It’s always good seeing behind the scenes of stuff you love. More so if there’s good engineering involved, so I enjoyed this pair of videos from Spotify. Lots of overlap with Creativity, Inc. too, unsurprisingly. This is how people make things now.
This week we launched a thing I’ve been working on for the last few months, alongside a brilliant little team of colleagues and freelancers.
PaperLater lets you save the good bits of the web to print, so you can enjoy them away from the screen. If you’ve used something like Instapaper, Pocket or Readability before, it’s a bit like that, but in print.
It’s a really nice scale of product to have built. We solved some gnarly technical problems (automated layout/typography, single copy print production, content extraction), but it’s distilled into what’s really quite a small web app. There’s only a handful of pages, and we’ve tried to make the whole experience feel really light and easy. Time will tell us whether we’ve got that right, but I’m proud of that.
It’s nice to realise that we’re getting better at launching things. Little things make it easier: knowing to get nice photos shot before launch; having a customer support system to bolt into; having an existing framework for legal documents; and so on.
I’m also getting comfortable with patterns and tools that reduce the numbers of things I need to think about, and let me concentrate on building the thing at hand. I’m never changing my text editor again, for example. That’s a good feeling, and only taken a decade.
I think of PaperLater a bit like podcasts. I don’t really listen to podcasts, not because I don’t like them, but there just isn’t a podcast shaped hole in my life. But there is a PaperLater shaped hole, and we built it because our hunch is there’s one in other people’s lives too. If there’s one in yours, I hope you enjoy it.
I liked this post by Sam Stokes about ‘What Programming is Like‘.
I usually describe programming as like world-building. You imagine a cartoon world with its own laws of physics. You build the objects that inhabit that world, and rules that govern it. And then you get real people to come and play in it. You watch what they do, and see whether the right things happen. And then you fiddle with it all, and go round again.
Actually, that sounds really tedious.
As you should do with any grown-up piece of software, we put in an error logging system, so if someone manages to trigger a error, we get notified of it and can try to fix it.
We’re using the
window.onerror callback, which takes three arguments: the error message, the URL of the script that triggered it, and the line number. On some browsers there are two more parameters: the column (useful for heavily minified code) and the error object, but that’s a fairly recent addition to the spec and not widely supported.
It became quickly obvious that some people have pretty odd browser setups. We spent a while trying to track down errors which turned out not to be in our code, or in any code on that page anywhere. These turned out to be from two sources: JS injected by HTTP proxies, and JS injected by browser extensions.
We fixed the problems with JS injected by HTTP proxies by running the whole application over SSL/TLS. The performance impact is negligible and a whole class of errors disappeared immediately.
And we fixed the problems caused by browser extensions by ignoring all script URLs outside of our domain and that of our CDN. They’ll still cause errors that’ll be visible in the console, but our code won’t trap and log them.
We ended up with a
window.onerror function that looks a bit like this:
There’s a few things going on here. Firstly, we’re only catching the error the first time the browser throws an exception, so we don’t get swamped. Secondly, we’re calling our own
ARTHR.log function which switches between local and remote logging, depending on the environment. In production it logs to the server over AJAX, so an entry appears in our logging system and in some situations an email is sent out to the team.
The code that displays the error to the user, and the code that sends the log message, are both executed using setTimeout with a short interval (10ms). This makes them run asynchronously, and ensures that the failure of one to execute (due to a bug or an odd situation) doesn’t prevent the other from running.
We still get a class of errors that are difficult to trace. Dumping the entire state of the application might be helpful here, including a snapshot of the DOM, all the bound events and so on. That might be straightforward, but I’ve not looked into it.
It’s often better to try and catch exceptions deeper into the code, rather than letting
window.onerror handle it, but for unknown unknowns, this is a useful tool in the debugging arsenal. If you’ve got your own version of this, or there’s a much smarter way of handling JS error tracking, I’d love to hear it.
I choose to believe that somewhere out there there’s a freelance book designer on a mission. Their goal is to fight the homogeneity of modern cover design, and roll back the oppression forced upon them by the Big Publishers.
But you can’t slip an act of rebellion past just any old client. You have to pick your moment and find one so incompetent that they’ve never looked at a bookshelf before.
(I had a look at my bookshelf at home, and the only two books that do this are French and Spanish. Is this a foreign thing?)
Much like Alice, every now and again someone says to me: “you still doing that newspaper thing”? Yes, yes I am! Still!
It’s year five now, pretty much. I didn’t think I’d ever do a thing this long. I might never again. But it turns out businesses are hard, especially when they involve atoms and even more so if you want to be profitable, legal and have good customer service. Not that much of that is to do with me.
We’ve just launched one of the things I naively thought we’d be doing in the second year: selling print-on-demand newspapers from our site, with a nice profit sharing arrangement. This means you can, for example, grab a bunch of your favourite posts from your blog, put them into ARTHR to do a quick layout, print a single copy to check it all over, then start selling it from our site. We take our cut and send you your cut shortly after.
And we’re running a small beta test of a personalised newspaper service. I can’t say too much about that yet (other than it’s a lot of fun), because we’re still working out the shape of it, but if you think something like that might work for [your large media organisation], we should have a chat.
So it’s good. And hard. But good.
“adequate responses, including of a technical and technological nature”
From. Pretty much describes my job.
Still shooting film. Still enjoying it. If I get one good shot out of a roll I’m happy.
I’ve been using Eye Culture in Bethnal Green for processing and scans. High res JPEGs are about £6/roll. They do a good job.