Is there a tool for structuring XML(HTML) based on config (json,xml...)?

Question

HTML

There is a document:

<node>
  <title attr='header'>1</title>
  <child>2</child>
</node>

Are there tools to, for example, pass:

{
  title: '//title[@attr="header"]',
  text: '//child',
  moreText: '//child'
}

And get the desired json object, array, hash at the output?
It would seem that this is not difficult to implement, but there are a lot of cases when nesting appears. When in one place you need to get a text representation, and in another - xml / html. When the structure depends on the conditions ... Perhaps someone has already taken up this.
The task is easy to solve with house-parsers, but I would like to abstract from them. At the same time without inventing your own DSL.

Answer 1

This is what the XSLT language is designed for.
It is itself based on XML and is a language for describing the transformations of a given XML document. The XSLT parser receives the XSLT itself and the original XML document as input. This XSLT can transform the original document as you like (there are constructions for loops, conditions, arithmetic) and generate a new document based on it.