Python ElementTree - Cannot find Element with attribute xml:lang

Question

Using ElementTree Python library, I need to find the element display-name and parent:

This is the Python code that is including also the sample XML:

import xml.etree.ElementTree as ET

ns = {'d': 'http://www.demandware.com/xml/impex/catalog/2006-10-31'}

root = ET.fromstring("""<?xml version="1.0" encoding="UTF-8"?>
<catalog xmlns="http://www.demandware.com/xml/impex/catalog/2006-10-31" catalog-id="my-catalog-id">
    <category category-id="my_id1">
        <display-name xml:lang="cs-CZ">Bla bla 1</display-name>
        <online-flag>false</online-flag>
    </category>
    <category category-id="my_id2">
        <display-name xml:lang="cs-CZ">Bla bla 2</display-name>
        <online-flag>false</online-flag>
        <parent>my_id1</parent>
    </category>
</catalog>
""")

def parse_category(category_node):
    category_id = category_node.attrib['category-id']
    is_online = category_node.find('d:online-flag', ns).text == "true"
    display_name_node = category_node.find('d:display-name', ns) # FIXME
    display_name = display_name_node.text if display_name_node else ''
    parent_node = category_node.find('d:parent', ns)
    parent_id = parent_node.text if parent_node else ''

    print("{} | {} | {} | {}".format(category_id, display_name, is_online, parent_id))

for child in root:
    print(child)
    if child.tag == "{{{0}}}category".format(ns['d']):
        parse_category(child)

Altough the display_name_node and parent_node variable are available for the node with id "my_id2", the text is not extracted in display_name and parent_id variables

Please post a [mcve]. What you've posted doesn't demonstrate the problem -- `parse_category()` isn't even called. — kjhughes, Aug 05 '22 at 11:26
I think it's the problem discussed here: https://stackoverflow.com/q/20129996/407651 — mzjn, Aug 05 '22 at 12:39

score 0 · Answer 1 · answered Aug 05 '22 at 11:59

I noticed that changin from:

display_name = display_name_node.text if display_name_node else ''
parent_id = parent_node.text if parent_node else ''

to

display_name = display_name_node.text if display_name_node is not None else ''
parent_id = parent_node.text if parent_node is not None else ''

solves the problem, but I'm not quite sure why.

Python ElementTree - Cannot find Element with attribute xml:lang

1 Answers1