135. Libraries

Paul Boag

In this week’s show we talk with John Resig on javaScript libraries and address the question what is more important when we release an app: speed or quality?

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News and events

The complexity tax

Don’t you hate it when somebody beats you to the punch? I recently finished writing a report for our biggest client (Wiltshire Farm Foods). It talks a lot about the need to simplify and remove complexity. It is a lesson we should all learn and so I am in the process of turning extracts from the report into a blog post which we will cover in next weeks show.

However, it would appear I have been too slow and that Gerry McGovern has beaten me to it with an excellent post on the cost of complexity. However, where I focus on why simplicity is important, he addresses the underlying causes of complexity.

For me his post is summed up in the following quote…

Most organizations are producing far too much content. Too many emails, too many PowerPoints, too many reports, too many webpages. All this content creation activity keeps a lot of people busy.

If you are part of a large organisation or work on a substantial website you need to read this post.

10 Rules for Driving Traffic Using Forums

What do you do if you have no marketing budget but have some free time to promote your site? Well, there are a number of guerilla marketing techniques you could use but contributing to forums is one of the most effective.

Sitepoint has posted an article explaining why forums are a great way of driving traffic to your site. It goes on to suggest 10 rules for doing so effectively. These include…

  • Build your profile
  • Follow the rules
  • Start by responding
  • Contribute your expertise
  • Don’t be a ‘me too’ poster
  • Don’t self promote
  • Explain yourself, but be brief
  • If you’re wrong, say so
  • Write intelligently and correctly
  • Negativity is a no-no

This is an excellent article and one that you should definitely read before using forums as a marketing tool. If you do not, you are in danger of damaging your brand, rather than driving traffic.

Accessibility in suit and tie

The life of the corporate web worker who cares about standards and accessibility can be a frustrating one; hampered by office politics and archaic content management systems. In an article on the Think Vitamin site, Bruce Lawson looks at what you can do to make sure your projects are as accessible for your users as possible.

Its a very pragmatic article, which I love. Bruce works from the premise that this is going to be tough and makes suggestions like "some accessibility is better than none". He also talks about the need for ‘buy-in from the top’ but goes on to provide practical tips about how to get that buy in. What is more, his arguments for accessibility were backed up with facts. For example…

Finally, he looks at how to get content providers onboard through education and getting them writing HTML rather than relying on the WYSIWYG editor.

UK Government Browser Guidelines

Our final story raises an interesting discussion; should you decide which browsers to support based on popularity or capability?

Apparently, the UK government believes we should test on the basis of popularity. In a draft document advising public sector websites, it suggests that if a browser appears in visitor logs as being below an arbitrary percentage of total “unique visitors”, then it should not be listed as being “fully supported”.

On the surface this appears very sensible. However, as Jon Hicks points out on his site, this can create problems. He writes…

It isn’t clear how the supported browser list would be enforced, but I’m concerned that this approach will encourage browser sniffing, a move that will exclude browsers like Omniweb, Shiira and iCab, simply because their name isn’t ‘Safari’. They share the exact same rendering engine, and therefore require no further testing. You can be more inclusive without spending any extra resources.

In other words we should be defining our list of supported browsers based on capability rather than popularity. This is the approach used by Yahoo! and it is one that I would fully support.

The Yahoo model supports all browsers through progressive enhancement and graceful degradation, without the need to test on every browser. Its a neat solution but one that the UK government guidelines specifically say they do not advocate…

These guidelines do not advocate specific development methodologies, for example graceful degradation or progressive enhancement. However, it is widely accepted that sites conforming to open web standards such as XHTML and CSS are more likely to work well across a wide range of browsers.

How come if they are widely accepted, do they not advocate them?

Fortunately there is an opportunity to change things before this is set in stone. I recommend reading the WaSP article on the recommendations and then sending some polite feedback to the powers that be.

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Interview: John Resig on javaScript Libraries

Paul:Joining me today is John Resig, who is famous for jQuery and the work that he has been doing with jQuery. John, it is great to have you on the show.

John:Well, thanks for having me.

Paul:I have to say this at the beginning. I have to get this out of the way. I absolutely love working with jQuery, and it’s an absolute pleasure. I remember twittering just a few days ago that every time I start doing anything in jQuery it makes me smile, so that’s got to be a good sign.

John:Well that’s good. I’m glad to hear it.

Paul: What I wanted to do today is get you on the show and not just for me to suck up and say how great jQuery is, but to kind of look a little bit broader at the subject of JavaScript libraries. Because I have to say from a personal point of view my opinion has changed quite a lot about JavaScript libraries and I’m kind of interested in your perspective on things as somebody that’s actually created one. I think the place I want to start is for a long time I had the attitude that you shouldn’t use JavaScript or indeed any library and that you should know the underlying code yourself and all of this kind of thing. Let’s start with the question of how do you know if it’s appropriate to use a JavaScript library? When is it appropriate to use it? What’s your opinion on that?

John:Well, I guess my opinion is it’s always appropriate, and I mean the simple fact of the matter is that there’s two things. One is that when you’re developing, you’re trying to support, generally a large number of browsers simultaneously. This is the same as if you are doing CSS development, JavaScript development, you want to support a large enough market share and you want to make that development process easy. The problem is twofold that you’re going to be encountering weird browser bugs and the APIs, the different utilities the browsers provide, will be different. For example, Internet Explorer provides different ways of handling events from all the other browsers. So what libraries do is that they remove you away from dealing with browser bugs, which is huge. And at the same time they provide a simple interface that you can interact with that will just work ubiquitously.

Paul:Is there a problem there in the sense of, you know, somebody came along and they basically learned to write jQuery for example from scratch, but never learned the kind of underlying JavaScript? Is there a problem there, do people need to know JavaScript before they start using a library?

John:It depends on the library, but I don’t think you do. I don’t think you have to know JavaScript. In a lot of ways, at least in my experience with jQuery directly there’s a lot of people who have used jQuery who have never done any programming whatsoever. jQuery does embody a lot of advanced concepts but you don’t necessarily have to know them in order to make good use of jQuery. I know this sort of translates well into some of the other libraries but one point of concern you brought up was what if someone learns a library but doesn’t learn JavaScript? I used to be more concerned about that, if someone only knew a library and I guess from a purist perspective, that’s a bad thing. Fundamentally, you want people to be getting better at programming JavaScript, not this specific thing. However, I think the reality of it is, is that so many people are just using JavaScript or CSS or doing web design, they just want to get their job done. It’s not really a matter for them of becoming an excellent JavaScript programmer or awesome CSS user, you want to get from A to Z and finish their work in an effective manner that works everywhere. So I think it’s important to realize that this market, so to speak, exists. It’s a very large one. And that ignoring it completely will just leave users frustrated and going back to the simple cut and copy paste scripts that they used to use. So, I think what libraries are doing is they are instilling good standards, they are instilling good practices, even though the users don’t necessarily know about it. And then eventually what’s good is that since these libraries have these good practices that users can always open up a library and read about it and try to understand better what’s going on.

Paul:I guess that’s always been a little bit of my concern with relying heavily on a library is that if you come across something that’s a problem or a bug or something like that, you can’t fix it yourself because you don’t necessarily know your way around the library. What’s your response to people that say stuff like that?

John:Well by the same token if you encounter a problem with a browser you are far less capable of fixing that issue. There’s really no way about it other than that ultimately it would be good to have that knowledge, absolutely. I fully support people who want to do that and I’m writing a second book now encouraging people to do that, to dig into libraries, to learn more, to build their own. What’s important here is that you just don’t, you can’t force people to do it if they, one if they don’t want to or if they’re just not capable. There’s no reason I feel to force a designer, someone who’s a designer by trade to learn the fundamentals of object oriented programming, or functional programming. Theoretically that can help them some way in the future but what’s more important to them is doing good design and I think by helping people keep their focus where it should be. Obviously if a library is able to help programmers program better, that’s good as well. It’s all about helping people keeping their focus and making sure they aren’t down a rabbit hole getting sidetracked.

Paul:I think that’s the thing that really attracted me to jQuery is as a front-end interface designer was the fact that I could pick it up and run with it very easily. The conclusion I came to is, “OK. Well if I do by some chance find a major problem with it, there’s a massive community of very clever people out there that I can ask and I can get help from.” So, that kind of reassured me, I think. If then, we’ve kind of come to terms with the fact: “OK we want to use a library.” There are so many different ones out there. Run us through some of the different options available and the pros and cons and how do you go about picking which library is right for you?

John:Well it really depends a lot. There’s a coupe questions you need to answer. Probably the most important of which is you need to ask yourself, how do you want to write JavaScript? Because libraries end up augmenting or really changing the style of how you write JavaScript. So, finding a library that you like how it looks. It sounds very superficial, but you like how it looks, you like how the code feels is a great place to start. There’s obviously a lot of libraries to choose from. There’s a select group of libraries whose quality is generally above the others and the popularity of those libraries generally reflects the quality as well. Out of those I pick generally jQuery, Prototype, Yahoo UI, dojo, then also MooTools and sometimes XJS. What’s interesting is all those libraries are open source and they are all the most popular JavaScript libraries. I don’t think that’s a coincidence. It’s just a matter of fact that in the web these open source frameworks are going to improve better and attract more users and generally have better community to surround them. So out of these libraries though you break down into a lot of different paradigms for development. I’ll try to summarize as best I can, but it really is not substitute for trying it out yourself. Looking and seeing some examples you can have a pretty good feel right away. So, Prototype and MooTools, they both extend the native objects of the language. They both try to improve the JavaScript language itself. So they add new methods to arrays, they make strings better, at the same time they provide things like object-oriented code
, and all the way out to doing things like events and AJAX. The normal things that you would expect. But at a very broad level they are trying to improve the overall quality of the language and of the experience. Then you have Dojo, Yahoo UI, and XJS and they are generally very modular, very package oriented and they have components you can easily snap in and out with nice ways of handling dependencies and it can end up being a very cleanly architected style of coding. They really support object-oriented code, and additionally events, AJAX, all the normal stuff you would expect. I would tend to group jQuery a little bit differently in that jQuery is more oriented toward improving the relationship between JavaScript and HTML and that it’s highly focused on searching through an HTML document, modifying some things, just getting in and getting out. Unobtrusive, and it doesn’t provide any language features, it doesn’t provide any object-oriented code writing features, it’s just hyper-focused at the task on hand.

Paul:It strikes me from my experience with jQuery that it’s very much a tool that’s primarily focused at helping front-end interface people implement the kind of functionality that they require from a usability point of view rather than necessarily doing, I mean would you build massive applications in something like jQuery?

John:It’s absolutely possible and people do it all the time. For example, T-Mobile’s T-Online in Germany, they built their entire user area so like their mail, their calendar, and everything using jQuery. So it’s absolutely used for very large projects. What I think is very interesting for jQuery at least is that while we don’t explicitly provide the object-oriented styles that most hardcore developers are used to we provide some very interesting alternatives especially they way it, like functional programming that I think actually end up suiting development very well. It’s very different, I will completely grant that, but it’s still very capable of scaling quite large.

Paul:So if people go out there and they have a kind of play around with these different libraries and try each of them out as you say to kind of find what fits their style of coding, once they’ve found something that kind of codes in the way they would like to, for example for me the similarities between jQuery and CSS made it a very natural fit, but what are the kind of things that you should look for from a functional perspective? What kind of things should be included in a JavaScript library? Does that make sense?

John:At the very core there should be a set of features. Of the libraries that I listed previously they all have methods for doing DOM traversal, so traversing through an HTML document, modifying an HTML document, events, so handling user interaction, animations and AJAX. All of them have some support for that to one degree or another. You can be fairly safe in knowing that if you pick a library you will have that base level. In my opinion those sets of features are probably the most important features and the ones that you end up using the most with your applications. Some people might say in their particular case that maybe animations aren’t as important, or maybe that they aren’t using AJAX, it really depends but for most of the time that set of features is fairly comprehensive. On top of that you really have to start to, once you’ve tried to use it, and once you’ve played around, there’s a whole set of secondary features that you kind of have to dig into, ones that aren’t immediately code-related. Things like the community around a library, the documentation for a library and even the health of the projects themselves.

Paul:What do you mean by that last one, the health of a project?

John:There’s a lot of things. In health, do they have an active development team? Are there developers? Are there multiple developers? It’s the famous hit by a bus; if a developer is hit by a bus will the project still continue? Is there a team will continue? Can you view the source code? Is there a repository where you can go? Is there a bug tracker where you can submit bugs? And finally is there a test suite, is what you’re going to be using going to be tested and analyzed to make sure it stays working. Another point that’s important to bring up is that a lot of browsers now are starting to integrate the test suites of these libraries into their test suite. So for example actually this is a lot of my work at Mozilla, was integrating the test suites of Prototype, Scriptaculous, jQuery, MochiKit, a bunch of libraries into our test suite such that if we ever added a change that caused a regression to happen in a library we would catch it and we would fix it on our end. Obviously we would do this in a very smart way, we wouldn’t just blindly be like, “Oh something broke!” We would communicate to the library what the issue was or whatever and this has been very big because now you can, there’s an extra level of safety and security here, in that you’ll know that if you’re using a library like this that it’s going to continue to work going forward in these browsers. That’s an extra level of safety that your personal code can’t provide. I think that’s very interesting. I want to jump back here really quick to the other issues I mentioned.

Paul:Sorry, I distracted you there and we took you off topic.

John:It’s OK, it’s OK, of community and documentation. So community, it can be usually be pretty easy to determine the health of the community. All these libraries will have some sort of a mailing list or a forum that you can go to. Just hopping on there, seeing how many messages are posted, seeing what the typical response is like, how they treat new users, just stuff like that it can be really useful because if you’re just starting out, you know you’re going to have some pretty basic questions. Do they understand your problems? Do they help you out? Doing some searches on Google for example to see how many people are talking about it, or using a service like Technorati or something. Are people blogging about it? Is it positive? Are they having problems? The other thing is documentation. This is also pretty easy to tell. If you are starting out with a library, you’re probably going to start out by doing a quick test, running a simple application just to get a feel for it. When you’re doing that you’re immediately going to be in the documentation trying to figure out how things work. I think you’ll be able to determine pretty quickly if the documentation quality meets a standard that you, because if you aren’t, if the documentation just isn’t that good, you’ll immediately have problems and I guess you will have to resort to the mailing list or the forums or whatever. Secondary is, do they have good examples? Do they have books if you want to learn from a book? Do they have books that you can buy to learn from? So again there’s a whole lot of issues here but what a lot of it boils down to is looking at the libraries, looking at their style of code, does it seem alright with you? Then just doing a quick test with each of the libraries that you’ve picked out, building like a menu or just a basic form of interaction. How easy is it? How hard is it? Does it in fact mesh with you well? This is something you can do over the course of a single day and it definitely shouldn’t take you any longer th

an that. If it’s taking longer than that then you probably want to try a different library. Ultimately you should be trying to use these libraries to make your development simpler and easier. If it doesn’t improve your productivity, if it doesn’t improve the quality of your code then you probably shouldn’t be using it to begin with.

Paul:Tell us a little bit about the kind of plug-in architectures that exists around many JavaScript libraries. Certainly I know there’s a strong plug-in architecture with jQuery. Does the same kind of thing exist with other libraries?

John:It depends. What jQuery has is a little bit unique in that we provide a number of plug-in points that plug-ins can snap into and extend how jQuery works. So they can add in new CSS selector behavior, or they can add in new events or all sorts of intricate additions. Other libraries have things that aren’t quite of the same vane, in that they’ll have modules or packages that you can use. Also another thing that varies is how do the various projects treat these plug-ins? At least with jQuery there’s a dedicated plug-in repository that’s used that plug-ins are listed in that you can browse through, you can see ratings, comments, discussions and things like that. Currently no other framework has something similar to that to the best of my knowledge. It’s much looser, just people uploading, putting things to their websites or Google code or some such. So again, at least to me, what makes plug-ins, jQuery-style plug-ins important is that they are, that there’s extension points and that they are supported by jQuery fully.

Paul: The only thing that I think that I kind of struggle with a little bit about plug-ins, you know I love the idea that there are other people out there that can do the hard work for me in that they can develop something I was looking for, and I love the fact that I can go to jQuery, I can type in whatever I’m looking for and it will pull back stuff. I’m always a bit unsure mind about how reliable those plug-ins are, you know as you’ve been saying with the kind of, the core jQuery library that you’ve created I know there’s a big team of developers working on it, I know that it’s thoroughly tested, I know what browsers it’s tested against, all of that kind of stuff. Plug-ins are a bit more of an unknown entity. Is there any kind of advice that you can provide about judging whether a plug-in or module or whatever is reliable or not?

John:I mean you sort of have to use the same standards that you would use in looking at a library. Looking at, what you mentioned, is it tested? Is there good documentation? Are there, how many developers are working on it? Like for example in the jQuery project we started a sort of, sub-project called jQuery Glide in which we’ve taken a whole bunch of plug-ins and actually blessed them and proved them, given them themes, excellent documentation, examples, all this stuff and made them sort of official. We’re doing this more and more, trying to bring in more plug-ins, improve their quality and make sure that they’re up to our standards. There’s still tons and tons of plug-ins that are just excellent, but the issue comes down to that you have to sort of train your eye to look at, and be able to spot when something has good quality. The thing that’s easiest for a plug-in author or a library author to do is to just set up a page that has their code on it and has a basic example. At the very least every single library is going to have that. If you dig in and see that it has documentation, that it has tests, you begin to realize that that plug-in is a much higher quality, at the very least. I think it’s really starting to dig in to these side issues, that you begin to get a better picture of how, of the true nature and of the true health of a particular library.

Paul:Excellent! That’s really useful and I think it’s easy to just look at these libraries and indeed the plug-ins as well and ask, “Well do they have the basic functionality that I require?” But, like you say, looking at things like the community and documentation and things like that are equally important. It’s been very useful John. Thank you for taking the time to come on the show. No doubt we will get you back in the future to talk about some of the specific things going on with jQuery and maybe this book that you’re writing as well, sounds very good. Thanks for your time.

John:Thanks for having me, Thank you.

Thanks to Todd Dietrich for transcribing this interview.

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Listeners feedback:

Quality or Quickly?

What is more important, to reach market quickly or to launch with a quality product?

I received this question from Pete in South Africa…

I have been working on a small web application, which I hope to launch soon. My problem is that I am spending ages tweaking and improving it before launch. I fear that if I spend much longer on it somebody will beat me to market. What is more important, getting the product right or launching it quickly?

It is a good question and one with no single answer. It is certainly something we have been struggling with as we prepare to launch GetSignOff.

To read the rest of this blog click here.

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