So, why would you want to use a service worker? Here are some cool things you can do with it.
Chris lists some of the ways a service worker can enhance user experience.
So, why would you want to use a service worker? Here are some cool things you can do with it.
Chris lists some of the ways a service worker can enhance user experience.
What web development can learn from the Nintendo Game and Watch.
The Web now consists of an ever-growing number of different frameworks, methodologies, screen sizes, devices, browsers, and connection speeds. “Lateral thinking with withered technology” – progressively enhanced – might actually be an ideal philosophy for building accessible, performant, resilient, and original experiences for a wide audience of users on the Web.
A heartfelt look at progressive enhancement:
Some look at progressive enhancement like a thing from the past of which the old guard just can’t let go. But to me, progressive enhancement is the future of the Web. It is the basis for building resilient, performant, interoperable, secure, usable, accessible, and thus inclusive experiences. Not only for the Web of today but for the ever-growing complexity of an ever-changing and ever-evolving Web.
This is great! Ideas for allowing more styling of form controls. I agree with the goals 100% and I like the look of the proposed solutions too.
The team behind this are looking for feedback so be sure to share your thoughts (I’ll probably formulate mine into a blog post).
A Chrome-only API for adding offline content to an index that can be exposed in Android’s “downloads” list. It just shipped in the lastest version of Chrome.
I’m not a fan of browser-specific non-standards but you can treat this as an enhancement—implementing it doesn’t harm non-supporting browsers and you can use feature detection to test for it.
How do we tell our visitors our sites work offline? How do we tell our visitors that they don’t need an app because it’s no more capable than the URL they’re on right now?
Remy expands on his call for ideas on branding websites that work offline with a universal symbol, along the lines of what we had with RSS.
What I’d personally like to see as an outcome: some simple iconography that I can use on my own site and other projects that can offer ambient badging to reassure my visitor that the URL they’re visiting will work offline.
I’ve always been a fan of using the first few milliseconds of a user’s attention getting what I have to share with them — in front of them. Then worrying setting up the interaction layer while the user can start processing what they’re seeing.
The pushback I get usually takes the form of “Well, that approach is fine for websites, but it wouldn’t work something like Gmail.”
It’s always Gmail. Which is odd. Because if you really wanted to flummox me with a product or service that defies progressive enhancement, I’d have a hard time with something like, say, a game (although it would be pretty cool to build a text adventure that’s progressively enhanced into a first-person shooter). But an email client? That would work.
Identify core functionality.
Read emails. Write emails.
Make that functionality available using the simplest possible technology.
HTML for showing a list of emails, HTML for displaying the contents of the HTML, HTML for the form you write the response in.
Now add all the enhancements that improve the experience—keyboard shortcuts; Ajax instead of full-page refreshes; local storage, all that stuff.
Progressive enhancement isn’t about making a choice between using simpler more robust technologies or using more advanced features; it’s about using simpler more robust technologies and then using more advanced features. Have your cake and eat it.
Fortunately I no longer need to run this thought experiment to imagine what it would be like if something like Gmail were built with a progressive enhancement approach. That’s what HEY is.
HEY’s UI is 100% HTML over the wire. We render plain-old HTML pages on the server and send them to your browser encoded as text/html. No JSON APIs, no GraphQL, no React—just form submissions and links.
If you think that sounds like the web of 25 years ago, you’re right! Except the HEY front-end stack progressively enhances the “classic web” to work like the “2020 web,” with all the fidelity you’d expect from a well-built SPA.
See? It’s not either resilient or modern—it’s resilient and modern. Have your cake and eat it.
And yet this supremely sensible approach is not considered “modern” web development:
The architecture astronauts who, for the past decade, have been selling us on the necessity of React, Redux, and megabytes of JS, cannot comprehend the possibility of building an email app in 2020 with server-rendered HTML.
HEY isn’t perfect by any means—they’ve got a lot of work to do on their accessibility. But it’s good to have a nice short answer to the question “But what about something like Gmail?”
When Ethan Marcotte demonstrated the power of responsive design, it was met with resistance. “Sure, a responsive design might work for a simple personal site but there’s no way it could scale to a large complex project.”
Then the Boston Globe launched its responsive site. Microsoft made their homepage responsive. The floodgates opened again.
It’s a similar story today. “Sure, progressive enhancement might work for a simple personal site, but there’s no way it could scale to a large complex project.”
The floodgates are ready to open. We just need you to create the poster child for resilient web design.
It looks like HEY might be that poster child.
I have to wonder if its coincidence or connected that this is a service that’s also tackling ethical issues like tracking? Their focus is very much on people above technology. They’ve taken a human-centric approach to their product and a human-centric approach to web development …because ultimately, that’s what progressive enhancement is.
This is an interesting push by Remy to try to figure out a way we can collectively indicate to users that a site works offline.
Well, seeing as browsers have completely dropped the ball on any kind of ambient badging, it’s fair enough that we take matters into our own hands.
I feel for BaseCamp, I do. But give up on the native app path. Make sure your existing web interface is a good progressive web app and you can end-run around Apple.
I really, really like Andy’s approach here:
The focus of the methodology is utilising the power of CSS and the web platform as a whole, with some added controls and structures that help to keep things a bit more maintainable and predictable. The end-goal is shipping as little CSS as possible—leaning heavily into progressive enhancement and modern techniques.
If you use the cascade for everything, you’re going to run into trouble. But equally, micro-managing styles on every element will also get you into trouble. I think Andy’s found a really great sweet spot here that gets the balance just right.
CUBE CSS in essence, is a progressive enhancement approach, vs a fight against the grain of CSS or a pixel-pushing your project to within an inch of its life approach.
Yes! It feels very “webby” to me.
Progressive disclosure interface patterns categorised and evaluated:
I really like the hypertext history invoked in this article.
The piece finishes with a great note on the MacNamara fallacy:
Everyone thinks metrics let us measure results. But, actually, they don’t. They measure only what they are measuring. Engagement, for example, is not something that can be measured, so we use an analogue for it. Time on page. Or clicks.
We often end up measuring what is quick, cheap, and easy to measure. Therefore, few organizations regularly conduct usability testing or customer-satisfaction surveys, but lots use analytics.
Even today, organizations often use clicks as a measure of engagement. So, all too often, they design user interfaces to generate clicks, so the system can measure them.
Some great practical examples of progressive enhancement on one website:
pictureelement to provide
webpimages in HTML.
All of those enhancements work great in modern browsers, but the underlying functionality is still available to a browser like Opera Mini on a feature phone.
This isn’t the time to get precious about your favourite design and development tools. Use progressive enhancement as your philosophy. Your service might have to be accessed on old devices in hospitals with outdated tech or unsupported operating systems. HTML+CSS is your best bet to ensure that the service can be accessed in unlikely scenarios you’ve never even considered. Do you want to take that risk at a time like this? Nope, me neither.
Save the React squabbles for another time. Make it accessible and robust from day one.
Great typography on the web should be designed in layers. The web is an imperfect medium, consumed by countless different devices over untold numbers of network connections—each with their own capabilities, limitations, and peculiarities. To think that you can create one solution that will look and work the same everywhere is a fantasy. To make this more than just one nice book website, the whole project and process needs to embrace this reality.
I really enjoyed having a chat with Ed and Tom on their podcast. It’s aimed at people making a career shift into web development, but that didn’t stop me banging on about my usual hobby horses: progressive enhancement, resilient web design, and all that jazz.
I was supposed to be in Plymouth yesterday, giving the opening talk at this year’s Future Sync conference. Obviously, that train journey never happened, but the conference did.
The organisers gave us speakers the option of pre-recording our talks, which I jumped on. It meant that I wouldn’t be reliant on a good internet connection at the crucial moment. It also meant that I was available to provide additional context—mostly in the form of a deluge of hyperlinks—in the chat window that accompanied the livestream.
The whole thing went very smoothly indeed. Here’s the video of my talk. It was The Layers Of The Web, which I’ve only given once before, at Beyond Tellerrand Berlin last November (in the Before Times).
As well as answering questions in the chat room, people were also asking questions in Sli.do. But rather than answering those questions there, I was supposed to respond in a social medium of my choosing. I chose my own website, with copies syndicated to Twitter.
Here are those questions and answers…
The first few questions were about last years’s CERN project, which opens the talk:
It was an unbelievable privilege! I was so excited the whole time—I still can hardly believe it really happened!
Later in the presentation, I talked about service workers and progressive web apps. I got a technical question about that:
Great question! Yes, there are limits, but we’re generally talking megabytes here. It varies from browser to browser and depends on the available space on the device.
But files stored using the Cache API are less likely to be deleted than files stored in the browser cache.
More worrying is the announcement from Apple to only store files for a week of browser use:
Finally, there was a question about the over-arching theme of the talk…
Yes! …And that’s why I never once used the phrase “progressive enhancement” in my talk. 🙂
There’s a lot of misunderstanding of the term. Rather than correct it, I now avoid it:
Instead of using the phrase “progressive enhancement”, I now talk about the benefits and effects of the technique: resilience, universality, etc.
The cloud gives us collaboration, but old-fashioned apps give us ownership. Can’t we have the best of both worlds?
We would like both the convenient cross-device access and real-time collaboration provided by cloud apps, and also the personal ownership of your own data embodied by “old-fashioned” software.
This is a very in-depth look at the mindset and the challenges involved in building truly local-first software—something that Tantek has also been thinking about.
Apple aren’t the best at developer relations. But, bad as their communications can be, I’m willing to cut them some slack. After all, they’re not used to talking with the developer community.
John Wilander wrote a blog post that starts with some excellent news: Full Third-Party Cookie Blocking and More. Safari is catching up to Firefox and disabling third-party cookies by default. Wonderful! I’ve had third-party cookies disabled for a few years now, and while something occassionally breaks, it’s honestly a pretty great experience all around. Denying companies the ability to track users across sites is A Good Thing.
In the same blog post, John said that client-side cookies will be capped to a seven-day lifespan, as previously announced. Just to be clear, this only applies to client-side cookies. If you’re setting a cookie on the server, using PHP or some other server-side language, it won’t be affected. So persistent logins are still doable.
Then, in an audacious example of burying the lede, towards the end of the blog post, John announces that a whole bunch of other client-side storage technologies will also be capped to seven days. Most of the technologies are APIs that, like cookies, can be used to store data: Indexed DB, Local Storage, and Session Storage (though there’s no mention of the Cache API). At the bottom of the list is this:
Service Worker registrations
Okay, let’s clear up a few things here (because they have been so poorly communicated in the blog post)…
The seven day timer refers to seven days of Safari usage, not seven calendar days (although, given how often most people use their phones, the two are probably interchangable). So if someone returns to your site within a seven day period of using Safari, the timer resets to zero, and your service worker gets a stay of execution. Lucky you.
This only applies to Safari. So if your site has been added to the home screen and your web app manifest has a value for the “display” property like “standalone” or “full screen”, the seven day timer doesn’t apply.
That piece of information was missing from the initial blog post. Since the blog post was updated to include this clarification, some people have taken this to mean that progressive web apps aren’t affected by the upcoming change. Not true. Only progressive web apps that have been added to the home screen (and that have an appropriate “display” value) will be spared. That’s a vanishingly small percentage of progressive web apps, especially on iOS. To add a site to the home screen on iOS, you need to dig and scroll through the share menu to find the right option. And you need to do this unprompted. There is no ambient badging in Safari to indicate that a site is installable. Chrome’s install banner isn’t perfect, but it’s better than nothing.
Just a reminder: a progressive web app is a website that
Adding to the home screen is something you can do with a progressive web app (or any other website). It is not what defines progressive web apps.
In any case, this move to delete service workers after seven days of using Safari is very odd, and I’m struggling to find the connection to the rest of the blog post, which is about technologies that can store data.
As I understand it, with the crackdown on setting third-party cookies, trackers are moving to first-party technologies. So whereas in the past, a tracking company could tell its customers “Add this
script element to your pages”, now they have to say “Add this
The best explanation I can come up with for this move by Apple is that it feels like the neatest solution. That’s neat as in tidy, not as in nifty. It is definitely not a nifty solution.
If some technologies set by a specific domain are being purged after seven days, then the tidy thing to do is purge all technologies from that domain. Service workers are getting included in that dragnet.
Now, to be fair, browsers and operating systems are free to clean up storage space as they see fit. Caches, Local Storage, Indexed DB—all of those are subject to eventually getting cleaned up.
So I was curious. Wanting to give Apple the benefit of the doubt, I set about trying to find out how long service worker registrations currently last before getting deleted. Maybe this announcement of a seven day time limit would turn out to be not such a big change from current behaviour. Maybe currently service workers last for 90 days, or 60, or just 30.
There was no time limit previously.
This is not a minor change. This is a crippling attack on service workers, a technology specifically designed to improve the user experience for return visits, whether it’s through improved performance or offline access.
I wouldn’t be so stunned had this announcement come with an accompanying feature that would allow Safari users to know when a website is a progressive web app that can be added to the home screen. But Safari continues to ignore the existence of progressive web apps. And now it will actively discourage people from using service workers.
If you’d like to give feedback on this ludicrous development, you can file a bug (down in the cellar in the bottom of a locked filing cabinet stuck in a disused lavatory with a sign on the door saying “Beware of the Leopard”).
No doubt there will still be plenty of Apple apologists telling us why it’s good that Safari has wished service workers into the cornfield. But make no mistake. This is a terrible move by Apple.
I will say this though: given The Situation we’re all living in right now, some good ol’ fashioned Hot Drama by a browser vendor behaving badly feels almost comforting.