Why is my XPath to select text not working?

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How do you access a text in an XPath if it doesn't have a node? The text is in quotation marks and on seperate line inside another node

I'm having trouble choosing the correct element in an XPath

 <span>
    <a href="www.imagine_a_link_here.org">
      "
                This is the text I need to access
             "
    </a>
 </span>

I'd normally do this by writing

import requests
from lxml import html,etree
from lxml.html import document_fromstring

page = requests.get('https://www.the_link_im_trying_to_webscrape.org')
tree = html.fromstring(page.content)
the_text_i_need_to_access_xpath = '/span/a/text()'
the_text_i_need_to_access = tree.xpath(the_text_i_need_to_access_xpath)

Unfortunately this is only returning an empty list. Does anyone know how I have to modify the XPath in order to get the string I'm looking for?

lxml web-scraping xpath xml python
1 Answers

How do you access a text in an XPath if it doesn't have a node?

Text in an XML or HTML document will be associated with a node. That's not the problem here. And the " " delimiters are just there to show you surrounding whitespace.

As presented your XPath should select the text within the a element. Here're some reasons that may not be happening:

  1. As @MadsHansen mentioned in comments, the root element of your actual HTML may not be a span as shown. See:

  2. The text may not be loaded at the time of your XPath execution because the document hasn't completely loaded or because JavaScript dynamically changes the DOM later. See:

  3. fromstring() can use a bit more magic than might be expected:

fromstring(string): Returns document_fromstring or fragment_fromstring, based on whether the string looks like a full document, or just a fragment.

Given this, here is an update to your code that will select the targeted text as expected:

import requests
from lxml import html
from lxml.html import document_fromstring

htmlstr = """
<span>
   <a href="www.imagine_a_link_here.org">
     "
               This is the text I need to access
            "
   </a>
</span>
"""

tree = html.fromstring(htmlstr)
print(html.tostring(tree))
the_text_i_need_to_access_xpath = '//span/a/text()'
the_text_i_need_to_access = tree.xpath(the_text_i_need_to_access_xpath)
print(the_text_i_need_to_access)

Or, if you don't need/want the HTML surprises, this also selects the text:

import lxml.etree as ET

xmlstr = """
 <span>
    <a href="www.imagine_a_link_here.org">
      "
                This is the text I need to access
             "
    </a>
 </span>
"""

root = ET.fromstring(xmlstr)
print(root.xpath('/span/a/text()'))

Credit: Thanks to @ThomasWeller for pointing out the additional complications and helping to resolve them.

user_2900850
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