How do scrape table from the provided website using casperjs? - web-scraping

Question

The final goal is to retrieve stock data in table form from provided broker website and save it to some text file. Here is the code, that I managed to compile so far by reading few tutorials:
var casper = require("casper").create();
var url = 'https://iqoption.com/en/historical-financial-quotes?active_id=1&tz_offset=60&date=2016-12-19-21-59';
var terminate = function() {
this.echo("Exiting ...").exit();
};
var processPage = function() {
var rows = document.querySelectorAll('#mCSB_3_container > table'); //get table from broker site (copy/paste via copy selector in chrome tools)
//var nodes = document.getElementsByClassName('mCSB_container');
this.echo(rows);
this.echo(rows.length);
for (var i = 0; i < rows.length; i++)
{
var cell = rows[i].querySelector('.quotes-table-result__date');
this.echo(cell); //print each cell
}
};
casper.start(url);
casper.waitForSelector('#mCSB_3_container', processPage, terminate);
casper.run();
This code should retrieve the stock price table and print out each cell. However, all what I get is 'undefined', which likely means that I got no objects returned by queryselector call. And please assume that I don't know any web programming (HTML,CSS).

Answer 1

First of all, on problem is that the waitFor wasn't set so good, you have to wait for the rows/cells.
The Nodes you get out on this page are a bit wired,if anybody got a more abstract solution where ChildNodes are better handled that in my solution i would be really interested:
var casper = require('casper').create();
var url = 'https://eu.iqoption.com/en/historical-financial-quotes?active_id=1&tz_offset=60&date=2016-12-19-21-59';
var length;
casper.start(url);
casper.then(function() {
this.waitForSelector('#mCSB_3_container table tbody tr');
});
function getCellContent(row, cell) {
cellText = casper.evaluate(function(row, cell) {
return document.querySelectorAll('table tbody tr')[row].childNodes[cell].innerText.trim();
}, row, cell);
return cellText;
}
casper.then(function() {
var rows = casper.evaluate(function() {
return document.querySelectorAll('table tbody tr');
});
length = rows.length;
this.echo("table length: " + length);
});
// This part can be done nicer, but it's the way it should work ...
casper.then(function() {
for (var i = 0; i < length; i++) {
this.echo("Date: " + getCellContent(i, 0));
this.echo("Bid: " + getCellContent(i, 1));
this.echo("Ask: " + getCellContent(i, 2));
this.echo("Quotes: " + getCellContent(i, 3));
}
});
casper.run();