XSLT - Get data from HTTP Json endpoint and transform it - xslt

Question

I am trying to retrieve JSON data from the HTTP endpoint and use that values in XSLT.
Need help to retrieve data from HTTP URL of JSON data and transform it.
//sample json
{
"userId": 1,
"id": 1,
"title": "delectus aut autem",
"completed": false
}
// xslt
<?xml version="1.0"?>
<xsl:stylesheet
xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="3.0">
<xsl:output method="xml" encoding="UTF-8" indent="yes"/>
<xsl:template match="*">
<person>
<xsl:variable name="title" select="json-to-xml(document('https://jsonplaceholder.typicode.com/todos/1'))/title"/>
<xsl:element name="Field">
<xsl:attribute name="name">Title</xsl:attribute>
<xsl:attribute name="value">
<xsl:value-of select="$title"/>
</xsl:attribute>
</xsl:element>
</person>
</xsl:template>
</xsl:stylesheet> ```
Getting error like Error: org.xml.sax.SAXParseException; systemId: https://jsonplaceholder.typicode.com/todos/1; lineNumber: 1; columnNumber: 1; Content is not allowed in prolog.

Answer 1

To load JSON, you can use json-doc e.g. json-doc('https://jsonplaceholder.typicode.com/todos/1'). That gives you an XDM map for your sample, you can process it with XPath 3.1 e.g.
<xsl:variable name="json" select="json-doc('https://jsonplaceholder.typicode.com/todos/1')"/>
<person>
<Field name="Title" value="{$json?title}"/>
</person>