Journal tags: publishing

85

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Feeds

A little while back, Marcus Herrmann wrote about making RSS more visible again with a /feeds page. Here’s his feeds page. Here’s Remy’s.

Seems like a good idea to me. I’ve made mine:

adactio.com/feeds

As well as linking to the usual RSS feeds (blog posts, links, notes), it’s also got an explanation of how you can subscribe to a customised RSS feed using tags.

Then, earlier today, I was chatting with Matt on Twitter and he asked:

btw do you share your blogroll anywhere?

So now I’ve added another URL:

adactio.com/feeds/subscriptions

That’s got a link to my OPML file, exported from my feed reader, and a list of the (current) RSS feeds that I’m subscribed to.

I like the idea of blogrolls making a comeback. And webrings.

100 tunes

We got a headstart on the lockdown. A week before the UK government finally stopped dilly-dallying (at the expense of tens of thousands of lives), Clearleft became a remote-only company. At the beginning of this stay-at-home time, I started recording a tune a day. I wasn’t sure how long I’d keep it up, but I’ve managed to keep it going the whole time.

Yesterday I recorded my 100th tune.

It’s funny how small efforts can build up into a satisfying corpus. It’s not like I’m attempting anything ambitious, like Matthias, who is doing 100 days of writing. Recording one tune isn’t too much hassle. There are days when it’s frustrating and I have to do multiple takes, but overall it’s not too taxing. But now, when I look at the cumulative result, I’m very happy that I didn’t skip any days.

One hundred is a nice round number, so this could be a good time to stop. I could quit while I’m ahead. But I think I’ll keep going. Again, despite what the official line might be from the UK government (who have lost all trust), I reckon I’ll be staying at home for a while yet. As long as I’m here, I may as well keep playing. I have plenty more tunes to play.

At some point, the daily streak will end. But even then, I think I’ll continue to record tunes like this, even if it becomes more sporadic.

If you like these tunes, as well as being here on my own site, they’re all in a YouTube set. So …like’n’subscribe, or something?

A decade apart

Today marks ten years since the publication of HTML5 For Web Designers, the very first book from A Book Apart.

I’m so proud of that book, and so honoured that I was the first author published by the web’s finest purveyors of brief books. I mean, just look at the calibre of their output since my stumbling start!

Here’s what I wrote ten years ago.

Here’s what Jason wrote ten years ago.

Here’s what Mandy wrote ten years ago.

Here’s what Jeffrey wrote ten years ago.

They started something magnificent. Ten years on, with Katel at the helm, it’s going from strength to strength.

Happy birthday, little book! And happy birthday, A Book Apart! Here’s to another decade!

A Book Apart authors, 1-6

Reading

At the beginning of the year, Remy wrote about extracting Goodreads metadata so he could create his end-of-year reading list. More recently, Mark Llobrera wrote about how he created a visualisation of his reading history. In his case, he’s using JSON to store the information.

This kind of JSON storage is exactly what Tom Critchlow proposes in his post, Library JSON - A Proposal for a Decentralized Goodreads:

Thinking through building some kind of “web of books” I realized that we could use something similar to RSS to build a kind of decentralized GoodReads powered by indie sites and an underlying easy to parse format.

His proposal looks kind of similar to what Mark came up with. There’s a title, an author, an image, and some kind of date for when you started and/or finished reading the book.

Matt then points out that RSS gets close to the data format being suggested and asks how about using RSS?:

Rather than inventing a new format, my suggestion is that this is RSS plus an extension to deal with books. This is analogous to how the podcast feeds are specified: they are RSS plus custom tags.

Like Matt, I’m in favour of re-using existing wheels rather than inventing new ones, mostly to avoid a 927 situation.

But all of these proposals—whether JSON or RSS—involve the creation of a separate file, and yet the information is originally published in HTML. Along the lines of Matt’s idea, I could imagine extending the h-entry collection of class names to allow for books (or films, or other media). It already handles images (with u-photo). I think the missing fields are the date-related ones: when you start and finish reading. Those fields are present in a different microformat, h-event in the form of dt-start and dt-end. Maybe they could be combined:


<article class="h-entry h-event h-review">
<h1 class="p-name p-item">Book title</h1>
<img class="u-photo" src="image.jpg" alt="Book cover.">
<p class="p-summary h-card">Book author</p>
<time class="dt-start" datetime="YYYY-MM-DD">Start date</time>
<time class="dt-end" datetime="YYYY-MM-DD">End date</time>
<div class="e-content">Remarks</div>
<data class="p-rating" value="5">★★★★★</data>
<time class="dt-published" datetime="YYYY-MM-DDThh:mm">Date of this post</time>
</article>

That markup is simultaneously a post (h-entry) and an event (h-event) and you can even throw in h-card for the book author (as well as h-review if you like to rate the books you read). It can be converted to RSS and also converted to .ics for calendars—those parsers are already out there. It’s ready for aggregation and it’s ready for visualisation.

I publish very minimal reading posts here on adactio.com. What little data is there isn’t very structured—I don’t even separate the book title from the author. But maybe I’ll have a little play around with turning these h-entries into combined h-entry/event posts.

Abolish Silicon Valley by Wendy Liu

I got an email a little while back from Michael at Repeater Books asking me if I wanted an advance copy of Abolish Silicon Valley: How to Liberate Technology From Capitalism by Wendy Liu. Never one to look a gift horse in the mouth, I said “Sure!”

I’m happy to say that the book is most excellent …or at least mostly excellent.

Contrary to what the book title—or its blurb—might tell you, this is a memoir first and foremost. It’s a terrific memoir. It’s utterly absorbing.

Just as the most personal songs can have the most universal appeal, this story feels deeply personal while being entirely accessible. You don’t have to be a computer nerd to sympathise with the struggles of a twenty-something in a start-up trying to make sense of the world. This well-crafted narrative will resonate with any human. It calls to mind Ellen Ullman’s excellent memoir, Close to the Machine—not a comparison I make lightly.

But as you might have gathered from the book’s title, Abolish Silicon Valley isn’t being marketed as a memoir:

Abolish Silicon Valley is both a heartfelt personal story about the wasteful inequality of Silicon Valley, and a rallying call to engage in the radical politics needed to upend the status quo.

It’s true that the book finishes with a political manifesto but that’s only in the final chapter or two. The majority of the book is the personal story, and just as well. Those last few chapters really don’t work in this setting. They feel tonally out of place.

Don’t get me wrong, the contents of those final chapters are right up my alley—they’re preaching to the converted here. But I think they would be better placed in their own publication. The heavily-researched academic style jars with the preceeding personal narrative.

Abolish Silicon Valley is 80% memoir and 20% manifesto. I worry that the marketing isn’t making that clear. It would be a shame if this great book didn’t find its audience.

The book will be released on April 14th. It’s available to pre-order now. I highly recommend doing just that. I think you’ll really enjoy it. But if you get mired down in the final few chapters, know that you can safely skip them.

Three books

Lurking: How a Person Became a User by Joanne McNeil will be published on February 25th.

In Lurking, Joanne McNeil digs deep and identifies the primary (if sometimes contradictory) concerns of people online: searching, safety, privacy, identity, community, anonymity, and visibility. She charts what it is that brought people online and what keeps us here even as the social equations of digital life—what we’re made to trade, knowingly or otherwise, for the benefits of the internet—have shifted radically beneath us. It is a story we are accustomed to hearing as tales of entrepreneurs and visionaries and dynamic and powerful corporations, but there is a more profound, intimate story that hasn’t yet been told.

Enemy of All Mankind: A True Story of Piracy, Power, and History’s First Global Manhunt by Steven Johnson will be published on May 12th:

Henry Every was the seventeenth century’s most notorious pirate. The press published wildly popular—and wildly inaccurate—reports of his nefarious adventures. The British government offered enormous bounties for his capture, alive or (preferably) dead. But Steven Johnson argues that Every’s most lasting legacy was his inadvertent triggering of a major shift in the global economy. Enemy of All Mankind focuses on one key event—the attack on an Indian treasure ship by Every and his crew—and its surprising repercussions across time and space. It’s the gripping tale one of the most lucrative crimes in history, the first international manhunt, and the trial of the seventeenth century.

How To Future: Leading and Sense-Making in an Age of Hyperchange by Scott Smith with Madeline Ashby will be published on July 3rd:

Successfully designing for a future requires a picture of that future—a useful map of the horizons ahead that can be used for wayfinding, identifying emerging opportunities or risks. Accurately developing this map means investing in better awareness of signals about the future, understanding trends in context, developing rich insights about what those signals indicate—relative to companies, people, citizens or stakeholders. It also means cultivating ways to share these future insights through tangible yet provocative scenarios or stories, turn these into prototypes, or connect them to strategies.

2019 in numbers

I posted to adactio.com 1,600 times in 2019: sparkline

In amongst those notes were:

If you like, you can watch all that activity plotted on a map.

map

Away from this website in 2019:

Words I wrote in 2019

I wrote just over one hundred blog posts in 2019. That’s even more than I wrote in 2018, which I’m very happy with.

Here are eight posts from during the year that I think are a good representative sample. I like how these turned out.

I hope that I’ll write as many blog posts in 2020.

I’m pretty sure that I will also continue to refer to them as blog posts, not blogs. I may be the last holdout of this nomenclature in 2020. I never planned to die on this hill, but here we are.

Actually, seeing as this is technically my journal rather than my blog, I’ll just call them journal entries.

Here’s to another year of journal entries.

The trimCache function in Going Offline …again

It seems that some code that I wrote in Going Offline is haunted. It’s the trimCache function.

First, there was the issue of a typo. Or maybe it’s more of a brainfart than a typo, but either way, there’s a mistake in the syntax that was published in the book.

Now it turns out that there’s also a problem with my logic.

To recap, this is a function that takes two arguments: the name of a cache, and the maximum number of items that cache should hold.

function trimCache(cacheName, maxItems) {

First, we open up the cache:

caches.open(cacheName)
.then( cache => {

Then, we get the items (keys) in that cache:

cache.keys()
.then(keys => {

Now we compare the number of items (keys.length) to the maximum number of items allowed:

if (keys.length > maxItems) {

If there are too many items, delete the first item in the cache—that should be the oldest item:

cache.delete(keys[0])

And then run the function again:

.then(
    trimCache(cacheName, maxItems)
);

A-ha! See the problem?

Neither did I.

It turns out that, even though I’m using then, the function will be invoked immediately, instead of waiting until the first item has been deleted.

Trys helped me understand what was going on by making a useful analogy. You know when you use setTimeout, you can’t put a function—complete with parentheses—as the first argument?

window.setTimeout(doSomething(someValue), 1000);

In that example, doSomething(someValue) will be invoked immediately—not after 1000 milliseconds. Instead, you need to create an anonymous function like this:

window.setTimeout( function() {
    doSomething(someValue)
}, 1000);

Well, it’s the same in my trimCache function. Instead of this:

cache.delete(keys[0])
.then(
    trimCache(cacheName, maxItems)
);

I need to do this:

cache.delete(keys[0])
.then( function() {
    trimCache(cacheName, maxItems)
});

Or, if you prefer the more modern arrow function syntax:

cache.delete(keys[0])
.then( () => {
    trimCache(cacheName, maxItems)
});

Either way, I have to wrap the recursive function call in an anonymous function.

Here’s a gist with the updated trimCache function.

What’s annoying is that this mistake wasn’t throwing an error. Instead, it was causing a performance problem. I’m using this pattern right here on my own site, and whenever my cache of pages or images gets too big, the trimCaches function would get called …and then wouldn’t stop running.

I’m very glad that—witht the help of Trys at last week’s Homebrew Website Club Brighton—I was finally able to get to the bottom of this. If you’re using the trimCache function in your service worker, please update the code accordingly.

Management regrets the error.

Other people’s weeknotes

Paul is writing weeknotes. Here’s his latest.

Amy is writing weeknotes. Here’s her latest.

Aegir is writing weeknotes. Here’s his latest.

Nat is writing weeknotes. Here’s their latest.

Alice is writing weeknotes. Here’s her latest.

Mark is writing weeknotes. Here’s his latest.

I enjoy them all.

2018 in numbers

I posted to adactio.com 1,387 times in 2018: sparkline

In amongst those notes were:

In my blog posts, the top tags were:

  1. frontend and development (42 posts), sparkline
  2. serviceworkers (27 posts), sparkline
  3. design (20 posts), sparkline
  4. writing and publishing (19 posts), sparkline
  5. javascript (18 posts). sparkline

In my links, the top tags were:

  1. development (305 links), sparkline
  2. frontend (289 links), sparkline
  3. design (178 links), sparkline
  4. css (110 links), sparkline
  5. javascript (106 links). sparkline

When I wasn’t updating this site:

But these are just numbers. To get some real end-of-year thoughts, read posts by Remy, Andy, Ana, or Bill Gates.

Words I wrote in 2018

I wrote just shy of a hundred blog posts in 2018. That’s an increase from 2017. I’m happy about that.

Here are some posts that turned out okay…

A lot of my writing in 2018 was on technical topics—front-end development, service workers, and so on—but I should really make more of an effort to write about a wider range of topics. I always like when Zeldman writes about his glamourous life. Maybe in 2019 I’ll spend more time letting you know what I had for lunch.

I really enjoy writing words on this website. If I go too long between blog posts, I start to feel antsy. The only relief is to move my fingers up and down on the keyboard and publish something. Sounds like a bit of an addiction, doesn’t it? Well, as habits go, this is probably one of my healthier ones.

Thanks for reading my words in 2018. I didn’t write them for you—I wrote them for me—but it’s always nice when they resonate with others. I’ll keep on writing my brains out in 2019.

Webmentions at Indie Web Camp Berlin

I was in Berlin for most of last week, and every day was packed with activity:

By the time I got back to Brighton, my brain was full …just in time for FF Conf.

All of the events were very different, but equally enjoyable. It was also quite nice to just attend events without speaking at them.

Indie Web Camp Berlin was terrific. There was an excellent turnout, and once again, I found that the format was just right: a day of discussions (BarCamp style) followed by a day of doing (coding, designing, hacking). I got very inspired on the first day, so I was raring to go on the second.

What I like to do on the second day is try to complete two tasks; one that’s fairly straightforward, and one that’s a bit tougher. That way, when it comes time to demo at the end of the day, even if I haven’t managed to complete the tougher one, I’ll still be able to demo the simpler one.

In this case, the tougher one was also tricky to demo. It involved a lot of invisible behind-the-scenes plumbing. I was tweaking my webmention endpoint (stop sniggering—tweaking your endpoint is no laughing matter).

Up until now, I could handle straightforward webmentions, and I could handle updates (if I receive more than one webmention from the same link, I check it each time). But I needed to also handle deletions.

The spec is quite clear on this. A 404 isn’t enough to trigger a deletion—that might be a temporary state. But a status of 410 Gone indicates that a resource was once here but has since been deliberately removed. In that situation, any stored webmentions for that link should also be removed.

Anyway, I think I got it working, but it’s tricky to test and even trickier to demo. “Not to worry”, I thought, “I’ve always got my simpler task.”

For that, I chose to add a little map to my homepage showing the last location I published something from. I’ve been geotagging all my content for years (journal entries, notes, links, articles), but not really doing anything with that data. This is a first step to doing something interesting with many years of location data.

I’ve got it working now, but the demo gods really weren’t with me at Indie Web Camp. Both of my demos failed. The webmention demo failed quite embarrassingly.

As well as handling deletions, I also wanted to handle updates where a URL that once linked to a post of mine no longer does. Just to be clear, the URL still exists—it’s not 404 or 410—but it has been updated to remove the original link back to one of my posts. I know this sounds like another very theoretical situation, but I’ve actually got an example of it on my very first webmention test post from five years ago. Believe it or not, there’s an escort agency in Nottingham that’s using webmention as a vector for spam. They post something that does link to my test post, send a webmention, and then remove the link to my test post. I almost admire their dedication.

Still, I wanted to foil this particular situation so I thought I had updated my code to handle it. Alas, when it came time to demo this, I was using someone else’s computer, and in my attempt to right-click and copy the URL of the spam link …I accidentally triggered it. In front of a room full of people. It was midly NSFW, but more worryingly, a potential Code Of Conduct violation. I’m very sorry about that.

Apart from the humiliating demo, I thoroughly enjoyed Indie Web Camp, and I’m going to keep adjusting my webmention endpoint. There was a terrific discussion around the ethical implications of storing webmentions, led by Sebastian, based on his epic post from earlier this year.

We established early in the discussion that we weren’t going to try to solve legal questions—like GDPR “compliance”, which varies depending on which lawyer you talk to—but rather try to figure out what the right thing to do is.

Earlier that day, during the introductions, I quite happily showed webmentions in action on my site. I pointed out that my last blog post had received a response from another site, and because that response was marked up as an h-entry, I displayed it in full on my site. I thought this was all hunky-dory, but now this discussion around privacy made me question some inferences I was making:

  1. By receiving a webention in the first place, I was inferring a willingness for the link to be made public. That’s not necessarily true, as someone pointed out: a CMS could be automatically sending webmentions, which the author might be unaware of.
  2. If the linking post is marked up in h-entry, I was inferring a willingness for the content to be republished. Again, not necessarily true.

That second inferrence of mine—that publishing in a particular format somehow grants permissions—actually has an interesting precedent: Google AMP. Simply by including the Google AMP script on a web page, you are implicitly giving Google permission to store a complete copy of that page and serve it from their servers instead of sending people to your site. No terms and conditions. No checkbox ticked. No “I agree” button pressed.

Just sayin’.

Anyway, when it comes to my own processing of webmentions, I’m going to take some of the suggestions from the discussion on board. There are certain signals I could be looking for in the linking post:

  • Does it include a link to a licence?
  • Is there a restrictive robots.txt file?
  • Are there meta declarations that say noindex?

Each one of these could help to infer whether or not I should be publishing a webmention or not. I quickly realised that what we’re talking about here is an algorithm.

Despite its current usage to mean “magic”, an algorithm is a recipe. It’s a series of steps that contribute to a decision point. The problem is that, in the case of silos like Facebook or Instagram, the algorithms are secret (which probably contributes to their aura of magical thinking). If I’m going to write an algorithm that handles other people’s information, I don’t want to make that mistake. Whatever steps I end up codifying in my webmention endpoint, I’ll be sure to document them publicly.

Several people are writing

Anne Gibson writes:

It sounds easy to make writing a habit, but like every other habit that doesn’t involve addictive substances like nicotine or dopamine it’s hard to start and easy to quit.

Alice Bartlett writes:

Anyway, here we are, on my blog, or in your RSS reader. I think I’ll do weaknotes. Some collections of notes. Sometimes. Not very well written probably. Generally written with the urgency of someone who is waiting for a baby wake up.

Patrick Rhone writes:

Bottom line; please place any idea worth more than 280 characters and the value Twitter places on them (which is zero) on a blog that you own and/or can easily take your important/valuable/life-changing ideas with you and make them easy for others to read and share.

Sara Soueidan writes:

What you write might help someone understand a concept that you may think has been covered enough before. We each have our own unique perspectives and writing styles. One writing style might be more approachable to some, and can therefore help and benefit a large (or even small) number of people in ways you might not expect.

Just write.

Even if only one person learns something from your article, you’ll feel great, and that you’ve contributed — even if just a little bit — to this amazing community that we’re all constantly learning from. And if no one reads your article, then that’s also okay. That voice telling you that people are just sitting somewhere watching our every step and judging us based on the popularity of our writing is a big fat pathetic attention-needing liar.

Laura Kalbag writes:

The web can be used to find common connections with folks you find interesting, and who don’t make you feel like so much of a weirdo. It’d be nice to be able to do this in a safe space that is not being surveilled.

Owning your own content, and publishing to a space you own can break through some of these barriers. Sharing your own weird scraps on your own site makes you easier to find by like-minded folks.

Brendan Dawes writes:

At times I think “will anyone reads this, does anyone care?”, but I always publish it anyway — and that’s for two reasons. First it’s a place for me to find stuff I may have forgotten how to do. Secondly, whilst some of this stuff is seemingly super-niche, if one person finds it helpful out there on the web, then that’s good enough for me. After all I’ve lost count of how many times I’ve read similar posts that have helped me out.

Robin Rendle writes:

My advice after learning from so many helpful people this weekend is this: if you’re thinking of writing something that explains a weird thing you struggled with on the Internet, do it! Don’t worry about the views and likes and Internet hugs. If you’ve struggled with figuring out this thing then be sure to jot it down, even if it’s unedited and it uses too many commas and you don’t like the tone of it.

Khoi Vinh writes:

Maybe you feel more comfortable writing in short, concise bullets than at protracted, grandiose length. Or maybe you feel more at ease with sarcasm and dry wit than with sober, exhaustive argumentation. Or perhaps you prefer to knock out a solitary first draft and never look back rather than polishing and tweaking endlessly. Whatever the approach, if you can do the work to find a genuine passion for writing, what a powerful tool you’ll have.

Amber Wilson writes:

I want to finally begin writing about psychology. A friend of mine shared his opinion that writing about this is probably best left to experts. I tried to tell him I think that people should write about whatever they want. He argued that whatever he could write about psychology has probably already been written about a thousand times. I told him that I’m going to be writer number 1001, and I’m going to write something great that nobody has written before.

Austin Kleon writes:

Maybe I’m weird, but it just feels good. It feels good to reclaim my turf. It feels good to have a spot to think out loud in public where people aren’t spitting and shitting all over the place.

Tim Kadlec writes:

I write to understand and remember. Sometimes that will be interesting to others, often it won’t be.

But it’s going to happen. Here, on my own site.

You write…

Links, tags, and feeds

A little while back, I switched from using Chrome as my day-to-day browser to using Firefox. I could feel myself getting a bit too comfortable with one particular browser, and that’s not good. I reckon it’s good to shake things up a little every now and then. Besides, there really isn’t that much difference once you’ve transferred over bookmarks and cookies.

Unfortunately I’m being bitten by this little bug in Firefox. It causes some of my bookmarklets to fail on certain sites with strict Content Security Policies (and CSPs shouldn’t affect bookmarklets). I might have to switch back to Chrome because of this.

I use bookmarklets throughout the day. There’s the Huffduffer bookmarklet, of course, for whenever I come across a podcast episode or other piece of audio that I want to listen to later. But there’s also my own home-rolled bookmarklet for posting links to my site. It doesn’t do anything clever—it grabs the title and URL of the currently open page and pre-populates a form in a new window, leaving me to add a short description and some tags.

If you’re reading this, then you’re familiar with the “journal” section of adactio.com, but the “links” section is where I post the most. Here, for example, are all the links I posted yesterday. It varies from day to day, but there’s generally a handful.

Should you wish to keep track of everything I’m linking to, there’s a twitterbot you can follow called @adactioLinks. It uses a simple IFTTT recipe to poll my RSS feed of links and send out a tweet whenever there’s a new entry.

Or you can drink straight from the source and subscribe to the RSS feed itself, if you’re still rocking it old-school. But if RSS is your bag, then you might appreciate a way to filter those links…

All my links are tagged. Heavily. This is because all my links are “notes to future self”, and all my future self has to do is ask “what would past me have tagged that link with?” when I’m trying to find something I previously linked to. I end up using my site’s URLs as an interface:

At the front-end gatherings at Clearleft, I usually wrap up with a quick tour of whatever I’ve added that week to:

Well, each one of those tags also has a corresponding RSS feed:

…and so on.

That means you can subscribe to just the links tagged with something you’re interested in. Here’s the full list of tags if you’re interested in seeing the inside of my head.

This also works for my journal entries. If you’re only interested in my blog posts about frontend development, you might want to subscribe to:

Here are all the tags from my journal.

You can even mix them up. For everything I’ve tagged with “typography”—whether it’s links, journal entries, or articles—the URL is:

The corresponding RSS feed is:

You get the idea. Basically, if something on my site is a list of items, chances are there’s a corresponding RSS feeds. Sometimes there might even be a JSON feed. Hack some URLs to see.

Meanwhile, I’ll be linking, linking, linking…

The trimCache function in Going Offline

Paul Yabsley wrote to let me know about an error in Going Offline. It’s rather embarrassing because it’s code that I’m using in the service worker for adactio.com but for some reason I messed it up in the book.

It’s the trimCache function in Chapter 7: Tidying Up. That’s the reusable piece of code that recursively reduces the number of items in a specified cache (cacheName) to a specified amount (maxItems). On page 95 and 96 I describe the process of creating the function which, in the book, ends up like this:

 function trimCache(cacheName, maxItems) {
   cacheName.open( cache => {
     cache.keys()
     .then( items => {
       if (items.length > maxItems) {
         cache.delete(items[0])
         .then(
           trimCache(cacheName, maxItems)
         ); // end delete then
       } // end if
     }); // end keys then
   }); // end open
 } // end function

See the problem? It’s right there at the start when I try to open the cache like this:

cacheName.open( cache => {

That won’t work. The open method only works on the caches object—I should be passing the name of the cache into the caches.open method. So the code should look like this:

caches.open( cacheName )
.then( cache => {

Everything else remains the same. The corrected trimCache function is here:

function trimCache(cacheName, maxItems) {
  caches.open(cacheName)
  .then( cache => {
    cache.keys()
    .then(items => {
      if (items.length > maxItems) {
        cache.delete(items[0])
        .then(
          trimCache(cacheName, maxItems)
        ); // end delete then
      } // end if
    }); // end keys then
  }); // end open then
} // end function

Sorry about that! I must’ve had some kind of brainfart when I was writing (and describing) that one line of code.

You may want to deface your copy of Going Offline by taking a pen to that code example. Normally I consider the practice of writing in books to be barbarism, but in this case …go for it.

Update: There was another error in the code for trimCache! Here’s the fix.

New tools for art direction on the web

I’m in Boston right now, getting ready to speak at An Event Apart. This will be my second (and last) Event Apart of the year—the other time was in Seattle back in April. After that event, I wrote about how inspired I was:

It was interesting to see repeating, overlapping themes. From a purely technical perspective, three technologies that were front and centre were:

  • CSS grid,
  • variable fonts, and
  • service workers.

From listening to other attendees, the overwhelming message received was “These technologies are here—they’ve arrived.”

I was itching to combine those technologies on a project. Coincidentally, it was around that time that I started planning to publish The Gęsiówka Story. I figured I could use that as an opportunity to tinker with those front-end technologies that I was so excited about.

But I was cautious. I didn’t want to use the latest exciting technology just for the sake of it. I was very aware of the gravity of the material I was dealing with. Documenting the story of Gęsiówka was what mattered. Any front-end technologies I used had to be in support of that.

First of all, there was the typesetting. I don’t know about you, but I find choosing the right typefaces to be overwhelming. Despite all the great tips and techniques out there for choosing and pairing typefaces, I still find myself agonising over the choice—what if there’s a better choice that I’m missing?

In this case, because I wanted to use a variable font, I had a constraint that helped reduce the possibility space. I started to comb through v-fonts.com to find a suitable typeface—I was fairly sure I wanted a serious serif.

I had one other constraint. The font file had to include English, Polish, and German glyphs. That pretty much sealed the deal for Source Serif. That only has one variable axis—weight—but I decided that this could also be an interesting constraint: how much could I wrangle out of a single typeface just using various weights?

I ended up using font weights of 75, 250, 315, 325, 340, 350, 400, and 525. Most of them were for headings or one-off uses, with a font-weight of 315 for the body copy.

(And can I just say once again how impressed I am that the founding fathers of CSS were far-sighted enough to keep those font weight ranges free for future use?)

Getting the typography right posed an interesting challenge. This was a fairly long piece of writing, so it really needed to be readable without getting tiring. But at the same time, I didn’t want it to be exactly pleasant to read—that wouldn’t do the subject matter justice. I wanted the reader to feel the seriousness of the story they were reading, without being fatigued by its weight.

Colour and type went a long way to communicating that feeling. The grid sealed the deal.

The Gęsiówka Story is mostly one single column of text, so on the face of it, there isn’t much opportunity to go crazy with CSS Grid. But I realised I could use a grid to create a winding effect for the text. I had to be careful though: I didn’t want it to become uncomfortable to read. I wanted to create a slightly unsettling effect.

Every section element is turned into a seven-column grid container:

section {
    display: grid;
    grid-column-gap: 2em;
    grid-template-columns: 2em repeat(5, 1fr) 2em;
}

The first and last columns are the same width as the gutters (2em), effectively creating “outer” gutters for the grid. Each paragraph within the section takes up six of the seven columns. I use nth-of-type to alternate which six columns are used (the first six or the last six). That creates the staggered indendation:

section > p {
    grid-column: 1/7;
}
section > p:nth-of-type(even) {
    grid-column: 2/8;
}

Staggered grid.

That might seem like overkill just to indent every second paragraph by 4em, but I then used the same grid dimensions to layout figure elements with images and captions.

section > figure {
    display: grid;
    grid-column-gap: 2em;
    grid-template-columns: 2em repeat(5, 1fr) 2em;
}

Then I can lay out differently proportioned images across different ranges of the grid:

section > figure.landscape > img {
    grid-column: 1/5;
}
section > figure.landscape > figcaption {
    grid-column: 5/8;
}
section > figure.portrait > img {
    grid-column: 1/4;
}
section > figure.portrait > figcaption {
    grid-column: 4/8;
}

Because they’re positioned on the same grid as the paragraphs, everything lines up nicely (and yes, if subgrid existed, I wouldn’t have to redeclare the grid dimensions for the figures).

Finally, I wanted to make sure that the whole thing could be read offline. After all, once you’ve visited the URL once, there’s really no reason to make any more requests to the server. Static documents—and books—are the perfect candidates for an “offline first” approach: always look in the cache, and only go to the network as a last resort.

In this case I used a variation of my minimal viable service worker script, and the result is a very short set of instructions. There’s a little bit of pre-caching going on: I grab the variable font and the HTML page itself (which includes the CSS inlined).

So there you have it: variable fonts, CSS grid, and service workers: three exciting front-end technologies, all of which can be applied as progressive enhancements on top of the core content.

Once again, I find that it’s personal projects that offer the most opportunities to try out new or interesting techniques. And The Gęsiówka Story is a very personal project indeed.

Praise for Going Offline

I’m very, very happy to see that my new book Going Offline is proving to be accessible and unintimidating to a wide audience—that was very much my goal when writing it.

People have been saying nice things on their blogs, which is very gratifying. It’s even more gratifying to see people use the knowledge gained from reading the book to turn those blogs into progressive web apps!

Sara Soueidan:

It doesn’t matter if you’re a designer, a junior developer or an experienced engineer — this book is perfect for anyone who wants to learn about Service Workers and take their Web application to a whole new level.

I highly recommend it. I read the book over the course of two days, but it can easily be read in half a day. And as someone who rarely ever reads a book cover to cover (I tend to quit halfway through most books), this says a lot about how good it is.

Eric Lawrence:

I was delighted to discover a straightforward, very approachable reference on designing a ServiceWorker-backed application: Going Offline by Jeremy Keith. The book is short (I’m busy), direct (“Here’s a problem, here’s how to solve it“), opinionated in the best way (landmine-avoiding “Do this“), and humorous without being confusing. As anyone who has received unsolicited (or solicited) feedback from me about their book knows, I’m an extremely picky reader, and I have no significant complaints on this one. Highly recommended.

Ben Nadel:

If you’re interested in the “offline first” movement or want to learn more about Service Workers, Going Offline by Jeremy Keith is a really gentle and highly accessible introduction to the topic.

Daniel Koskine:

Jeremy nails it again with this beginner-friendly introduction to Service Workers and Progressive Web Apps.

Donny Truong

Jeremy’s technical writing is as superb as always. Similar to his first book for A Book Apart, which cleared up all my confusions about HTML5, Going Offline helps me put the pieces of the service workers’ puzzle together.

People have been saying nice things on Twitter too…

Aaron Gustafson:

It’s a fantastic read and a simple primer for getting Service Workers up and running on your site.

Ethan Marcotte:

Of course, if you’re looking to take your website offline, you should read @adactio’s wonderful book

Lívia De Paula Labate:

Ok, I’m done reading @adactio’s Going Offline book and as my wife would say, it’s the bomb dot com.

If that all sounds good to you, get yourself a copy of Going Offline in paperbook, or ebook (or both).

The Gęsiówka Story

While I was in Warsaw for a conference last week, I sought out a commerative plaque in a residential neighbourhood. The English translation reads:

On 5th August 1944 “Zośka” the scouts’ battalion of the “Radosław” unit Armia Krajowa captured the German concentration camp “Gęsiówka” and liberated 348 Jewish prisoners, citizens of various European countries, many of whom later fought and fell in the Warsaw Uprising.

I knew about the plaque—and the incredible events it commemorates—thanks to a piece of writing called The Gęsiówka Story by Edward Kossoy, a relative of mine.

My ancestral lineage is an unusual mix. I’ve got generations of Irish on my mother’s side, and generations of Eastern European jews on my father’s side.

Edward wasn’t closely related to me. He was my grandfather’s cousin. My father’s father (from whom I got my middle name, Ivan) was driving ambulances in London during the war. Meanwhile his cousin Edward in Poland was trying desperately to get his family out. Separated from his wife and daughter, he was arrested by the Russians in Ukraine and sentenced to hard labour in a gulag. He survived. His wife and child were did not. They were murdered by the nazis during Operation Harvest Festival.

Edward was a lawyer. He spent the rest of his life fighting for reparations for victims of the Holocaust. He represented tens of thousands of jews, Poles, and Roma. He lived in Tel Aviv, Munich, and finally Geneva. That was where he met the Polish war hero Wacław Micuta who first told him about what happened at Gęsiówka. What he heard sounded implausible, but when he found Gęsiówka survivors among his own clientelle, Edward was able to corrobarate Micuta’s story.

(Micuta, by the way, had much to discuss with Edward’s second wife Sonia. She fought in the Warsaw Ghetto uprising, escaping by being smuggled out in a suitcase.)

As well as being a lawyer, Edward was also an author. In 2004 he wrote The Gęsiówka Story for the journal Yad Vashem Studies. I came across it in PDF form while I was searching for more details of Edward’s life and legacy. I was completely astonished by what I read—if it were a Hollywood film, you would think it too far-fetched to be true.

I decided to transfer the story into a more durable format. I’ve marked it up, styled it, and published it here:

gesiowka.adactio.com

The subheading of The Gęsiówka Story is “A Little Known Page of Jewish Fighting History.” I certainly think it’s a piece of history that deserves to be more widely known. That’s why I’ve turned it into a web page.

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. And I think the web is well-suited to documenting the stories and experiences of our forebears.

Edward died six years ago, just one year shy of a hundred. I never got to meet him in person, which is something I very much regret. But by taking his words and working with them while trying my best to treat them with respect, I’ve come to feel a bit closer to this great man.

This was a little labour of love for me. I hope I did his words justice. And I hope you’ll read The Gęsiówka Story.

Service worker resources

At the end of my new book, Going Offline, I have a little collection of resources relating to service workers. Here’s how I introduce them:

If this book were a podcast, then this would be the point at which I would be imploring you to rate me on iTunes (or I’d be telling you about a really good mattress). Instead, I’d like to give you some hyperlinks so that you can explore some of the topics in this brief book in more detail.

It always feels a little strange to publish a list of hyperlinks in a physical book, so I figured I’d republish them here for easy access…

Explanations

Guides

Examples

Progressive web apps

Tools

Documentation