[SOLVED] [XMLStarlet] Edit+insert elements?

littlebigman · 09-03-2021, 09:44 AM

Hello,

In case someone here already knows how to use the XMLStarlet application to edit KML files, I need to…

1. Check if kml/Document/name exists: If it does, edit its name; If it doesn't, insert a new element
2. Add a sibling to all LineString elements.

It looks like XMLStarlet supports it, but I don't know enough about XPath yet to figure it out.

Thank you.

Code:

xml el input.kml

kml
kml/Document
kml/Document/Placemark
kml/Document/Placemark/name
kml/Document/Placemark/ExtendedData
kml/Document/Placemark/ExtendedData/Data
kml/Document/Placemark/ExtendedData/Data/value
kml/Document/Placemark/LineString
kml/Document/Placemark/LineString/coordinates

ondoho · 09-03-2021, 12:05 PM

I'm not sure what you're asking, it's very broad.
Assuming kml is some sort of subset of XML, then yes, xmlstarlet can.
Here's a good overview (no https!) I have perused.

Quote:

Originally Posted by littlebigman

Hello,

In case someone here already knows how to use the XMLStarlet application to edit KML files, I need to…

1. Check if kml/Document/name exists: If it does, edit its name; If it doesn't, insert a new element
2. Add a sibling to all LineString elements.

It looks like XMLStarlet supports it, but I don't know enough about XPath yet to figure it out.

Thank you.

Code:

xml el input.kml

kml
kml/Document
kml/Document/Placemark
kml/Document/Placemark/name
kml/Document/Placemark/ExtendedData
kml/Document/Placemark/ExtendedData/Data
kml/Document/Placemark/ExtendedData/Data/value
kml/Document/Placemark/LineString
kml/Document/Placemark/LineString/coordinates

shruggy · 09-04-2021, 07:11 AM

The first task seems obvious from the output you provided.

Code:

#!/bin/sh
file='input.kml'
cmd=xml
name='Route Map'
# xmlstarlet is picky about namespaces
grep -q 'xmlns=' "$file" && ns=_: || ns=

if $cmd el "$file" | grep -qx 'kml/Document/name'
then $cmd ed -u //${ns}Document/${ns}name -v "$name" "$file"
else $cmd ed -s //${ns}Document -t elem -n name -v "$name" "$file"
fi

But I don't get what you're trying to do in the second task as it is too vaguely formulated. I mean xml ed -i //LineString and xml ed -a //LineString would insert an element just above or just below every LineString, respectively. Is that what you want?

littlebigman · 09-17-2021, 10:43 AM

Thank you.