python selenium模块使用出错-selenium.common.exceptions.WebDriverException: Message: 'geckodriver' executable needs to be in PATH.

Python 2.7+selenium+Firefox 55.0.3

代码：

from selenium import webdriver
from selenium.common.exceptions import NoSuchElementException
from selenium.webdriver.common.keys import Keys
import time

browser = webdriver.Firefox() # Get local session of firefox
browser.get("http://www.yahoo.com") # Load page
assert "Yahoo!" in browser.title
elem = browser.find_element_by_name("p") # Find the query box
elem.send_keys("seleniumhq" + Keys.RETURN)
time.sleep(0.2) # Let the page load, will be added to the API
try:
    browser.find_element_by_xpath("//a[contains(@href,'http://seleniumhq.org')]")
except NoSuchElementException:
    assert 0, "can't find seleniumhq"
browser.close()

错误信息如下:

selenium.common.exceptions.WebDriverException: Message: 'geckodriver' executable needs to be in PATH.

回答摘自知乎：https://www.zhihu.com/question/49568096

1. selenium 3.x开始，webdriver/firefox/webdriver.py的__init__中，executable_path="geckodriver"；而2.x是executable_path="wires"
2. firefox 47以上版本，需要下载第三方driver，即geckodriver；在http://docs.seleniumhq.org/download/的Third Party Drivers, Bindings, and Plugins下面找到Mozilla GeckoDriver，下载到任意电脑任意目录(Mac 下放到了/usr/bin/ 和/sbin/, /bin/，/usr/local/bin/)，解压后将该路径加入到PC的path（针对windows）即可。

作者：iceblue iceblue
链接：https://www.zhihu.com/question/49568096/answer/119324584
来源：知乎
著作权归作者所有。商业转载请联系作者获得授权，非商业转载请注明出处。