How can I run Selenium Webdriver using pythonw?
I am trying to open Firefox browser in Selenium script through a graphical application on Windows. It worked just fine while running from python.exe runw.py
, but when I launch it with pythonw.exe runw.py
, the browser cannot launch. Instead, this throws this exception:
Traceback (most recent call last):
File "bin\runw.py", line 215, in process_instance
instance.setup()
File "bin\mixin.py", line 181, in setup
self.browser = self.get_firefox_browser()
File "bin\mixin.py", line 166, in get_firefox_browser
firefox_binary=binary, firefox_profile=profile)
File "C:\myvirtualenv\lib\site-packages\selenium\webdriver\firefox\webdriver.py", line 59, in __init__
self.binary, timeout),
File "C:\myvirtualenv\lib\site-packages\selenium\webdriver\firefox\extension_connection.py", line 47, in __init__
self.binary.launch_browser(self.profile)
File "C:\myvirtualenv\lib\site-packages\selenium\webdriver\firefox\firefox_binary.py", line 60, in launch_browser
self._start_from_profile_path(self.profile.path)
File "C:\myvirtualenv\lib\site-packages\selenium\webdriver\firefox\firefox_binary.py", line 83, in _start_from_profile_path
env=self._firefox_env).communicate()
File "C:\Python27\Lib\subprocess.py", line 702, in __init__
errread, errwrite), to_close = self._get_handles(stdin, stdout, stderr)
File "C:\Python27\Lib\subprocess.py", line 833, in _get_handles
p2cread = self._make_inheritable(p2cread)
File "C:\Python27\Lib\subprocess.py", line 884, in _make_inheritable
_subprocess.DUPLICATE_SAME_ACCESS)
WindowsError: [Error 6] The handle is invalid
The problem, of course, is the lack of stdin
or stdout
(I'm not sure) because in this line the ( firefox_binary.py
) does not work :
def _start_from_profile_path(self, path):
...
Popen(command, stdout=self._log_file, stderr=STDOUT,
env=self._firefox_env).communicate()
command[1] = '-foreground'
self.process = Popen(
command, stdout=self._log_file, stderr=STDOUT,
env=self._firefox_env)
I tried overriding syd.stdout
with the output file before starting the browser, but it didn't work:
sys.stdout = sys.stderr = open('log.txt', 'a+')
I am running Python2.7 and Selenium 2.40. How can Selenium work with pythonw
?
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Like @falsetru, it subprocess
tries to describe the user's file 0
. Calling a subprocess only works if all the descriptors are valid (or all of them None
), and as pythonw
it is a Windows process and it is not, I was forced to subclass to FirefoxBinary
use nul
descriptors:
class WindowsFirefoxBinary(FirefoxBinary):
def _start_from_profile_path(self, path):
self._firefox_env["XRE_PROFILE_PATH"] = path
if platform.system().lower() == 'linux':
self._modify_link_library_path()
command = [self._start_cmd, "-silent"]
if self.command_line is not None:
for cli in self.command_line:
command.append(cli)
# Added stdin argument:
nul = open(os.devnull, 'w+')
Popen(command, stdin=nul, stdout=self._log_file or nul, stderr=STDOUT,
env=self._firefox_env).communicate()
command[1] = '-foreground'
self.process = Popen(
command, stdin=nul, stdout=self._log_file or nul, stderr=STDOUT,
env=self._firefox_env)
This way I can use my own binary when instantiating the WebDriver:
binary = WindowsFirefoxBinary()
browser = webdriver.Firefox(firefox_binary=binary)
This could be a bug or just an incompatibility in Selenium with Python for Windows.
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