nxmlpp is simple xml pretty printer for node.js
It's based on https://github.com/isaacs/sax-js and was initially started as variant of https://github.com/isaacs/sax-js/blob/master/examples/pretty-print.js that can be used as library.
var nxmlpp = require('nxmlpp'); console.log(nxmlpp.strPrint('<root><a/><b/></root>'));
nxmlpp [input [output]]
stdin/stdout will be used if some of arguments are omitted.