更改 Selenium Web 驱动程序的用户代理

我在 Python中有以下代码:

from selenium.webdriver import Firefox
from contextlib import closing


with closing(Firefox()) as browser:
browser.get(url)

我想打印用户代理 HTTP 标头和 有可能改变它,有可能吗?

194226 次浏览

There is no way in Selenium to read the request or response headers. You could do it by instructing your browser to connect through a proxy that records this kind of information.

Setting the User Agent in Firefox

The usual way to change the user agent for Firefox is to set the variable "general.useragent.override" in your Firefox profile. Note that this is independent from Selenium.

You can direct Selenium to use a profile different from the default one, like this:

from selenium import webdriver
profile = webdriver.FirefoxProfile()
profile.set_preference("general.useragent.override", "whatever you want")
driver = webdriver.Firefox(profile)

Setting the User Agent in Chrome

With Chrome, what you want to do is use the user-agent command line option. Again, this is not a Selenium thing. You can invoke Chrome at the command line with chrome --user-agent=foo to set the agent to the value foo.

With Selenium you set it like this:

from selenium import webdriver
from selenium.webdriver.chrome.options import Options
opts = Options()
opts.add_argument("user-agent=whatever you want")


driver = webdriver.Chrome(chrome_options=opts)

Both methods above were tested and found to work. I don't know about other browsers.

Getting the User Agent

Selenium does not have methods to query the user agent from an instance of WebDriver. Even in the case of Firefox, you cannot discover the default user agent by checking what general.useragent.override would be if not set to a custom value. (This setting does not exist before it is set to some value.)

Once the browser is started, however, you can get the user agent by executing:

agent = driver.execute_script("return navigator.userAgent")

The agent variable will contain the user agent.

To build on Louis's helpful answer...

Setting the User Agent in PhantomJS

from selenium import webdriver
from selenium.webdriver.common.desired_capabilities import DesiredCapabilities
...
caps = DesiredCapabilities.PHANTOMJS
caps["phantomjs.page.settings.userAgent"] = "whatever you want"
driver = webdriver.PhantomJS(desired_capabilities=caps)

The only minor issue is that, unlike for Firefox and Chrome, this does not return your custom setting:

driver.execute_script("return navigator.userAgent")

So, if anyone figures out how to do that in PhantomJS, please edit my answer or add a comment below! Cheers.

To build on JJC's helpful answer that builds on Louis's helpful answer...

With PhantomJS 2.1.1-windows this line works:

driver.execute_script("return navigator.userAgent")

If it doesn't work, you can still get the user agent via the log (to build on Mma's answer):

from selenium import webdriver
import json
from fake_useragent import UserAgent


dcap = dict(DesiredCapabilities.PHANTOMJS)
dcap["phantomjs.page.settings.userAgent"] = (UserAgent().random)
driver = webdriver.PhantomJS(executable_path=r"your_path", desired_capabilities=dcap)
har = json.loads(driver.get_log('har')[0]['message']) # get the log
print('user agent: ', har['log']['entries'][0]['request']['headers'][1]['value'])

This is a short solution to change the request UserAgent on the fly.

Change UserAgent of a request with Chrome

from selenium import webdriver
from selenium.webdriver.common.desired_capabilities import DesiredCapabilities


driver = webdriver.Chrome(driver_path)
driver.execute_cdp_cmd('Network.setUserAgentOverride', {"userAgent":"python 2.7", "platform":"Windows"})
driver.get('http://amiunique.org')

then return your useragent:

agent = driver.execute_script("return navigator.userAgent")

Some sources

The source code of webdriver.py from SeleniumHQ (https://github.com/SeleniumHQ/selenium/blob/11c25d75bd7ed22e6172d6a2a795a1d195fb0875/py/selenium/webdriver/chrome/webdriver.py) extends its functionalities through the Chrome Devtools Protocol

def execute_cdp_cmd(self, cmd, cmd_args):
"""
Execute Chrome Devtools Protocol command and get returned result

We can use the Chrome Devtools Protocol Viewer to list more extended functionalities (https://chromedevtools.github.io/devtools-protocol/tot/Network#method-setUserAgentOverride) as well as the parameters type to use.

Firefox Profile is deprecated, you have to use it in Firefox options like this:

opts = FirefoxOptions()
opts.add_argument("--headless")
opts.add_argument("--width=800")
opts.add_argument("--height=600")
opts.set_preference("general.useragent.override", "userAgent=Mozilla/5.0
(iPhone; CPU iPhone OS 15_4 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like
Gecko) CriOS/101.0.4951.44 Mobile/15E148 Safari/604.1")