Selenium 与 chromedriver 根据“无头”参数给出不同的结果

我一直在使用 Selenium + Chromedriver，我注意到根据是否启用或禁用 headless，我得到了不同的结果。经过一番调查，我发现“无头”不包括Accept-Language header.

有没有办法手动将其添加到标题中？

理想情况下，使用和不使用--headless选项不应对其中的元素产生任何重大影响DOM Tree https://javascript.info/dom-nodes得到渲染，但可能有显着差异Viewport https://www.w3schools.com/css/css_rwd_viewport.asp被关注到。

例如，当 ChromeDriver/Chrome 与--headless选项默认Viewport is

width = 800px, height = 600px 

当 ChromeDriver/Chrome 初始化时没有--headless选项默认Viewport is:

width = 1050px, height = 708px

• 示例代码（基于Python):

  from selenium import webdriver
  from selenium.webdriver.common.by import By
  from selenium.webdriver.support.ui import WebDriverWait
  from selenium.webdriver.support import expected_conditions as EC
  
  options = webdriver.ChromeOptions()
  options.add_argument("--headless")
  options.add_experimental_option("excludeSwitches", ["enable-automation"])
  options.add_experimental_option('useAutomationExtension', False)
  driver = webdriver.Chrome(options=options, executable_path=r'C:\Utility\BrowserDrivers\chromedriver.exe')
  driver.get("https://www.google.com/")
  WebDriverWait(driver, 10).until(EC.element_to_be_clickable((By.NAME, "q")))
  print ("Headless Chrome Initialized")
  size = driver.get_window_size()
  print("Window size: width = {}px, height = {}px".format(size["width"], size["height"]))
  driver.quit()
  options = webdriver.ChromeOptions()
  options.add_experimental_option("excludeSwitches", ["enable-automation"])
  options.add_experimental_option('useAutomationExtension', False)
  driver = webdriver.Chrome(options=options, executable_path=r'C:\Utility\BrowserDrivers\chromedriver.exe')
  driver.get("https://www.google.com/")
  WebDriverWait(driver, 10).until(EC.element_to_be_clickable((By.NAME, "q")))
  print ("Chrome Initialized")
  size = driver.get_window_size()
  print("Window size: width = {}px, height = {}px".format(size["width"], size["height"]))
  

• 控制台输出：

  Headless Chrome Initialized
  Window size: width = 800px, height = 600px
  Chrome Initialized
  Window size: width = 1050px, height = 708px
  

所以可以得出结论--headless选项 ChromeDriver/Chrome 打开会话，减少Viewport因此识别出的元素数量较少。

Solution

使用 ChromeDriver/Chrome 启动浏览实例始终打开于maximized mode:

from selenium import webdriver
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.common.by import By
from selenium.webdriver.support import expected_conditions as EC

options = webdriver.ChromeOptions()
options.add_argument("start-maximized")
options.add_argument("--headless")
options.add_experimental_option("excludeSwitches", ["enable-automation"])
options.add_experimental_option('useAutomationExtension', False)
driver = webdriver.Chrome(options=options, executable_path=r'C:\Utility\BrowserDrivers\chromedriver.exe')
driver.get("https://www.google.com/")