最近基于selenium写了一个python小工具,记录下学习记录,自己运行的环境是Ubuntu 14.04.4, Python 2.7,Chromium 49.0,ChromeDriver 2.16

selenium简介

selenium提供了一个通用的接口,可模拟用户来操作浏览器,比如用于自动化测试等.
selenium的核心是WebDriver,它提供了一组接口,这些接口能够操作各种跨平台的浏览器.
各大浏览器厂商.

各大浏览器厂商也支持Selenium,将其作为浏览器的一部分.

selenium工具集提供了WebDriver,Selenium IDE,Selenium-Grid等

Selenium 1.0 + WebDriver = Selenium 2.0

Selenium WebDriver是Selenium Remote Control(Selenium-RC)的继承者.

• WebDriver提供了更简单和简洁的接口,克服了Selenium-RC API一些限制.
• 相比Selenium 1.0,WebDriver是面向对象式的服务.
• WebDriver驱动浏览器更有效率,提供了比Selenium 1.0更多的功能
• Selenium RC只能在单机上运行,WebDriver则提供了远程操作的功能

selenium基本使用

selenium运行需要什么

主要包括三部分:selenium selenium,浏览器driver,浏览器。

selenium selenium是一组通用的接口,而不同的浏览器提供其自身的driver(大部分是官方的),浏览器则被模拟控制操作的终端.

安装

pip install selenium --upgrade
apt-get install chromium-browser
wget http://chromedriver.storage.googleapis.com/2.10/chromedriver_linux`getconf LONG_BIT`.zip
unzip chromedriver_linux32.zip
cp chromedriver /usr/local/share
chmod +x /usr/local/share/chromedriver
ln -s /usr/local/share/chromedriver /usr/local/bin/chromedriver 
ln -s /usr/bin/chromedriver /usr/local/share/chromedriver 

简单的使用

from selenium import webdriver
driver = webdriver.Chrome('/usr/local/bin/chromedriver')
driver.get('http://mail.sina.net');
print(driver.title)

API使用

可参考/usr/local/lib/python2.7/dist-packages/selenium

Chrome WebDriver

selenium.webdriver.chrome.webdriver.WebDriver(executable_path='chromedriver', port=0, chrome_options=None, service_args=None, desired_capabilities=None, service_log_path=None)

ChromeOptions

可以通过ChromeDriver session配置ChromeDriver session
ChromeDriverconvenient methods for setting ChromeDriver-specific capabilities

from selenium.webdriver.chrome.options import Options
chrome_options = Options()
chrome_options.add_argument("--disable-extensions")
chrome_options.add_argument('--disable-logging')
chrome_options.add_experimental_option('prefs', {'download.default_directory':
'/tmp'})
chrome_options.binary_location='/usr/bin/chromium-browser'
driver = webdriver.Chrome(chrome_options=chrome_options)

直接使用DesiredCapabilities

ChromeOptions是构建在DesiredCapabilities之上的,为了使用DesiredCapabilities,必须
知道capability的Key/value对.

chrome_options = Options()
capabilities={}
capabilities['platform'] = "WINDOWS"
capabilities['version'] = "10"
capabilities.update(chrome_options.to_capabilities())
driver = webdriver.Chrome(desired_capabilities=capabilities)

chromedriver运行方式

The ChromeDriver class不断的创建实例,会浪费很多的时间,可以通过两个方式解决.

使用ChromeDriverService

import selenium.webdriver.chrome.service as service
service = service.Service('/usr/bin/chromedrive')
service.start()
capabilities = { }
driver = webdriver.Remote(service.service_url, capabilities)
driver.get('http://mail.sina.net');
print(driver.title)

开启单独的ChromeDriver服务

./chromedriver

driver = webdriver.Remote('http://127.0.0.1:9515', DesiredCapabilities.CHROME)
driver.get('http://mail.sina.net');

RemoteWebDriverServer

The RemoteWebDriver is composed of two pieces: a client and a server. The client is your WebDriver test and the server is simply a Java servlet, which can be hosted in any modern JEE app server. The server will always run on the machine with the browser you want to test.

wget http://selenium-release.storage.googleapis.com/2.53/selenium-server-standalone-2.53.0.jar
java -jar selenium-server-standalone-2.53.0.jar

from selenium import webdriver
from selenium.webdriver.common.desired_capabilities import DesiredCapabilities
driver = webdriver.Remote( command_executor='http://127.0.0.1:4444/wd/hub',des
desired_capabilities=DesiredCapabilities.CHROME)
driver.get('http://mail.sina.net');

其他

参考网站:

• 官方网站,官方github
• ChromeDriver
• Python api
• Selenium非官方文档

used pyvirtualdisplay to simulate a display:
由于使用的是Ubuntu服务器版,所以无法运行chrome,通过pyvirtualdisplay解决该问题

sudo apt-get install Xvfb
sudo pip install pyvirtualdisplay

from pyvirtualdisplay import Display
display = Display(visible=0, size=(1024, 768))
display.start()
driver = webdriver.Chrome('/usr/local/bin/chromedriver')
driver.get('http://mail.sina.net');
print(driver.title)
display.stop()

Explicit Wait:
由于是模拟用户操作浏览器,浏览器加载需要时间,为确保成功加载完成才继续执行下去,解决方案如下

from selenium.webdriver.support.ui import WebDriverWait
driver = webdriver.Chrome()
driver.get('http://mail.sina.net/login');
el =  WebDriverWait(driver, 10).until(lambda x: x.find_element_by_id("loginfromemail"))
print(el.text)