按字段名从 table 中提取数据。 Xpath，python

Question

我想从此页面中提取数据https://mbasic.facebook.com/kristina.layus 有一个 table“住过的地方”有两行

Current city --- Moscow, Russia
Home town    --- Saint Petersburg, Russia

我可以借助完整的 xpath 提取数据（提取的数据“俄罗斯莫斯科”）：

/html/body/div/div/div[2]/div/div[1]/div[4]/div/div/div[1]/div/table/tbody/tr/td[2]/div/a

但我想借助 table 中的名称提取数据。我试过这个

//div[@id='living']//div[@title='Current City']//a/text()

但是收到错误

NoSuchElementException: Message: no such element: Unable to locate element: {"method":"xpath","selector":"//div[@id='living']//div[@title='Current City']//a/text()"}
  (Session info: chrome=84.0.4147.89)

我的代码

from selenium import webdriver
from selenium.common.exceptions import TimeoutException
from selenium.webdriver.common.by import By
from selenium.webdriver.support.wait import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

class FacebookParser:
    LOGIN_URL = 'https://www.facebook.com/login.php'

    def __init__(self, login, password):
        chrome_options = webdriver.ChromeOptions()
        prefs = {"profile.default_content_setting_values.notifications": 2}
        chrome_options.add_experimental_option("prefs", prefs)

        self.driver = webdriver.Chrome(chrome_options=chrome_options)
        self.wait = WebDriverWait(self.driver, 10)
        self.login(login, password)

    def login(self, login, password):
        self.driver.get(self.LOGIN_URL)

        # wait for the login page to load
        self.wait.until(EC.visibility_of_element_located((By.ID, "email")))

        self.driver.find_element_by_id('email').send_keys(login)
        self.driver.find_element_by_id('pass').send_keys(password)
        self.driver.find_element_by_id('loginbutton').click()
    
    def get_user_by_id(self, id):
        self.driver.get(BASIC_URL + 'profile.php?id=' + str(id))
        
    def get_user_by_url(self, url):
        self.driver.get(url)
    
    def find_element_by_xpath_safe(self, path):
        try:
            return parser.driver.find_element_by_xpath(path)
        except:
            return None

    def get_first_name(self):
        res = self.find_element_by_xpath_safe('//span/div/span/strong')
        if res:
            vec = res.text.split()
            if len(vec) > 0:
                return vec[0]
            else:
                print("Can't split {}".format(res.text))
        return ""

    def get_second_name(self):
        res = self.find_element_by_xpath_safe('//span/div/span/strong')
        if res:
            vec = res.text.split()
            if len(vec) > 1:
                return vec[1]
            else:
                print("Can't split {}".format(res.text))
        return ""
    
    def get_curr_city(self):
        res = self.find_element_by_xpath_safe('/html/body/div/div/div[2]/div/div[1]/div[4]/div/div/div[1]/div/table/tbody/tr/td[2]/div/a')
        if res:
            return res.text
        return ""
    
    def get_home_town(self):
        res = self.find_element_by_xpath_safe('/html/body/div/div/div[2]/div/div[1]/div[4]/div/div/div[2]/div/table/tbody/tr/td[2]/div/a')
        if res:
            return res.text
        return ""
        

#####################################
LOGIN = '----.com'
PASSWORD = '----'
BASIC_URL = 'https://mbasic.facebook.com/'
#####################################

parser = FacebookParser(login=LOGIN, password=PASSWORD)
parser.driver.get("https://mbasic.facebook.com/kristina.layus")


parser.driver.get("https://mbasic.facebook.com/kristina.layus")
print(parser.get_curr_city())

Answer 1

尝试在登录（loginbutton.click()）和打开目标页面之间添加以下代码：

from selenium.webdriver.support import expected_conditions as EC
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
WebDriverWait(wd, DELAY).until(EC.presence_of_element_located((By.ID, "mount_0_0")))

此代码将等到登录过程完成，只有在目标页面打开之后。

同时检查您的 xpath 表达式：在调查页面源代码时，可以找到具有 id="living" 的 div 元素，但是不存在具有属性 title="Current City" 的 div。

Answer 2

要打印文本 Moscow, Russia 你需要诱导 for the visibility_of_element_located() and you can use the following xpath based :

打印俄罗斯莫斯科:

driver.get('https://mbasic.facebook.com/kristina.layus')
print(WebDriverWait(driver, 20).until(EC.visibility_of_element_located((By.XPATH, "//span[text()='Current City']//following::td//a"))).text)

注意：您必须添加以下导入：

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

参考资料

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参考资料