phantomjs

function waitFor(testFx, onReady, timeOutMillis) {
    var maxtimeOutMillis = timeOutMillis ? timeOutMillis : 3000, //< Default Max Timout is 3s
        start = new Date().getTime(),
        condition = (typeof(testFx) === "string" ? eval(testFx) : testFx()), //< defensive code
        interval = setInterval(function() {
            if ( (new Date().getTime() - start < maxtimeOutMillis) && !condition ) {
                // If not time-out yet and condition not yet fulfilled
                condition = (typeof(testFx) === "string" ? eval(testFx) : testFx()); //< defensive code
            } else {
                if(!condition) {
                    // If condition still not fulfilled (timeout but condition is 'false')
                    console.log("'waitFor()' timeout");
                    phantom.exit(1);
                } else {
                    // Condition fulfilled (timeout and/or condition is 'true')
                    console.log("'waitFor()' finished in " + (new Date().getTime() - start) + "ms.");
                    typeof(onReady) === "string" ? eval(onReady) : onReady(); //< Do what it's supposed to do once the condition is fulfilled
                    clearInterval(interval); //< Stop this interval
                }
            }
        }, 250); //< repeat check every 250ms
};


var system = require('system'), page = require('webpage').create(), url, output, waitTime, pwidth = 1400, pheight = 700;
console.log(system.args+"\n");

function isInt(value) {
    return !isNaN(value) && parseInt(Number(value)) == value && !isNaN(parseInt(value, 10));
}
if(system.args.length < 4 || system.args.length > 6){
    console.log("Invalid parameter number, Usage: phantomjs script.js url output(e.g file.png) waitTime width(optional) height(option) \n Default size is {width: 1400, height: 700}");
    phantom.exit();
}
url = system.args[1];
output = system.args[2];
waitTime = system.args[3];

if(system.args.length == 6 && isInt(system.args[4]) && isInt(system.args[5])){
    pwidth = system.args[4];
    pheight = system.args[5];
}

var resources = [];
page.onResourceRequested = function(request) {
    resources[request.id] = request.stage;
};
page.onResourceReceived = function(response) {
    resources[response.id] = response.stage;
};

page.viewportSize = { width: pwidth, height: pheight };
page.open(url, function(status) {
    if(status !== 'success'){
        console.log('Unable to load the address!');
        phantom.exit();
    }else{
            waitFor(function() {
                // Check in the page if a specific element is now visible
                for ( var i = 1; i < resources.length; ++i) {
                    if (resources[i] != 'end') {
                        return false;
                    }
                }
                return true;
            }, function() {
               page.render(output);
               phantom.exit();
            }, 10000);
        /*window.setTimeout(function(){
            page.render(output);
            phantom.exit();
        }, waitTime
        );*/
    }
});