libxml2-wasm

Why Choose Another XML Library?

When comparing the previous two main approaches — pure JavaScript implementation and traditional C implementation binding — WebAssembly offers a unique combination of advantages. It provides excellent performance while maintaining the best compatibility with modern JavaScript runtimes.

	Javascript Implementation	Traditional C Binding	WebAssembly
Parsing Speed	Average1	Fast	Fast
C/C++ Toolchain at Runtime	Not required	Required2	Not Required
Prebuilt Binaries	N/A	One for each OS / Runtime / Arch	Universal for all
Prebuilt Binary Compatibility	N/A	May be broken across libc versions	Very Good
Browser Compatibility	Yes	No	Yes

Documentation

https://jameslan.github.io/libxml2-wasm/index.html

Supported Environments

Due to the usage of WebAssembly, ES module and top level await etc, this library requires the minimum version of the following environments,

Environment	Version
Node.js	v16+
Chrome	V89+
Edge	V89+
Safari	v15+

Features

• Parsing & Querying
• Validating
• Modifying
• Serializing
• XInclude and XSD include/import (experimental)

Getting started

Install libxml2-wasm package:

npm i libxml2-wasm

libxml2-wasm is an ES module, the import process differs between ES modules and CommonJS modules.

From ES Module

import fs from 'node:fs';
import { XmlDocument } from 'libxml2-wasm';
const doc1 = XmlDocument.fromString('<note><to>Tove</to></note>');
const doc2 = XmlDocument.fromBuffer(fs.readFileSync('doc.xml'));
doc1.dispose();
doc2.dispose();

From CommonJS

const fs = require('node:fs');
import('libxml2-wasm').then(({ XmlDocument }) => {
    const doc1 = XmlDocument.fromString('<note><to>Tove</to></note>');
    const doc2 = XmlDocument.fromBuffer(fs.readFileSync('doc.xml'));
    doc1.dispose();
    doc2.dispose();
});

IMPORTANT: dispose() is required to avoid memory leak.

For more detail, see the Doc.

Footnotes

1. The performance of different XML libraries can vary significantly. For more information, refer to the benchmark provided. ↩

2. The requirement of a C/C++ toolchain at runtime can be waived if prebuilt binaries are available. ↩