树莓派5上Cron运行Python+Selenium+Chromedriver报错求助

环境与问题 #

• 树莓派5运行Debian Bookworm系统
• 因官方无ARM版Chromedriver，通过APT安装适配版本
• Python脚本在Geany编辑器及用户终端运行正常，但通过crontab -e配置定时执行时出现启动失败错误

报错信息 #

Traceback (most recent call last):   File "/home/dean/main_venv/luxpowerdl.py", line 69, in <module>
    driver = webdriver.Chrome(service=service)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   File "/home/dean/main_venv/lib/python3.11/site-packages/selenium/webdriver/chrome/webdriver.py", line 45, in __init__
    super().__init__(   File "/home/dean/main_venv/lib/python3.11/site-packages/selenium/webdriver/chromium/webdriver.py", line 61, in __init__
    super().__init__(command_executor=executor, options=options)   File "/home/dean/main_venv/lib/python3.11/site-packages/selenium/webdriver/remote/webdriver.py", line 208, in __init__
    self.start_session(capabilities)   File "/home/dean/main_venv/lib/python3.11/site-packages/selenium/webdriver/remote/webdriver.py", line 292, in start_session
    response = self.execute(Command.NEW_SESSION, caps)["value"]
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   File "/home/dean/main_venv/lib/python3.11/site-packages/selenium/webdriver/remote/webdriver.py", line 347, in execute
    self.error_handler.check_response(response)   File "/home/dean/main_venv/lib/python3.11/site-packages/selenium/webdriver/remote/errorhandler.py", line 229, in check_response
    raise exception_class(message, screen, stacktrace) selenium.common.exceptions.SessionNotCreatedException: Message: session not created: Chrome failed to start: exited normally.   (session not created: DevToolsActivePort file doesn't exist)   (The process started from chrome location /usr/bin/chromium-browser is no longer running, so ChromeDriver is assuming that Chrome has crashed.) Stacktrace:
#0 0x5555f50dc3e4 <unknown>
#1 0x5555f4e11ac8 <unknown>
#2 0x5555f4e40fac <unknown>
#3 0x5555f4e3dc44 <unknown>
#4 0x5555f4e7cf08 <unknown>
#5 0x5555f4e48d74 <unknown>
#6 0x5555f4e49760 <unknown>
#7 0x5555f50a6a74 <unknown>
#8 0x5555f50a9e04 <unknown>
#9 0x5555f5096d7c <unknown>
#10 0x5555f50aa714 <unknown>
#11 0x5555f507f0e0 <unknown>
#12 0x5555f50cbbc4 <unknown>
#13 0x5555f50cbdc0 <unknown>
#14 0x5555f50db5b4 <unknown>
#15 0x7fff46fcee58 <unknown>
#16 0x7fff47037f9c <unknown>

解决步骤 #

1. 配置Selenium无界面运行参数 #

cron运行环境没有图形界面，必须为Chromium添加headless及必要的启动参数，修改脚本中初始化driver的代码：

from selenium import webdriver
from selenium.webdriver.chrome.options import Options
from selenium.webdriver.chrome.service import Service

# 配置Chromium启动选项
options = Options()
options.add_argument('--headless=new')          # 启用新版无界面模式
options.add_argument('--no-sandbox')            # 禁用沙箱，cron环境下必须
options.add_argument('--disable-dev-shm-usage') # 避免/dev/shm内存不足问题
options.add_argument('--remote-debugging-port=9222') # 解决DevToolsActivePort缺失问题
options.binary_location = '/usr/bin/chromium-browser' # 指定Chromium可执行文件路径

# 初始化driver
service = Service(executable_path='/usr/bin/chromedriver')
driver = webdriver.Chrome(service=service, options=options)

2. 完善cron环境变量配置 #

cron默认的环境变量PATH比用户终端少，需手动指定完整路径及shell环境：

1. 执行crontab -e打开定时任务编辑器
2. 添加以下内容（替换为你的脚本路径和执行时间）：

SHELL=/bin/bash
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games
# 示例：每小时执行一次脚本，并输出日志到指定文件
0 */1 * * * /home/dean/main_venv/bin/python3 /home/dean/main_venv/luxpowerdl.py >> /home/dean/cron_script.log 2>&1

• SHELL指定使用bash，避免默认sh导致的环境差异
• PATH包含所有必要的执行路径，确保chromedriver和Python能被找到
• 日志输出便于后续排查问题

3. 补充显示环境变量（可选） #

如果上述步骤仍未解决，可尝试在cron任务中添加DISPLAY=:0：

0 */1 * * * DISPLAY=:0 /home/dean/main_venv/bin/python3 /home/dean/main_venv/luxpowerdl.py >> /home/dean/cron_script.log 2>&1

4. 测试验证 #

• 保存crontab后，手动运行脚本测试是否正常：

/home/dean/main_venv/bin/python3 /home/dean/main_venv/luxpowerdl.py

• 查看日志文件确认执行情况：

cat /home/dean/cron_script.log

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