server.js

/*
 * Simple OPML parsing example for now
 */
var OpmlParser = require('opmlparser');

var opmlparser = new OpmlParser()
    , index = {};

fs = require('fs');
var xml = fs.readFileSync('ITIL-V3Core.opml');

opmlparser.on('error', done);
opmlparser.once('readable', function () {
    console.log('This OPML is entitled: "%s"', this.meta.title);
});
opmlparser.on('readable', function() {
    var outline;

    while (outline = this.read()) {
        index[outline['#id']] = outline;
    }
});
opmlparser.on('end', function () {
    console.log('Here\'s my hierarchy.');

    var stack = Object.keys(index).reduce(function (stack, id) {
        var outline = index[id]
            , i
            , children;
        if (stack[0]['#id'] === outline['#parentid']) {
            stack[0].children || (stack[0].children = {});
            stack[0].children[id] = outline;
        }
        else if (stack[0].children && outline['#parentid'] in stack[0].children) {
            stack.unshift(stack[0].children[outline['#parentid']]);
            stack[0].children || (stack[0].children = {});
            stack[0].children[id] = outline;
        }
        else {
            // unwind the stack as much as needed
            for (i = stack.length - 1; i >= 0; i--) {
                children = stack.shift();
                stack[0].children[children['#id']] = children;
                if (stack[0]['#id'] === outline['#parentid']) {
                    stack[0].children[id] = outline;
                    break;
                }
            }
        }
        return stack;
    }, [ { 'text': 'root', '#id': 0, children: {} } ]);

    console.log(inspect(stack[0]));
    console.log('All done.');
});

opmlparser.end(xml);

function done (err) {
    if (err) {
        console.log(err, err.stack);
        return process.exit(1);
    }
    process.exit();
}

function inspect (obj) {
    return require('util').inspect(obj, null, 10, true);
}