I am always fascinated by the amount of Ajax tutorials and examples out there that totally ignore the backend part of an Ajax app. A lot of times you’ll find page-long ravings about the 6-7 lines of JavaScript that allow the client to make an HTTP request but when it comes to talking about the proxy script needed to allow for cross-domain requests a lot is glossed over as “you don’t need to know this, just use this script”.

That would not really be an issue if the scripts offered weren’t that bad. Unsanitized URLs are the main attacking point for cross-server-scripting attacks. If you use a PHP_SELF as the action of your forms you shouldn’t be too confused about a lot of mail traffic from your server or text links on your site you didn’t sign off and get money for.

The other thing about Ajax information on the web that amazes me is that people keep complaining about the slowness and problems with converting data from one format to another on the client side. Let us not kid ourselves: even after all the articles, books and podcasts about Ajax we still have no clue whatsoever what a visitor uses to look at our products. We cannot tell for sure what browser is used, if there is assistive technology involved or anything about the specs of the computer the browser runs on. This to me makes the client side the least preferable place to do heavy calculation and conversion.

The server side, on the other hand, is in your control and you know what it can do. Complex regular expressions, XSLT conversion, all of this is much easier to do on the backend – and you know that the text encoding will work to boot. A lot of complexity of Ajax apps is based on bad architecture and design decisions and on relying on the client side to provide necessary functionality.

So if you ask me what the ratio of client-to-server code of a good Ajax app is I’d say 30% client and 70% server. The 70% on the server should be used to provide security, non-JavaScript fallback functionality (yay accessibility) and conversion of data to small, easy-to-digest chunks for the client (think HTML and JSON). The 30% client side code should mainly be used up to enhance the usability of the product and make it easier for your visitors to reach their goals.

So here’s my plan for 2008: whenever I talk Ajax I will try to cover as much backend as frontend. I’ll do this by partnering with other experts as I myself created some terrible PHP in the past. I hope that others will follow that example as Ajax is a wonderful opportunity to bridge the gap between frontend and backend engineering – and we have to talk to each other to create a good app.

One of the most annoying things to me on the web is new tutorials that are full of assumptions, bad practices and generally outdated. The irony is that when you tell the authors about the issues their excuse in a lot of cases is that the pieces are mainly targeted at beginners.

How does that make sense? Surely when you want to cater something for beginners nowadays you’d want to make it work for them today, and not base it on old technology and practices.

Catered for the audience

Back when I still had a television there was one public service ad in Germany I really liked: it was a man talking in baby talk and acting terribly silly. He then bowed down below the camera, you heard a slapping sound and he re-emerged with sticky tape over his mouth. The announcer then said “we need programs for children, not childish programs”.

This is exactly what we need for beginners: tutorials that are up-to-date, easy to understand and are based on best practices and proven concepts. Not tutorials that cover easy to explain concepts that actually don’t apply any longer or have to be un-learnt as soon as you become professional developers.

Web competence?

The main reason is that it is hard enough for adults to learn things, but even harder to un-learn them. It is hard work to go through the four stages of competence and once you are at the last you don’t want to start again. However, in a fast paced environment as the web becoming unconsciously competent can also mean that you just don’t realize any longer that there are changes you should be covering.

Lowering the barrier

The main reason people write tutorials that promise a lot and don’t deliver is that they want to lower the barrier of entry for new developers. This is a nice enough idea as web development with all its loosely defined standards and unknowns can be quite daunting at first. However, this to me robs beginners of the chance to become great developers.

My personal idea of a good developer is showing the urge to understand and apply – showing the dedication, interest and stamina to learn about the environment you apply your work, not only the technicalities of it. This comes with experience but it also needs to be based on a good foundation.

Leaving them hungry for more

A good beginner’s tutorial should actually not give beginners solutions but make them understand concepts and point to information they can use to learn things for themselves. There is no greater way of learning than finding it out by yourself, on your own terms and in your own time. Anything else is just repetition.

The why of beginner’s tutorials

There are several reasons why people write beginner’s tutorials:

• They want to genuinely help other developers to come in and start learning the right way
• They want to avoid people being scared of learning the job
• They want a quick win – write about the easy stuff
• They want to show off their skills to lesser skilled developers
• They want to have a big audience – promising easy solutions makes for a lot of readers (think of tabloid journalism)

Not as easy as it seems

Now here is the tricky bit: writing a tutorial for beginners is actually a lot harder than writing about a more complex subject for a competent audience. The reasons are:

• you can cause much more damage with bad information – people trust you to be an expert and will believe and repeat what you said
• you will not get much constructive negative feedback – people will not dare to say you are wrong and the ones that could will not read what you wrote – as it is for beginners.
• it is easy to start with a preconception of what a beginner is – however beginners could be people that are just coming from another area of expertise they are very competent in.
• you don’t have a passion to work with – beginners are mostly scared or try to find a fast solution rather than true understanding

The last point is exactly what a lot of bad beginner’s tutorials work with and writing those will actually make it easy for you to get published. However, it will not make you a good trainer or writer, no matter how good the short term feedback and success is.

Danger signs

I know there will always be a lot of tutorials like this, as the number of hits / diggs and quick fame is important to people to make a name of themselves quickly, but I sincerely hope that this quick rant at least makes you reconsider doing another tutorial that starts with some of the classics like “XYZ in 10 minutes”, “quick solution for XYZ”, “ABC makes XYZ easy and fast!”, “You don’t need to understand XYZ when you do it the ABC way” or “XYZ in one line of code”.

Jetlagged like hell and confused I just arrived back from my holiday in Hong Kong, fired up my computer at home and realized that today it was my turn to say something on the advent calendar sites of the web:

• 24 ways – Keeping JavaScript dependencies at bay (English)
• Webkrauts – Große JavaScript Applikationen leicht gemacht (Deutsch)

The article describes a small and easy framework to create a modular JavaScript application that loads dependencies on demand and still gives you full control over what has already been loaded.

This is heavily inspired by the YUI config object and my talk at ajaxWorld East in March will deal with a similar topic.

Let me interrupt the stream of presentations here with a quick interlude telling you about how cool Hong Kong is. I am currently sitting here at a cafe writing this on my newest toy – an Asus eeepc which I bought for about 200 GBP the day before yesterday.

I like Hong Kong to bits, there is hardly any city that is as efficient and easily accessible. People are very proficient in English and all signs are bilingual. On the other hand you can get Bladerunner moments when you leave the neon corners and end up in a local side street with interesting food and products you have no clue about.

It is easy and cheap to get a cab should you get lost but in general there is hardly ever any need to. The underground (MTR) is easy to find with signs pointing to the nearest stations all over the shop and inside it you can see on the trains which station you came from, which direction you go and which other lines connect on an illuminated map.

The easiest way to pay for the tube is an octopus card, which is a prepaid card you get for about 10 GBP with 3 pound being a deposit you can redeem on your last day should you want to return the card. This card also enables you to buy things in shops, which can come in handy should you not want to collect a lot of change :-).

Connectivity is nuts, you’ll find free wireless in nearly every cafe or shopping centre (and boy are there a lot around here) and if you want to be 100% sure you can sign up for a 30 day access with PCCW, a massive provider who has hotspots in nearly every corner of the city.

Mobile coverage is even on the underground which means you hear people happily chatting away covering their mouth and half the mobile with their hands.

There are cashpoints on nearly every train station with no fees but the UK bank ones (cheers, Barclays) and you can pay with Visa almost everywhere without getting any strange looks.

You are also never far from clean and freely available public convenience places should you need to wash your hands or comparable tasks.

All in all it is a joy being here and with the flight and hotel being very affordable I can recommend anyone coming here, should you want to stock up on things that need batteries :-)

Yesterday the first ever PlugLondon event took place in the Skype offices off Tottenham Court Road in London, England. PlugLondon was the idea of Jonathan Gabbai of Ebay, Paul Amery and Antoine Bertout of Skype and me and we wanted to give London based developers a chance to show off what they have done and network in an environment devoid of HR, PR or other business lures or pressures.

The signs were bad: it was raining cats and dogs (the classic London rain that will get you from all sides and therefore is not stopable with a brolly), the tubes were overcrowded as there were also protest marches planned in the city and generally the westend was packed with shoppers trying to get their christmas presents.

Nevertheless about 40-50 people showed up and we consumed the pizza and drinks provided before heading off to the Bricklayer’s Arms for some more drinks.

So far all I heard was good feedback and some very good suggestions how to move the event forward. We’ll see what we can do for the next one, but I guess we’ll wait a while till the weather is better and people came back from holidays. I personally am off to a 8 day trip to Hongkong on Tuesday.

• Check the PlugLondon photos
• See other blogposts about pluglondon on technorati