Timeout exception while waiting for webpage with element in headless chrome

问题

Following code uses non-headless chrome and it works:

import os
from selenium import webdriver
from selenium.webdriver.common.keys import Keys
from selenium.webdriver.chrome.options import Options
from selenium.webdriver.common.by import By
from selenium.webdriver.support import expected_conditions as EC
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait


chrome_options = Options()
chrome_options.add_argument("--headless")
chrome_options.add_argument('--start-maximized')
chrome_options.binary_location = 'C:\Program Files (x86)\Google\Chrome\Application\chrome.exe'

driver = webdriver.Chrome(executable_path=os.path.abspath("C:\User\Program Files\chrome-driver\chromedriver.exe"))

driver.set_window_size(1200, 600) 

driver.get("login-url")
driver.find_element_by_id("loginId").send_keys("uname")
driver.find_element_by_id("newPassword").send_keys("pwd")
driver.find_element_by_name("submit-button").click()
driver.set_window_size(1200, 800)
WebDriverWait(driver, 10).until(EC.visibility_of_element_located((By.ID,"user-info")))

v = driver.find_element_by_xpath("//tr[4]/td[5]/span").text

print(v)

When I choose to use headless chrome:

driver = webdriver.Chrome(executable_path=os.path.abspath("C:\User\Program Files\chrome-driver\chromedriver.exe"), chrome_options=chrome_options)

It throws following exception:

Traceback (most recent call last):
  File "C:/User/workspaces/pyworkspaces/fin2/venv/process.py", line 28, in <module>
    WebDriverWait(driver, 10).until(EC.visibility_of_element_located((By.ID,"user-info")))
  File "C:\User\workspaces\pyworkspaces\fin2\venv\lib\site-packages\selenium\webdriver\support\wait.py", line 80, in until
    raise TimeoutException(message, screen, stacktrace)
selenium.common.exceptions.TimeoutException: Message: 

So it seems to fail on following line, in headless chrome:

WebDriverWait(driver, 10).until(EC.visibility_of_element_located((By.ID,"user-info")))

I also tried presence_of_element_located:

WebDriverWait(driver, 10).until(EC.presence_of_element_located((By.ID,"user-info")))

But it still gives TimeOutException. Why is it so?

回答1:

What I did in the past is adding the argument '--start-maximized':

chrome_options.add_argument('--start-maximized')

Try it hope it helps you!

回答2:

Instead of using presence_of_element_located() you need to wait for visibility_of_element_located() and you can use the following Locator Strategy:

• Using ID:

  element = WebDriverWait(driver, 10).until(EC.visibility_of_element_located((By.ID,"user-info")))
  

• Using CSS_SELECTOR:

  element = WebDriverWait(driver, 20).until(EC.visibility_of_element_located((By.CSS_SELECTOR, "#user-info")))
  

• Using XPATH:

  element = WebDriverWait(driver, 20).until(EC.visibility_of_element_located((By.XPATH, "//*[@id='user-info']")))
  

• Note : You have to add the following imports :

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

来源：https://stackoverflow.com/questions/56682149/timeout-exception-while-waiting-for-webpage-with-element-in-headless-chrome