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Monday, September 23rd, 2019

Checked in at Que Trabaje Rita!. Cerveza — with Jessica map

Checked in at Que Trabaje Rita!. Cerveza — with Jessica

Sunday, September 22nd, 2019

Thistle and crag.

Thistle and crag.

Checked in at The Waverley. Scottish session — with Jessica map

Checked in at The Waverley. Scottish session — with Jessica

There’s so much history in Edinburgh…

There’s so much history in Edinburgh…

Picture 1 Picture 2

Out’n’about in Edinburgh.

map

Checked in at Sandy Bell’s. Listening to tunes — with Jessica

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.

Reading The Science of Storytelling by Will Storr.

Thinking vs Choosing – The Haystack

There seems to be a tendency to repurpose existing solutions to other people’s problems. I propose that this is the main cause of the design sameness that we encounter on the web (and in apps) today. In our (un)conscious attempts to reduce the effort needed to do our work, we’ve become experts in choosing rather than in thinking.

A very thoughtful piece from Stephen.

When we use existing solutions or patterns, we use a different kind of thinking. Our focus is on finding which pattern will work for us. Too quickly, we turn our attention away from closely examining the problem.

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

At Dynamicland, The Building Is The Computer — Carl Tashian

A look at the ubiquitous computing work that Bret Victor has been doing over the past few years at Dynamicland.

A bit of a tangent, but I love this description of reading maps:

Map reading is a complex and uniquely human skill, not at all obvious to a young child. You float out of your body and into the sky, leaving behind the point of view you’ve been accustomed to all your life. Your imagination turns squiggly blue lines and green shading into creeks, mountains, and forests seen from above. Bringing it all together in your mind’s eye, you can picture the surroundings.

Wednesday, September 18th, 2019

Checked in at Jolly Brewer. Fiddles at the ready 🎻 — with Jessica map

Checked in at Jolly Brewer. Fiddles at the ready 🎻 — with Jessica

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.

Picture 1 Picture 2

Reading on the beach. 📖 🌊

A love letter to my website - DESK Magazine

We choose whether our work stays alive on the internet. As long as we keep our hosting active, our site remains online. Compare that to social media platforms that go public one day and bankrupt the next, shutting down their app and your content along with it.

Your content is yours.

But the real truth is that as long as we’re putting our work in someone else’s hands, we forfeit our ownership over it. When we create our own website, we own it – at least to the extent that the internet, beautiful in its amorphous existence, can be owned.

The Appification of Everything & Why it Needs to End

When your only tool seems like a smartphone, everything looks like an app.

Amber writes on Ev’s blog about products that deliberately choose to be dependent on smartphone connectivity:

We read service outage stories like these seemingly every week, and have become numb to the fundamental reality: The idea of placing the safety of yourself, your child, or another loved one in the hands of an app dependent on a server you cannot touch, control, or know the status of, is utterly unacceptable.

Tuesday, September 17th, 2019

Geneva Copenhagen Amsterdam

Back in the late 2000s, I used to go to Copenhagen every for an event called Reboot. It was a fun, eclectic mix of talks and discussions, but alas, the last one was over a decade ago.

It was organised by Thomas Madsen-Mygdal. I hadn’t seen Thomas in years, but then, earlier this year, our paths crossed when I was back at CERN for the 30th anniversary of the web. He got a real kick out of the browser recreation project I was part of.

I few months ago, I got an email from Thomas about the new event he’s running in Copenhagen called Techfestival. He was wondering if there was some way of making the WorldWideWeb project part of the event. We ended up settling on having a stand—a modern computer running a modern web browser running a recreation of the first ever web browser from almost three decades ago.

So I showed up at Techfestival and found that the computer had been set up in a Shoreditchian shipping container. I wasn’t exactly sure what I was supposed to do, so I just hung around nearby until someone wandering by would pause and start tentatively approaching the stand.

If you’re at Techfestival.co in Copenhagen, drop in to this shipping container where I’ll be demoing WorldWideWeb.cern.ch

“Would you like to try the time machine?” I asked. Nobody refused the offer. I explained that they were looking at a recreation of the world’s first web browser, and then showed them how they could enter a URL to see how the oldest web browser would render a modern website.

Lots of people entered facebook.com or google.com, but some people had their own websites, either personal or for their business. They enjoyed seeing how well (or not) their pages held up. They’d take photos of the screen.

People asked lots of questions, which I really enjoyed answering. After a while, I was able to spot the themes that came up frequently. Some people were confusing the origin story of the internet with the origin story of the web, so I was more than happy to go into detail on either or both.

The experience helped me clarify in my own mind what was exciting and interesting about the birth of the web—how much has changed, and how much and stayed the same.

All of this very useful fodder for a conference talk I’m putting together. This will be a joint talk with Remy at the Fronteers conference in Amsterdam in a couple of weeks. We’re calling the talk How We Built the World Wide Web in Five Days:

The World Wide Web turned 30 years old this year. To mark the occasion, a motley group of web nerds gathered at CERN, the birthplace of the web, to build a time machine. The first ever web browser was, confusingly, called WorldWideWeb. What if we could recreate the experience of using it …but within a modern browser! Join (Je)Remy on a journey through time and space and code as they excavate the foundations of Tim Berners-Lee’s gloriously ambitious and hacky hypertext system that went on to conquer the world.

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.

We’ve been honing the material and doing some run-throughs at the Clearleft HQ at 68 Middle Street this week. The talk has a somewhat unusual structure with two converging timelines. I think it’s going to work really well, but I won’t know until we actually deliver the talk in Amsterdam. I’m excited—and a bit nervous—about it.

Whether it’s in a shipping container in Copenhagen or on a stage in Amsterdam, I’m starting to realise just how much I enjoy talking about web history.

A Love Letter to Net.Art - The History of the Web

Click around the site a bit and you’ll find yourself tied to an endless string of hyperlinks, hopping from one page to the next, with no real rhyme or reason to tie them altogether. It is almost pure web id, unleashed structurally to engage your curiosity and make use of the web’s most primal feature: the link.

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.