Python - lxml delete some xml tags and move others

Question

I am trying to open an xml, delete whole tags and their contents, and move other tags around within the xml.

Here is my original import xml:

<?xml version="1.0" encoding="UTF-8"?>
<package>
    <language>en-GB</language>
    <video>
        <original_spoken_locale>en-US</original_spoken_locale>
        <copyright_cline>2012 copyright</copyright_cline>
        <release_date>2012-04-23</release_date>
        <title>Amazing Film</title>
    </video>
    <provider>testprovider</provider>
</package>

I need to remove the <copyright_cline> tag and the <title> tag. Then I need to move the <provider> tag up into the <video> tag and position it between below the <original_spoken_locale> tag and also move the <release_date> tag down below the <video> tag.

Here is the resulted export xml:

<?xml version="1.0" encoding="UTF-8"?>
<package>
    <language>en-GB</language>
    <video>
        <original_spoken_locale>en-US</original_spoken_locale>
        <provider>testprovider</provider>
        <release_date>2012-04-23</release_date>
    </video>
    <release_date>2012-04-23</release_date>
</package>

I have now sucsessfully installed lxml, so looking for a solution for that ideally.

Kind regards.

I have been able to remove the unwanted tags and their contents, but still need to be able to re-order / move the other tags around, preferably without replacing. I'm also having trouble removing this line of xml code"

<!--Carpet ID: fd54678-->

Here is what I currently have:

from lxml import etree

xmlFileIn = '/xmls/metadata.xml'
xmlFileOut = '/xmls/output.xml'

tree = etree.parse(xmlFileIn)
root = tree.getroot()

etree.strip_elements(root, 'assets')
etree.strip_tags(root, 'assets')

etree.strip_elements(root, 'chapters')
etree.strip_tags(root, 'chapters')

etree.strip_elements(root, 'xid')
etree.strip_tags(root, 'xid')

# Write the new xml file
tree.write(xmlFileOut, pretty_print=True, xml_declaration=True, encoding="utf-8")

So I still need to remove the  tag. I want to remove these via wildcards as there are many , as the content in the middle will change. and I also need to know how to move blocks of tags around.

Community · Accepted Answer · 2017-05-23 11:45:53Z

Since no one else has answered yet, I'll try; but I'm going from reading rather than experimentation. Apologies in advance if I've missed anything….

For how to move elements, see Move an entire element in with lxml.etree

As noted there, be especially careful because text nodes are not nodes in lxml (see below).

As for comments, I couldn't find any way in lxml to get at comments, or to directly "move" elements. You might strip them with 'sed' or something first.

Cautions

Elementtree and hence lxml seem keen on having only one kind of node. This has a few consequences that can be problematic ("Things should be as simple as possible, but no simpler"):

Working with comments (as in this case) or PIs is harder, because they aren't first-class notions in the model.
Text is especially difficult, because lxml and elementtree make text following the end-tag of any XML element, into a property of that element (the "tail text"). It's treated as on par with that element's type-name, attributes, and children. This can sort of work (it's a Turing Machine, y'know), but it requires quite a different way of thinking.

I noticed that writers about lxml often state that it's mainly for XML structures that really don't have much text. The example you gave seems like that; if so you're fortunate. But when text matters, even something as simple as this:

 <p>As everyone<footnote>Well, almost everyone</footnote> knows...</p>

the text " knows..." is part of the <footnote> node in lxml. When you move or delete or replace the footnote, the text goes with it. But of course that text isn't part of the footnote (it occurred after the footnote ended, after all).

I have no idea what lxml does with the "As everyone" -- it doesn't come right after the end of any element. I couldn't find anything on how lxml handles that.

So be very careful if there's any text content anywhere.

Collectives™ on Stack Overflow

Python - lxml delete some xml tags and move others

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related