Parsing and altering xml file with custom tool or script

Question

I bump into something like this quite often. This time I have sprite sheet file containing lots of lines like this:

<textureregion id="2" src="blue_ship1.png" x="778" y="791" width="64" height="65" rotated="false" trimmed="false" srcx="0" srcy="0" srcwidth="64" srcheight="65"/>

Now I would need to increment the id on each textureregion by for example 100 and then write the same xml to another file or overwrite the existing. I will have to do this again and again so I need to automate it. I can think of countless of ways to go about this. But I also want to learn something new so, here goes:

How would you complete such a task? Write a custom tool? Script? What language, library or tool would you use? What's the least amount of lines or work you could have this sorted in?

Answer 1

You can use xmlstarlet to edit a xml file.
For example: id ==> id+100

$ xmlstarlet edit --update '/textureregion/@id' -x '.+100'  input.xml
<?xml version="1.0"?>
<textureregion id="102" src="blue_ship1.png" x="778" y="791" width="64" height="65" rotated="false" trimmed="false" srcx="0" srcy="0" srcwidth="64" srcheight="65"/>

You can add --inplace option to edit file inplace.

Answer 2

I'd use an XSL transformation; there are several command-line processors around which can process the data and your stylesheet for you.

XSLT is a powerful language, you can do pretty much any conversion of XML (V1 stylesheets) to XML, HTML or plain text. So while it may not be the "least amount of lines" for simple tasks such as increasing one ID, you can really do pretty much any transformation required.