问题
I start a display with pyvirtualdisplay
before creating my WebDriver
instance. If I use Chrome, it works without any problem: Chrome shows up in the Xephyr instance that pyvirtualdisplay
creates. However, when I use Firefox, the Xephyr instance appears but Firefox shows up outside of it.
Here is code that fully reproduces the problem:
from selenium import webdriver
from selenium.webdriver.firefox.webdriver import FirefoxBinary
import pyvirtualdisplay
binary = FirefoxBinary()
with pyvirtualdisplay.Display(visible=True):
if True: # Set to False to use Chrome...
driver = webdriver.Firefox(None, binary)
else:
driver = webdriver.Chrome()
driver.get("http://www.google.com")
driver.quit()
The code above is a minimal version of code that is more complex (which explains the seemingly useless FirefoxBinary()
).
回答1:
Solution
Move your creation of the FirefoxBinary
object inside the context managed by pyvirtualdisplay.Display
:
from selenium import webdriver
from selenium.webdriver.firefox.webdriver import FirefoxBinary
import pyvirtualdisplay
with pyvirtualdisplay.Display(visible=True):
if True: # Set to False to use Chrome...
binary = FirefoxBinary()
driver = webdriver.Firefox(None, binary)
else:
driver = webdriver.Chrome()
driver.get("http://www.google.com")
driver.quit()
Explanation
The problem is what happens behind the scenes. The environment variable named DISPLAY
is what determines where Firefox and Chrome will connect to. It is not set in the way you'd expect it to be set.
Here is what happens with your code:
You create an instance of
FirefoxBinary
. If you read the source code, you'll see that when an object of this class is created it makes a copy ofos.environ
(the environment).You create a display with
pyvirtualdisplay.Display
and use it as a context manager. As you enter the context, the display altersos.environ
so that as long as the context is in effect, theDISPLAY
environment variable is set so that X clients will connect to the new display instead of whatDISPLAY
was before the context came into effect.You create your driver. When you use Chrome, everything is fine because Chrome will get its
DISPLAY
variable from the modified environment. However, when you use Firefox, it will use theDISPLAY
environment from the environment that was copied in the first step. This environment contains a value ofDISPLAY
which is prior to the alteration described in the previous step, so it does not connect to the new display you created.
来源:https://stackoverflow.com/questions/27202131/firefox-started-by-selenium-ignores-the-display-created-by-pyvirtualdisplay