Pycharm：使用Python的Selenium：無法使用無頭Chrome瀏覽器查找Web元素

Question

當我使用無頭的chrome瀏覽器運行以下代碼時，在識別元素時遇到了問題。 通過以head full模式注釋以下各行，可以運行相同的代碼。

＃chrome_options.add_argument（'-headless'）

＃chrome_options.add_argument（'-disable-gpu'）

測試詳情：

作業系統： Windows10

ChromeDriver： 75.0.3770.8

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

chrome_options = webdriver.ChromeOptions()
chrome_options.add_argument('--headless')
chrome_options.add_argument('--disable-gpu')
driver = webdriver.Chrome(ChromeDriverManager().install(), options=chrome_options)
wait = WebDriverWait(driver,30)
driver.maximize_window()
driver.get('https://learn.letskodeit.com/')
print(driver.title)
wait.until(EC.element_to_be_clickable((By.LINK_TEXT, 'Login'))).click()
wait.until(EC.visibility_of_element_located((By.ID, 'user_email'))).send_keys("test@email.com")
wait.until(EC.visibility_of_element_located((By.ID, 'user_password'))).send_keys("abcabc")
wait.until(EC.visibility_of_element_located((By.NAME, 'commit'))).click()
print(driver.title)
driver.close()
driver.quit()

輸出：

"C:\Program Files (x86)\Python37-32\python.exe" C:/PycharmProjects/seleniumwd2/basics/RunHeadlessChromeTests.py

Checking for win32 chromedriver:75.0.3770.8 in cache
Driver found in C:\Users\vishr\.wdm\chromedriver\75.0.3770.8\win32/chromedriver.exe
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Traceback (most recent call last):
  File "C:/PycharmProjects/seleniumwd2/basics/RunHeadlessChromeTests.py", line 15, in <module>
    wait.until(EC.element_to_be_clickable((By.LINK_TEXT, 'Login'))).click()
  File "C:\Users\vishr\AppData\Roaming\Python\Python37\site-packages\selenium\webdriver\support\wait.py", line 80, in until
    raise TimeoutException(message, screen, stacktrace)
selenium.common.exceptions.TimeoutException: Message: 


Process finished with exit code 1

Answer 1

對於無頭瀏覽器，您必須將窗口大小設置為在事件時觸發。因為無頭瀏覽器無法識別沒有窗口大小的點擊位置。

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

chrome_options = webdriver.ChromeOptions()
chrome_options.add_argument('--headless')
chrome_options.add_argument('--disable-gpu')
chrome_options.add_argument('window-size=1920x1080')

driver = webdriver.Chrome(executable_path='path/to/chrome driver',options=chrome_options)
wait = WebDriverWait(driver,30)
driver.maximize_window()
driver.get('https://learn.letskodeit.com/')
print(driver.title)
wait.until(EC.element_to_be_clickable((By.LINK_TEXT, 'Login'))).click()
wait.until(EC.visibility_of_element_located((By.ID, 'user_email'))).send_keys("test@email.com")
wait.until(EC.visibility_of_element_located((By.ID, 'user_password'))).send_keys("abcabc")
wait.until(EC.visibility_of_element_located((By.NAME, 'commit'))).click()
print(driver.title)
driver.close()
driver.quit()

在無頭模式下在控制台上打印輸出。

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Answer 2

您正在單擊一個加載另一個頁面的按鈕。 您必須等待其他頁面加載。 要做到完美，這很棘手。

最簡單的解決方案：

sleep(3)

使用隱式等待的更好解決方案：

driver.implicitly_wait(3)

使用顯式等待的更好解決方案：

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

WebDriverWait(driver, 3).until(EC.presence_of_element_located((By.ID, "user_email")))

更好的解決方案是捕獲異常，並將所有這些解決方案分層。

Answer 3

VISHVAMBRUTHJAVAGALTHIMMEGOWDA，

我嘗試了您的代碼，並遇到了相同的異常，首先，我認為用戶名位於Frame或iframe中，但不是。

然后我嘗試介紹webdriver wait，它工作得很好：

代碼：

wait = WebDriverWait(driver,10)

driver.maximize_window()

driver.get("https://learn.letskodeit.com/")

print(driver.title)

driver.find_element_by_xpath("//a[contains(text(),'Login')]").click()

wait.until(EC.visibility_of_element_located((By.ID, 'user_email'))).send_keys("test@email.com")

#driver.find_element_by_id("user_email").

driver.find_element_by_id("user_password").send_keys("abcabc")

driver.find_element_by_name("commit").click()

print(driver.title)  

記住要導入這些：

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

編輯1：

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

options = Options()
options.add_argument('--headless')
options.add_argument('--disable-gpu')  # Last I checked this was necessary.
driver = webdriver.Chrome("C:/Users/XXXX/Downloads/BrowserDriver/chromedriver_win32/chromedriver.exe", chrome_options=options)
wait = WebDriverWait(driver,10)

driver.get("https://learn.letskodeit.com/")

print(driver.title)


wait.until(EC.element_to_be_clickable((By.LINK_TEXT, 'Login'))).click()

wait.until(EC.visibility_of_element_located((By.ID, 'user_email'))).send_keys("test@email.com")

wait.until(EC.visibility_of_element_located((By.ID, 'user_password'))).send_keys("abcabc")

wait.until(EC.visibility_of_element_located((By.NAME, 'commit'))).click()

print(driver.title)

Answer 4

要在文本為Login的元素上click() ，必須為element_to_be_clickable()誘導WebDriverWait ，並且可以使用以下任一解決方案：

• 使用PARTIAL_LINK_TEXT ：

   WebDriverWait(driver, 20).until(EC.element_to_be_clickable((By.PARTIAL_LINK_TEXT, "Login"))).click() 

• 使用CSS_SELECTOR ：

   WebDriverWait(driver, 20).until(EC.element_to_be_clickable((By.CSS_SELECTOR, "a.navbar-link.fedora-navbar-link[href='/sign_in']"))).click() 

• 使用XPATH ：

   WebDriverWait(driver, 20).until(EC.element_to_be_clickable((By.XPATH, "//a[@class='navbar-link fedora-navbar-link' and @href='/sign_in']"))).click() 

• 注意 ：您必須添加以下導入：

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