Sample code using eXist-db json-ignore-whitespace-text-nodes parameter

json-ignore-whitespace-text-nodes-param.xq

xquery version "3.1";

(: @see https://github.com/eXist-db/exist/commit/53bdb54c664a8063e43392e0b0fb9eac57baf67d#diff-fc5225a3545e6b6807e7810bc9e40219500842a68dbb49a7eb83670016b160ab :)

declare boundary-space preserve;

let $json-ignore-whitespace-text-nodes-param-xml := 
    <output:serialization-parameters xmlns:output="http://www.w3.org/2010/xslt-xquery-serialization">
        <output:method value="json"/>
        <exist:json-ignore-whitespace-text-nodes value="yes"/>
    </output:serialization-parameters>

let $json-ignore-whitespace-text-nodes-param-map := 
    map {
        "method": "json",
        "exist:json-ignore-whitespace-text-nodes": true()
    }

let $source := 
    <a z='99'>
        <b x='1'/>
        <b x='2'></b>
        <b x='3'>stuff</b>
        <b x='4'>     </b>
    </a>

return
    (
        fn:serialize($source, $json-ignore-whitespace-text-nodes-param-xml),
        fn:serialize($source, $json-ignore-whitespace-text-nodes-param-map)
    )

json-ignore-whitespace-text-nodes-param_results.txt

{"z":"99","b":[{"x":"1"},{"x":"2"},{"x":"3","#text":"stuff"},{"x":"4"}]}
{"z":"99","b":[{"x":"1"},{"x":"2"},{"x":"3","#text":"stuff"},{"x":"4"}]}