Outline of JavaScript | Technology Tales

Self-hosted web analytics tracking

24^th April 2009

It amazes me now to think how little tracking I used to do on my various web "experiments" only a few short years ago. However, there was a time when a mere web counter, perhaps displayed on web pages themselves, was enough to yield some level of satisfaction, or dissatisfaction in many a case. Things have come a long way since then, and we now seem to have analytics packages all around us. In fact, we don't even have to dig into our pockets to get our hands on the means to peruse this sort of information, either.

At this point, I need to admit that I am known to make use of a few simultaneously but thoughts about reducing their number are coming to mind, but there'll be more on that later. Given that this site is hosted using WordPress software, it should come as no surprise that Automattic's own plugin has been set into action to see how things are going. The main focus is on the total number of visits by day, week and month, with a breakdown showing what pages are doing well, together with an indication of how people came to the site and what links they followed while there. Don't go expecting details of your visitors like the software that they are using and the country where they are accessing the site with this minimalist option and satisfaction should head your way.

There is next to no way of discussing the subject of website analytics without mentioning Google's comprehensive offering in the area. You have to admit that it's comprehensive, with perhaps the only bugbear being the lack of live tracking. That need has been addressed very effectively by Woopra, even if its WordPress plugin will not work with IE6. Otherwise, you need the desktop application (being written in Java, it's a cross-platform affair and I have had it going in both Windows and Linux) but that works well too. Apart maybe from the lack of campaigns, Woopra supplies as good as all the information that its main competitor provides. It certainly does what I would need from it.

However, while they can be free as in beer, there are some costs associated with using external services like Google Analytics and Woopra. Their means of tracking your web pages for you is by executing a piece of JavaScript that needs to be added to every page. If you have everything set to use a common header or footer page, that shouldn't be too laborious, especially when there are plugins for publishing platforms like WordPress too. This way of working means that if anyone has JavaScript disabled or decides not to enable JavaScript for the requisite hosts while using the NoScript extension with Firefox, then your numbers are scuppered. Saying that, the same concerns probably any JavaScript code that you may want to execute, but there's another cost again: the calls to external websites can, even with the best attention in the world, slow down the loading of your own pages. When you add in latency caused by servers having to communicate across the web, it is not all about executing JavaScript code.

A self-hosted analytics package would avoid the latter, and I found one recently through Lifehacker: Piwik, formerly known as PHPMyVisites. Usefully, it turns out that it does next to everything that Google Analytics does. While I'd prefer that it used PHP for this, JavaScript is its means of tracking web pages too. Nevertheless, page loading is still faster than with Google Analytics and/or Woopra and Firefox/NoScript users would only have to allow JavaScript for one site too. If you have had experience with installing PHP/MySQL-powered publishing platforms like WordPress, Textpattern and such like, then putting Piwik in place is no ordeal. Though, you may find yourself changing folder access, uploading of the required files, the specification of database credentials and adding an administration user is all fairly standard stuff. After all that, I have the thing tracking this edifice as well as my outdoor activities (hillwalking/cycling/photography) web presence and I cannot say that I have any complaints, so we'll see how it goes from here.

JavaScript: write it yourself or use a library?

3^rd July 2008

I must admit that I have never been a great fan of JavaScript. For one thing, its need to interact with browser objects places you at the mercy of the purveyors of such pieces of software. Debugging is another fine art that can seem opaque to the uninitiated, since the amount and quality of the logging is determined by an interpreter not provided by the language's overseers. All in all, it seems to present a steep and obstacle-strewn learning curve to newcomers. As it happens, I have always found server side scripting languages like PHP and Perl to be more to my taste, and I have no aversion at all to writing SQL.

In the late 1990's when I was still using free web hosting, JavaScript probably was the best option for my then new online photo gallery. Whatever was the truth, it certainly was the way that I went. While learning Java or Flash might have been useful, I never managed to devote sufficient time to the task, so JavaScript turned out to be the way forward until I got a taste of server side scripting. Moving to paid hosting allowed for that to develop and the JavaScript option took a back seat.

Based on my experience of the browser wars and working with JavaScript throughout their existence, I was more than a little surprised at the buzz surrounding AJAX. Ploughing part of the way through WROX's Beginning AJAX did nothing to sell the technology to me; it came across as a very dry, jargon-blighted read. Nevertheless, I do see the advantages of web applications being as responsive as their desktop equivalents, but AJAX doesn't always guarantee this; as someone who has seen such applications crawling on IE6, I can certainly vouch for this. In fact, I suspect that may be behind the appearance of technologies such as AIR and Silverlight, so JavaScript may get usurped yet again, just like my move to a photo gallery powered on the server side.

Even with these concerns, using JavaScript to add a spot more interactivity is never a bad thing even if it can be overdone, hence the speed problems that I have witnessed. In fact, I have been known to use DOM scripting, but I need to have the use in mind before I can experiment with a technology; I cannot do it the other way around. Nevertheless, I am keen to see what JavaScript libraries such as jQuery and Prototype might have to offer (both have been used in WordPress). Since I have happened on their respective websites, they might make good places to start, and who knows where my curiosity might take me?

An inappropriate use of JavaScript

3^rd July 2007

I have seen a web application that displays thousands of records in a scrollable table (please bear with me, there is a decent reason for this). From the appearance of the table, it would be reasonable to assume that the table is generated by the server and output directly to the screen, but this isn't the case. What actually happens is that the server more or less outputs JavaScript code that is then executed. This takes the form of large arrays that are slotted into the DOM as the contents of the required table by a JavaScript function. With the large amounts of data involved, this means that the browser fully loads the client CPU while the JavaScript processing takes place, something that takes up to a minute to complete. Admittedly, the browser is IE6, but this was all on a PC with a 2.53 GHz Pentium 4 and 512 MB of memory. Getting the server to deliver standards-compliant (X)HTML for what is needed in the first place seems a much, much better approach to me.

Exploring AJAX

7^th June 2007

When I started it, my online photo gallery started out simply as a set of interlinked HTML pages. Over time, I discovered frames (yes, them!) and started to make use of JavaScript to make the slideshows slicker. In those days, I was working off free webspace provided by my ISP and client-side scripting was the only tool that I had for enhancing functionality. Having tired of the vagaries of client-side scripting while the browser wars were in full swing and incompatibilities reigned supreme, I went with paid hosting to get access to tools like Perl and PHP for server-side processing. Because their flexibility compared to JavaScript was a breath of fresh air to me, I am still a fan of the server-side approach.

The journey that I have just described is one that I now know was followed by many website builders around the same time. Nevertheless, I have still held on to JavaScript for some things, particularly for updating the DOM as part of making the pages more responsive to user interaction. In the last few years, a hybrid approach has been gaining currency: AJAX. This offers the ability to modify parts of a page without needing to reload the whole thing, generating a considerable amount of interest among web application developers.

The world of AJAX is evidently a complex one, though the underlying principle can be explained in simple terms. The essential idea is that you use JavaScript to call a server-side script, PHP is as good an example as any, that returns either text or XML that can be used to update part of a web page in situ without the need to reload it as per the traditional way of working. It has opened up so many possibilities from the interface design point of view that AJAX became a hot topic that still receives much attention today. One bugbear is efficiency because I have seen an AJAX application lock up a PC with a little help from IE6. There will always remain times when server-side processing is the best route, even if that needs to be balanced against the client-side approach.

Like its forbear DHTML, AJAX is really a development approach using a number of different technologies in combination. The DHTML elements such as (X)HTML, CSS, DOM and JavaScript are very much part of the AJAX world but server-side elements such as HTTP, PHP, MySQL and XML are also very much part of the fabric of the landscape. In fact, while AJAX can use plain text as the transfer format, XML is the one implied by the AJAX acronym and XSLT is used to transform XML into HTML. However, AJAX is not limited to the aforementioned technologies; for instance, I cannot see why Perl cannot play a role in place of PHP and ASP, both of which can be used for the same things.

Even in these standards-compliant days, browser support for AJAX remains diverse, to say the least, and it is akin to having MSIE in one corner and the rest in the other. Mind you, Microsoft did introduce the tools in the first place only for them to use ActiveX, while Mozilla created a new object type rather than continue this method of operation. Given that ActiveX is a Windows-only technology, I can see why Mozilla did what they did, and it is a sensible decision. In fact, IE7 appears to have picked up the Mozilla way of doing things.

Even with the apparent convergence, there will continue to be a need for the AJAX JavaScript libraries that are currently out there. Incidentally, Adobe has included one called Spry with Dreamweaver CS3. Nevertheless, I still like to find out how things work at the basic level and feel somewhat obstructed when I cannot do this. I remember perusing Wrox’s Professional AJAX and found the constant references to the associated function library rather grating; the writing style didn’t help either.

My taking a more granular approach has got me reading SAMS Teach Yourself AJAX in 10 Minutes as a means for getting my foot in the door. As with their Teach Yourself … in 24 Hours series, the title is a little misleading since there are 22 lessons of 10 minutes in duration (the 24 Hours moniker refers to there being 24 lessons, each of one hour in length). Anything composed of 10-minute lessons, even 22 of them, is never going to be comprehensive but, as a means for getting started, I have to say that the approach seems effective based on this volume. It has certainly whetted my appetite for giving AJAX a go, and it’ll be interesting to see how things progress from here.