Applying DOM Manipulations to HTML and saving the result? - javascript

I have about 100 static HTML pages that I want to apply some DOM manipulations to. They all follow the same HTML structure. I want to apply some DOM manipulations to each of these files, and then save the resulting HTML.
These are the manipulations I want to apply:
# [start]
$("h1.title, h2.description", this).wrap("<hgroup>");
if ( $("h1.title").height() < 200 ) {
$("div.content").addClass('tall');
}
# [end]
# SAVE NEW HTML
The first line (.wrap()) I could easily do with a find and replace, but it gets tricky when I have to determine the calculated height of an element, which can't be easily be determined sans-JavaScript.
Does anyone know how I can achieve this? Thanks!

While the first part could indeed be solved in "text mode" using regular expressions or a more complete DOM implementation in JavaScript, for the second part (the height calculation), you'll need a real, full browser or a headless engine like PhantomJS.
From the PhantomJS homepage:
PhantomJS is a command-line tool that packs and embeds WebKit.
Literally it acts like any other WebKit-based web browser, except that
nothing gets displayed to the screen (thus, the term headless). In
addition to that, PhantomJS can be controlled or scripted using its
JavaScript API.
A schematic instruction (which I admit is not tested) follows.
In your modification script (say, modify-html-file.js) open an HTML page, modify it's DOM tree and console.log the HTML of the root element:
var page = new WebPage();
page.open(encodeURI('file://' + phantom.args[0]), function (status) {
if (status === 'success') {
var html = page.evaluate(function () {
// your DOM manipulation here
return document.documentElement.outerHTML;
});
console.log(html);
}
phantom.exit();
});
Next, save the new HTML by redirecting your script's output to a file:
#!/bin/bash
mkdir modified
for i in *.html; do
phantomjs modify-html-file.js "$1" > modified/"$1"
done

I tried PhantomJS as in katspaugh's answer, but ran into several issues trying to manipulate pages. My use case was modifying the static html output of Doxygen, without modifying Doxygen itself. The goal was to reduce delivered file size by remove unnecessary elements from the page, and convert it to HTML5. Additionally I also wanted to use jQuery to access and modify elements more easily.
Loading the page in PhantomJS
The APIs appear to have changed drastically since the accepted answer. Additionally, I used a different approach (derived from this answer), which will be important in mitigating one of the major issues I encountered.
var system = require('system');
var fs = require('fs');
var page = require('webpage').create();
// Reading the page's content into your "webpage"
// This automatically refreshes the page
page.content = fs.read(system.args[1]);
// Make all your changes here
fs.write(system.args[2], page.content, 'w');
phantom.exit();
Preventing JavaScript from Running
My page uses Google Analytics in the footer, and now the page is modified beyond my intention, presumably because javascript was run. If we disable javascript, we can't actually use jQuery to modify the page, so that isn't an option. I've tried temporarily changing the tag, but when I do, every special character is replaced with an html-escaped equivalent, destroying all javascript code on the page. Then, I came across this answer, which gave me the following idea.
var rawPageString = fs.read(system.args[1]);
rawPageString = rawPageString.replace(/<script type="text\/javascript"/g, "<script type='foo/bar'");
rawPageString = rawPageString.replace(/<script>/g, "<script type='foo/bar'>");
page.content = rawPageString;
// Make all your changes here
rawPageString = page.content;
rawPageString = rawPageString.replace(/<script type='foo\/bar'/g, "<script");
Adding jQuery
There's actually an example on how to use jQuery. However, I thought an offline copy would be more appropriate. Initially I tried using page.includeJs as in the example, but found that page.injectJs was more suitable for the use case. Unlike includeJs, there's no <script> tag added to the page context, and the call blocks execution which simplifies the code. jQuery was placed in the same directory I was executing my script from.
page.injectJs("jquery-2.1.4.min.js");
page.evaluate(function () {
// Make all changes here
// Remove the foo/bar type more easily here
$("script[type^=foo]").removeAttr("type");
});
fs.write(system.args[2], page.content, 'w');
phantom.exit();
Putting it All Together
var system = require('system');
var fs = require('fs');
var page = require('webpage').create();
var rawPageString = fs.read(system.args[1]);
// Prevent in-page javascript execution
rawPageString = rawPageString.replace(/<script type="text\/javascript"/g, "<script type='foo/bar'");
rawPageString = rawPageString.replace(/<script>/g, "<script type='foo/bar'>");
page.content = rawPageString;
page.injectJs("jquery-2.1.4.min.js");
page.evaluate(function () {
// Make all changes here
// Remove the foo/bar type
$("script[type^=foo]").removeAttr("type");
});
fs.write(system.args[2], page.content, 'w');
phantom.exit();
Using it from the command line:
phantomjs modify-html-file.js "input_file.html" "output_file.html"
Note: This was tested and working with PhantomJS 2.0.0 on Windows 8.1.
Pro tip: If speed matters, you should consider iterating the files from within your PhantomJS script rather than a shell script. This will avoid the latency that PhantomJS has when starting up.

you can get your modified content by $('html').html() (or a more specific selector if you don't want stuff like head tags), then submit it as a big string to your server and write the file server side.

Related

getting OnLoad HTML/DOM for an HTML page in PHP

I am trying to get the HTML (ie what you see initially when the page completes loading) for some web-page URI. Stripping out all error checking and assuming static HTML, it's a single line of code:
function GetDisplayedHTML($uri) {
return file_get_contents($uri);
}
This works fine for static HTML, and is easy to extend by simple parsing, if the page has static file dependencies/references. So tags like <script src="XXX">, <a href="XXX">, <img src="XXX">, and CSS, can also be detected and the dependencies returned in an array, if they matter.
But what about web pages where the HTML is dynamically created using events/AJAX? For example suppose the HTML for the web page is just a brief AJAX-based or OnLoad script that builds the visible web page? Then parsing alone won't work.
I guess what I need is a way from within PHP, to open and render the http response (ie the HTML we get at first) via some javascript engine or browser, and once it 'stabilises', capture the HTML (or static DOM?) that's now present, which will be what the user's actually seeing.
Since such a webpage could continually change itself, I'd have to define "stable" (OnLoad or after X seconds?). I also don't need to capture any timer or async event states (ie "things set in motion that might cause web page updates at some future time"). I only need enough of the DOM to represent the static appearance the user could see, at that time.
What would I need to do, to achieve this programmatically in PHP?
To render page with JS you need to use some browser. PhantomJS was created for tasks like this. Here is simple script to run with Phantom:
var webPage = require('webpage');
var page = webPage.create();
var system = require('system');
var args = system.args;
if (args.length === 1) {
console.log('First argument must be page URL!');
} else {
page.open(args[1], function (status) {
window.setTimeout(function () { //Wait for scripts to run
var content = page.content;
console.log(content);
phantom.exit();
}, 500);
});
}
It returns resulting HTML to console output.
You can run it from console like this:
./phantomjs.exe render.js http://yandex.ru
Or you can use PHP to run it:
<?php
$path = dirname(__FILE__);
$html = shell_exec($path . DIRECTORY_SEPARATOR . 'phantomjs.exe render.js http://phantomjs.org/');
echo htmlspecialchars($html);
My PHP code assumes that PhantomJS executable is in the same directory as PHP script.

PHP Get Rendered Javascript Page

I'm developing application using AngularJS. Everything seems to be nice until I meet something that leads me to headache: SEO.
From many references, I found out that AJAX content crawled and indexed by Google bot or Bing bot 'is not that easy' since the crawlers don't render Javascript.
Currently I need a solution using PHP. I use PHP Slim Framework so my main file is index.php which contains function to echo the content of my index.html. My question is:
Is it possible to make a snapshot of rendered Javascript in HTML?
My strategy is:
If the request query string contains _escaped_fragment_, the application will generate a snapshot and give that snapshot as response instead of the exact file.
Any help would be appreciated. Thanks.
After plenty of times searching and researching, I finally managed to solve my problem by mixing PHP with PhantomJS (version 2.0). I use exec() function in PHP to run phantomJS and create Javascript file to take get the content of the targeted URL. Here are the snippets:
index.php
// Let's assume that you have a bin folder under your root folder directory which contains phantomjs.exe and content.js
$script = __DIR__ ."/bin/content.js";
$target = "http://www.kincir.com"; // target URL
$cmd = __DIR__."/bin/phantomjs.exe $script $target";
exec($cmd, $output);
return implode("", $output);
content.js
var webPage = require('webpage');
var system = require('system');
var page = webPage.create();
var url = system.args[1]; // This will get the second argument from $cmd, in this example, it will be the value of $target on index.php which is "http://www.kincir.com"
page.open(url, function (status) {
page.onLoadFinished = function () { // Make sure to return the content of the page once the page is finish loaded
var content = page.content;
console.log(content);
phantom.exit();
};
});
I recently published a project that gives PHP access to a browser. Get it here: https://github.com/merlinthemagic/MTS. It also relies on PhantomJS.
After downloading and setup you would simply use the following code:
$myUrl = "http://www.example.com";
$windowObj = \MTS\Factories::getDevices()->getLocalHost()->getBrowser('phantomjs')->getNewWindow($myUrl);
//now you can either retrive the DOM and parse it, like this:
$domData = $windowObj->getDom();
//this project also lets you manipulate the live page. Click, fill forms, submit etc.

PhantomJS how to render javascript in html string

I'm trying to get PhantomJS to take an html string and then have it render the full page as a browser would (including execution of any javascript in the page source). I need the resulting html result as a string. I have seen examples of page.open which is of no use since I already have the page source in my database.
Do I need to use page.open to trigger the javascript rendering engine in PhantomJS? Is there anyway to do this all in memory (ie.. without page.open making a request or reading/writing html source from/to disk?
I have seen a similar question and answer here but it doesn't quite solve my issue. After running the code below, nothing I do seems to render the javascript in the html source string.
var page = require('webpage').create();
page.setContent('raw html and javascript in this string', 'http://whatever.com');
//everything i've tried from here on doesn't execute the javascript in the string
--------------Update---------------
Tried the following based on the suggestion below but this still does not work. Just returns the raw source that I supplied with no javascript rendered.
var page = require('webpage').create();
page.settings.localToRemoteUrlAccessEnabled = true;
page.settings.webSecurityEnabled = false;
page.onLoadFinished = function(){
var resultingHtml = page.evaluate(function() {
return document.documentElement.innerHTML;
});
console.log(resultingHtml);
//console.log(page.content); // this didn't work either
phantom.exit();
};
page.url = input.Url;
page.content = input.RawHtml;
//page.setContent(input.RawHtml, input.Url); //this didn't work either
The following works
page.onLoadFinished = function(){
console.log(page.content); // rendered content
};
page.content = "your source html string";
But you have to keep in mind that if you set the page from a string, the domain will be about:blank. So if the html loads resources from other domains, then you should run PhantomJS with the --web-security=false --local-to-remote-url-access=true commandline options:
phantomjs --web-security=false --local-to-remote-url-access=true script.js
Additionally, you may need to wait for the completion of the JavaScript execution which might be not be finished when PhantomJS thought it finished. Use either setTimeout() to wait a static amount of time or waitFor() to wait for a specific condition on a page. More robust ways to wait for a full page are given in this question: phantomjs not waiting for “full” page load
The setTimeout made it work even though I'm not excited to wait a set amount of time for each page. The waitFor approach that is discussed here doesn't work since I have no idea what elements each page might have.
var system = require('system');
var page = require('webpage').create();
page.setContent(input.RawHtml, input.Url);
window.setTimeout(function () {
console.log(page.content);
phantom.exit();
}, input.WaitToRenderTimeInMilliseconds);
Maybe not the answer you want, but using PhantomJsCloud.com you can do it easily, Here's an example: http://api.phantomjscloud.com/api/browser/v2/a-demo-key-with-low-quota-per-ip-address/?request={url:%22http://example.com%22,content:%22%3Ch1%3ENew%20Content!%3C/h1%3E%22,renderType:%22png%22,scripts:{domReady:[%22var%20hiDiv=document.createElement%28%27div%27%29;hiDiv.innerHTML=%27Hello%20World!%27;document.body.appendChild%28hiDiv%29;window._pjscMeta.scriptOutput={Goodbye:%27World%27};%22]},outputAsJson:false} The "New Content!" is the content that replaces the original content, and the "Hello World!" is placed in the page by a script.
If you want to do this via normal PhantomJs, you'll need to use the injectJs or includeJs functions, after the page content is loaded.

Firefox addon SDK and DOM manipulation problems

I'm trying to get to grips with the Firefox addon SDK (previously known as Jetpack from what I understand), but I'm having problems working with the DOM.
I need to iterate over all of the text nodes in the DOM when a web page loads and make changes to some of the strings that they contain. I've posted a simplified version of what I'm doing below (new to Javascript, so forgive me any oddities).
// test.js
function parseElement(Element)
{
if (Element == null)
return;
var i = 0;
var Result = false;
if (Element.hasChildNodes)
{
var children = Element.childNodes;
while (i <= children.length - 1)
{
var child = children.item(i);
parseElement(child);
i++;
}
}
if (Element.nodeType == 3)
{
// For testing - see what the text node contains
alert(Element.nodeValue);
Result = true;
}
return Result;
}
window.addEventListener("load", function load(event)
{
window.removeEventListener("load", load, false);
parseElement(document.body);
}
When I create a basic HTML document:
<!-- test.html -->
<html>
<head>
<script type="text/javascript" src="test.js"></script>
</head>
<body>
<b>hello world</b>
<p>foo</p>
<i>test</i>
</body>
</html>
...include this Javascript file in the HEAD section then open it in Firefox, the "alert" displays 6 dialog boxes containing:
1) "hello world"
2) blank -> no visible characters, just a newline
3) "foo"
4) blank -> no visible characters, just a newline
5) "test"
6) blank -> no visible characters, just a newline
Exactly what I would expect to see.
The problem arises when I create an addon and use test.js as a page-mod Content Script from my main.js file (modified to remove the "addEventListener" part). When I use "cfx run" to start Firefox with my addon installed, then open the same HTML document (with the "script" part for the test.js file commented), the alerts do not display at all.
So that's the first puzzle. But having also navigated to other web pages - for example, a YouTube video page - the alert DOES display several dialogs, but they include very strange strings, mostly the content of script tags:
EDIT I don't have enough reputation to embed an image, so here's a link instead showing the sort of thing I mean instead: http://img46.imageshack.us/img46/5994/mtpd.jpg
And again, the text I would expect to see is absent.
Apologies for some of the redundancy below, but just to be clear: this is my main.js:
main.js
var data = require("sdk/self").data;
var data = require("sdk/self").data;
exports.main = function()
{
pageMod.PageMod({
include: "*",
contentScriptFile: [data.url("test.js")]
});
}
And the modified version of the Javascript file is identical to the "test.js" listing above, but for the end part:
test.js
<snip>
...
return Result;
}
parseElement(document.body);
I've included my project files (if I can call them that) in a zip if it makes things easier to visualise: http://www.mediafire.com/?774iprbngtlgkcp
I've tried changing
parseElement(document.body);
to
parseElement(unsafeWindow.document.body);
in case it makes any difference, but the outcome is identical.
So I'm very puzzled about what's happening. I can't understand why the test.js file isn't picking out the text nodes (and only the text nodes) from the DOM when I use it as part of an addon, but does exactly what I would anticipate when included as a script in a HTML document. Can anyone shed any light on this?
Thank you in advance.
Errors in your lib code and contentScripts are usually logged to the Error Console. Check what is printed there. Also see the SDK console module.
Your page-mod won't run because by default page-mods will run only after the load event.
See the contentScriptWhen documentation.
script tags actually often have a text-node child containing the inline script source. So it is absolutely normal that those are enumerated as well.
For some discussion about walking tree nodes, see: getElementsByTagName() equivalent for textNodes
However, if you're after the text of specific ids/classes, consider using document.querySelector/.querySelectorAll, or if you're after nodes that have a specific XPath, use document.evaluate. This very likely will be a lot faster.
Other than that, I cannot really tell what exactly your remaining issues are and what you're trying to achieve in the first place exactly, so I cannot advice on that.
You wondered that
I've discovered that my add-on is NOT executed when a document is
accessed via File->Open File.
That is by design. At match-pattern, it says that
A single asterisk matches any URL with an http, https, or ftp scheme.
For other schemes like file, resource, or data, use a scheme followed
by an asterisk, as below.
You can use the regular expression /.*/ to match all sites and all schemas.

Inject local .js file into a webpage?

I'd like to inject a couple of local .js files into a webpage. I just mean client side, as in within my browser, I don't need anybody else accessing the page to be able to see it. I just need to take a .js file, and then make it so it's as if that file had been included in the page's html via a <script> tag all along.
It's okay if it takes a second after the page has loaded for the stuff in the local files to be available.
It's okay if I have to be at the computer to do this "by hand" with a console or something.
I've been trying to do this for two days, I've tried Greasemonkey, I've tried manually loading files using a JavaScript console. It amazes me that there isn't (apparently) an established way to do this, it seems like such a simple thing to want to do. I guess simple isn't the same thing as common, though.
If it helps, the reason why I want to do this is to run a chatbot on a JS-based chat client. Some of the bot's code is mixed into the pre-existing chat code -- for that, I have Fiddler intercepting requests to .../chat.js and replacing it with a local file. But I have two .js files which are "independant" of anything on the page itself. There aren't any .js files requested by the page that I can substitute them for, so I can't use Fiddler.
Since your already using a fiddler script, you can do something like this in the OnBeforeResponse(oSession: Session) function
if ( oSession.oResponse.headers.ExistsAndContains("Content-Type", "html") &&
oSession.hostname.Contains("MY.TargetSite.com") ) {
oSession.oResponse.headers.Add("DEBUG1_WE_EDITED_THIS", "HERE");
// Remove any compression or chunking
oSession.utilDecodeResponse();
var oBody = System.Text.Encoding.UTF8.GetString(oSession.responseBodyBytes);
// Find the end of the HEAD script, so you can inject script block there.
var oRegEx = oRegEx = /(<\/head>)/gi
// replace the head-close tag with new-script + head-close
oBody = oBody.replace(oRegEx, "<script type='text/javascript'>console.log('We injected it');</script></head>");
// Set the response body to the changed body string
oSession.utilSetResponseBody(oBody);
}
Working example for www.html5rocks.com :
if ( oSession.oResponse.headers.ExistsAndContains("Content-Type", "html") &&
oSession.hostname.Contains("html5rocks") ) { //goto html5rocks.com
oSession.oResponse.headers.Add("DEBUG1_WE_EDITED_THIS", "HERE");
oSession.utilDecodeResponse();
var oBody = System.Text.Encoding.UTF8.GetString(oSession.responseBodyBytes);
var oRegEx = oRegEx = /(<\/head>)/gi
oBody = oBody.replace(oRegEx, "<script type='text/javascript'>alert('We injected it')</script></head>");
oSession.utilSetResponseBody(oBody);
}
Note, you have to turn streaming off in fiddler : http://www.fiddler2.com/fiddler/help/streaming.asp and I assume you would need to decode HTTPS : http://www.fiddler2.com/fiddler/help/httpsdecryption.asp
I have been using fiddler script less and less, in favor of fiddler .Net Extensions - http://fiddler2.com/fiddler/dev/IFiddlerExtension.asp
If you are using Chrome then check out dotjs.
It will do exactly what you want!
How about just using jquery's jQuery.getScript() method?
http://api.jquery.com/jQuery.getScript/
save the normal html pages to the file system, add the js files manually by hand, and then use fiddler to intercept those calls so you get your version of the html file

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