How to remove all occurences of element in XML file? - python

I'd like to edit a KML file and remove all occurences of ExtendedData elements, wherever they are located in the file.
Here's the input XML file:
<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://earth.google.com/kml/2.2">
<Document>
<Style id="placemark-red">
<IconStyle>
<Icon>
<href>http://maps.me/placemarks/placemark-red.png</href>
</Icon>
</IconStyle>
</Style>
<name>My track</name>
<ExtendedData xmlns:mwm="https://maps.me">
<mwm:name>
<mwm:lang code="default">Blah</mwm:lang>
</mwm:name>
<mwm:lastModified>2020-04-05T14:17:18Z</mwm:lastModified>
</ExtendedData>
<Placemark>
<name></name>
…
<ExtendedData xmlns:mwm="https://maps.me">
<mwm:localId>0</mwm:localId>
<mwm:visibility>1</mwm:visibility>
</ExtendedData>
</Placemark>
</Document>
</kml>
And here's the code that 1) only removes the outermost occurence, and 2) requires adding the namespace to find it:
from lxml import etree
from pykml import parser
from pykml.factory import KML_ElementMaker as KML
with open("input.xml") as f:
doc = parser.parse(f)
root = doc.getroot()
ns = "{http://earth.google.com/kml/2.2}"
for pm in root.Document.getchildren():
#No way to get rid of namespace, for easier search?
if pm.tag==f"{ns}ExtendedData":
root.Document.remove(pm)
#How to remove innermost occurence of ExtendedData?
print(etree.tostring(doc, pretty_print=True))
Is there a way to remove all occurences in one go, or should I parse the whole tree?
Thank you.
Edit: The BeautifulSoup solution below requires adding an option "BeautifulSoup(my_xml,features="lxml")" to avoid the warning "No parser was explicitly specified".

Here's a solution using BeautifulSoup:
soup = BeautifulSoup(my_xml) # this is your xml
while True:
elem = soup.find("extendeddata")
if not elem:
break
elem.decompose()
Here's the output for your data:
<?xml version="1.0" encoding="UTF-8"?>
<html>
<body>
<kml xmlns="http://earth.google.com/kml/2.2">
<document>
<style id="placemark-red">
<IconStyle>
<Icon>
<href>http://maps.me/placemarks/placemark-red.png</href>
</Icon>
</IconStyle>
</style>
<name>
My track
</name>
<placemark>
<name>
</name>
</placemark>
</document>
</kml>
</body>
</html>

If you know the XML structure, try:
xml_root = ElementTree.parse(filename_path).getroot()
elem = xml_root.find('./ExtendedData')
xml_root.remove(elem)
or
xml_root = ElementTree.parse(filename_path).getroot()
p_elem = xml_root.find('/Placemark')
c_elem = xml_root.find('/Placemark/ExtendedData')
p_elem.remove(c_elem)
play with this ideas :)
if you don't know the xml structure, I think you need to parse the whole tree.

Simply run the empty template with Identity Transform using XSLT 1.0 which Python's lxml can run. No for/while loops or if logic needed. To handle the default namespace, define a prefix like doc:
XSLT (save a .xsl file, a special .xml file)
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:doc="http://earth.google.com/kml/2.2">
<xsl:output method="xml" omit-xml-declaration="yes" indent="yes"/>
<xsl:strip-space elements="*"/>
<!-- IDENTITY TRANSFORM -->
<xsl:template match="node()|#*">
<xsl:copy>
<xsl:apply-templates select="node()|#*"/>
</xsl:copy>
</xsl:template>
<!-- REMOVE ALL OCCURRENCES OF NODE -->
<xsl:template match="doc:ExtendedData"/>
</xsl:stylesheet>
Python
import lxml.etree as et
# LOAD XML AND XSL SOURCES
xml = et.parse('Input.xml')
xsl = et.parse('XSLT_Script.xsl')
# TRANSFORM INPUT
transform = et.XSLT(xsl)
result = transform(xml)
# PRINT TO SCREEN
print(result)
# SAVE TO FILE
with open('Output.kml', 'wb') as f:
f.write(result)

Related

Python XML/Pandas: How to merge nested XML?

How can I join two different pieces of information together from this XML file?
# data
xml1 = ('''<?xml version="1.0" encoding="utf-8"?>
<TopologyDefinition xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<RSkus>
<RSku ID="V1" Deprecated="true" Owner="Unknown" Generation="1">
<Devices>
<Device ID="1" SkuID="Switch" Role="xD" />
</Devices>
<Blades>
<Blade ID="{1-20}" SkuID="SBlade" />
</Blades>
<Interfaces>
<Interface ID="COM" HardwareID="NS1" SlotID="COM1" Type="serial" />
<Interface ID="LINK" HardwareID="TS1" SlotID="UPLINK_1" Type="serial" />
</Interfaces>
<Wires>
<WireGroup Type="network">
<Wire LocationA="NS1" SlotA="{1-20}" LocationB="{1-20}" SlotB="NIC1" />
</WireGroup>
<WireGroup Type="serial">
<Wire LocationA="TS1" SlotA="{7001-7020}" LocationB="{1-20}" SlotB="COM1" />
</WireGroup>
</Wires>
</RSku>
</RSkus>
</TopologyDefinition>
''')
While this is a single case and trivial in the instance below; if I run the below commands on the full file, I get shapes that do not match and therefore cannot be joined so easily.
How can I extract the XML information such that for every row, I get all the RSku information PLUS its Blade information. Each xpath contains no information that would let me join it to another xpath so that I may combine the information.
# how to have them joined?
pd.read_xml(xml1, xpath = ".//RSku")
pd.read_xml(xml1, xpath = ".//Blade")
# expected
pd.concat([pd.read_xml(xml1, xpath = ".//RSku"), pd.read_xml(xml1, xpath = ".//Blade")], axis=1)
Consider transforming the XML with XSLT by flattening the document with information you need. Specifically, retrieve only Blade attributes using descendant::* axis and corresponding RSku attributes using the ancestor::* axis. Python' lxml (default parser of pandas.read_xml) can run XSLT 1.0 scripts.
Below XSLT's <xsl:for-each> is used to prefix RSku_ and Blade_ to attribute names since they share same attribute such as ID. Otherwise template would be much less wordy.
import pandas as pd
xml1 = ...
xsl = ('''<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
version="1.0">
<xsl:output method="xml" indent="yes"/>
<xsl:template match="/TopologyDefinition">
<root>
<xsl:apply-templates select="descendant::Blade"/>
</root>
</xsl:template>
<xsl:template match="Blade">
<data>
<xsl:for-each select="ancestor::RSku/#*">
<xsl:attribute name="{concat('RSku_', name())}">
<xsl:value-of select="."/>
</xsl:attribute>
</xsl:for-each>
<xsl:for-each select="#*">
<xsl:attribute name="{concat('Blade_', name())}">
<xsl:value-of select="."/>
</xsl:attribute>
</xsl:for-each>
</data>
</xsl:template>
</xsl:stylesheet>''')
blades_df = pd.read xml(xml1, stylesheet=xsl)
Online XSLT Demo

How do I insert a tag that holds the text of an older tag in xml using python?

I want to insert s tags inside a tag that already exists and move the text of the older tag inside the s tag. For example, if my XML file looks like this:
<root>
<name>Light and dark</name>
<address>
<sector>142</sector>
<location>Noida</location>
</address>
</root>
I want it to be like this (check the name tag):
<root>
<name>
<s>Light and dark</s>
</name>
<address>
<sector>142</sector>
<location>Noida</location>
</address>
</root>
I tried using ET.SubElement but it doesn't give me the same result.
It it much better to use XSLT for such tasks.
XSLT has so called Identity Transform pattern.
Input XML
<root>
<name>Light and dark</name>
<address>
<sector>142</sector>
<location>Noida</location>
</address>
</root>
XSLT
<?xml version="1.0"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" encoding="utf-8" indent="yes" omit-xml-declaration="yes"/>
<xsl:strip-space elements="*"/>
<xsl:template match="#*|node()">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="name">
<xsl:copy>
<s>
<xsl:value-of select="."/>
</s>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
Output XML
<root>
<name>
<s>Light and dark</s>
</name>
<address>
<sector>142</sector>
<location>Noida</location>
</address>
</root>
To insert a sub-element in the XML using ElementTree XML API, append the new element then set it with the text value of the parent element.
import xml.etree.ElementTree as ET
xml = """
<root>
<name>Light and dark</name>
<address>
<sector>142</sector>
<location>Noida</location>
</address>
</root>"""
root = ET.fromstring(xml)
# 1. find name element in document
name = root.find('name')
# 2. get text value and reset the element
text = name.text
name.clear()
# 3. create new element s and set text
elt = ET.SubElement(name, "s")
elt.text = text
print(ET.tostring(root, encoding='unicode'))
To process multiple elements, add a loop around steps 1-3:
for child in root.findall('name'):
text = child.text
child.clear()
elt = ET.SubElement(child, "s")
elt.text = text
Output:
<root>
<name><s>Light and dark</s></name>
<address>
<sector>142</sector>
<location>Noida</location>
</address>
</root>

lxml throwing xslt parse error - not able to template match any other than root

I'm using python/lxml to translate source xml to a target xml format. I keep getting a XLSTParseError when I try to match template to any other elements than root ('/') but cannot figure out what is wrong - pretty sure its namespace related though...The content i am trying to access from source xml is contained in the elements. Any idea how to fix or how to get lxml to output more detailed error msg?
Source xml has declaration:
<?xml version="1.0" encoding="UTF-8"?>
<dataroot generated="2016-10-24T09:16:37" xsi:noNamespaceSchemaLocation="BOLIG_XML.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:od="urn:schemas-microsoft-com:officedata">
<BOLIG_XML>...</BOLIG_XML>
<BOLIG_XML>...</BOLIG_XML>
...
Target xml has declaration:
<?xml version="1.0" encoding="utf-8"?>
<BoligListe xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:oio:lbf:1.0.0">
<BoligStruktur>...</BoligStruktur>
<BoligStruktur>...</BoligStruktur>
...
XSLT currently looks like this:
xslt_tree = etree.XML('''\
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="/">
<BoligListe xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:oio:lbf:1.0.0">
<xsl:template match="BOLIG_XML">
<BoligStruktur>hello world</BoligStruktur>
</xsl:template>
</BoligListe>
</xsl:template>
</xsl:stylesheet>'''
)
Each xsl:template element needs to be a top level element of the stylesheet root element, you can't nest templates as you seem to try to do in your XSLT code. You then use xsl:apply-templates to process child elements with a matching template so I guess you want
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="/">
<BoligListe xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:oio:lbf:1.0.0">
<xsl:apply-templates/>
</BoligListe>
</xsl:template>
<xsl:template match="BOLIG_XML">
<BoligStruktur>hello world</BoligStruktur>
</xsl:template>
</xsl:stylesheet>

Save (print) xml node with its parents but without children

From the XML document, I want to save one node to a file - with all parent nodes, but without any child nodes. For example, for the following XML:
<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://earth.google.com/kml/2.1">
<Document id="myid">
<name>ref.kml</name>
<Style id="normalState">
<IconStyle><scale>1.0</scale><Icon><href>yt.png</href></Icon></IconStyle>
</Style>
</Document>
</kml>
expected output for <Document> node will be like this:
<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://earth.google.com/kml/2.1">
<Document id="myid">
</Document>
</kml>
So far I only found a solution with iterated removal of all child elements before saving. But as I need to work with original XML after, I have to make a copy of the whole document:
#!/usr/bin/env python
import lxml.etree as ET # have to use [lxml] because [xml] doesn't support 'xml_declaration'
import copy
kml_file = ET.parse("myfile.kml")
kml_copied = copy.deepcopy(kml_file) # .copy() is not enough, need .deepcopy()
root = kml_copied.getroot()
my_node = root[0]
for child in my_node:
my_node.remove(child)
print ET.tostring(kml_copied, xml_declaration=True, encoding='utf-8')
Is there better way to do this? at least to avoid making a deepcopy of the whole document...
Consider XSLT, the special-purpose declarative language designed to transform XML documents. And Python's lxml module has a built-in XSLT 1.0 processor. Additionally XSLT (whose script is a well-formed xml document can also adequately handle the kml undeclared namespace):
XSLT Script (save as .xsl to be loaded in Python, also portable to other languages)
<xsl:transform xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"
xmlns:doc="http://earth.google.com/kml/2.1">
<xsl:output version="1.0" encoding="UTF-8" indent="yes" />
<xsl:strip-space elements="*"/>
<!-- Identity Transform to copy entire document -->
<xsl:template match="#*|node()">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
</xsl:copy>
</xsl:template>
<!-- Empty Template to Remove Nodes -->
<xsl:template match="doc:Style|doc:name"/>
</xsl:transform>
Python Script
import lxml.etree as ET
# LOAD XML AND XSL
dom = ET.parse('Input.xml')
xslt = ET.parse('XSLTScript.xsl')
# TRANSFORM INPUT INTO DOM OBJECT
transform = ET.XSLT(xslt)
newdom = transform(dom)
# OUTPUT DOM TO STRING
tree_out = ET.tostring(newdom,
encoding='UTF-8',
pretty_print=True,
xml_declaration=True)
print(tree_out.decode("utf-8"))
# SAVE RESULTING XML
xmlfile = open('Output.xml','wb')
xmlfile.write(tree_out)
xmlfile.close()
Output
<?xml version='1.0' encoding='UTF-8'?>
<kml xmlns="http://earth.google.com/kml/2.1">
<Document id="myid"/>
</kml>

how to add xml child node with namespace in python?

i'm realy stuck in this, i got a file with an xml layout like this:
<rss xmlns:irc="SomeName" version="2.0">
<channel>
<item>
<irc:title>A title</irc:title>
<irc:poster>A poster</irc:poster>
<irc:url>An url</irc:url>
</item>
</channel>
</rss>
i need to add another 'item' in channel node, that's easy, but i can't find the way to add the item's child with the namespace.
i'm trying with lxml, but the documentation is not so clear for a newbie
please any help will be appreciated.
i find the way to doit with lxml
root = xml.getroot()
channel = root.find('channel')
item = et.Element('item')
title = et.SubElement(item,'{SomeName}title')
title.text = 'My new title'
poster = et.SubElement(item,'{SomeName}poster')
poster.text = 'My poster'
poster = et.SubElement(item,'{SomeName}url')
poster.text = 'http://My.url.com'
channel.append(item)
but still interested in a better solution
Alternatively, you can use XSLT, the declarative programming language, that transforms, styles, re-formats, and re-structures XML files in any way, shape, or form. Python's lxml module maintains an XSLT processor.
Simply, register the needed namespace in the XSLT's declaration line and use it in any new node. This might appear to be overkill for your current need but there could be a situation where a more complex transformation is needed with appropriate namespaces. Below adds a new title to the previous poster and URL.
XSLT (to be saved as .xsl)
<?xml version="1.0" ?>
<xsl:transform xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"
xmlns:irc="SomeName">
<xsl:strip-space elements="*" />
<xsl:output method="xml" indent="yes"/>
<xsl:template match="rss">
<rss>
<channel>
<xsl:for-each select="//item">
<item>
<irc:title>My new title</irc:title>
<xsl:copy-of select="irc:poster"/>
<xsl:copy-of select="irc:url"/>
</item>
</xsl:for-each>
</channel>
</rss>
</xsl:template>
</xsl:transform>
Python
import os
import lxml.etree as ET
# SET CURRENT DIRECTORY
cd = os.path.dirname(os.path.abspath(__file__))
# LOAD IN XML AND XSL FILES
dom = ET.parse(os.path.join(cd, 'Original.xml'))
xslt = ET.parse(os.path.join(cd, 'XSLT_Script.xsl'))
# TRANSFORM
transform = ET.XSLT(xslt)
newdom = transform(dom)
# OUTPUT FINAL XML
tree_out = ET.tostring(newdom, encoding='UTF-8', pretty_print=True, xml_declaration=True)
xmlfile = open(os.path.join(cd, 'output.xml'),'wb')
xmlfile.write(tree_out)
xmlfile.close()
Output
<?xml version="1.0" encoding="UTF-8"?>
<rss xmlns:irc="SomeName">
<channel>
<item>
<irc:title>My new title</irc:title>
<irc:poster>A poster</irc:poster>
<irc:url>An url</irc:url>
</item>
</channel>
</rss>

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