How to verify html DIV's width and height on server side? - html

I was wondering if it's possible to verify a DIV's width and height on server side (PHP) without running any browser?
It seems it's not possible without writing a parser, which is no worth.
One Rube Goldberg way I could think of is, convert that DIV into html (using html tidy), then into PDF and then get the size. Highly inefficient. Even in that case I'm not sure how I'd set PDF page size.
The real practical problem is that I want to confirm the size of adverts created on client side. Users are charged based on size only. What could be alternate ways to verify dimensions? Don't Google and adready (www.adready.com) do something like this already?
Edited: These ads are template based and customer changes only few TEXT variables.

It's definitely not possible. There is a plethora of client-side settings influencing the ways a page is rendered that you can't control. The only thing you could do is use a service like BrowserShots (http://browsershots.org) to make screenshots of what your sites look like in the most common browsers.
Edit: What you could do, on second thought, is write a JavaScript that determines the size of the elements - easy enough using a cross-browser framework like prototype using .getDimensions() - and send that data back to the server using Ajax. You would have to generate a unique id to identify the callcacks but this should be a good way. It seems a bit of an overkill to use this in a production environment but there are much more resource-consuming Javascripts built into sites every day.

Related

Auditing unused CSS on complex web pages

I know there are several tools available to find unused CSS on a static web page. But in most real world scenarios I encounter, a lot of the CSS is used after some or the other interaction on the page, maybe a new modal opening up or an options popup etc.
In such scenarios, what would you suggest? How do I keep a tab on my ever-growing render blocking CSS?
The only way I guess one could do that is by running regular unused-css-detector type tools in conjunction with Selenium - test known interactions and see whats left unused. But a big assumption here is that I'd need to know all interactions on my page which could use new CSS. Is there a way to achieve my goal without making this assumption?
In an ideal world, I'd be able to post-back all CSS used by a visitor's browser on my page to my server. Then I'd collect data over a month, aggregate, and get a pretty accurate idea about actual unused CSS.
Any good ideas?
I am the author of a tool that is aiming at doing what you are describing. Everywhere I worked, the CSS is this "append-only" thing that is too risky, too time-consuming to clean up. And even when you try, the ROI is so low that it not worth it.
So I am working on a tool that is very similar to what you are describing. The goal is to bring confidence on what can be removed, and to actually do it automatically by submitting pull requests.
A snippet of JavaScript is running in the browser and sends reports of what is being used to a server. Once enough data is accumulated to build some "confidence score", it can create Pull Request automatically to remove selectors that are actually not used.
It is still very early stage, but you are welcome to try it and give some feedback about it.
https://www.bleachcss.com/

Is there a simpler option to "nest" or embed content without using iFrames or JavaScript to generate content?

I've read some related articles (like making JavaScript generated content possible for search engines to index), but what I'd like to know, is there a simpler option to embed content from another site? Without the use of iFrames.
What I'd like to achieve in the end is to create some sort of repository for content and serve that to different sites/clients.
For instance (and this is pseudo-coded):
<dl><dt>Date of birth</dt><dd><span src="http://myserver.com/get.aspx?value=dob&userid=102" /></dd></dl>
where the span src is ofcourse not valid or working, but I'd like something similar. First, and foremost, it should be "codable" for non-technical users and second it should be indexable by search spiders.
Now the question: is there something for this?
EDIT:
The sites who need to "recieve" this data I keep aren't mine. Like I've said in a comment Facebook being the worst example I can choose but the principle remains: I'd like to create 1 source of information which you keep at my server and let other party's feed from this content so you'll only need to update some generic information only once.
Now the question: is there something for this?
Only using a server-side language like PHP, or using Server Side Includes.
The downside to these methods is that the rendering of your page becomes dependent on the remote page's availability and rendering speed. If the remote page goes down, so does yours.
Therefore, some kind of caching should be used when including 3rd party content from server side... And it gets complicated then, as well, so it doesn't match the simpler solution you are looking for.
I know iframes have their disadvantages, but if you can live with them, they are still the simplest way of doing this.
um... How simple are you looking for? I mean... In your example, if you change "SPAN" to "IFRAME" you'll have working code.
I think the real problem is how get it indexable by seach spiders, but that request basically translates to "How can my site get credit for other people's work --- with absolutely no effort on my part...."

How can I save a webpage as an image in my rails app?

In my rails app I have a need to save some webpages and display them to the user as images. For example, how would I save www.google.com as an image?
There is a command line utility called CutyCapt that is using the WebKit-Rendering engine to render HTML-Pages into various image formats. Maybe this is for you?
http://cutycapt.sourceforge.net/
Prohibitively difficult to do in pure Ruby, so you'd want to use an external service for this. Browsershots does it, for example, and it looks like they have an api, although I haven't used it myself. Maybe someone else can chime in with alternative but similar services.
You'll also want to read up on delayed_job or something similar, to make sure you're accessing those page images as a background task and that it doesn't interfere with your actual application.
You can't do it easily (probably can't do it at all).
Each page is just a text - html data. The view you want to make an image of is a rendered page. Browser renders the page using tonns of techniques like html parsing, javascript parsing, css parsing, font rendering, etc.. To make the screenshot of google page - you would need to do all the rendering somewhere in memory and then take a screenshot of rendered page.
That task is almost impossible (there is nothing fully impossible).
If you are really eager to donate tonns of time to accomplish that task - you should do this steps:
1) Find some opensource rendering engine. Firefox would do.
2) Find some way to communicate between ruby-on-rails and that engine.
3) Wire it all together and see the results.
However, I see steps 1 and 2 as nearly impossible.
Firefox addon:
https://addons.mozilla.org/en-US/firefox/addon/1146/

HTML printing - what methods are there to make an html based printout? What are the pros and cons?

I have a report I need to print out in an application I'm usually doing maintenance for. My question, which interests me beyond the scope of this task is, what are the ways to format an HTML page for printing? What are the pros and cons of each?
Note that the page is meant only to be printed. I'm not asking about an HTML page that looks ok also when printed.
Generally speaking, I know I can either rely heavily on <table>s or on <div>s, but I don't know which way to go.
I would also appreciate some resources to get me started, or to help with known problems, in any method you suggest.
Thanks,
Asaf
As you can certainly see, printing and web presentation are two different creatures. The main issue is the bounds of the printed page, which does not exist in a web page. Even if you think you have a page laid out in a manner that will fit a printed page, then you need to deal with the fact that the font you are using may not work or scale correctly on the user's printer.
I know of three ways to deal with this issue:
Use fixed-sized fonts (like Courier), limit yourself to an 80 column width, and only use font characters: meaning use something like asterisks for borders, etc. This is VERY old school - your reports look simple and old and plain. But, they will always print they way you intended.
Convert your report to an image. Images can be made to confirm to a specific size which can fit on a page. However, you can still have issues due to printer margin settings.
Let another application do the work for you. What I mean by this is put your report into a PDF or a spreadsheet. Both PHP and Perl have easy to use modules for creating a PDF - with no licensing needed. Perl has a fantastic spreadsheet module. This route takes a little learning up front, but frees you from having to be an expert on printing (which can be a real pain).
In case you DO want to have a page that also looks good when viewed in a browser, consider multiple stylesheets for different medias.

Best way to include/update common elements on a small html based site

I know that with a large site you would want to separate footers, menus, etc so that updating that file would push the update out to every page that contains the item.
Is the same recommended for a small site made purely in HTML/CSS, or is it simpler/easier/standard to code out the menu in each page and update each page when a change is needed?
I don't necessarily want to bring in PHP or etc onto this website, but the ease of updating menus would be nice. Any other suggestions? I've heard Server Side Includes might be one option... is that considered "pure html" or is more required to be set up on the server?
Thanks!
Unless you've got a site consisting of one page, do yourself a favor and have some separate files with your header/footer/other repeated elements.
That way you only have to make one change and its done. No matter how meticulous you think you are, you will inevitably forget a page somewhere on an update any other way. Its a human thing.
If its "just" HTML, and you're not using a server-side language, then you are correct in that you'll want to use server side includes. Check with your host to see if it will process SSI on regular *.htm/*.html files or if you need to use the *.shtm/*.shtml extension.
Server side includes isn't html, but it's not really coding either. It's probably your best option if you don't want to get PHP or some other coding solution involved.
It's mainly just a function of the webserver that you are using, and whether it's enabled for the site.
Here's a tutorial on them for Apache.
Here's documentation for IIS.
There are tons of different ways to approach this problem, but ultimately if you want to make changes on your side and have them reflected in lots of pages you're going to have to have either some kind of server side processing, which means PHP or JSP or something along those lines, or you're going to have to have some sort of process that generates your site statically updating lots of repeated items wherever they occur, but ultimately that would just be a compile time solution that's equivalent to some other server side approach.
If you're comfortable working in Java / JSP, then simple JSP includes might do everything you need. If they don't, then you could go for a full blown Portlets API application. I'm sure other languages have equally valid approaches, so ultimately its decideding what you're most comfortable with.
Server side includes would be "pure HTML" from the browser's standpoint, but then so would PHP.
If you didn't want to Server Side Includes, you could dynamically build them using JavaScript or a library such as jQuery, and just include a .js file in each of your pages.
If it's really small / mostly text-based content, you could just have one page with hidden DIVs that are switched in. Then it'll also be very snappy and self-contained if someone wants to view it offline.
It is very easy to do this with php. This is some sample index.php page i've built:
http://pastebay.com/51887
And for example in "includes/navigation.php" i have this:
http://pastebay.com/51888
So in everypage you have just put that from first link and when you want to edit navigation, just edit "includes/navigation.php". :)