Getting page rload time using casperjs - casperjs

Question

I'm trying to capture the page load time using casperjs. The page in question is login protected. Here is what I have so far:
var casper = require('casper').create();
// Enter the login page, fill up the form and submit it
casper.start('https://example.net/login', function () {
// Fill the form
this.fill('form[name=signin]', {
'user': 'username',
'passwd': 'password'
}, false);
// Submit the form by clicking the submit button
this.then(function() {
this.click('#sign_in');
});
});
// Now on the loggedin page click the link of page for which response time is needed
casper.then (function() {
var start = Date.now();
this.click ('#pageLink');
// Measure response time of this page
var end = Date.now();
this.echo (end - start);
});
casper.run();
I can pretty much tell it's the wrong approach because I should perhaps wait for the page to load and then capture the end time. But on the casper js documentation page, I did not find any thing that lets me know when the page has loaded fully. Would it make sense to look for the closing tag and see if that has loaded ?

Answer 1

You should use the events : here an example :
(function(){
"use strict";
var s
,e
;
//we use casper events to calculate the time between a http request and its response
casper.on('page.resource.requested', function(requestData, request) {
//console.log("request url " + requestData.url);
s = new Date().getTime();
});
casper.on('page.resource.received', function(response) {
//console.log("response url " + response.url);
e = new Date().getTime();
casper.echo("Time between HTTP request and HTTP response : " + (e-s) + "ms","INFO");
});
})();//then your code
I use an IIFE just to create a scope for var s (start) and e (end).
For what you want, you could do the same with load.started and load.finished.
http://casperjs.readthedocs.org/en/latest/events-filters.html
But there are better tools to do that, Casper isn't that good for monitoring.