如何从网络上爬取此类数据并在Python中将其转换为DataFrame？我必须使用 Selenium 才能做到这一点吗？或者BeautifulSoup足以抓取它吗？

Question

我的目标是对于网站https://data.eastmoney.com/executive/000001.html，当你向下滚动时，你会发现一个大桌子 我想把它变成Python中的DataFrame。 BeautifulSoup 足以做到这一点吗？或者我必须使用Selenium？

Stack Overflow 上有人说 BeautifulSoup 无法从网上爬取表数据，所以我尝试了 Selenium，代码如下：

driver = webdriver.Chrome()
driver.get('https://data.eastmoney.com/executive/000001.html')
table_element = driver.find_element_by_xpath("//table")
item_element = table_element.find_element_by_xpath("//tr[2]/td[3]")
item_text = item_element.text
df = pd.DataFrame([item_text], columns=["Item"])
print(df)
driver.quit()

这是结果：

Traceback (most recent call last):
  File "selenium/webdriver/common/service.py", line 76, in start
    stdin=PIPE)
  File "subprocess.py", line 709, in __init__
    restore_signals, start_new_session)
  File "subprocess.py", line 1344, in _execute_child
    raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: 'chromedriver': 'chromedriver'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/tmp/jqcore/jqboson/jqboson/core/entry.py", line 379, in _run
    engine.start()
  File "/tmp/jqcore/jqboson/jqboson/core/engine.py", line 231, in start
    self._dispatcher.start()
  File "/tmp/jqcore/jqboson/jqboson/core/dispatcher.py", line 280, in start
    self._run_loop()
  File "/tmp/jqcore/jqboson/jqboson/core/dispatcher.py", line 240, in _run_loop
    self._loop.run()
  File "/tmp/jqcore/jqboson/jqboson/core/loop/loop.py", line 107, in run
    self._handle_queue()
  File "/tmp/jqcore/jqboson/jqboson/core/loop/loop.py", line 153, in _handle_queue
    message.callback(**message.callback_data)
  File "/tmp/jqcore/jqboson/jqboson/core/mds/market_data_subscriber.py", line 228, in broadcast
    consumer.send(market_data)
  File "/tmp/jqcore/jqboson/jqboson/core/mds/market_data_consumer_manager.py", line 59, in    consumer_gen
    msg_callback()
  File "/tmp/jqcore/jqboson/jqboson/core/mds/market_data_consumer_manager.py", line 52, in   msg_callback
    callback(market_data)
  File "/tmp/jqcore/jqboson/jqboson/core/mds/market_data_consumer_manager.py", line 122, in  wrapper
    result = callback(*args, **kwargs)
  File "/tmp/jqcore/jqboson/jqboson/core/strategy.py", line 474, in _wrapper
    self._context.current_dt
  File "/tmp/strategy/user_code.py", line 85, in handle_data
    driver = webdriver.Chrome()
  File "selenium/webdriver/chrome/webdriver.py", line 73, in __init__
    self.service.start()
  File "selenium/webdriver/common/service.py", line 83, in start
    os.path.basename(self.path), self.start_error_message)
selenium.common.exceptions.WebDriverException: Message: 'chromedriver' executable needs to be in     PATH. Please see https://sites.google.com/a/chromium.org/chromedriver/home

基本上它说“Chromedriver.exe 需要位于 PATH 中”。问题是我正在使用一个名为 JoinQuant (www.joinquant.com) 的在线回测平台，并且所有 Python 文件（例如文件“selenium/webdriver/common/service.py”）都不是本地的 - 它们不在我的计算机上磁盘驱动器。所以这对 Selenium 来说很复杂——我是否必须使用 Selenium 从互联网上抓取这样的数据并将其转换为 Python 中的 DataFrame ？或者我可以使用其他东西，比如 BeautifulSoup 吗？对于 BeautifulSoup 来说，至少它不存在“驱动器需要位于 PATH 中”的问题。

对于 BeautifulSoup，这是我尝试过的：

# Web Crawler
# Sent HTTP Request to get Internet content
url = 'https://data.eastmoney.com/executive/000001.html'
response = requests.get(url)
html_content = response.text

# Check if the request is successful
if response.status_code == 200:
    # Use BeautifulSoup to Analyze Internet information and get the table
    soup = BeautifulSoup(html_content, 'html.parser')
    table = soup.find_all('table')
    # Acquire the rows and columns of the table
    rows = table.find_all('tr')
    data = []
    for row in rows:
        cols = row.find_all('td')
        row_data = []
        for col in cols:
            row_data.append(col.text.strip())
        data.append(row_data)
else:
    print("Failed to Retrieve the Webpage.")

# Set up DataFrame
dataframe = pd.DataFrame(data)
# Print DataFrame
print(dataframe)

这是输出：

Traceback (most recent call last):
  File "/tmp/jqcore/jqboson/jqboson/core/entry.py", line 379, in _run
    engine.start()
  File "/tmp/jqcore/jqboson/jqboson/core/engine.py", line 231, in start
    self._dispatcher.start()
  File "/tmp/jqcore/jqboson/jqboson/core/dispatcher.py", line 280, in start
    self._run_loop()
  File "/tmp/jqcore/jqboson/jqboson/core/dispatcher.py", line 240, in _run_loop
    self._loop.run()
  File "/tmp/jqcore/jqboson/jqboson/core/loop/loop.py", line 107, in run
    self._handle_queue()
  File "/tmp/jqcore/jqboson/jqboson/core/loop/loop.py", line 153, in _handle_queue
    message.callback(**message.callback_data)
  File "/tmp/jqcore/jqboson/jqboson/core/mds/market_data_subscriber.py", line 228, in broadcast
    consumer.send(market_data)
  File "/tmp/jqcore/jqboson/jqboson/core/mds/market_data_consumer_manager.py", line 59, in   consumer_gen
    msg_callback()
  File "/tmp/jqcore/jqboson/jqboson/core/mds/market_data_consumer_manager.py", line 52, in  msg_callback
    callback(market_data)
  File "/tmp/jqcore/jqboson/jqboson/core/mds/market_data_consumer_manager.py", line 122, in  wrapper
    result = callback(*args, **kwargs)
  File "/tmp/jqcore/jqboson/jqboson/core/strategy.py", line 474, in _wrapper
    self._context.current_dt
  File "/tmp/strategy/user_code.py", line 114, in handle_data
    rows = table.find_all('tr')
  File "bs4/element.py", line 1884, in __getattr__
    "ResultSet object has no attribute '%s'. You're probably treating a list of items like a   single item. Did you call find_all() when you meant to call find()?" % key
AttributeError: ResultSet object has no attribute 'find_all'. You're probably treating a list of   items like a single item. Did you call find_all() when you meant to call find()?

但是如果你改变

table = soup.find_all('table')

进入

table = soup.find('table')

结果如下：

Traceback (most recent call last):
  File "/tmp/jqcore/jqboson/jqboson/core/entry.py", line 379, in _run
    engine.start()
  File "/tmp/jqcore/jqboson/jqboson/core/engine.py", line 231, in start
    self._dispatcher.start()
  File "/tmp/jqcore/jqboson/jqboson/core/dispatcher.py", line 280, in start
    self._run_loop()
  File "/tmp/jqcore/jqboson/jqboson/core/dispatcher.py", line 240, in _run_loop
    self._loop.run()
  File "/tmp/jqcore/jqboson/jqboson/core/loop/loop.py", line 107, in run
    self._handle_queue()
  File "/tmp/jqcore/jqboson/jqboson/core/loop/loop.py", line 153, in _handle_queue
    message.callback(**message.callback_data)
  File "/tmp/jqcore/jqboson/jqboson/core/mds/market_data_subscriber.py", line 228, in broadcast
    consumer.send(market_data)
  File "/tmp/jqcore/jqboson/jqboson/core/mds/market_data_consumer_manager.py", line 59, in   consumer_gen
    msg_callback()
  File "/tmp/jqcore/jqboson/jqboson/core/mds/market_data_consumer_manager.py", line 52, in msg_callback
    callback(market_data)
  File "/tmp/jqcore/jqboson/jqboson/core/mds/market_data_consumer_manager.py", line 122, in wrapper
    result = callback(*args, **kwargs)
  File "/tmp/jqcore/jqboson/jqboson/core/strategy.py", line 474, in _wrapper
    self._context.current_dt
  File "/tmp/strategy/user_code.py", line 114, in handle_data
    rows = table.find_all('tr')
AttributeError: 'NoneType' object has no attribute 'find_all'

总而言之，我应该使用哪一个？硒还是 BeautifulSoup？或者甚至是其他什么？我应该如何解决这个问题？

Answer 1

我看到的主要问题是您使用的是非常旧的 Selenium 版本，并且您没有指定 Chromedriver 的路径（并且它不在 PATH 中），因此它找不到它。如果您更新到最新的 Selenium（至少 4.6），他们添加了一个内置的浏览器管理器 SeleniumManager，它将负责下载和配置您需要的任何驱动程序。

如果你确实走这条路，一旦升级 Selenium，你就会看到

.find_element_by_*()

，例如

.find_element_by_xpath()

，不再工作了。您需要将它们更改为新语法，

from selenium.webdriver.common.by import By

driver.find_element(By.XPATH, "//table")

对于您的 Beautiful Soup 错误...我对此没有经验，但通过查看堆栈跟踪和错误消息，我认为问题出在这些线上

table = soup.find_all('table')
rows = table.find_all('tr')

table

是一个集合，您对该集合执行了

.find_all()

，但这不起作用。如果您将

.find_all('table')

更改为

.find('table')

，它应该可以工作。更新了下面的代码，

table = soup.find('table')
rows = table.find_all('tr')