save html output of page after execution of the page's javascript

There is a site I am trying to scrape, that first loads an html/js modifies the form input fields using js and then POSTs. How can I get the final html output of the POSTed page?

I tried to do this with phantomjs, but it seems to only have an option to render image files. Googling around suggests it should be possible , but I can't figure out how. My attempt:

var page = require('webpage').create();
var fs = require('fs');
page.open('https://www.somesite.com/page.aspx', function () {
    page.evaluate(function(){

    });

    page.render('export.png');
    fs.write('1.html', page.content, 'w');
    phantom.exit();
});

This code will be used for a client, I can't expect him to install too many packages (nodejs , casperjs etc)

Thanks

the output code you have is correct, but there is an issue with synchronicity. The output lines that you have are being executed before the page is done loading. You can tie into the onLoadFinished Callback to find out when that happens. See full code below.

    var page = new WebPage()
    var fs = require('fs');

    page.onLoadFinished = function() {
      console.log("page load finished");
      page.render('export.png');
      fs.write('1.html', page.content, 'w');
      phantom.exit();
    };

    page.open("http://www.google.com", function() {
      page.evaluate(function() {
      });
    });

When using a site like google, it can be deceiving because it loads so quicker, that you can often execute a screengrab inline like you have it. Timing is a tricky thing in phantomjs, sometimes I test with setTimeout to see if timing is an issue.

When I copied your code directly, and changed the URL to www.google.com, it worked fine, with two files saved:

• 1.html
• export.png

Bear in mind that the files will be written to the location you run the script from, not where your .js file is located