Tags: extensible

The Extensible Web Summit is taking place in Berlin today because Web Components are that important. I wish I could be there, but I’ll make do with the live notes, the IRC channel, and the octothorpe tag.

I have conflicting feelings about Web Components. I am simultaneously very excited and very nervous. That’s probably a good sign.

Here’s what I wrote after the last TAG meetup in London:

This really is a radically new and different way of adding features to browsers. In theory, it shifts the balance of power much more to developers (who currently have to hack together everything using JavaScript). If it works, it will be A Good Thing and result in expanding HTML’s vocabulary with genuinely useful features. I fear there may be a rocky transition to this new way of thinking, and I worry about backwards compatibility, but I can’t help but admire the audacity of the plan.

And here’s what I wrote after the Edge conference:

If Web Components work out, and we get a kind emergent semantics of UI widgets, it’ll be a huge leap forward for the web. But if we end up with a Tower of Babel, things could get very messy indeed. We’ll probably get both at once.

To explain…

The exciting thing about Web Components is that they give developers as much power as browser makers.

The frightening thing about Web Components is that they give developers as much power as browser makers.

When browser makers—and other contributors to web standards—team up to hammer out new features in HTML, they have design principles to guide them …at least in theory. First and foremost—because this is the web, not some fly-by-night “platform”—is the issue of compatability:

Support existing content

Degrade gracefully

You can see those principles at work with newly-minted elements like canvas, audio, video where fallback content can be placed between the opening and closing tags so that older user agents aren’t left high and dry (which, in turn, encourages developers to start using these features long before they’re universally supported).

You can see those principles at work in the design of datalist.

You can see those principles at work in the design of new form features which make use of the fact that browsers treat unknown input types as type="text" (again, encouraging developers to start using the new input long before they’re supported in every browser).

When developers are creating new Web Components, they could apply that same amount of thought and care; Chris Scott has demonstrated just such a pattern. Switching to Web Components does not mean abandoning progressive enhancement. If anything they provide the opportunity to create whole new levels of experience.

Web developers could ensure that their Web Components degrade gracefully in older browsers that don’t support Web Components (and no, “just polyfill it” is not a sustainable solution) or, for that matter, situations where JavaScript—for whatever reason—is not available.

Web developers could ensure that their Web Components are accessible, using appropriate ARIA properties.

But I fear that Sturgeon’s Law is going to dominate Web Components. The comparison that’s often cited for Web Components is the creation of jQuery plug-ins. And let’s face it, 90% of jQuery plug-ins are crap.

This wouldn’t matter so much if developers were only shooting themselves in the foot, but because of the wonderful spirit of sharing on the web, we might well end up shooting others in the foot too:

1. I make something (to solve a problem).
2. I’m excited about it.
3. I share it.
4. Others copy and paste what I’ve made.

Most of the time, that’s absolutely fantastic. But if the copying and pasting happens without critical appraisal, a lot of questionable decisions can get propagated very quickly.

To give you an example…

When Apple introduced the iPhone, it provided a mechanism to specify that a web page shouldn’t be displayed in a zoomed-out view. That mechanism, which Apple pulled out of their ass without going through any kind of standardisation process, was to use the meta element with a name of “viewport”:

<meta name="viewport" value="...">

The value attribute of a meta element takes a comma-separated list of values (think of name="keywords": you provide a comma-separated list of keywords). But in an early tutorial about the viewport value, code was provided which showed values separated with semicolons (like CSS declarations). People copied and pasted that code (which actually did work in Mobile Safari) and so every browser must support that usage:

Many other mobile browsers now support this tag, although it is not part of any web standard. Apple’s documentation does a good job explaining how web developers can use this tag, but we had to do some detective work to figure out exactly how to implement it in Fennec. For example, Safari’s documentation says the content is a “comma-delimited list,” but existing browsers and web pages use any mix of commas, semicolons, and spaces as separators.

Anyway, that’s just one illustration of how code gets shared, copied and pasted. It’s especially crucial during the introduction of a new technology to try to make sure that the code getting passed around is of a high quality.

I feel kind of bad saying this because the introductory phase of any new technology should be a time to say “Hey, go crazy! Try stuff out! See what works and what doesn’t!” but because Web Components are so powerful I think that mindset could end up doing a lot of damage.

Web developers have been given powerful features in the past. Vendor prefixes in CSS were a powerful feature that allowed browsers to push the boundaries of CSS without creating a Tower of Babel of propietary properties. But because developers just copied and pasted code, browser makers are now having to support prefixes that were originally scoped to different rendering engines. That’s not the fault of the browser makers. That’s the fault of web developers.

With Web Components, we are being given a lot of rope. We can either hang ourselves with it, or we can make awesome …rope …structures …out of rope this analogy really isn’t working.

I’m not suggesting we have some kind of central authority that gets to sit in judgement on which Web Components pass muster (although Addy’s FIRST principles are a great starting point). Instead I think a web of trust will emerge.

If I see a Web Component published by somebody at Paciello Group, I can be pretty sure that it will be accessible. Likewise, if Christian publishes a Web Component, it’s a good bet that it will use progressive enhancement. And if any of the superhumans at Filament Group share a Web Component, it’s bound to be accessible, performant, and well thought-out.

Because—as is so often the case on the web—it’s not really about technologies at all. It’s about people.

And it’s precisely because it’s about people that I’m so excited about Web Components …and simultaneously so nervous about Web Components.

Bruce Lawson’s personal site  : Notes on accessibility of Web Components

Bruce’s thoughts on ensuring accessibility in Web Components. He thinks that the vocabulary of ARIA is up to the job, so that’s good enough for me.

Section for peer-reviewed Custom Elements · Issue

Some sensible thoughts from Addy on how Web Components might be peer-reviewed.

Aerotwist - Web Components and the Three Unsexy Pillars

A healthy dose of scepticism about Web Components, looking at them through the lenses of accessibility, security, and performance.

I share some of this concern: Web Components might look like handy ready-made out-of-the-box solutions, but the truth is that web developers have to do much more of the hard graft that was traditionally left to the browser.

I went up to London for the Edge Conference on Friday. It’s not your typical conference. Instead of talks, there are panels, but not the crap kind, where nobody says anything of interest: these panels are ruthlessly curated and prepared. There’s lots of audience interaction too, but again, not the crap kind, where one or two people dominate the discussion with their own pet topics: questions are submitted ahead of time, and then you are called upon to ask it at the right moment. It’s like Question Time for the web.

Components

The first panel was on that hottest of topics: Web Components. Peter Gasston kicked it off with a superb introduction to the subject. Have a read of his equally-excellent article in Smashing Magazine to get the gist.

Needless to say, this panel covered similar ground to the TAG meetup I attended a little while back, and left me with similar feelings: I’m equal parts excited and nervous; optimistic and worried. If Web Components work out, and we get a kind emergent semantics of UI widgets, it’ll be a huge leap forward for the web. But if we end up with a Tower of Babel, things could get very messy indeed. We’ll probably get both at once. And I think that’ll be (mostly) okay.

I butted into the discussion when the topic of accessibility came up. I was a little worried about what I was hearing, which was mainly, “Oh, ARIA takes care of the accesibility.” I felt like Web Components were passing the buck to ARIA, which would be fine if it weren’t for the fact that ARIA can’t cover all the possible use-cases of Web Components.

I chatted about this with Derek and Nicole during the break, but I’m not sure if I was articulating my thoughts very well, so I’ll have another stab at it here:

Let me set the scene for Web Components…

Historically, HTML has had a limited vocubalary for expressing interface widgets—mostly a bunch of specialised form fields like, say, the select element. The plus side is that there’s a consensus of understanding among the browsers, so you don’t have to explain what a select element does; the browsers already know. The downside is that whenever we want to add a new interface element like input type="range", it takes time to get into browsers and through the standards process. Web Components allow you to conjure up interface elements, and you don’t have to lobby browser makers or standards groups in order to make browsers understand your newly-minted element: you provide all the behavioural and styling instructions in one bundle.

So Web Components make use of HTML, JavaScript, and (scoped) CSS. The possibility space for the HTML is infinite: if you need an element that doesn’t exist, you just invent it. The possibility space for the JavaScript is pretty close to infinite: it’s a Turing-complete language that can be wrangled to do just about anything. The possibility space for CSS isn’t infinite, but it’s pretty darn big: there’s not much you can’t do with it at this point.

What’s missing from that bundle of HTML, JavaScript, and CSS are hooks for assistive technology. Up until now, this is something we’ve mostly left to the browser. We don’t have to include any hooks for assistive technology when we use a select element because the browser knows what it is and can expose that knowledge to the assistive technology. If we’re going to start making up our own interface elements, we now have to take on the responsibility of providing that information to assistive technology.

How do we that? Well, right now, our only option is to use ARIA …but the possibility space defined by ARIA is much, much smaller than HTML, JavaScript, or CSS.

That’s not a criticism of ARIA: that’s the way it was designed. It’s a reactionary technology, designed to plug the gaps where the native semantics of HTML just don’t cut it. The vocabulary of ARIA was created by looking at the kinds of interface elements people are making—tabs, sliders, and so on. That’s fine, but it can’t scale to keep pace with Web Components.

The problem that Web Components solve—the fact that it currently takes too long to get a new interface element into browsers—doesn’t have a corresponding solution when it comes to accessibility hooks. Just adding more and more predefined ARIA roles won’t cut it—we need some kind of extensible accessibility that matches the expressive power of Web Components. We don’t need a bigger vocabulary in ARIA, we need a way to define our own vocabulary—an extensible ARIA, if you will.

Hmmm… I’m still not sure I’m explaining myself very well.

Anyway, I just want to make sure that accessibility doesn’t get left behind (again!) in our rush to create a new solution to our current problems. With Web Components still in their infancy, this feels like the right time to raise these concerns.

That highlights another issue, one that Nicole picked up on. It’s really important that the extensible web community and the accessibility community talk to each other.

Frankly, the accessibility community can be its own worst enemy sometimes. So don’t get me wrong: I’m not bringing up my concerns about the accessibility of Web Components in order to cry “fail!”—I just want to make sure that it’s on the table (and I’m glad that Alex is one of the people driving Web Components—his history with Dojo reassures me that we can push the boundaries of interface widgets on the web without leaving accessibility behind).

Anyway …that’s enough about that. I haven’t mentioned all the other great discussions that took place at Edge Conference.

Developer Tooling

The Web Components panel was followed by a panel on developer tools. This was dominated by representatives from different browsers, each touting their own set of in-browser tools. But the person who I really wanted to rally behind was Kenneth Auchenberg. He quite rightly asks why our developer tools and our text editors are two different apps. And rather than try to put text editors into developer tools, what we really want is to pull developer tools into our text editors …all the developer tools from all the browsers, not just one set of developer tools from one specific browser.

If you haven’t seen Kenneth’s presentation from Full Frontal, I urge you to watch it or listen to it.

I had my hand up to jump into the discussion towards the end, but time ran out so I didn’t get a chance. Paul came over afterwards and asked what I was going to say. Here’s what I told him…

I’m fascinated by the social dynamics around how browsers get made. This is an area where different companies are simultaneously collaborating and competing.

Broadly speaking, the feature set of a web browser can be divided into two buckets:

In one bucket, you’ve got the support for standards like HTML, CSS, JavaScript. Now, individual browsers might compete on how quickly or how thoroughly they get those standards implemented, but at this point, there’s no disagreement about the fact that proprietary crap is bad, standards are good, and that no matter how painful the process can be, browser makers all need to get together and work on standards together. Heck, even Apple can’t avoid collaborating on this stuff.

In the other bucket, you’ve got all the stuff that browsers compete against each other with: speed, security, the user interface, etc. A lot of this takes place behind closed doors, and that’s fine. There’s no real need for browser makers to collaborate on this stuff, and it could even hurt their competetive advantage if they did collaborate.

But here’s the problem; developer tools seem to be coming out of that second bucket instead of the first. There doesn’t seem to be much communication between the browser makers on developer tools. That’s fine if you see developer tools as an opportunity for competition, but it’s lousy if you see developer tools as an opportunity for interoperability.

This is why Kenneth’s work is so important. He’s crying out for more interoperability between browsers when it comes to developer tools. Why can’t they all use the same low-level APIs under the hood? Then they can still compete on how pretty their dev tools look, without making life miserable for developers who want to move quickly between browsers.

As painful as it might be, I think that browser makers should get together in some semi-formalised way to standardise this stuff. I don’t think that the W3C or the WHATWG are necessarily the right places for this kind of standardisation, but any kind of official cooperation would be good.

Build Process

The panel on build processes for front-end development kicked off with Gareth saying a few words. Some of those words included the sentence:

Make is probably older than you.

Cue glares from me and Scott.

Gareth also said that making websites means making software. We’re all making software—live with it.

This made me nervous. I’ve always felt that one of the great strengths of the web has been its low barrier to entry. The idea of a web that can only be made by qualified software developers doesn’t sound like a good thing to me.

Fortunately, things got cleared up later on. Somebody else asked a question about whether the barrier to entry was being raised by the complexity of tools like preprocessors, compilers, and transpilers. The consensus of the panel was that these are power tools for power users. So if someone were learning to make a website from scratch, you wouldn’t start them off with, say, Sass, without first learning CSS.

It was a fun panel, made particulary enjoyable by the presence of Kyle Simpson. I like the cut of his jib. Alas, I didn’t get the chance to tell him that in person. I had to duck out of the afternoon’s panels to get back to Brighton due to unforeseen family circumstances. But I did manage to catch some of the later panels on the live stream.

Closing thoughts

A common thread I noticed amongst many of the panels was a strong bias for decantralisation, rather than collaboration. That was most evident with Web Components—the whole point is that you can make up your own particular solution rather than waiting for a standards body. But it was also evident in the Developer Tools line-up, where each browser maker is reinventing the same wheels. And when it came to Build Process, it struck me that everyone is scratching their own itch instead of getting together to work on an itch solution.

There’s nothing wrong with that kind of Darwinian approach to solving our problems, but it does seem a bit wasteful. Mairead Buchan was at Edge Conference too and she noticed the same trend. Sounds like she’s going to do something about it too.

I was up in London yesterday to spend the day with the web developers of a Clearleft client, talking front-end architecture and strategies for implementing responsive design. ‘Twas a good day, although London always tires me out quite a bit.

On this occasion, I didn’t head straight back to Brighton. Instead I braved the subterranean challenges of the Tube to make my way across london to Google Campus, where a panel discussion was taking place. This was Meet The TAG.

TAG is the Technical Architecture Group at the W3C. It doesn’t work on any one particular spec. Instead, it’s a sort of meta-group to steer how standards get specified.

Gathered onstage yesterday evening were TAG members Anne van Kesteren, Tim Berners-Lee, Alex Russell, Yehuda Katz, and Daniel Appelquist (Henry Thompson and Sergey Konstantinov were also there, in the audience). Once we had all grabbed a (free!) beer and settled into our seats, Bruce kicked things off with an excellent question: in the intros, multiple TAG members mentioned their work as guiding emerging standards to make sure they matched the principles of the TAG …but what are those principles?

It seemed like a fairly straightforward question, but it prompted the first rabbit hole of the evening as Alex and Yehuda focussed in on the principle of “layering”—stacking technologies in a sensible way that provides the most power to web developers. It’s an important principle for sure, but it didn’t really answer Bruce’s question. I was tempted to raise my hand and reformulate Bruce’s question into three parts:

1. Does the Technical Architecture Group have design principles?
2. If so, what are there?
3. And are they written down somewhere?

There’s a charter and that contains a mission statement, but that’s not the same as documenting design principles. There is an extensible web manifesto—that does document design principles—which contains the signatures of many (but not all) TAG members …so does that represent the views of the TAG? I’d like to get some clarification on that.

The extensible web manifesto does a good job of explaining the thinking behind projects like web components. It’s all about approaching the design of new browser APIs in a sensible (and extensible) way.

I mentioned that the TAG were a kind of meta-standards body, and in a way, what the extensible web manifesto—and examples like web components—are proposing is a meta-approach to how browsers implement new features. Instead of browser makers (in collaboration with standards bodies) creating new elements, UI widgets and APIs, developers will create new elements and UI widgets.

When Yehuda was describing this process, he compared it with the current situation. Currently, developers have to petition standards bodies begging them to implement some new kind of widget and eventually, if you’re lucky, browsers might implement it. At this point I interrupted to ask—somewhat tongue-in-cheek—”So if we get web components, what do we need standards bodies for?” Alex had an immediate response for that: standards bodies can look at what developers are creating, find the most common patterns, and implement them as new elements and widgets.

“I see,” I said. “So browsers and standards bodies will have a kind of ‘rough consensus’ based on …running code?”

“Yes!”, said Alex, laughing. “Jeremy Keith, ladies and gentlemen!”

So the idea with web components (and more broadly, the extensible web) is that developers will be able to create new elements with associated JavaScript functionality. Currently developers are creating new widgets using nothing but JavaScript. Ideally, web components will result in more declarative solutions and reduce our current reliance on JavaScript to do everything. I’m all for that.

But one thing slightly puzzled me. The idea of everyone creating whatever new elements they want isn’t a new one. That’s the whole idea behind XML (and by extension, XHTML) and yet the very same people who hated the idea of that kind of extensibility are the ones who are most eager about web components.

Playing devil’s advocate, I asked “How come the same people who hated RDF love web components?” (although what I really meant was RDFa—a means of extending HTML).

I got two answers. The first one was from Alex. Crucially, he said, a web component comes bundled with instructions on how it works. So it’s useful. That’s a big, big difference to the Tower of Babel scenario where everyone could just make up their own names for elements, but browsers have no idea what those names mean so effectively they’re meaningless.

That was the serious answer. The other answer I got was from Tim Berners-Lee. With a twinkle in his eye and an elbow in Alex’s ribs he said, “Well, these youngsters who weren’t around when we doing things with XML all want to do things with JSON now, which is a much cooler format because you can store number types in it. So that’s why they want to do everything in JavaScript.” Cheeky trickster!

Anyway, there was plenty of food for thought in the discussion of web components. This really is a radically new and different way of adding features to browsers. In theory, it shifts the balance of power much more to developers (who currently have to hack together everything using JavaScript). If it works, it will be A Good Thing and result in expanding HTML’s vocabulary with genuinely useful features. I fear there may be a rocky transition to this new way of thinking, and I worry about backwards compatibility, but I can’t help but admire the audacity of the plan.

The evening inevitably included a digression into the black hole of DRM. As always, the discussion got quite heated and I don’t think anybody was going to change their minds. I tried to steer things away from the ethical questions and back to the technical side of things by voicing my concerns with the security model of EME. Reading the excellent description by Henri, sentences like this should give you the heebie-jeebies:

Neither the browser nor the JavaScript program understand the bytes.

But the whole DRM discussion was, fortunately, curtailed by Anne who was ostensibly moderating the panel. Before it was though, Sir Tim made one final point. Because of the heat of the discussion, people were calling for us to separate the societal questions (around intellectual property and payment) from the technical ones (around encryption). But, Sir Tim pointed out, that separation isn’t really possible. Even something as simple as the hyperlink has political assumptions built in about the kind of society that would value being able to link resources together and share them around.

That’s an important point, well worth remembering: all software is political. That’s one of the reasons why I’d really appreciate an explicit documentation of design principles from the Technical Architecture Group.

Still, it was a very valuable event. Bruce has also written down his description of the evening. Many thanks to Dan and the rest of the TAG team for putting it together. I’m very glad I went along. As well as the panel discussion, it was really nice to chat to Paul and have the chance to congratulate Jeni in person on her appearance on her OBE.

Alas, I couldn’t stick around too long—I had to start making the long journey back to Brighton—so I said my goodbyes and exited. I didn’t have the opportunity to speak to Tim Berners-Lee directly, which is probably just as well: I’m sure I would’ve embarrassed myself by being a complete fanboy.

Laying The Groundwork For Extensibility—Smashing Coding

The authors of the Extensible Web Manifesto explain the thinking behind their …uh… thinking.

There’s a lot to like here, with some practical examples of where we’ve seen a disconnect between JavaScript APIs and declarative HTML (looking at you, Geolocation).

The Extensible Web Manifesto

An intriguing initiative to tighten up the loop between standards development and implementation.