NodeJS end event with while loop

Question

I try to iterate this big xml file using sax, here is the code:

'use strict';
const fs = require('fs');
const sax = require('sax');

let rowsAdded = 0;
let rows = [];
let options = {
    encoding: 'utf8',
    mode: 0o444
};
let strict = true,
feedFile = 'Comments.xml',
saxStream = sax.createStream(strict);
saxStream.on('opentag', node => {
    if(rowsAdded === 5) {
        return saxStream.end();
    }
    // I only need nodes named 'row'
    if(node.name === 'row') {
        rowsAdded++;
        // If the name is 'row' and `attribute` prop exists, push it. 
        if(node.attributes) rows.push(node.attributes);
    }
})
.on('error', () => {
})
.on('end', () => {
    console.log('Done reading:', rowsAdded);
    // If you remove this while loop the above console will called only once
    while(rowsAdded--) {

    }
});
fs.createReadStream(feedFile, options).pipe(saxStream);

The console.log will log Done reading: 5 around 43 times, if I comment out the while loop, it will only console Done reading: 5 once!, am I doing something wrong?, is it a bug?

Answer 1

When you return from saxStream.on('opentag') it means that you finished working on that tag, but the parser continues until it finishes the whole xml.