Tags: ev

2797

sparkline

Sunday, October 13th, 2019

The “P” in Progressive Enhancement stands for “Pragmatism” - Andy Bell

With a Progressive Enhancement mindset, support actually means support. We’re not trying to create an identical experience: we’re creating a viable experience instead.

Also with Progressive Enhancement, it’s incredibly likely that your IE11 user, or your user on a low-powered device, or even your user on a poor connection won’t notice that they’re experiencing a “minor” experience because it’ll just work for them. This is the magic, right there. Everyone’s a winner.

Tuesday, October 8th, 2019

You really don’t need all that JavaScript, I promise

The transcript of a fantastic talk by Stuart. The latter half is a demo of Portals, but in the early part of the talk, he absolutely nails the rise in popularity of complex front-end frameworks:

I think the reason people started inventing client-side frameworks is this: that you lose control when you load another page. You click on a link, you say to the browser: navigate to here. And that’s it; it’s now out of your hands and in the browser’s hands. And then the browser gives you back control when the new page loads.

Sunday, October 6th, 2019

Dark mode

I had a very productive time at Indie Web Camp Amsterdam. The format really lends itself to getting the most of a weekend—one day of discussions followed by one day of hands-on making and doing. You should definitely come along to Indie Web Camp Brighton on October 19th and 20th to experience it for yourself.

By the end of the “doing” day, I had something fun to demo—a dark mode for my website.

Y’know, when I first heard about Apple adding dark mode to their OS—and also to CSS—I thought, “Oh, great, Apple are making shit up again!” But then I realised that, like user style sheets, this is one more reminder to designers and developers that they don’t get the last word—users do.

Applying the dark mode styles is pretty straightforward in theory. You put the styles inside this media query:

@media (prefers-color-scheme: dark) {
...
}

Rather than over-riding every instance of a colour in my style sheet, I decided I’d do a little bit of refactoring first and switch to using CSS custom properties (or variables, if you will).

:root {
  --background-color: #fff;
  --text-color: #333;
  --link-color: #b52;
}
body {
  background-color: var(--background-color);
  color: var(--text-color);
}
a {
  color: var(--link-color);
}

Then I can over-ride the custom properties without having to touch the already-declared styles:

@media (prefers-color-scheme: dark) {
  :root {
    --background-color: #111416
    --text-color: #ccc;
    --link-color: #f96;
  }
}

All in all, I have about a dozen custom properties for colours—variations for text, backgrounds, and interface elements like links and buttons.

By using custom properties and the prefers-color-scheme media query, I was 90% of the way there. But the devil is in the details.

I have SVGs of sparklines on my homepage. The SVG has a hard-coded colour value in the stroke attribute of the path element that draws the sparkline. Fortunately, this can be over-ridden in the style sheet:

svg.activity-sparkline path {
  stroke: var(--text-color);
}

The real challenge came with the images I use in the headers of my pages. They’re JPEGs with white corners on one side and white gradients on the other.

header images

I could make them PNGs to get transparency, but the file size would shoot up—they’re photographic images (with a little bit of scan-line treatment) so JPEGs (or WEBPs) are the better format. Then I realised I could use CSS to recreate the two effects:

  1. For the cut-out triangle in the top corner, there’s clip-path.
  2. For the gradient, there’s …gradients!
background-image: linear-gradient(
  to right,
  transparent 50%,
  var(—background-color) 100%
);

Oh, and I noticed that when I applied the clip-path for the corners, it had no effect in Safari. It turns out that after half a decade of support, it still only exists with -webkit prefix. That’s just ridiculous. At this point we should be burning vendor prefixes with fire. I can’t believe that Apple still ships standardised CSS properties that only work with a prefix.

In order to apply the CSS clip-path and gradient, I needed to save out the images again, this time without the effects baked in. I found the original Photoshop file I used to export the images. But I don’t have a copy of Photoshop any more. I haven’t had a copy of Photoshop since Adobe switched to their Mafia model of pricing. A quick bit of searching turned up Photopea, which is pretty much an entire recreation of Photoshop in the browser. I was able to open my old PSD file and re-export my images.

LEGO clone trooper Brighton bandstand Scaffolding Tokyo Florence

Let’s just take a moment here to pause and reflect on the fact that we can now use CSS to create all sorts of effects that previously required a graphic design tool like Photoshop. I could probably do those raster scan lines with CSS if I were smart enough.

dark mode

This is what I demo’d at the end of Indie Web Camp Amsterdam, and I was pleased with the results. But fate had an extra bit of good timing in store for me.

The very next day at the View Source conference, Melanie Richards gave a fantastic talk called The Tailored Web: Effectively Honoring Visual Preferences (seriously, conference organisers, you want this talk on your line-up). It was packed with great insights and advice on impementing dark mode, like this little gem for adjusting images:

@media (prefers-color-scheme: dark) {
  img {
    filter: brightness(.8) contrast(1.2);
  }
}

Melanie also pointed out that you can indicate the presence of dark mode styles to browsers, although the mechanism is yet to shake out. You can do it in CSS:

:root {
  color-scheme: light dark;
}

But you can also do it in HTML:

<meta name="supported-color-schemes" content="light dark">

That allows browsers to swap out replaced content; interface elements like form fields and dropdowns.

Oh, and one other addition I added after the fact was swapping out map imagery by using the picture element to point to darker map tiles:

<picture>
<source media="prefers-color-scheme: dark" srcset="https://api.mapbox.com/styles/v1/mapbox/dark-v10/static...">
<img src="https://api.mapbox.com/styles/v1/mapbox/outdoors-v10/static..." alt="map">
</picture>

light map dark map

So now I’ve got a dark mode for my website. Admittedly, it’s for just one of the eight style sheets. I’ve decided that, while I’ll update my default styles at every opportunity, I’m going to preservethe other skins as they are, like the historical museum pieces they are.

If you’re on the latest version of iOS, go ahead and toggle the light and dark options in your system preferences to flip between this site’s colour schemes.

How to be a more productive developer | Go Make Things

Like Michael Pollan’s food rules, but for JavaScript:

  1. Plan your scripts out on paper.
  2. Stop obsessing over tools.
  3. Focus on solving problems.
  4. Maintain a library of snippets that you can reuse.

Saturday, October 5th, 2019

do you know your tags?

Test your knowledge of the original version of HTML—how many elements can you name?

Friday, October 4th, 2019

Designing a focus style | Zell Liew

A deep dive info focus styles with this conclusion:

The default focus ring works. There are problems with it, but it can be good enough, especially if you can’t dedicate time and energy to create a custom focus ring.

Why Progressive Web Apps Are The Future of Mobile Web [2019 Research]

PWAs just work better than your typical mobile site. Period.

But bear in mind:

Maybe simply because the “A” in PWA stands for “app,” too much discussion around PWAs focuses on comparing and contrasting to native mobile applications. We believe this comparison (and the accompanying discussion) is misguided.

Thursday, October 3rd, 2019

Travel talk

It’s been a busy two weeks of travelling and speaking. Last week I spoke at Finch Conf in Edinburgh, Code Motion in Madrid, and Generate CSS in London. This week I was at Indie Web Camp, View Source, and Fronteers, all in Amsterdam.

The Edinburgh-Madrid-London whirlwind wasn’t ideal. I gave the opening talk at Finch Conf, then immediately jumped in a taxi to get to the airport to fly to Madrid, so I missed all the excellent talks. I had FOMO for a conference I actually spoke at.

I did get to spend some time at Code Motion in Madrid, but that was a waste of time. It was one of those multi-track events where the trade show floor is prioritised over the talks (and the speakers don’t get paid). I gave my talk to a mostly empty room—the classic multi-track experience. On the plus side, I had a wonderful time with Jessica exploring Madrid’s many tapas delights. The food and drink made up for the sub-par conference.

I flew back from Madrid to the UK, and immediately went straight to London to deliver the closing talk of Generate CSS. So once again, I didn’t get to see any of the other talks. That’s a real shame—it sounds like they were all excellent.

The day after Generate though, I took the Eurostar to Amsterdam. That’s where I’ve been ever since. There were just as many events as in the previous week, but because they were all in Amsterdam, I could savour them properly, instead of spending half my time travelling.

Indie Web Camp Amsterdam was excellent, although I missed out on the afternoon discussions on the first day because I popped over to the Mozilla Tech Speakers event happening at the same time. I was there to offer feedback on lightning talks. I really, really enjoyed it.

I’d really like to do more of this kind of thing. There aren’t many activities I feel qualified to give advice on, but public speaking is an exception. I’ve got plenty of experience that I’m eager to share with up-and-coming speakers. Also, I got to see some really great lightning talks!

Then it was time for View Source. There was a mix of talks, panels, and breakout conversation corners. I saw some fantastic talks by people I hadn’t seen speak before: Melanie Richards, Ali Spittal, Sharell Bryant, and Tejas Kumar. I gave the closing keynote, which was warmly received—that’s always very gratifying.

After one day of rest, it was time for Fronteers. This was where myself and Remy gave the joint talk we’ve been working on:

Neither of us is under any illusions about the nature of a joint talk. It’s not half as much work; it’s more like twice the work. We’ve both seen enough uneven joint presentations to know what we want to avoid.

I’m happy to say that it went off without a hitch. Remy definitely had the tougher task—he did a live demo. Needless to say, he did it flawlessly. It’s been a real treat working with Remy on this. Don’t tell him I said this, but he’s kind of a web hero of mine, so this was a real honour and a privilege for me.

I’ve got some more speaking engagements ahead of me. Most of them are in Europe so I’m going to do my utmost to travel to them by train. Flying is usually more convenient but it’s terrible for my carbon footprint. I’m feeling pretty guilty about that Madrid trip; I need to make ammends.

I’ll be travelling to France next week for Paris Web. Taking the Eurostar is a no-brainer for that one. Straight after that Jessica and I will be going to Frankfurt for the book fair. Taking the train from Paris to Frankfurt will be nice and straightforward.

I’ll be back in Brighton for Indie Web Camp on the weekend of October 19th and 20th—you should come!—and then I’ll be heading off to Antwerp for Full Stack Fest. Anywhere in Belgium is easily reachable by train so that’ll be another Eurostar journey.

After that, it gets a little trickier. I’ll be going to Berlin for Beyond Tellerrand but I’m not sure I can make it work by train. Same goes for Web Clerks in Vienna. Cities that far east are tough to get to by train in a reasonable amount of time (although I realise that, compared to many others, I have the luxury of spending time travelling by train).

Then there are the places that I can only get to by plane. There’s the United States. I’ll be speaking at An Event Apart in San Francisco in December. A flight is unavoidable. Last time we went to the States, Jessica and I travelled by ocean liner. But that isn’t any better for the environment, given the low-grade fuel burned by ships.

And then there’s Ireland. I make trips back there to see my mother, but there’s no alternative to flying or taking a ferry—neither are ideal for the environment. At least I can offset the carbon from my flights; the travel equivalent to putting coins in the swear jar.

Don’t get me wrong—I’m not moaning about the amount of travel involved in going to conferences and workshops. It’s fantastic that I get to go to new and interesting places. That’s something I hope I never take for granted. But I can’t ignore the environmental damage I’m doing. I’ll be making more of an effort to travel by train to Europe’s many excellent web events. While I’m at it, I can ask Paul for his trainspotter expertise.

A Modern CSS Reset - Andy Bell

Some very smart ideas in here for resetting default browser styles, like only resetting lists that have classes applied to them:

ul[class],
ol[class] {
  padding: 0;
}

I select only lists that do have a class attribute because if a plain ol’ <ul> or <ol> gets used, I want it to look like a list. A lot of resets, including my previous ones, aggressively remove that.

Blog service workers and the chicken and the egg

This is a great little technique from Remy: when a service worker is being installed, you make sure that the page(s) the user is first visiting get added to a cache.

Wednesday, October 2nd, 2019

The perfect responsive menu (2019) | Polypane responsive browser

I don’t know about “perfect” but this pretty much matches how I go about implementing responsive navigation (but only if there are too many links to show—visible navigation is almost always preferable).

What Makes a Mid-Level Developer? | Amber’s Website

I love the way that Amber is documenting her journey—I think this is so useful for others making the progression from junior to mid-level developer.

Friday, September 27th, 2019

The Octopus: An Alien Among Us | Literary Hub

An excerpt from the book Rethinking Consciousness by Michael S. A. Graziano, which looks like an interesting companion piece to Peter Godfrey-Smith’s excellent Other Minds.

Also, can I just say how nice this reading experience is—the typography, the arresting image …I like it.

Saturday, September 21st, 2019

Going offline with microformats

For the offline page on my website, I’ve been using a mixture of the Cache API and the localStorage API. My service worker script uses the Cache API to store copies of pages for offline retrieval. But I used the localStorage API to store metadata about the page—title, description, and so on. Then, my offline page would rifle through the pages stored in a cache, and retreive the corresponding metadata from localStorage.

It all worked fine, but as soon as I read Remy’s post about the forehead-slappingly brilliant technique he’s using, I knew I’d be switching my code over. Instead of using localStorage—or any other browser API—to store and retrieve metadata, he uses the pages themselves! Using the Cache API, you can examine the contents of the pages you’ve stored, and get at whatever information you need:

I realised I didn’t need to store anything. HTML is the API.

Refactoring the code for my offline page felt good for a couple of reasons. First of all, I was able to remove a dependency—localStorage—and simplify the JavaScript. That always feels good. But the other reason for the warm fuzzies is that I was able to use data instead of metadata.

Many years ago, Cory Doctorow wrote a piece called Metacrap. In it, he enumerates the many issues with metadata—data about data. The source of many problems is when the metadata is stored separately from the data it describes. The data may get updated, without a corresponding update happening to the metadata. Metadata tends to rot because it’s invisible—out of sight and out of mind.

In fact, that’s always been at the heart of one of the core principles behind microformats. Instead of duplicating information—once as data and again as metadata—repurpose the visible data; mark it up so its meta-information is directly attached to the information itself.

So if you have a person’s contact details on a web page, rather than repeating that information somewhere else—in the head of the document, say—you could instead attach some kind of marker to indicate which bits of the visible information are contact details. In the case of microformats, that’s done with class attributes. You can mark up a page that already has your contact information with classes from the h-card microformat.

Here on my website, I’ve marked up my blog posts, articles, and links using the h-entry microformat. These classes explicitly mark up the content to say “this is the title”, “this is the content”, and so on. This makes it easier for other people to repurpose my content. If, for example, I reply to a post on someone else’s website, and ping them with a webmention, they can retrieve my post and know which bit is the title, which bit is the content, and so on.

When I read Remy’s post about using the Cache API to retrieve information directly from cached pages, I knew I wouldn’t have to do much work. Because all of my posts are already marked up with h-entry classes, I could use those hooks to create a nice offline page.

The markup for my offline page looks like this:

<h1>Offline</h1>
<p>Sorry. It looks like the network connection isn’t working right now.</p>
<div id="history">
</div>

I’ll populate that “history” div with information from a cache called “pages” that I’ve created using the Cache API in my service worker.

I’m going to use async/await to do this because there are lots of steps that rely on the completion of the step before. “Open this cache, then get the keys of that cache, then loop through the pages, then…” All of those thens would lead to some serious indentation without async/await.

All async functions have to have a name—no anonymous async functions allowed. I’m calling this one listPages, just like Remy is doing. I’m making the listPages function execute immediately:

(async function listPages() {
...
})();

Now for the code to go inside that immediately-invoked function.

I create an array called browsingHistory that I’ll populate with the data I’ll use for that “history” div.

const browsingHistory = [];

I’m going to be parsing web pages later on, so I’m going to need a DOM parser. I give it the imaginative name of …parser.

const parser = new DOMParser();

Time to open up my “pages” cache. This is the first await statement. When the cache is opened, this promise will resolve and I’ll have access to this cache using the variable …cache (again with the imaginative naming).

const cache = await caches.open('pages');

Now I get the keys of the cache—that’s a list of all the page requests in there. This is the second await. Once the keys have been retrieved, I’ll have a variable that’s got a list of all those pages. You’ll never guess what I’m calling the variable that stores the keys of the cache. That’s right …keys!

const keys = await cache.keys();

Time to get looping. I’m getting each request in the list of keys using a for/of loop:

for (const request of keys) {
...
}

Inside the loop, I pull the page out of the cache using the match() method of the Cache API. I’ll store what I get back in a variable called response. As with everything involving the Cache API, this is asynchronous so I need to use the await keyword here.

const response = await cache.match(request);

I’m not interested in the headers of the response. I’m specifically looking for the HTML itself. I can get at that using the text() method. Again, it’s asynchronous and I want this promise to resolve before doing anything else, so I use the await keyword. When the promise resolves, I’ll have a variable called html that contains the body of the response.

const html = await response.text();

Now I can use that DOM parser I created earlier. I’ve got a string of text in the html variable. I can generate a Document Object Model from that string using the parseFromString() method. This isn’t asynchronous so there’s no need for the await keyword.

const dom = parser.parseFromString(html, 'text/html');

Now I’ve got a DOM, which I have creatively stored in a variable called …dom.

I can poke at it using DOM methods like querySelector. I can test to see if this particular page has an h-entry on it by looking for an element with a class attribute containing the value “h-entry”:

if (dom.querySelector('.h-entry h1.p-name') {
...
}

In this particular case, I’m also checking to see if the h1 element of the page is the title of the h-entry. That’s so that index pages (like my home page) won’t get past this if statement.

Inside the if statement, I’m going to store the data I retrieve from the DOM. I’ll save the data into an object called …data!

const data = new Object;

Well, the first piece of data isn’t actually in the markup: it’s the URL of the page. I can get that from the request variable in my for loop.

data.url = request.url;

I’m going to store the timestamp for this h-entry. I can get that from the datetime attribute of the time element marked up with a class of dt-published.

data.timestamp = new Date(dom.querySelector('.h-entry .dt-published').getAttribute('datetime'));

While I’m at it, I’m going to grab the human-readable date from the innerText property of that same time.dt-published element.

data.published = dom.querySelector('.h-entry .dt-published').innerText;

The title of the h-entry is in the innerText of the element with a class of p-name.

data.title = dom.querySelector('.h-entry .p-name').innerText;

At this point, I am actually going to use some metacrap instead of the visible h-entry content. I don’t output a description of the post anywhere in the body of the page, but I do put it in the head in a meta element. I’ll grab that now.

data.description = dom.querySelector('meta[name="description"]').getAttribute('content');

Alright. I’ve got a URL, a timestamp, a publication date, a title, and a description, all retrieved from the HTML. I’ll stick all of that data into my browsingHistory array.

browsingHistory.push(data);

My if statement and my for/in loop are finished at this point. Here’s how the whole loop looks:

for (const request of keys) {
  const response = await cache.match(request);
  const html = await response.text();
  const dom = parser.parseFromString(html, 'text/html');
  if (dom.querySelector('.h-entry h1.p-name')) {
    const data = new Object;
    data.url = request.url;
    data.timestamp = new Date(dom.querySelector('.h-entry .dt-published').getAttribute('datetime'));
    data.published = dom.querySelector('.h-entry .dt-published').innerText;
    data.title = dom.querySelector('.h-entry .p-name').innerText;
    data.description = dom.querySelector('meta[name="description"]').getAttribute('content');
    browsingHistory.push(data);
  }
}

That’s the data collection part of the code. Now I’m going to take all that yummy information an output it onto the page.

First of all, I want to make sure that the browsingHistory array isn’t empty. There’s no point going any further if it is.

if (browsingHistory.length) {
...
}

Within this if statement, I can do what I want with the data I’ve put into the browsingHistory array.

I’m going to arrange the data by date published. I’m not sure if this is the right thing to do. Maybe it makes more sense to show the pages in the order in which you last visited them. I may end up removing this at some point, but for now, here’s how I sort the browsingHistory array according to the timestamp property of each item within it:

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

Now I’m going to concatenate some strings. This is the string of HTML text that will eventually be put into the “history” div. I’m storing the markup in a string called …markup (my imagination knows no bounds).

let markup = '<p>But you still have something to read:</p>';

I’m going to add a chunk of markup for each item of data.

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

With my markup assembled, I can now insert it into the “history” part of my offline page. I’m using the handy insertAdjacentHTML() method to do this.

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

Here’s what my finished JavaScript looks like:

<script>
(async function listPages() {
  const browsingHistory = [];
  const parser = new DOMParser();
  const cache = await caches.open('pages');
  const keys = await cache.keys();
  for (const request of keys) {
    const response = await cache.match(request);
    const html = await response.text();
    const dom = parser.parseFromString(html, 'text/html');
    if (dom.querySelector('.h-entry h1.p-name')) {
      const data = new Object;
      data.url = request.url;
      data.timestamp = new Date(dom.querySelector('.h-entry .dt-published').getAttribute('datetime'));
      data.published = dom.querySelector('.h-entry .dt-published').innerText;
      data.title = dom.querySelector('.h-entry .p-name').innerText;
      data.description = dom.querySelector('meta[name="description"]').getAttribute('content');
      browsingHistory.push(data);
    }
  }
  if (browsingHistory.length) {
    browsingHistory.sort( (a,b) => {
      return b.timestamp - a.timestamp;
    });
    let markup = '<p>But you still have something to read:</p>';
    browsingHistory.forEach( data => {
      markup += `
<h2><a href="${ data.url }">${ data.title }</a></h2>
<p>${ data.description }</p>
<p class="meta">${ data.published }</p>
`;
    });
    document.getElementById('history').insertAdjacentHTML('beforeend', markup);
  }
})();
</script>

I’m pretty happy with that. It’s not too long but it’s still quite readable (I hope). It shows that the Cache API and the h-entry microformat are a match made in heaven.

If you’ve got an offline strategy for your website, and you’re using h-entry to mark up your content, feel free to use that code.

If you don’t have an offline strategy for your website, there’s a book for that.

Friday, September 20th, 2019

Frank Chimero · Tweenage Computing

Frank yearns for just-in-time computing:

With each year that goes by, it feels like less and less is happening on the device itself. And the longer our work maintains its current form (writing documents, updating spreadsheets, using web apps, responding to emails, monitoring chat, drawing rectangles), the more unnecessary high-end computing seems. Who needs multiple computers when I only need half of one?

Thursday, September 19th, 2019

An HTML attribute potentially worth $4.4M to Chipotle - Cloud Four

When I liveblogged Jason’s talk at An Event Apart in Chicago, I included this bit of reporting:

Jason proceeds to relate a long and involved story about buying burritos online from Chipotle.

Well, here is that story. It’s a good one, with some practical takeaways (if you’ll pardon the pun):

  1. Use HTML5 input features
  2. Support autofill
  3. Make autofill part of your test plans

Wednesday, September 18th, 2019

Keeping it simple with CSS that scales - Andy Bell

The transcript of Andy’s talk from this year’s State Of The Browser conference.

I don’t think using scale as an excuse for over-engineering stuff—especially CSS—is acceptable, even for huge teams that work on huge products.

Tuesday, September 17th, 2019

NoJS Side-by-Side

Drag this to your browser’s bookmark bar now!

Such a useful quick check for resilience—this bookmarklet shows you a side-by-side comparison of a site with JavaScript enabled and disabled.

Monday, September 16th, 2019

The Book | The Lean Web

This is such a great little web book from Chris Ferdinandi that you can read online for free.

  1. Intro
  2. Modern Best Practices
  3. How did we get here?
  4. Lean Web Principles
  5. What now?

Friday, September 13th, 2019

5G Will Definitely Make the Web Slower, Maybe | Filament Group, Inc.

The Jevons Paradox in action:

Faster networks should fix our performance problems, but so far, they have had an interesting if unintentional impact on the web. This is because historically, faster network speed has enabled developers to deliver more code to users—in particular, more JavaScript code.

And because it’s JavaScript we’re talking about:

Even if folks are on a new fast network, they’re very likely choking on the code we’re sending, rendering the potential speed improvements of 5G moot.

The longer I spend in this field, the more convinced I am that web performance is not a technical problem; it’s a people problem.