python - Selenium "Unable to find a matching set of capabilities"尽管驱动程序位于/usr/local/bin

Question

我正在尝试学习有关 Selenium 的教程，http://selenium-python.readthedocs.io/getting-started.html .我已经下载了最新版本的 geckodriver 并将其复制到 /usr/local/bin。但是，当我尝试

from selenium import webdriver
driver = webdriver.Firefox()

我收到以下错误消息:

Traceback (most recent call last):
  File "/Users/kurtpeek/Documents/Scratch/selenium_getting_started.py", line 4, in <module>
    driver = webdriver.Firefox()
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/selenium/webdriver/firefox/webdriver.py", line 152, in __init__
    keep_alive=True)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/selenium/webdriver/remote/webdriver.py", line 98, in __init__
    self.start_session(desired_capabilities, browser_profile)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/selenium/webdriver/remote/webdriver.py", line 188, in start_session
    response = self.execute(Command.NEW_SESSION, parameters)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/selenium/webdriver/remote/webdriver.py", line 252, in execute
    self.error_handler.check_response(response)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/selenium/webdriver/remote/errorhandler.py", line 194, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.WebDriverException: Message: Unable to find a matching set of capabilities

[Finished in 1.2s with exit code 1]

来自 https://github.com/SeleniumHQ/selenium/issues/3884 ，似乎其他用户也遇到了类似的问题，但 Selenium 团队无法重现它。如何让 Selenium 与 Firefox 一起工作？ (它确实适用于 chromedriver 和一个 webdriver.Chrome() 实例，所以我怀疑这可能是 Selenium 中的一个错误。

Answer 1

更新 Firefox 和 Selenium 为我解决了这个问题。但是，我不会假装对根本原因有解释。

• 更新 Firefox 48 → 53
• 更新到 Selenium 3.4.1

我还使用 Homebrew 重新安装/更新了 Geckodriver 并明确将其用作 Selenium WebDriver 的可执行文件，但事实证明它不是没有必要减轻 “无法找到匹配的功能集” 错误。