Question

我正在使用requests来获取网页，例如如下。

import requests
from bs4 import BeautifulSoup
url = "http://www.ofsted.gov.uk/inspection-reports/find-inspection-report/provider/CARE/EY298883"
r = requests.get(url)
soup = BeautifulSoup(r.text)

对于这些页面中的每一页，我想获得第一个在“最新报告”部分中指出的pdf。你怎么能用美味的汤做到这一点？

HTML的相关部分是

 <tbody>
 <tr>
          <th scope="col">Latest reports</th>
          <th scope="col" class="date">Inspection <br/>date</th>
          <th scope="col" class="date">First<br/>publication<br/>date</th>
          </tr>
          <tr>
            <td><a href="/provider/files/1266031/urn/106428.pdf"><span class="icon pdf">pdf</span> Early years inspection report </a></td>
            <td class="date">12 Mar 2009</td>
            <td class="date">4 Apr 2009</td>
            </tr>        </tbody>

以下代码看起来应该可以工作但不会。

ofstedbase = "http://www.ofsted.gov.uk"
for col_header in soup.findAll('th'):
    if not col_header.contents[0] == "Latest reports": continue
    for link in col_header.parent.parent.findAll('a'):
        if 'href' in link.attrs and link['href'].endswith('pdf'): break
    else:
        print '"Latest reports" PDF not found'
        break
    print '"Latest reports" PDF points at', link['href']
    p = requests.get(ofstedbase+link['href'])
    print p.content
    break

问题是p包含另一个网页，而不是它应该的pdf。有没有办法获得实际的PDF格式？

更新

让它再使用BeautifulSoup的一次迭代

 souppage = BeautifulSoup(p.text)
 line = souppage.findAll('a',text=re.compile("requested"))[0]
 pdf = requests.get(ofstedbase+line['href'])

感激地收到任何更好/更好的解决方案。

Answer 1

这不是最干净的解决方案，但您可以遍历列标题，直到找到“最新报告”，然后在该表中搜索指向PDF文件的第一个链接。

for col_header in soup.findAll('th'):
    if not col_header.contents[0] == "Latest reports": continue
    for link in col_header.parent.parent.findAll('a'):
        if 'href' in link.attrs and link['href'].endswith('pdf'): break
    else:
        print '"Latest reports" PDF not found'
        break
    print '"Latest reports" PDF points at', link['href']
    break

您可以尝试使用Selenium WebDriver（python -m "easy_install" selenium）自动指示Firefox下载该文件。这需要Firefox：

from selenium import webdriver
from bs4 import BeautifulSoup

profile = webdriver.FirefoxProfile()
profile.set_preference('browser.helperApps.neverAsk.saveToDisk', ('application/pdf'))
profile.set_preference("pdfjs.previousHandler.alwaysAskBeforeHandling", False)
profile.set_preference("browser.helperApps.alwaysAsk.force", False)
profile.set_preference("browser.download.manager.showWhenStarting", False)

driver = webdriver.Firefox(firefox_profile = profile)
base_url = "http://www.ofsted.gov.uk"
driver.get(base_url + "/inspection-reports/find-inspection-report/provider/CARE/EY298883")
soup = BeautifulSoup(driver.page_source)

for col_header in soup.findAll('th'):
    if not col_header.contents[0] == "Latest reports": continue
    for link in col_header.parent.parent.findAll('a'):
        if 'href' in link.attrs and link['href'].endswith('pdf'): break
    else:
        print '"Latest reports" PDF not found'
        break
    print '"Latest reports" PDF points at', link['href']
    driver.get(base_url + link['href'])

这个解决方案非常强大，因为它可以完成人类用户所能做的一切，但它有缺点。例如，我试图解决Firefox提示下载的问题，但它对我不起作用。结果可能会因您安装的附加组件和Firefox版本而异。

Answer 2

让它再使用BeautifulSoup的一次迭代

 souppage = BeautifulSoup(p.text)
 line = souppage.findAll('a',text=re.compile("requested"))[0]
 pdf = requests.get(ofstedbase+line['href'])

如何从网页链接JS重定向的pdf

2 个答案: