xmlstarlet is unable to add subnode when more than one xmlns attribute is present in the first element

Question

I have an xml file test.gpx:

cat test.gpx

<?xml version="1.0" encoding="UTF-8"?>
<gpx xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.topografix.com/GPX/1/1">
  <trk>
    <name>Name 1</name>
    <desc>Description 1</desc>
  </trk>
  <trk>
    <name>Name 2</name>
    <desc>Description 2</desc>
  </trk>
</gpx>

xmlstartlet is not able to perform successfully when trying to insert a subnode in this file:

xmlstarlet edit --subnode "/gpx/trk" --type  elem -n "new" -v "Hello World!" test.gpx

<?xml version="1.0" encoding="UTF-8"?>
<gpx xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.topografix.com/GPX/1/1">
  <trk>
    <name>Name 1</name>
    <desc>Description 1</desc>
  </trk>
  <trk>
    <name>Name 2</name>
    <desc>Description 2</desc>
  </trk>
</gpx>

Whereas with only one attribute in the first gpx element, it works:

xmlstarlet edit --subnode "/gpx/trk" --type  elem -n "new" -v "Hello World!" test.gpx

<?xml version="1.0" encoding="UTF-8"?>
<gpx xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <trk>
    <name>Name 1</name>
    <desc>Description 1</desc>
    <new>Hello World!</new>
  </trk>
  <trk>
    <name>Name 2</name>
    <desc>Description 2</desc>
    <new>Hello World!</new>
  </trk>
</gpx>

Hence my question: how could I succeed with the original file, having more than one attribute in its first gpx element?

Version info:

xmlstarlet --version
1.6.1
compiled against libxml2 2.9.10, linked with 20913
compiled against libxslt 1.1.34, linked with 10134

On Ubuntu 22.04.

Jack Fleeting · Accepted Answer · 2023-11-20 02:46:26Z

2

The attributes your are dealing with aren't just garden variety attributes - they are namespaces and have to be taken into account accordingly. Since you have a default namespace in your first (but not second) file, you can deal with it in one of two ways.

The long, explicit way:

xmlstarlet ed -N x=http://www.topografix.com/GPX/1/1 --subnode "/x:gpx/x:trk" --type  elem -n "new" -v "Hello World!" test.gpx

or the shorter:

xmlstarlet ed  --subnode "/_:gpx/_:trk" --type  elem -n "new" -v "Hello World!" test.gpx

Either one should give you your expected output.

answered Nov 20, 2023 at 2:46

Jack Fleeting

25k6 gold badges27 silver badges49 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

swiss_knight Over a year ago

It seems to work, thanks, but how could I add an associated namespace into the first gpx tag. It should be "xmlns:ogr="http://osgeo.org/gdal". Currently, nothing is added.

Jack Fleeting Over a year ago

@swiss_knight - A few things: first, your question didn't mention anything about adding a new namespace declaration; as its title says, it asks about adding a subnode which is what the answer does. Second, not sure how the namespace you suggest is "associated" with the new node.

Collectives™ on Stack Overflow

xmlstarlet is unable to add subnode when more than one xmlns attribute is present in the first element

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related