python2和python3共存,Selenium错误的处理

更新Centos源

wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

或者

curl -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

#下载完后,运行下面命令:

yum clean all

yum makecache

1.Python3安装与python2共存

wget http://mirrors.sohu.com/python/3.6.2/Python-3.6.2.tar.xz
 
yum install libffi-devel expat-devel gdbm-devel zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel gcc make
 
mv /usr/bin/python /usr/bin/python.bak
 
tar -xvJf  Python-3.6.2.tar.xz
 
cd Python-3.6.2
 
./configure prefix=/usr/local/python3
 
make && make install
 
make clean
 
ln -s /usr/local/python3/bin/python3 /usr/bin/python

python -V 检查下是不是python3

python2 -V 检查下是不是python2

如果上面正常显示,请继续设置下。yum需要python2版本，所以我们还要修改yum的配置。/usr/libexec/urlgrabber-ext-down也需要修改python2

vi /usr/bin/yum

#把文件第一行python改成python2

#!/usr/bin/python2                                                                          
import sys                                                                                 
try:                                                                                       
    import yum                                                                              
except ImportError:

......继续修改urlgrabber-ext-down

vi /usr/libexec/urlgrabber-ext-down

#跟上面一样修改第一行python改成python2

#! /usr/bin/python2                                                                        

#  A very simple external downloader                                                        

#  Copyright 2011-2012 Zdenek Pavlas

hon2和python3共存:默认pip是python2,python3需要如何配置？如果pip也没有安装,就先安装pip

yum -y install epel-release
yum install python-pip
ln -s /usr/local/python3/bin/pip3 /usr/bin/pip3

配置pip源按自己需要,也可以不配置

mkdir ~/.pip
 
vi pip.conf
 
 
[global]
 
timeout = 60
 
index-url = https://pypi.doubanio.com/simple

test.py测试代码如下:chrome界面浏览

# -*- coding:utf-8 -*-
 
 
from selenium import webdriver
 
 
options = webdriver.ChromeOptions()
 
options.add_argument('--headless')
 
options.add_argument('--disable-gpu')
 
driver = webdriver.Chrome(executable_path="/root/test/chromedriver", chrome_options=options)
 
driver.get("https://www.baidu.com")
 
print(driver.page_source)
 
driver.quit()

测试运行看看

python test.py

运行完果断报错

raise exception_class(message, screen, stacktrace)

selenium.common.exceptions.WebDriverException: Message: unknown error: DevToolsActivePort file doesn't exist

修改test.py加上–no-sandbox完美解决。当然使用selenium可能会出现其他的错误，我会在其他文章收集些错误解决办法。

# -*- coding:utf-8 -*-
 
 
 
from selenium import webdriver
 
 
 
options = webdriver.ChromeOptions()
 
options.add_argument('--headless')
 
options.add_argument('--disable-gpu')
 
options.add_argument('--no-sandbox')
 
driver = webdriver.Chrome(executable_path="/root/test/chromedriver", chrome_options=options)
 
driver.get("https://www.baidu.com")
 
print(driver.page_source)
 
driver.quit()