
import time
from discord_webhook import DiscordWebhook, DiscordEmbed

s = requests.Session()
headers = {}  # 补充实际请求头
USERNAME = '#yourusername'
PASSWORD = '#yourpassword'
WEBHOOK_URL = '#yourwebhookhere'

def login(userName, passWord):
    data = {
        'loginID': userName,
        'password': passWord,
        'btnallgo': 'SUBMIT',
    }
    print(f'[{datetime.now()}] | Posting Login => [asp]')
    response = s.post('http://bcps.browardschools.com/virtualcounselor/bsvc/loginstudent.asp', headers=headers, data=data, verify=False)

def monitor():
    login(USERNAME, PASSWORD)
    while True:
        params = {
            'markper': '1',
        }
        print(f'[{datetime.now()}] | Checking Content => [get/asp]')
        try:
            response = s.get('https://bcps.browardschools.com/VirtualCounselor/bsvc/studentsched.asp', params=params, headers=headers)
            print(f'[{datetime.now()}] | Page Response => [{response.content[:100]}...]')  # 截断输出避免过长
        except Exception as e:
            print(f'[{datetime.now()}] | Request failed: {str(e)}')
            time.sleep(5)
            continue

        unavailable_msg = b'<P align=center><font color=red size=3><b>Your class schedule is currently unavailable.<br><br><br> Thank You</b></P>'
        timeout_msg = b'\r\n\r\n\r\n<HTML>\r\n<HEAD>\r\n<TITLE>APPLICATION TIMEOUT</TITLE></HEAD>\r\n<BODY BGCOLOR=WHITE LINK=RED ALINK=RED VLINK=RED>\r\n<P ALIGN=CENTER><BR><BR><FONT COLOR=RED SIZE=5>- APPLICATION HAS TIMED OUT -</FONT><BR><BR>FOR SECURITY MEASURES YOUR SESSION HAS TIMED OUT<BR>AFTER 15 MINUTES OF INACTIVITY OR WHEN YOU LOGGED OFF.<BR>PLEASE <A HREF="https://bcps.browardschools.com/virtualcounselor" TARGET="_parent">CLICK HERE</A> TO RELOGIN.</P>\r\n</BODY>\r\n</HTML> \r\n\r\n'

        if response.content == unavailable_msg:
            print(f'[{datetime.now()}] | Schedule unavailable, retrying')
            time.sleep(2.4)
        elif response.content == timeout_msg:
            print(f'[{datetime.now()}] | Session timed out, re-logging in')
            login(USERNAME, PASSWORD)
            time.sleep(1)
        else:
            print(f'[{datetime.now()}] | Page Updated => {response.content[:100]}...')
            try:
                webhook = DiscordWebhook(url=WEBHOOK_URL)
                embed = DiscordEmbed(title='Page Update', description=f'{response.text[:500]}...', color='03b2f8')
                embed.set_timestamp()
                webhook.add_embed(embed)
                webhook_response = webhook.execute()
                if webhook_response.status_code == 200:
                    print(f'Sent webhook[status:{webhook_response.status_code}]')
                else:
                    print(f'Error sending webhook[status:{webhook_response.status_code}]')
            except Exception as e:
                print(f'[{datetime.now()}] | Webhook failed: {str(e)}')
            # 发送通知后可选择退出或继续监控，这里设置继续
            time.sleep(60)  # 更新后延迟再监控

if __name__ == '__main__':
    monitor()

关键改进点：

• 用while True无限循环替代递归调用，彻底摆脱递归深度限制
• 将用户名、密码、Webhook URL抽成全局常量，避免重复硬编码
• 修复超时分支中login()的参数缺失问题
• 添加异常捕获，处理请求或Webhook发送失败的情况
• 截断过长的输出内容，避免控制台刷屏

方案2：调整递归深度限制（不推荐） #

如果坚持使用递归，可以通过sys.setrecursionlimit提高递归深度，但这只是临时解决方案，仍存在栈溢出风险，且无法真正实现无限运行：

import sys
sys.setrecursionlimit(10000)  # 提高递归深度限制

同时需要修复超时分支的login()参数问题：login(USERNAME, PASSWORD)。但这种方法本质上还是依赖递归，长期运行仍可能触发错误，因此不推荐。

内容的提问来源于stack exchange，提问作者user19422024