phantomjs not waiting for "full" page load

I'm using PhantomJS v1.4.1 to load some web pages. I don't have access to their server-side, I just getting links pointing to them. I'm using obsolete version of Phantom because I need to support Adobe Flash on that web pages.

The problem is many web-sites are loading their minor content async and that's why Phantom's onLoadFinished callback (analogue for onLoad in HTML) fired too early when not everything still has loaded. Can anyone suggest how can I wait for full load of a webpage to make, for example, a screenshot with all dynamic content like ads?

Another approach is to just ask PhantomJS to wait for a bit after the page has loaded before doing the render, as per the regular rasterize.js example, but with a longer timeout to allow the JavaScript to finish loading additional resources:

page.open(address, function (status) {
    if (status !== 'success') {
        console.log('Unable to load the address!');
        phantom.exit();
    } else {
        window.setTimeout(function () {
            page.render(output);
            phantom.exit();
        }, 1000); // Change timeout as required to allow sufficient time 
    }
});

I would rather periodically check for document.readyState status (https://developer.mozilla.org/en-US/docs/Web/API/document.readyState). Although this approach is a bit clunky, you can be sure that inside onPageReady function you are using fully loaded document.

var page = require("webpage").create(),
    url = "http://example.com/index.html";

function onPageReady() {
    var htmlContent = page.evaluate(function () {
        return document.documentElement.outerHTML;
    });

    console.log(htmlContent);

    phantom.exit();
}

page.open(url, function (status) {
    function checkReadyState() {
        setTimeout(function () {
            var readyState = page.evaluate(function () {
                return document.readyState;
            });

            if ("complete" === readyState) {
                onPageReady();
            } else {
                checkReadyState();
            }
        });
    }

    checkReadyState();
});

Additional explanation:

Using nested setTimeout instead of setInterval prevents checkReadyState from "overlapping" and race conditions when its execution is prolonged for some random reasons. setTimeout has a default delay of 4ms (https://stackoverflow.com/a/3580085/1011156) so active polling will not drastically affect program performance.

document.readyState === "complete" means that document is completely loaded with all resources (https://html.spec.whatwg.org/multipage/dom.html#current-document-readiness).

You could try a combination of the waitfor and rasterize examples:

/**
 * See https://github.com/ariya/phantomjs/blob/master/examples/waitfor.js
 * 
 * Wait until the test condition is true or a timeout occurs. Useful for waiting
 * on a server response or for a ui change (fadeIn, etc.) to occur.
 *
 * @param testFx javascript condition that evaluates to a boolean,
 * it can be passed in as a string (e.g.: "1 == 1" or "$('#bar').is(':visible')" or
 * as a callback function.
 * @param onReady what to do when testFx condition is fulfilled,
 * it can be passed in as a string (e.g.: "1 == 1" or "$('#bar').is(':visible')" or
 * as a callback function.
 * @param timeOutMillis the max amount of time to wait. If not specified, 3 sec is used.
 */
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 page = require('webpage').create(), system = require('system'), address, output, size;

if (system.args.length < 3 || system.args.length > 5) {
    console.log('Usage: rasterize.js URL filename [paperwidth*paperheight|paperformat] [zoom]');
    console.log('  paper (pdf output) examples: "5in*7.5in", "10cm*20cm", "A4", "Letter"');
    phantom.exit(1);
} else {
    address = system.args[1];
    output = system.args[2];
    if (system.args.length > 3 && system.args[2].substr(-4) === ".pdf") {
        size = system.args[3].split('*');
        page.paperSize = size.length === 2 ? {
            width : size[0],
            height : size[1],
            margin : '0px'
        } : {
            format : system.args[3],
            orientation : 'portrait',
            margin : {
                left : "5mm",
                top : "8mm",
                right : "5mm",
                bottom : "9mm"
            }
        };
    }
    if (system.args.length > 4) {
        page.zoomFactor = system.args[4];
    }
    var resources = [];
    page.onResourceRequested = function(request) {
        resources[request.id] = request.stage;
    };
    page.onResourceReceived = function(response) {
        resources[response.id] = response.stage;
    };
    page.open(address, 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);
        }
    });
}

Here is a solution that waits for all resource requests to complete. Once complete it will log the page content to the console and generate a screenshot of the rendered page.

Although this solution can serve as a good starting point, I have observed it fail so it's definitely not a complete solution!

I didn't have much luck using document.readyState.

I was influenced by the waitfor.js example found on the phantomjs examples page.

var system = require('system');
var webPage = require('webpage');

var page = webPage.create();
var url = system.args[1];

page.viewportSize = {
  width: 1280,
  height: 720
};

var requestsArray = [];

page.onResourceRequested = function(requestData, networkRequest) {
  requestsArray.push(requestData.id);
};

page.onResourceReceived = function(response) {
  var index = requestsArray.indexOf(response.id);
  if (index > -1 && response.stage === 'end') {
    requestsArray.splice(index, 1);
  }
};

page.open(url, function(status) {

  var interval = setInterval(function () {

    if (requestsArray.length === 0) {

      clearInterval(interval);
      var content = page.content;
      console.log(content);
      page.render('yourLoadedPage.png');
      phantom.exit();
    }
  }, 500);
});