Unlike desktop applications which rarely use “skins”, web applications look ugly and unprofessional w/o a design template. However, building unique design for each project sometimes is just not affordable, especially for back-end, admin and other data analysis and management applications. At the other hand, if you look for free or commercial design templates available, you’ll find nothing but website templates which doesn’t have elements like cascading menus, dialog, grid, form elements and others usually required for an application user interface.

Sad but true, except this little thing: Admintasia 2.1. Powered with jQuery and jQuery IU it has all the elements you need to build rich professional user interfaces.
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Customers and users sometimes ask for an ability to save some reports from web applications to PDF files. It could be very tricky to write PDF directly but as far as you already have those reports on web pages you can add printable views of them and then ability to convert HTML/CSS of the pages to PDF, say with dompdf library.
This way you can hit two targets: add printing of reports and PDF export. Dompdf is still in beta but at least it could work on shared hosting AFAIK.

But what if you need to export web pages with JavaScript canvas elements like Flot charts that are plotted on browser side only? All available solutions require installing executables which is usually problematic on shared hosting.

The solution is PDFmyURL.com/ which you can easily use as a web-service: send GET requests with URL of the page you want to export and get PDF file as a response. The service is based wkhtmltopdf. As you can see, it’s good enough to convert pages with Flot charts:

http://pdfmyurl.com/?url=http://people.iola.dk/olau/flot/examples/basic.html.

You can call the service from JavaScript on your pages or from server-side scripts via any HTTP client library like cURL. All wkhtmltopdf options are supported and could be passed as GET request parameters.

Their free service inserts very small watermark to each page which is usually not a problem. But of course you can upgrade to paid service to remove it.

Modern database driven web sites implement SEO-friendly URLs emulating static directories and files. Switching to such “clean” URLs enables good indexing by search engines, makes URLs more user-friendly and hides the server-side language. For example, this clean URL may refer to the page in some product directory:

http://somesite.com/products/network/router.html

In fact, there is no /products/network folder on the server and no router.html file at all. The page is generated by server script using database query for “network” product category and “router” product. But who calls the script and where it gets the query parameter values?

This technique is usually referred as “URL rewriting”. It allows web server to recognize what information was requested by parsing the URL string. Apache and PHP allow multiple options to implement URL rewriting. So which one is the best?

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The Web community is going crazy about SEO-friendly URLs like http://somesite.com/products/network/router/. Well, it looks much better than a script URL http://somesite.com/products.php?c=network&p=router which may actually serve the page behind the scenes. There are a lot of good articles on how to implement SEO-friendly URLs, for example this one or my own post. But they do not warn the reader about one usual problem: once you have updated your site to handle virtual paths you will probably get a bad surprise:

CSS, image and internal page links are totally broken!

Why? Because those links are usually relative to the page location. The browser has no idea about virtual folders and tries to get files from locations relative to the page URL context. For example, if there is a usual CSS link in the page header:

<link rel="stylesheet" href="style.css" type="text/css" media="screen" />

Then the browser will try to download non-existing file http://somesite.com/products/network/router/style.css and fail silently. No CSS style will be applied.

It’s incredible how many words were spoken about SEO-friendly URLs with almost no word about this relative link problem.
So, what you have to do? Don’t worry, there are multiple solutions available and I’ll try to explain them all.

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