Tags: web

207

sparkline

Clearleft.com is a progressive web app

What’s that old saying? The cobbler’s children have no shoes that work offline. Or something.

It’s been over a year since the Clearleft site relaunched and I listed some of the next steps I had planned:

Service worker. It’s a no-brainer. Now that the Clearleft site is (finally!) running on HTTPS, having a simple service worker to cache static assets like CSS, JavaScript and some images seems like the obvious next step.

You know how it is. Those no-brainer tasks are exactly the kind of thing that end up on a to-do list without ever quite getting to-done. Meanwhile I’ve been writing and speaking about how any website can be a progressive web app. I think Alanis Morissette used to sing about this sort of situation.

Enough is enough! Clearleft.com is now a progressive web app. It has a manifest file and a service worker script.

The service worker logic is fairly straightforward, and taken almost verbatim from Going Offline. As you navigate around the site, the service worker applies different logic depending on the kind of file you’re requesting:

  • Pages are served fresh from the network, falling back to the cache when there’s a problem.
  • Everything else is served from the cache where possible, resorting to the network only if there’s no match in the cache—quite the performance boost!

In both cases, if a page or a file is retrieved from the network, it’s gets put into a cache. I’ve got one cache for pages, and another for everything else. And even if a file is retrieved from that cache, I still fire off a fetch request to grab a fresh copy for the cache. So while there’s a chance that a stale file might be served up, it will only ever be slightly stale, and the next time it’s requested, it’ll be fresh.

In the worst-case scenario, when a page can’t be retrieved from the network or the cache, you end up seeing a custom offline page. There you can see a list of any pages that are cached (meaning you can revisit them even without an internet connection).

A custom offline page showing a list of URLs.

It’s not ideal—page titles would be friendlier than URLs—but it’s a start. I’m sure I’ll revisit it soon. Honest.

Oh, and after a year of procrastinating about doing this, guess how long it took? About half a day. Admittedly, this isn’t my first progressive web app, and the more you build ‘em, the easier it gets. Still, it’s a classic example of a small investment of time leading to a big improvement in performance and user experience.

If you think your company’s website could benefit from being a progressive web app (and believe me, it definitely could), you have a couple of options:

  1. Arm yourself with a copy of Going Offline and give it a go yourself. Or
  2. Get in touch with Clearleft. We can help you. (See, I can say that with a straight face now that we’re practicing what we preach.)

Either way, don’t dilly dally …like I did.

Document

A little while back, I showed Paul what I was working on with The Gęsiówka Story. I value his opinion and I really like the Bradshaw’s Guide project that he’s been working on. We’re both in complete agreement with Russell Davies’ call for an internet of unmonetisable enthusiasms. Call them side projects if you like, but for me, these are the things that the World Wide Web excels at.

These unomentisable enthusiasms/side projects are what got me hooked on the web in the first place. Fray.com—back when it was a website for personal stories—was what really made the web click for me. I had seen brochure sites, I had seen e-commerce sites, but it was seeing something built purely for the love of it that caused that lightbulb moment for me.

I told Paul about another site I remembered from that time (we’re talking about the mid-to-late nineties here). It was called Private Art. It was the work of one family, the children of Private Art Pranger who served in World War Two and wrote letters from the front. Without any expectations, I did a quick search, and amazingly, the site is still up!

Yes, it’s got tiled background images, and the framesetted content is in a pop-up window, but it works. The site hasn’t been updated for fifteen years but it works perfectly in a web browser today. That’s kind of amazing. We really shouldn’t take the longevity of our materials for granted. Could you imagine trying to open a word processing document from the late nineties on your computer today? You’d have a bad time.

Working on The Gęsiówka Story helped to remind me of some of the things that made me fall in love with the web in the first place. What I wrote about it is equally true of Private Art:

When we talk about documents on the web, we usually use the word “document” as a noun. But working on The Gęsiówka Story, I came to think of the word “document” as a verb.

The World Wide Web is a medium that’s works for quick, short-term lightweight bits of fun and also for long-term, deeper, slower, thoughtful archives of our collective culture.

The web is a many-splendoured thing.

Frustration

I had some problems with my bouzouki recently. Now, I know my bouzouki pretty well. I can navigate the strings and frets to make music. But this was a problem with the pickup under the saddle of the bouzouki’s bridge. So it wasn’t so much a musical problem as it was an electronics problem. I know nothing about electronics.

I found it incredibly frustrating. Not only did I have no idea how to fix the problem, but I also had no idea of the scope of the problem. Would it take five minutes or five days? Who knows? Not me.

My solution to a problem like this is to pay someone else to fix it. Even then I have to go through the process of having the problem explained to me by someone who understands and cares about electronics much more than me. I nod my head and try my best to look like I’m taking it all in, even though the truth is I have no particular desire to get to grips with the inner workings of pickups—I just want to make some music.

That feeling of frustration I get from having wiring issues with a musical instrument is the same feeling I get whenever something goes awry with my web server. I know just enough about servers to be dangerous. When something goes wrong, I feel very out of my depth, and again, I have no idea how long it will take the fix the problem: minutes, hours, days, or weeks.

I had a very bad day yesterday. I wanted to make a small change to the Clearleft website—one extra line of CSS. But the build process for the website is quite convoluted (and clever), automatically pulling in components from the site’s pattern library. Something somewhere in the pipeline went wrong—I still haven’t figured out what—and for a while there, the Clearleft website was down, thanks to me. (Luckily for me, Danielle saved the day …again. I’d be lost without her.)

I was feeling pretty down after that stressful day. I felt like an idiot for not knowing or understanding the wiring beneath the site.

But, on the other hand, considering I was only trying to edit a little bit of CSS, maybe the problem didn’t lie entirely with me.

There’s a principle underlying the architecture of the World Wide Web called The Rule of Least Power. It somewhat counterintuitively states that you should:

choose the least powerful language suitable for a given purpose.

Perhaps, given the relative simplicity of the task I was trying to accomplish, the plumbing was over-engineered. That complexity wouldn’t matter if I could circumvent it, but without the build process, there’s no way to change the markup, CSS, or JavaScript for the site.

Still, most of the time, the build process isn’t a hindrance, it’s a help: concatenation, minification, linting and all that good stuff. Most of my frustration when something in the wiring goes wrong is because of how it makes me feel …just like with the pickup in my bouzouki, or the server powering my website. It’s not just that I find this stuff hard, but that I also feel like it’s stuff I’m supposed to know, rather than stuff I want to know.

On that note…

Last week, Paul wrote about getting to grips with JavaScript. On the very same day, Brad wrote about his struggle to learn React.

I think it’s really, really, really great when people share their frustrations and struggles like this. It’s very reassuring for anyone else out there who’s feeling similarly frustrated who’s worried that the problem lies with them. Also, this kind of confessional feedback is absolute gold dust for anyone looking to write explanations or documentation for JavaScript or React while battling the curse of knowledge. As Paul says:

The challenge now is to remember the pain and anguish I endured, and bare that in mind when helping others find their own path through the knotted weeds of JavaScript.

HTTPS + service worker + web app manifest = progressive web app

I gave a quick talk at the Delta V conference in London last week called Any Site can be a Progressive Web App. I had ten minutes, but frankly I only needed enough time to say the title of the talk because, well, that was also the message.

There’s a common misconception that making a Progressive Web App means creating a Single Page App with an app-shell architecture. But the truth is that literally any website can benefit from the performance boost that results from the combination of HTTPS + Service Worker + Web App Manifest.

See how I define a progressive web app as being HTTPS + service worker + web app manifest? I’ve been doing that for a while. Here’s a post from last year called Progressing the web:

Literally any website can be a progressive web app:

That last step can be tricky if you’re new to service workers, but it’s not unsurmountable. It’s certainly a lot easier than completely rearchitecting your existing website to be a JavaScript-driven single page app.

Later I wrote a post called What is a Progressive Web App? where I compared the definition to responsive web design.

Regardless of the specifics of the name, what I like about Progressive Web Apps is that they have a clear definition. It reminds me of Responsive Web Design. Whatever you think of that name, it comes with a clear list of requirements:

  1. A fluid layout,
  2. Fluid images, and
  3. Media queries.

Likewise, Progressive Web Apps consist of:

  1. HTTPS,
  2. A service worker, and
  3. A Web App Manifest.

There’s more you can do in addition to that (just as there’s plenty more you can do on a responsive site), but the core definition is nice and clear.

But here’s the thing. Outside of the confines of my own website, it’s hard to find that definition anywhere.

On Google’s developer site, their definition uses adjectives like “reliable”, “fast”, and “engaging”. Those are all great adjectives, but more useful to a salesperson than a developer.

Over on the Mozilla Developer Network, their section on progressive web apps states:

Progressive web apps use modern web APIs along with traditional progressive enhancement strategy to create cross-platform web applications. These apps work everywhere and provide several features that give them the same user experience advantages as native apps. 

Hmm …I’m not so sure about that comparison to native apps (and I’m a little disturbed that the URL structure is /Apps/Progressive). So let’s click through to the introduction:

PWAs are web apps developed using a number of specific technologies and standard patterns to allow them to take advantage of both web and native app features.

Okay. Specific technologies. That’s good to hear. But instead of then listing those specific technologies, we’re given another list of adjectives (discoverable, installable, linkable, etc.). Again, like Google’s chosen adjectives, they’re very nice and desirable, but not exactly useful to someone who wants to get started making a progressive web app. That’s why I like to cut to the chase and say:

  • You need to be running on HTTPS,
  • Then you can add a service worker,
  • And don’t forget to add a web app manifest file.

If you do that, you’ve got a progressive web app. Now, to be fair, there’a lot that I’m leaving out. Your site should be fast. Your site should be responsive (it is, after all, on the web). There’s not much point mucking about with service workers if you haven’t sorted out the basics first. But those three things—HTTPS + service worker + web app manifest—are specifically what distinguishes a progressive web app. You can—and should—have a reliable, fast, engaging website before turning it into a progressive web app.

Jason has been thinking about progressive web apps a lot lately (he should write a book or something), and he said to me:

I agree with you on the three things that comprise a PWA, but as far as I can tell, you’re the first to declare it as such.

I was quite surprised by that. I always assumed that I was repeating the three ingredients of a progressive web app, not defining them. But looking through all the docs out there, Jason might be right. It’s surprising because I assumed it was obvious why those three things comprise a progressive web app—it’s because they’re testable.

Lighthouse, PWA Builder, Sonarwhal and other tools that evaluate your site will measure its progressive web app score based on the three defining factors (HTTPS, service worker, web app manifest). Then there’s Android’s Add to Home Screen prompt. Here finally we get a concrete description of what your site needs to do to pass muster:

  • Includes a web app manifest…
  • Served over HTTPS (required for service workers)
  • Has registered a service worker with a fetch event handler

(Although, as of this month, Chrome will no longer show the prompt automatically—you also have to write some JavaScript to handle the beforeinstallprompt  event).

Anyway, if you’re looking to turn your website into a progressive web app, here’s what you need to do (assuming it’s already performant and responsive):

  1. Switch over to HTTPS. Certbot can help you here.
  2. Add a web app manifest.
  3. Add a service worker to your site so that it responds even when there’s no network connection.

That last step might sound like an intimidating prospect, but help is at hand: I wrote Going Offline for exactly this situation.

Designing Progressive Web Apps by Jason Grigsby

It’s the afternoon of the second day of An Event Apart Seattle and Jason is talking about Designing Progressive Web Apps. These are my notes…

Jason wants to talk about a situation you might find yourself in. You’re in a room and in walks the boss, who says “We need a progressive web app.” Now everyone is asking themselves “What is a progressive web app?” Or maybe “How does the CEO even know about progressive web apps?”

Well, trade publications are covering progressive web apps. Lots of stats and case studies are being published. When executives see this kind of information, they don’t want to get left out. Jason keeps track of this stuff at PWA Stats.

Answering the question “What is a progressive web app?” is harder than it should be. The phrase was coined by Frances Berriman and Alex Russell. They listed ten characteristics that defined progressive web apps. The “linkable” and “progressive” characteristics are the really interesting and new characteristics. We’ve had technologies before (like Adobe Air) that tried to make app-like experiences, but they weren’t really of the web. Progressive web apps are different.

Despite this list of ten characteristics, even people who are shipping progressive web apps find it hard to define the damn thing. The definition on Google’s developer site keeps changing. They reduced the characteristics from ten to six. Then it became “reliable, fast, and engaging.” What does that mean? Craigslist is reliable, fast, and engaging—does that mean it’s a progressive web app.

The technical definition is useful (kudos to me, says Jason):

  1. HTTPS
  2. service worker
  3. manifest file

If you don’t have those three things, it’s not a progressive web app.

We should definitely use HTTPS if we want make life harder for the NSA. Also browser makers are making APIs available only under HTTPS. By July, Chrome will mark HTTP sites as insecure. Every site should be under HTTPS.

Service workers are where the power is. They act as a proxy. They allow us to say what we want to cache, what we want to go out to the network for; things that native apps have been able to do for a while. With progressive web apps we can cache the app shell and go to the network for content. Service workers can provide a real performance boost.

A manifest file is simply a JSON file. It’s short and clear. It lists information about the app: icons, colours, etc.

Once you provide those three things, you get benefits. Chrome and Opera on Android will prompt to add the app to the home screen.

So that’s what’s required for progressive web apps, but there’s more to them than that (in the same way there’s more to responsive web design than the three requirements in the baseline definition).

The hype around progressive web apps can be a bit of a turn-off. It certainly was for Jason. When he investigated the technologies, he wondered “What’s the big deal?” But then he was on a panel at a marketing conference, and everyone was talking about progressive web apps. People’s expectations of what you could do on the web really hadn’t caught up with what we can do now, and the phrase “progressive web app” gives us a way to encapsulate that. As Frances says, the name isn’t for us; it’s for our boss or marketer.

Jason references my post about using the right language for the right audience.

Should you have a progressive web app? Well, if you have a website, then the answer is almost certainly “Yes!” If you make money from that website, the answer is definitely “Yes!”

But there’s a lot of FUD around progressive web apps. It brings up the tired native vs. web battle. Remember though that not 100% of your users or customers have your app installed. And it’s getting harder to convince people to install apps. The average number of apps installed per month is zero. But your website is often a customer’s first interaction with your company. A better web experience can only benefit you.

Often, people say “The web can’t do…” but a lot of the time that information is out of date. There are articles out there with outdated information. One article said that progressive web apps couldn’t access the camera, location, or the fingerprint sensor. Yet look at Instagram’s progressive web app: it accesses the camera. And just about every website wants access to your location these days. And Jason knows you can use your fingerprint to buy things on the web because he accidentally bought socks when he was trying to take a screenshot of the J.Crew website on his iPhone. So the author of that article was just plain wrong. The web can do much more than we think it can.

Another common objection is “iOS doesn’t support progressive web apps”. Well, as of last week that is no longer true. But even when that was still true, people who had implemented progressive web apps were seeing increased conversion even on iOS. That’s probably because, if you’ve got the mindset for building a progressive web app, you’re thinking deeply about performance. In many ways, progressive web apps are a trojan horse for performance.

These are the things that people think about when it comes to progressive web apps:

  1. Making it feel like a app
  2. Installation and discovery
  3. Offline mode
  4. Push notifications
  5. Beyond progressive web app

Making it feel like a app

What is an app anyway? Nobody can define it. Once again, Jason references my posts on this topic (how “app” is like “obscenity” or “brunch”).

A lot of people think that “app-like” means making it look native. But that’s a trap. Which operating system will you choose to emulate? Also, those design systems change over time. You should define your own design. Make it an exceptional experience regardless of OS.

It makes more sense to talk in terms of goals…

Goal: a more immersive experience.

Possible solution: removing the browser chrome and going fullscreen?

You can define this in the manifest file. But as you remove the browser chrome, you start to lose things that people rely on: the back button, the address bar. Now you have to provide that functionality. If you move to a fullscreen application you need to implement sharing, printing, and the back button (and managing browser history is not simple). Remember that not every customer will add your progressive web app to their home screen. Some will have browser chrome; some won’t.

Goal: a fast fluid experience.

Possible solution: use an app shell model.

You want smooth pages that don’t jump around as the content loads in. The app shell makes things seem faster because something is available instantly—it’s perceived performance. Basically you’re building a single page application. That’s a major transition. But thankfully, you don’t have to do it! Progressive web apps don’t have to be single page apps.

Goal: an app with personality.

Possible solution: Animated transitions and other bits of UI polish.

Really, it’s all about delight.

Installation and discovery

In your manifest file you can declare a background colour for the startup screen. You can also declare a theme colour—it’s like you’re skinning the browser chrome.

You can examine the manifest files for a site in Chrome’s dev tools.

Once you’ve got a progressive web app, some mobile browsers will start prompting users to add it to their home screen. Firefox on Android displays a little explainer the first time you visit a progressive web app. Chrome and Opera have add-to-homescreen banners which are a bit more intrusive. The question of when they show up keeps changing. They use a heuristic to decide this. The heuristic has been changed a few times already. One thing you should consider is suppressing the banner until it’s an optimal time. Flipkart do this: they only allow it on the order confirmation page—the act of buying something makes it really likely that someone will add the progressive web app to their home screen.

What about app stores? We don’t need them for progressive web apps—they’re on the web. But Microsoft is going to start adding progressive web apps to their app store. They’ve built a site called PWA Builder to help you with your progressive web app.

On the Android side, there’s Trusted Web Activity which is kind of like PhoneGap—it allows you to get a progressive web app into the Android app store.

But remember, your progressive web app is your website so all the normal web marketing still applies.

Offline mode

A lot of organisations say they have no need for offline functionality. But everyone has a need for some offline capability. At the very least, you can provide a fallback page, like Trivago’s offline maze game.

You can cache content that has been recently viewed. This is what Jason does on the Cloud Four site. They didn’t want to make any assumptions about what people might want, so they only cache pages as people browse around the site.

If you display cached information, you might want to display how stale the information is e.g. for currency exchange rates.

Another option is to let people choose what they want to keep offline. The Financial Times does this. They also pre-cache the daily edition.

If you have an interactive application, you could queue tasks and then carry them out when there’s a connection.

Or, like Slack does, don’t let people write something if they’re offline. That’s better than letting someone write something and then losing it.

Workbox is a handy library for providing offline functionality.

Push notifications

The JavaScript for push notifications is relatively easy, says Jason. It’s the back-end stuff that’s hard. That’s because successful push notifications are personalised. But to do that means doing a lot more work on the back end. How do you integrate with preferences? Which events trigger notifications?

There are third-party push notification services that take care of a lot of this for you. Jason has used OneSignal.

Remember that people are really annoyed by push notifications. Don’t ask for permission immediately. Don’t ask someone to marry you on a first date. On Cloud Four’s blog, they only prompt after the user has read an article.

Twitter’s progressive web app does this really well. It’s so important that you do this well: if a user says “no” to your push notification permission request, you will never be able to ask them again. There used to be three options on Chrome: allow, block, or close. Now there are just two: allow or block.

Beyond progressive web apps

There are a lot of APIs that aren’t technically part of progressive web apps but get bundled in with them. Like the Credentials Management API or the Payment Request API (which is converging with ApplePay).

So how should you plan your progressive web app launch? Remember it’s progressive. You can keep adding features. Each step along the way, you’re providing value to people.

Start with some planning and definition. Get everyone in a room and get a common definition of what the ideal progressive web app would look like. Remember there’s a continuum of features for all five of the things that Jason has outlined here.

Benchmark your existing site. It will help you later on.

Assess your current website. Is the site reasonably fast? Is it responsive? Fix those usability issues first.

Next, do the baseline. Switch to HTTPS. Add a manifest file. Add a service worker. Apart from the HTTPS switch, this can all be done on the front end. Don’t wait for all three: ship each one when they’re ready.

Then do front-end additions: pre-caching pages, for example.

Finally, there are the larger initiatives (with more complex APIs). This is where your initial benchmarking really pays off. You can demonstrate the value of what you’re proposing.

Every step on the path to a progressive web app makes sense on its own. Figure out where you want to go and start that journey.

See also:

Faraway February

For the shortest month of the year, February managed to pack a lot in. I was away for most of the month. I had the great honour of being asked back to speak at Webstock in New Zealand this year—they even asked me to open the show!

I had no intention of going straight to New Zealand and then turning around to get on the first flight back, so I made sure to stretch the trip out (which also helps to mitigate the inevitable jet lag). Jessica and I went to Hong Kong first, stayed there for a few nights, then went on Sydney for a while (and caught up with Charlotte while we were out there), before finally making our way to Wellington. Then, after Webstock was all wrapped up, we retraced the same route in reverse. Many flat whites, dumplings, and rays of sunshine later, we arrived back in the UK.

As well as giving the opening keynote at Webstock, I did a full-day workshop, and I also ran a workshop in Hong Kong on the way back. So technically it was a work trip, but I am extremely fortunate that I get to go on adventures like this and still get to call it work.

Words I wrote in 2017

I wrote 78 blog posts in 2017. That works out at an average of six and a half blog posts per month. I’ll take it.

Here are some pieces of writing from 2017 that I’m relatively happy with:

Going Rogue. A look at the ethical questions raised by Rogue One

In AMP we trust. My unease with Google’s AMP format was growing by the day.

A minority report on artificial intelligence. Revisiting two of Spielberg’s films after a decade and a half.

Progressing the web. I really don’t want progressive web apps to just try to imitate native apps. They can be so much more.

CSS. Simple, yes, but not easy.

Intolerable. A screed. I still get very, very angry when I think about how that manifestbro duped people.

Акула. Recounting a story told by a taxi driver.

Hooked and booked. Does A/B testing lead to dark patterns?

Ubiquity and consistency. Different approaches to building on the web.

I hope there’s something in there that you like. It always a nice bonus when other people like something I’ve written, but I write for myself first and foremost. Writing is how I figure out what I think. I will, of course, continue to write and publish on my website in 2018. I’d really like it if you did the same.

Origin story

In an excellent piece called The First Web Apps: 5 Apps That Shaped the Internet as We Know It, Matthew Guay wrote:

The world wide web wasn’t supposed to be this fun. Berners-Lee imagined the internet as a place to collaborate around text, somewhere to share research data and thesis papers.

In his somewhat confused talk at FFConf this year, James Kyle said:

The web was designed to share documents.

Douglas Crockford said

The web was not designed to do any of things it is doing. It was intended to be a simple—even primitive—document retrieval system.

Some rando on Hacker News declared:

Essentially every single aspect of the web is terrible. It was designed as a static document presentation system with hyperlinks.

It appears to be a universally accepted truth. The web was designed for sharing documents, and was never meant for the kind of applications we can build these days.

I don’t think that’s quite right. I think it’s fairer to say that the first use case for the web was document retrieval. And yes, that initial use case certainly influenced the first iteration of HTML. But right from the start, the vision for the web wasn’t constrained by what it was being asked to do at the time. (I mean, if you need an example of vision, Tim Berners-Lee called it the World Wide Web when it was just on one computer!)

The original people working on the web—Tim Berners-Lee, Robert Cailliau, Jean-Francois Groff, etc.—didn’t to try define the edges of what the web would be capable of. Quite the opposite. All of them really wanted a more interactive read-write web where documents could not only be read, but also edited and updated.

As for the idea of having a programming language in browsers (as well as a markup language), Tim Berners-Lee was all for it …as long as it could be truly ubiquitous.

To say that the web was made for sharing documents is like saying that the internet was made for email. It’s true in the sense that it was the most popular use case, but that never defined the limits of the system.

The secret sauce of the internet lies in its flexibility—it’s a deliberately dumb network that doesn’t care about the specifics of what runs on it. This lesson was then passed on to the web—another deliberately simple system designed to be agnostic to use cases.

It’s true that the web of today is very, very different to its initial incarnation. We got CSS; we got JavaScript; HTML has evolved; HTTP has evolved; URLs have …well, cool URIs don’t change, but you get the idea. The web is like the ship of Theseus—so much of it has been changed and added to over time. That doesn’t mean its initial design was flawed—just the opposite. It means that its initial design wasn’t unnecessarily rigid. The simplicity of the early web wasn’t a bug, it was a feature.

The web (like the internet upon which it runs) was designed to be flexible, and to adjust to future use-cases that couldn’t be predicted in advance. The best proof of this flexibility is the fact that we can and do now build rich interactive applications on the World Wide Web. If the web had truly been designed only for documents, that wouldn’t be possible.

What is a Progressive Web App?

It seems like any new field goes through an inevitable growth spurt that involves “defining the damn thing.” For the first few years of the IA Summit, every second presentation seemed to be about defining what Information Architecture actually is. See also: UX. See also: Content Strategy.

Now it seems to be happening with Progressive Web Apps …which is odd, considering the damn thing is defined damn well.

I’ve written before about the naming of Progressive Web Apps. On the whole, I think it’s a pretty good term, especially if you’re trying to convince the marketing team.

Regardless of the specifics of the name, what I like about Progressive Web Apps is that they have a clear definition. It reminds me of Responsive Web Design. Whatever you think of that name, it comes with a clear list of requirements:

  1. A fluid layout,
  2. Fluid images, and
  3. Media queries.

Likewise, Progressive Web Apps consist of:

  1. HTTPS,
  2. A service worker, and
  3. A Web App Manifest.

There’s more you can do in addition to that (just as there’s plenty more you can do on a responsive site), but the core definition is nice and clear.

Except, for some reason, that clarity is being lost.

Here’s a post by Ben Halpern called What the heck is a “Progressive Web App”? Seriously.

I have a really hard time describing what a progressive web app actually is.

He points to Google’s intro to Progressive Web Apps:

Progressive Web Apps are user experiences that have the reach of the web, and are:

  • Reliable - Load instantly and never show the downasaur, even in uncertain network conditions.
  • Fast - Respond quickly to user interactions with silky smooth animations and no janky scrolling.
  • Engaging - Feel like a natural app on the device, with an immersive user experience.

Those are great descriptions of the benefits of Progressive Web Apps. Perfect material for convincing your clients or your boss. But that appears on developers.google.com …surely it would be more beneficial for that audience to know the technologies that comprise Progressive Web Apps?

Ben Halpern again:

Google’s continued use of the term “quality” in describing things leaves me with a ton of confusion. It really seems like they want PWA to be a general term that doesn’t imply any particular implementation, and have it be focused around the user experience, but all I see over the web is confusion as to what they mean by these things. My website is already “engaging” and “immersive”, does that mean it’s a PWA?

I think it’s important to use the right language for the right audience.

If you’re talking to the business people, tell them about the return on investment you get from Progressive Web Apps.

If you’re talking to the marketing people, tell them about the experiential benefits of Progressive Web Apps.

But if you’re talking to developers, tell them that a Progressive Web App is a website served over HTTPS with a service worker and manifest file.

Installing Progressive Web Apps

When I was testing the dConstruct Audio Archive—which is now a Progressive Web App—I noticed some interesting changes in how Chrome on Android offers the “add to home screen” prompt.

It used to literally say “add to home screen.”

Getting the “add to home screen” prompt for https://huffduffer.com/ on Android Chrome. And there’s the “add to home screen” prompt for https://html5forwebdesigners.com/ HTTPS + manifest.json + Service Worker = “Add to Home Screen” prompt. Add to home screen.

Now it simply says “add.”

The dConstruct Audio Archive is now a Progressive Web App

I vaguely remember there being some talk of changing the labelling, but I could’ve sworn it was going to change to “install”. I’ve got to be honest, just having the word “add” doesn’t seem to provide much context. Based on the quick’n’dirty usability testing I did with some co-workers, it just made things confusing. “Add what?” “What am I adding?”

Additionally, the prompt appeared immediately on the first visit to the site. I thought there was supposed to be an added “engagement” metric in order for the prompt to appear; that the user needs to visit the site more than once.

You’d think I’d be happy that users will be presented with the home-screen prompt immediately, but based on the behaviour I saw, I’m not sure it’s a good thing. Here’s what I observed:

  1. The user types the URL archive.dconstruct.org into the address bar.
  2. The site loads.
  3. The home-screen prompt slides up from the bottom of the screen.
  4. The user immediately moves to dismiss the prompt (cue me interjecting “Don’t close that!”).

This behaviour is entirely unsurprising for three reasons:

  1. We web designers and web developers have trained users to dismiss overlays and pop-ups if they actually want to get to the content. Nobody’s going to bother to actually read the prompt if there’s a 99% chance it’s going to say “Sign up to our newsletter!” or “Take our survey!”.
  2. The prompt appears below the “line of death” so there’s no way to tell it’s a browser or OS-level dialogue rather than a JavaScript-driven pop-up from the site.
  3. Because the prompt now appears on the first visit, no trust has been established between the user and the site. If the prompt only appeared on later visits (or later navigations during the first visit) perhaps it would stand a greater chance of survival.

It’s still possible to add a Progressive Web App to the home screen, but the option to do that is hidden behind the mysterious three-dots-vertically-stacked icon (I propose we call this the shish kebab icon to distinguish it from the equally impenetrable hamburger icon).

I was chatting with Andreas from Mozilla at the View Source conference last week, and he was filling me in on how Firefox on Android does the add-to-homescreen flow. Instead of a one-time prompt, they’ve added a persistent icon above the “line of death” (the icon is a combination of a house and a plus symbol).

When a Firefox 58 user arrives on a website that is served over HTTPS and has a valid manifest, a subtle badge will appear in the address bar: when tapped, an “Add to Home screen” confirmation dialog will slide in, through which the web app can be added to the Android home screen.

This kind of badging also has issues (without the explicit text “add to home screen”, the user doesn’t know what the icon does), but I think a more persistently visible option like this works better than the a one-time prompt.

Firefox is following the lead of the badging approach pioneered by the Samsung Internet browser. It provides a plus symbol that, when pressed, reveals the options to add to home screen or simply bookmark.

What does it mean to be an App?

I don’t think Chrome for Android has any plans for this kind of badging, but they are working on letting the site authors provide their own prompts. I’m not sure this is such a good idea, given our history of abusing pop-ups and overlays.

Sadly, I feel that any solution that relies on an unrequested overlay is doomed. That’s on us. The way we’ve turned browsing the web—especially on mobile—into a frustrating chore of dismissing unwanted overlays is a classic tragedy of the commons. We blew it. Users don’t trust unrequested overlays, and I can’t blame them.

For what it’s worth, my opinion is that ambient badging is a better user experience than one-time prompts. That opinion is informed by a meagre amount of testing though. I’d love to hear from anyone who’s been doing more detailed usability testing of both approaches. I assume that Google, Mozilla, and Samsung are doing this kind of testing, and it would be really great to see the data from that (hint, hint).

But it might well be that ambient badging is just too subtle to even be noticed by the user.

On one end of the scale you’ve got the intrusiveness of an add-to-home-screen prompt, but on the other end of the scale you’ve got the discoverability problem of a subtle badge icon. I wonder if there might be a compromise solution—maybe a badge icon that pulses or glows on the first or second visit?

Of course that would also need to be thoroughly tested.

Pattern Libraries, Performance, and Progressive Web Apps

Ever since its founding in 2005, Clearleft has been laser-focused on user experience design.

But we’ve always maintained a strong front-end development arm. The front-end development work at Clearleft is always in service of design. Over the years we’ve built up a wealth of expertise on using HTML, CSS, and JavaScript to make better user experiences.

Recently we’ve been doing a lot of strategic design work—the really in-depth long-term engagements that begin with research and continue through to design consultancy and collaboration. That means we’ve got availability for front-end development work. Whether it’s consultancy or production work you’re looking for, this could be a good opportunity for us to work together.

There are three particular areas of front-end expertise we’re obsessed with…

Pattern Libraries

We caught the design systems bug years ago, way back when Natalie started pioneering pattern libraries as our primary deliverable (or pattern portfolios, as we called them then). This approach has proven effective time and time again. We’ve spent years now refining our workflow and thinking around modular design. Fractal is the natural expression of this obsession. Danielle and Mark have been working flat-out on version 2. They’re very eager to share everything they’ve learned along the way …and help others put together solid pattern libraries.

Danielle Huntrods Mark Perkins

Performance

Thinking about it, it’s no surprise that we’re crazy about performance at Clearleft. Like I said, our focus on user experience, and when it comes to user experience on the web, nothing but nothing is more important than performance. The good news is that the majority of performance fixes can be done on the front end—images, scripts, fonts …it’s remarkable how much a good front-end overhaul can make to the bottom line. That’s what Graham has been obsessing over.

Graham Smith

Progressive Web Apps

Over the years I’ve found myself getting swept up in exciting new technologies on the web. When Clearleft first formed, my head was deep into DOM Scripting and Ajax. Half a decade later it was HTML5. Now it’s service workers. I honestly think it’s a technology that could be as revolutionary as Ajax or HTML5 (maybe I should write a book to that effect).

I’ve been talking about service workers at conferences this year, and I can’t hide my excitement:

There’s endless possibilities of what you can do with this technology. It’s very powerful.

Combine a service worker with a web app manifest and you’ve got yourself a Progressive Web App. It’s not just a great marketing term—it’s an opportunity for the web to truly excel at delivering the kind of user experiences previously only associated with native apps.

Jeremy Keith

I’m very very keen to work with companies and organisations that want to harness the power of service workers and Progressive Web Apps. If that’s you, get in touch.

Whether it’s pattern libraries, performance, or Progressive Web Apps, we’ve got the skills and expertise to share with you.

Sonic sparklines

I’ve seen some lovely examples of the Web Audio API recently.

At the Material conference, Halldór Eldjárn demoed his Poco Apollo project. It generates music on the fly in the browser to match a random image from NASA’s Apollo archive on Flickr. Brian Eno, eat your heart out!

At Codebar Brighton a little while back, local developer Luke Twyman demoed some of his audio-visual work, including the gorgeous Solarbeat—an audio orrery.

The latest issue of the Clearleft newsletter has some links on sound design in interfaces:

I saw Ruth give a fantastic talk on the Web Audio API at CSS Day this year. It had just the right mixture of code and inspiration. I decided there and then that I’d have to find some opportunity to play around with web audio.

As ever, my own website is the perfect playground. I added an audio Easter egg to adactio.com a while back, and so far, no one has noticed. That’s good. It’s a very, very silly use of sound.

In her talk, Ruth emphasised that the Web Audio API is basically just about dealing with numbers. Lots of the examples of nice usage are the audio equivalent of data visualisation. Data sonification, if you will.

I’ve got little bits of dataviz on my website: sparklines. Each one is a self-contained SVG file. I added a script element to the SVG with a little bit of JavaScript that converts numbers into sound (I kind of wish that the script were scoped to the containing SVG but that’s not the way JavaScript in SVG works—it’s no different to putting a script element directly in the body). Clicking on the sparkline triggers the sound-playing function.

It sounds terrible. It’s like a theremin with hiccups.

Still, I kind of like it. I mean, I wish it sounded nicer (and I’m open to suggestions on how to achieve that—feel free to fork the code), but there’s something endearing about hearing a month’s worth of activity turned into a wobbling wave of sound. And it’s kind of fun to hear how a particular tag is used more frequently over time.

Anyway, it’s just a silly little thing, but anywhere you spot a sparkline on my site, you can tap it to hear it translated into sound.

Posting to my site

I was idly thinking about the different ways I can post to adactio.com. I decided to count the ways.

Admin interface

This is the classic CMS approach. In my case the CMS is a crufty hand-rolled affair using PHP and MySQL that I wrote years ago. I log in to an admin interface and fill in a form, putting the text of my posts into a textarea. In truth, I usually write in a desktop text editor first, and then paste that into the textarea. That’s what I’m doing now—copying and pasting Markdown from the Typed app.

Directly from my site

If I’m logged in, I get a stripped down posting interface in the notes section of my site.

Notes posting interface

Bookmarklet

This is how I post links. When I’m at a URL I want to bookmark, I hit the “Bookmark it” bookmarklet in my browser’s bookmarks bar. That pops open a version of the admin interface tailored specifically for links. I really, really like bookmarklets. The one big downside is that they don’t work on mobile.

Text message

This is something I knocked together at Indie Web Camp Brighton 2015 using the Twilio API. It’s handy for posting notes if I’m travelling somewhere and data is at a premium. But I don’t use it that often.

Instagram

Thanks to Aaron’s OwnYourGram service—and the fact that my site has a micropub endpoint—I can post images from Instagram to my site. This used to happen instantaneously but Instagram changed their API rules for the worse. Between that and their shitty “algorithmic” timeline, I find myself using the service less and less. At this point I’m only on their for the doggos.

Swarm

Like OwnYourGram, Aaron’s OwnYourSwarm allows me to post check-ins and photos from the Swarm app to my site. Again, micropub makes it all possible.

OwnYourGram and OwnYourSwarm are very similar and could probably be abstracted into a generic service for posting from third-party apps to micropub endpoints. I’d quite like to post my check-ins on Untappd to my site.

Other people’s admin interfaces

Thanks to rel="me" and IndieAuth, I can log into other people’s posting interfaces using my own website as the log-in, and post to my micropub endpoint, like this. Quill is a good example of this. I don’t use it that much, but I really should—the editor interface is quite Medium-like in its design.

Anyway, those are the different ways I can update my website that I can think of right now.

Syndication

In terms of output, I’ve got a few different ways of syndicating what I post here:

Just so you know, if you comment on one of my posts on Facebook, I probably won’t see it. But if you reply to a copy of one of posts on Twitter or Instagram, it will show up over here on adactio.com thanks to the magic of Brid.gy and webmention.

The magical and the mundane

The iPhone—and by extension, the smartphone—is a decade old. Ian Bogost has written an interesting piece in The Atlantic charting our changing relationship with the technology.

First, it was like a toy dog:

A device that could be cared for, and conspicuously so.

Then, it was like a cigarette:

A nervous tic, facilitated by a handheld apparatus that releases relief when operated.

Later, it was like a rosary:

Its toy-dog quirks having been tamed, its compulsive nature having been accepted, the iPhone became the magic wand by which all worldly actions could be performed, all possible information acquired.

Finally, it simply becomes …a rectangle.

Abstract, as a shape. Flat, as a surface. But suggestive of so much. A table for community. A door for entry, or for exit. A window for looking out of, or a picture for looking into. A movie screen for distraction, or a cradle for comfort, or a bed for seduction.

Design dissolves in behaviour. This is something that Ben wrote about recently in his excellent Slapdashery series: “Everything’s amazing and nobody’s happy.”

Technology tweaks our desire for novelty; but as soon as we get it we’re usually bored. There are no technologies that I can think of that haven’t become mundane.

This is something I touched on in my talk last year at An Event Apart. There’s a thread throughout the talk about Arthur C. Clarke, and of course I quote his third law:

Any sufficiently advanced technology is indistinguishable from magic.

I propose an addendum to that:

Any sufficiently advanced technology is indistinguishable from magic at first.

The magical quickly becomes the mundane. That’s exactly the point that Louis CK is making in the piece that Ben references.

Seven years ago Frank wrote his wonderful essay There Is A Horse In The Apple Store:

I have a term called a “tiny pony.” It is a thing that is exceptional that no one, for whatever reason, notices. Or, conversely, it is an exceptional thing that everyone notices, but quickly grows acclimated to despite the brilliance of it all.

We are surrounded by magical tiny ponies. I mean, just think: right now you are reading some words at a URL on the World Wide Web. Even more magically, I just published some words at my own URL on the World Wide Web. That still blows my mind! I hope I never lose that feeling.

Progressing the web

Frances has written up some of the history behind her minting of the term “progressive web app”. She points out that accuracy is secondary to marketing:

I keep seeing folks (developers) getting all smart-ass saying they should have been PW “Sites” not “Apps” but I just want to put on the record that it doesn’t matter. The name isn’t for you and worrying about it is distraction from just building things that work better for everyone. The name is for your boss, for your investor, for your marketeer.

Personally, I think “progressive web app” is a pretty good phrase—two out of three words in it are spot on. I really like the word “progressive”, with its echoes of progressive enhancement. I really, really like the word “web”. But, yeah, I’m one of those smart-asses who points out that the “app” part isn’t great.

That’s not just me being a pedant (or, it’s not only me being a pedant). I’ve seen people who were genuinely put off investigating the technologies behind progressive web apps because of the naming.

Here’s an article with the spot-on title Progressive Web Apps — The Next Step In Responsive Web Design:

Late last week, Smashing Magazine, one of the largest and most influential online publications for web design, posted on Facebook that their website was “now running as a Progressive Web App.”

Honestly, I didn’t think much of it. Progressive Web Apps are for the hardcore web application developers creating the next online cloud-based Photoshop (complicated stuff), right? I scrolled on and went about my day.

And here’s someone feeling the cognitive dissonance of turning a website into a progressive web app, even though that’s exactly the right thing to do:

My personal website is a collection of static HTML files and is also a progressive web app. Transforming it into a progressive web app felt a bit weird in the beginning because it’s not an actual application but I wanted to be one of the cool kids, and PWAs still offer a lot of additional improvements.

Still, it could well be that these are the exceptions and that most people are not being discouraged by the “app” phrasing. I certainly hope that there aren’t more people out there thinking “well, progressive web apps aren’t for me because I’m building a content site.”

In short, the name might not be perfect but it’s pretty damn good.

What I find more troubling is the grouping of unrelated technologies under the “progressive web app” banner. If Google devrel events were anything to go by, you’d be forgiven for thinking that progressive web apps have something to do with AMP or Polymer (they don’t). One of the great things about progressive web apps is that they are agnostic to tech stacks. Still, I totally get why Googlers would want to use the opportunity to point to their other projects.

Far more troubling is the entanglement of the term “progressive web app” with the architectural choice of “single page app”. I’m not the only one who’s worried about this.

Here’s the most egregious example: an article on Hacker Noon called Before You Build a PWA You Need a SPA.

No! Not true! Literally any website can be a progressive web app:

That last step can be tricky if you’re new to service workers, but it’s not unsurmountable. It’s certainly a lot easier than completely rearchitecting your existing website to be a JavaScript-driven single page app.

Alas, I think that many of the initial poster-children for progressive web apps gave the impression that you had to make a completely separate app/site at a different URL. It was like a return to the bad old days of m. sites for mobile. The Washington Post’s progressive web app (currently offline) went so far as to turn away traffic from the “wrong” browsers. This is despite the fact that the very first item in the list of criteria for a progressive web app is:

Responsive: to fit any form factor

Now, I absolutely understand that the immediate priority is to demonstrate that a progressive web app can compete with a native mobile app in terms of features (and trounce it in terms of installation friction). But I’m worried that in our rush to match what native apps can do, we may end up ditching the very features that make the web a universally-accessible medium. Killing URLs simply because native apps don’t have URLs is a classic example of throwing the baby out with the bath water:

Up until now I’ve been a big fan of Progressive Web Apps. I understood them to be combining the best of the web (responsiveness, linkability) with the best of native (installable, connectivity independent). Now I see that balance shifting towards the native end of the scale at the expense of the web’s best features. I’d love to see that balance restored with a little less emphasis on the “Apps” and a little more emphasis on the “Web.” Now that would be progressive.

If the goal of the web is just to compete with native, then we’ve set the bar way too low.

So if you’ve been wary of investing the technologies behind progressive web apps because you’re “just” building a website, please try to see past the name. As Frances says:

It’s marketing, just like HTML5 had very little to do with actual HTML. PWAs are just a bunch of technologies with a zingy-new brandname.

Literally any website can—and should—be a progressive web app. Don’t let anyone tell you otherwise.

I was at an event last year where I heard Chris Heilmann say that you shouldn’t make your blog into a progressive web app. I couldn’t believe what I was hearing. He repeats that message in this video chat:

When somebody, for example, turns their blog into a PWA, I don’t see the point. I don’t want to have that icon on my homepage. This doesn’t make any sense to me.

Excuse me!? Just because you don’t want to have someone’s icon on your home screen, that person shouldn’t be using state-of-the-art technologies!? Excuse my French, but Fuck. That. Shit!

Our imaginations have become so limited by what native mobile apps currently do that we can’t see past merely imitating the status quo like a sad cargo cult.

I don’t want the web to equal native; I want the web to surpass it. I, for one, would prefer a reality where my home screen isn’t filled with the icons of startups and companies that have fulfilled the criteria of the gatekeepers. But a home screen filled with the faces of people who didn’t have to ask anyone’s permission to publish? That’s what I want!

Like Frances says:

Remember, this is for everyone.

Talking with the tall man about poetry

When I started making websites in the 1990s, I had plenty of help. The biggest help came from the ability to view source on any web page—the web was a teacher of itself. I also got plenty of help from people who generously shared their knowledge and experience. There was Jeffrey’s Ask Dr. Web, Steve Champeon’s WebDesign-L mailing list, and Jeff Veen’s articles on Webmonkey. Years later, I was able to meet those people. That was a real privilege.

I’ve known Jeff for over a decade now. He’s gone from Adaptive Path to Google to TypeKit to Adobe to True Ventures, and it’s always fascinating to catch up with him and get his perspective on life, the universe, and everything.

He started up a podcast called Presentable about a year ago. It’s worth having a dig through the archives to have a listen to his chats with people like Andy, Jason, Anna, and Jessica. I was honoured when Jeff asked me to be on the show.

We ended up having a really good chat. It’s out now as Episode 25: The Tenuous Resilience of the Open Web. I really enjoyed having a good ol’ natter, and I hope you might enjoy listening to it.

‘Sfunny, but I feel like a few unplanned themes came up a few times. We ended up talking about art, but also about the scientific aspects of design. I couldn’t help but be reminded of the title of Jeff’s classic book, The Art and Science of Web Design.

We also talked about my most recent book, Resilient Web Design, and that’s when I noticed another theme. When discussing the web-first nature of publishing the book, I described the web version as the canonical version and all the other formats as copies that were generated from that. That sounds a lot like how I describe the indie web—something else we discussed—where you have the canonical instance on your own site but share copies on social networks: Publish on Own Site, Syndicate Elsewhere—POSSE.

We also talked about technologies, and it’s entirely possible that we sound like two old codgers on the front porch haranguing those damn kids on the lawn. You can be the judge of that. The audio is available for your huffduffing pleasure. If you enjoy listening to it half as much as I enjoyed doing it, then I enjoyed it twice as much as you.

Month maps

One of the topics I enjoy discussing at Indie Web Camps is how we can use design to display activity over time on personal websites. That’s how I ended up with sparklines on my site—it was the a direct result of a discussion at Indie Web Camp Nuremberg a year ago:

During the discussion at Indie Web Camp, we started looking at how silos design their profile pages to see what we could learn from them. Looking at my Twitter profile, my Instagram profile, my Untappd profile, or just about any other profile, it’s a mixture of bio and stream, with the addition of stats showing activity on the site—signs of life.

Perhaps the most interesting visual example of my activity over time is on my Github profile. Halfway down the page there’s a calendar heatmap that uses colour to indicate the amount of activity. What I find interesting is that it’s using two axes of time over a year: days of the month across the X axis and days of the week down the Y axis.

I wanted to try something similar, but showing activity by time of day down the Y axis. A month of activity feels like the right range to display, so I set about adding a calendar heatmap to monthly archives. I already had the data I needed—timestamps of posts. That’s what I was already using to display sparklines. I wrote some code to loop over those timestamps and organise them by day and by hour. Then I spit out a table with days for the columns and clumps of hours for the rows.

Calendar heatmap on Dribbble

I’m using colour (well, different shades of grey) to indicate the relative amounts of activity, but I decided to use size as well. So it’s also a bubble chart.

It doesn’t work very elegantly on small screens: the table is clipped horizontally and can be swiped left and right. Ideally the visualisation itself would change to accommodate smaller screens.

Still, I kind of like the end result. Here’s last month’s activity on my site. Here’s the same time period ten years ago. I’ve also added month heatmaps to the monthly archives for my journal, links, and notes. They’re kind of like an expanded view of the sparklines that are shown with each month.

From one year ago, here’s the daily distribution of

And then here’s the the daily distribution of everything in that month all together.

I realise that the data being displayed is probably only of interest to me, but then, that’s one of the perks of having your own website—you can do whatever you feel like.

Checking in at Indie Web Camp Nuremberg

Once I finished my workshop on evaluating technology I stayed in Nuremberg for that weekend’s Indie Web Camp.

IndieWebCamp Nuremberg

Just as with Indie Web Camp Düsseldorf the weekend before, it was a fun two days—one day of discussions, followed by one day of making.

IndieWebCamp Nuremberg IndieWebCamp Nuremberg IndieWebCamp Nuremberg IndieWebCamp Nuremberg

I spent most of the second day playing around with a new service that Aaron created called OwnYourSwarm. It’s very similar to his other service, OwnYourGram. Whereas OwnYourGram is all about posting pictures from Instagram to your own site, OwnYourSwarm is all about posting Swarm check-ins to your own site.

Usually I prefer to publish on my own site and then push copies out to other services like Twitter, Flickr, etc. (POSSE—Publish on Own Site, Syndicate Elsewhere). In the case of Instagram, that’s impossible because of their ludicrously restrictive API, so I have go the other way around (PESOS—Publish Elsewhere, Syndicate to Own Site). When it comes to check-ins, I could do it from my own site, but I’d have to create my own databases of places to check into. I don’t fancy that much (yet) so I’m using OwnYourSwarm to PESOS check-ins.

The great thing about OwnYourSwarm is that I didn’t have to do anything. I already had the building blocks in place.

First of all, I needed some way to authenticate as my website. IndieAuth takes care of all that. All I needed was rel="me" attributes pointing from my website to my profiles on Twitter, Flickr, Github, or any other services that provide OAuth. Then I can piggyback on their authentication flow (this is also how you sign in to the Indie Web wiki).

The other step is more involved. My site needs to provide an API endpoint so that services like OwnYourGram and OwnYourSwarm can post to it. That’s where micropub comes in. You can see the code for my minimal micropub endpoint if you like. If you want to test your own micropub endpoint, check out micropub.rocks—the companion to webmention.rocks.

Anyway, I already had IndieAuth and micropub set up on my site, so all I had to do was log in to OwnYourSwarm and I immediately started to get check-ins posted to my own site. They show up the same as any other note, so I decided to spend my time at Indie Web Camp Nuremberg making them look a bit different. I used Mapbox’s static map API to show an image of the location of the check-in. What’s really nice is that if I post a photo on Swarm, that gets posted to my own site too. I had fun playing around with the display of photo+map on my home page stream. I’ve made a page for keeping track of check-ins too.

All in all, a fun way to spend Indie Web Camp Nuremberg. But when it came time to demo, the one that really impressed me was Amber’s. She worked flat out on her site, getting to the second level on IndieWebify.me …including sending a webmention to my site!

IndieWebCamp Nuremberg

Going offline at Indie Web Camp Düsseldorf

I’ve just come back from a ten-day trip to Germany. The trip kicked off with Indie Web Camp Düsseldorf over the course of a weekend.

IndieWebCamp Düsseldorf 2017

Once again the wonderful people at Sipgate hosted us in their beautiful building, and once again myself and Aaron helped facilitate the two days.

IndieWebCamp Düsseldorf 2017

Saturday was the BarCamp-like discussion day. Plenty of interesting topics were covered. I led a session on service workers, and that’s also what I decided to work on for the second day—that’s when the talking is done and we get down to making.

IndieWebCamp Düsseldorf 2017 IndieWebCamp Düsseldorf 2017 IndieWebCamp Düsseldorf 2017 IndieWebCamp Düsseldorf 2017

I like what Ethan is doing on his offline page. He shows a list of pages that have been cached, but instead of just listing URLs, he shows a title and description for each page.

I’ve already got a separate cache for pages that gets added to as the user browses around my site. I needed to figure out a way to store the metadata for those pages so that I could then display it on the offline page. I came up with a workable solution, and interestingly, it involved no changes to the service worker script at all.

When you visit any blog post, I put metadata about the page into localStorage (after first checking that there’s an active service worker):

if (navigator.serviceWorker && navigator.serviceWorker.controller) {
  window.addEventListener('load', function() {
    var data = {
      "title": "A minority report on artificial intelligence",
      "description": "Revisiting Spielberg’s films after a decade and a half.",
      "published": "May 7th, 2017",
      "timestamp": "1494171049"
    };
    localStorage.setItem(
      window.location.href,
      JSON.stringify(data)
    );
  });
}

In my case, I’m outputting the metadata from the server, but you could just as easily grab some from the DOM like this:

var data = {
  "title": document.querySelector("title").innerText,
  "description": document.querySelector("meta[name='description']").getAttribute("contents")
}

Meanwhile in my service worker, when you visit that same page, it gets added to a cache called “pages”. Both localStorage and the cache API are using URLs as keys. I take advantage of that on my offline page.

The nice thing about writing JavaScript on my offline page is that I know the page will only be seen by modern browsers that support service workers, so I can use all sorts of fancy from ES6, or whatever we’re calling it now.

I start by looping through the keys of the “pages” cache (that’s right—the cache API isn’t just for service workers; you can access it from any script). Then I check to see if there is a corresponding localStorage key with the same string (a URL). If there is, I pull the metadata out of local storage and add it to an array called browsingHistory:

const browsingHistory = [];
caches.open('pages')
.then( cache => {
  cache.keys()
  .then(keys => {
    keys.forEach( request => {
      let data = JSON.parse(localStorage.getItem(request.url));
        if (data) {
          data['url'] = request.url;
          browsingHistory.push(data);
      }
    });

Then I sort the list of pages in reverse chronological order:

browsingHistory.sort( (a,b) => {
  return b.timestamp - a.timestamp;
});

Now I loop through each page in the browsing history list and construct a link to each URL, complete with title and description:

let markup = '';
browsingHistory.forEach( data => {
  markup += `
<h2><a href="${ data.url }">${ data.title }</a></h2>
<p>${ data.description }</p>
<p class="meta">${ data.published }</p>
`;
});

Finally I dump the constructed markup into a waiting div in the page with an ID of “history”:

let container = document.getElementById('history');
container.insertAdjacentHTML('beforeend', markup);

All those steps need to be wrapped inside the then clause attached to caches.open("pages") because the cache API is asynchronous.

There you have it. Now if you’re browsing adactio.com and your network connection drops (or my server goes offline), you can choose from a list of pages you’ve previously visited.

The current situation isn’t ideal though. I’ve got a clean-up operation in my service worker to limit the number of items stored in my “pages” cache. The cache never gets bigger than 35 items. But there’s no corresponding clean-up of metadata stored in localStorage. So there could be a lot more bits of metadata in local storage than there are pages in the cache. It’s not harmful, but it’s a bit wasteful.

I can’t do a clean-up of localStorage from my service worker because service workers can’t access localStorage. There’s a very good reason for that: the localStorage API is synchronous, and everything that happens in a service worker needs to be asynchronous.

Service workers can access indexedDB: it’s asynchronous. I could use indexedDB instead of localStorage, but I’m not a masochist. My best bet would be to use the localForage library, which wraps indexedDB in the simple syntax of localStorage.

Maybe I’ll do that at the next Homebrew Website Club here in Brighton.

Writing on the web

Some people have been putting Paul’s crazy idea into practice.

  • Mike revived his site a while back and he’s been posting gold dust ever since. I enjoy his no-holds-barred perspective on his time in San Francisco.
  • Garrett’s writing goes all the way back to 2005. The cumulative result is two fascinating interweaving narratives—one about his health, another about his business.
  • Charlotte has been documenting her move from Brighton to Sydney. Much as I love her articles about front-end development, I’m liking the slice-of-life updates on life down under even more.
  • Amber has a great way with words. As well as regularly writing on her blog, she’s two-thirds of the way through writing 100 words every day for 100 days.
  • Ethan has been writing about responsive design—of course—but it’s his more personal posts that make me really grateful for his site.
  • Jeffrey and Eric never stopped writing on their own sites. Sure, there’s good stuff on their about web design and development, but it’s the writing about their non-web lives that’s so powerful.

There are more people I could mention …but, to be honest, not that many more. Seems like most people are happy to only publish on Ev’s blog or not at all.

I know not everybody wants to write on the web, and that’s fine. But it makes me sad when people choose not to publish their thoughts because they think no-one will be interested, or that it’s all been said before. I understand where those worries come from, but I believe—no, I know—that they are unfounded.

It’s a world wide web out there. There’s plenty of room for everyone. And I, for one, love reading the words of others.