JSON to XML Conversion: Complete Guide

JSON vs XML Structure

JSON and XML both represent structured data but with different philosophies. JSON uses key-value pairs and arrays. XML uses elements, attributes, and text nodes. Converting between them requires mapping these concepts.

JSON to XML in JavaScript

// Using xml-js library
const xmljs = require('xml-js');

const json = { person: { name: 'Alice', age: 30, hobbies: { hobby: ['reading', 'coding'] } } };

const xml = xmljs.js2xml(json, { compact: true, spaces: 2 });
console.log(xml);
// <person>
//   <name>Alice</name>
//   <age>30</age>
//   <hobbies>
//     <hobby>reading</hobby>
//     <hobby>coding</hobby>
//   </hobbies>
// </person>

JSON to XML in Python

import json
import xml.etree.ElementTree as ET

def json_to_xml(data, root_tag='root'):
    root = ET.Element(root_tag)
    _build_xml(root, data)
    return ET.tostring(root, encoding='unicode', xml_declaration=False)

def _build_xml(parent, data):
    if isinstance(data, dict):
        for key, val in data.items():
            child = ET.SubElement(parent, key)
            _build_xml(child, val)
    elif isinstance(data, list):
        for item in data:
            child = ET.SubElement(parent, 'item')
            _build_xml(child, item)
    else:
        parent.text = str(data)

data = {'name': 'Alice', 'age': 30}
print(json_to_xml(data, 'person'))
# <person><name>Alice</name><age>30</age></person>

Key Mapping Challenges

Using xmltodict in Python

import xmltodict
import json

# XML to JSON
xml = '<person><name>Alice</name><age>30</age></person>'
data = xmltodict.parse(xml)
print(json.dumps(data, indent=2))

# JSON to XML
data = {'person': {'name': 'Alice', 'age': '30'}}
xml = xmltodict.unparse(data, pretty=True)
print(xml)

FAQ