selenium调用chrome浏览器报错解决方式：unknown error: DevToolsActivePort file doesn‘t exist

具体报错如下：

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/project/login_by_user.py", line 175, in open_client
    driver = webdriver.Chrome(const.driver_path_80, chrome_options=chrome_options)
  File "/usr/local/lib/python3.6/site-packages/selenium/webdriver/chrome/webdriver.py", line 81, in __init__
    desired_capabilities=desired_capabilities)
  File "/usr/local/lib/python3.6/site-packages/selenium/webdriver/remote/webdriver.py", line 157, in __init__
    self.start_session(capabilities, browser_profile)
  File "/usr/local/lib/python3.6/site-packages/selenium/webdriver/remote/webdriver.py", line 252, in start_session
    response = self.execute(Command.NEW_SESSION, parameters)
  File "/usr/local/lib/python3.6/site-packages/selenium/webdriver/remote/webdriver.py", line 321, in execute
    self.error_handler.check_response(response)
  File "/usr/local/lib/python3.6/site-packages/selenium/webdriver/remote/errorhandler.py", line 242, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.WebDriverException: Message: unknown error: Chrome failed to start: exited abnormally.
  (unknown error: DevToolsActivePort file doesn't exist)
  (The process started from chrome location /usr/bin/google-chrome is no longer running, so ChromeDriver is assuming that Chrome has crashed.)

1. 原因1：

   chromedriver的版本与google-chrome版本不一致

  查看方式：chromedriver --version 和  google-chrome --version 要是版本不一致引起的问题，可以重新安装成匹配的版本。

  安装示例：

（1）先安装 google-chrome

#下载
wget https://dl.google.com/linux/direct/google-chrome-stable_current_x86_64.rpm

#安装
yum install -y google-chrome-stable_current_x86_64.rpm

#查看版本号
google-chrome --version

（2）再安装chromedriver：一定要先查看google-chrome版本号，安装匹配的版本（最好是版本号一模一样），chromedriver版本查找页面：http://chromedriver.storage.googleapis.com/index.html，找到合适的版本号

#通过上面链接，找到合适的版本下载
wget http://chromedriver.storage.googleapis.com/90.0.4430.24/chromedriver_linux64.zip

#解压
unzip chromedriver_linux64.zip

#移动到启动路径
mv chromedriver /usr/local/bin/

#分配权限
chmod 777 /usr/local/bin/chromedriver

#查看版本号
chromedriver --version

（3）安装selenium，由于Selenium是标准的python包，这里直接基于pip进行安装。

pip install selenium

2. 原因2： Chrome启动参数未添加完整，我就是因为第二行--headless被注释掉而报错，排查了好久，所以以下几行配置参数必不可少。 完整的参数如下：

 chrome_options = webdriver.ChromeOptions()
 chrome_options.add_argument('--headless')
 chrome_options.add_argument('--no-sandbox')
 chrome_options.add_argument('--disable-gpu')
 chrome_options.add_argument('--disable-dev-shm-usage')

至此，就完成了chrome的驱动安装了。

参考链接：CentOS上安装Selenium和google Driver的过程以及问题记录

chromedriver版本号对应链接

Centos之Chrome浏览器安装-yellowcong