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Great to see somebody finally setting the record straight on bioluminescence and the 50/50 horse-myth. Come on people, it’s 2021!
I’ve been using Synergy for a long, long time. By the time I wrote about my admiration of its notification icon back in 2010 I’d already been using it for some years. But this long love affair ended this week when I made the switch to its competitor, Barrier.
If you’ve not come across it before: Synergy was possibly the first multiplatform tool to provide seamless “edge-to-edge” sharing of a keyboard and mouse between multiple computers. Right now, for example, I’m sitting in front of Cornet, a Debian 11 desktop, Idiophone, a Macbook Pro docked to a desktop monitor, and Renegade, a Windows desktop. And I can move my mouse cursor from one, to the other, to the next, interacting with them all as if I were connected directly to it.
There have long been similar technologies. KVM switches can do this, as can some modern wireless mice (I own at least two such mice!). But none of them are as seamless as what Synergy does: moving from computer to computer as fast as you can move your mouse and sharing a clipboard between multiple devices. I also love that I can configure my set-up around how I work, e.g. when I undock my Macbook it switches from ethernet to wifi, this gets detected and it’s automatically removed from the cluster. So when I pick up my laptop, it magically stops being controlled by my Windows PC’s mouse and keyboard until I dock it again.
Synergy’s published under a hybrid model: open-source components, with paid-for extra features. It used to provide more in the open-source offering: you could download a fully-working copy of the software and use it without limitation, losing out only on a handful of features that for many users were unnecessary. Nontheless, early on I wanted to support the development of this tool that I used so much, and so I donated money towards funding its development. In exchange, I gained access to Synergy Premium, and then when their business model changed I got grandfathered-in to a lifetime subscription to Synergy Pro.
I continued using Synergy all the while. When their problem-stricken 2.x branch went into beta, I was among the testers: despite the stability issues and limitations, I loved the fact that I could have what was functionally multiple co-equal “host” computers, and – when it worked – I liked the slick new configuration interface it sported. I’ve been following with bated breath announcements about the next generation – Synergy 3 – and I’ve registered as an alpha tester for when the time comes.
If it sounds like I’m a fanboy… that’d probably be an accurate assessment of the situation. So why, after all these years, have I jumped ship?
I’ve been aware of Barrier since the project started, as a fork of the last open-source version of the core Synergy program. Initially, I didn’t consider Barrier to be a suitable alternative for me, because it lacked features I cared about that were only available in the premium version of Synergy. As time went on and these features were implemented, I continued to stick with Synergy and didn’t bother to try out Barrier… mostly out of inertia: Synergy worked fine, and the only thing Barrier seemed to offer would be a simpler set-up (because I wouldn’t need to insert my registration details!).
This week, though, as part of a side project, I needed to add an extra computer to my cluster. For reasons that are boring and irrelevant and so I’ll spare you the details, the new computer’s running the 32-bit version of Debian 11.
I went to the Symless download pages and discovered… there isn’t a Debian 11 package. Ah well, I think: the Debian 10 one can probably be made to work. But then I discover… there’s only a 64-bit version of the Debian 10 binary. I’ll note that this isn’t a fundamental limitation – there are 32-bit versions of Synergy available for Windows and for ARMhf Raspberry Pi devices – but a decision by the developers not to support that platform. In order to protect their business model, Synergy is only available as closed-source binaries, and that means that it’s only available for the platforms for which the developers choose to make it available.
So I thought: well, I’ll try Barrier then. Now’s as good a time as any.
Barrier and Synergy aren’t cross-compatible, so first I had to disable Synergy on each machine in my cluster. Then I installed Barrier. Like most popular open-source software, this was
trivially easy compared to Synergy: I just used an appropriate package manager by running choco install barrier, brew install barrier, and apt install barrier to install on each of the Windows, Mac, and Debian computers, respectively.
Configuring Barrier was basically identical to configuring Synergy: set up the machine names, nominate one the server, and tell the server what the relative positions are of each of the others’ screens. I usually bind the “scroll lock” key to the “lock my cursor to the current screen” function but I wasn’t permitted to do this in Barrier for some reason, so I remapped my scroll lock key to some random high unicode character and bound that instead.
Getting Barrier to auto-run on MacOS was a little bit of a drag – in the end I had to use Automator to set up a shortcut that ran it and loaded the configuration, and set that to run on login. These little touches are mostly solved in Synergy, but given its technical audience I don’t imagine that anybody is hugely inconvenienced by them. Nonetheless, Synergy clearly retains a slightly more-polished experience.
Altogether, switching from Synergy to Barrier took me under 15 minutes and has so far offered me a functionally-identical experience, except that it works on more devices, can be installed via my favourite package managers, and doesn’t ask me for registration details before it functions. Synergy 3’s going to have to be a big leap forward to beat that!
For most of 2013/2014 and intermittently thereafter my sister ran a weekly-ish “Family Vlog” on YouTube, and I (even more-intermittently) did an ocasional tonge-in-cheek review and analysis of them.
Today, a friend reported that they had eaten “Sunday dinner on a Wednesday”, and I found myself reminded of a running gag in this old, old vlog… and threw together a quick compilation reel of some of its instances.
Today is “superhero day” for nursery/reception, so I continued my effort to straddle the line between being a fun #parent and an embarassing parent line by dropping the kids off like this:
This checkin to GC9GKJA A Fine Pair # 1625 ~ Eynsham reflects a geocaching.com log entry. See more of Dan's cache logs.
I like to check in on my new caches after about a week in the field to ensure there are no teething troubles with their hiding place/weatherproofing etc. All looks good here!
As you might know if you were paying close attention in Summer 2019, I run a “URL shortener” for my personal use. You may be familiar with public URL shorteners like TinyURL and Bit.ly: my personal URL shortener is basically the same thing, except that only I am able to make short-links with it. Compared to public ones, this means I’ve got a larger corpus of especially-short (e.g. 2/3 letter) codes available for my personal use. It also means that I’m not dependent on the goodwill of a free siloed service and I can add exactly the features I want to it.
For the last nine years my link shortener has been S.2, a tool I threw together in Ruby. It stores URLs in a
sequentially-numbered database table and then uses the Base62-encoding of the primary key as the “code” part of the short URL. Aside from the fact that when I create a short link it shows me a QR code to I can
easily “push” a page to my phone, it doesn’t really have any “special” features. It replaced S.1, from which it primarily differed by putting the code at the end of the URL rather than as part of the domain name, e.g. s.danq.me/a0 rather than a0.s.danq.me: I made the switch
because S.1 made HTTPS a real pain as well as only supporting Base36 (owing to the case-insensitivity of domain names).
But S.2’s gotten a little long in the tooth and as I’ve gotten busier/lazier, I’ve leant into using or adapting open source tools more-often than writing my own from scratch. So this week I switched my URL shortener from S.2 to YOURLS.
One of the things that attracted to me to YOURLS was that it had a ready-to-go Docker image. I’m not the biggest fan of Docker in general, but I do love the convenience of being able to deploy applications super-quickly to my household NAS. This makes installing and maintaining my personal URL shortener much easier than it used to be (and it was pretty easy before!).
Another thing I liked about YOURLS is that it, like S.2, uses Base62 encoding. This meant that migrating my links from S.2 into YOURLS could be done with a simple cross-database
INSERT... SELECT statement:
INSERT INTO yourls.yourls_url(keyword, url, title, `timestamp`, clicks) SELECT shortcode, url, title, created_at, 0 FROM danq_short.links
But do you know what’s a bigger deal for my lifestack than my URL shortener? My RSS reader! I’ve written about it a lot, but I use RSS for just about everything and my feed reader is my first, last, and sometimes only point of contact with the Web! I’m so hooked-in to my RSS ecosystem that I’ll use my own middleware to add feeds to sites that don’t have them, or for which I’m not happy with the feed they provide, e.g. stripping sports out of BBC News, subscribing to webcomics that don’t provide such an option (sometimes accidentally hacking into sites on the way), and generating “complete” archives of series’ of posts so I can use my reader to track my progress.
One of S.1/S.2’s features was that it exposed an RSS feed at a secret URL for my reader to ingest. This was great, because it meant I could “push” something to my RSS reader to read or repost to my blog later. YOURLS doesn’t have such a feature, and I couldn’t find anything in the (extensive) list of plugins that would do it for me. I needed to write my own.
I could have written a YOURLS plugin. Or I could have written a stack of code in Ruby, PHP, Javascript or
some other language to bridge these systems. But as I switched over my shortlink subdomain s.danq.me to its new home at danq.link, another idea came to me. I
have direct database access to YOURLS (and the table schema is super simple) and the command-line MariaDB client can output XML… could I simply write an XML
Transformation to convert database output directly into a valid RSS feed? Let’s give it a go!
I wrote a script like this and put it in my crontab:
mysql --xml yourls -e \ "SELECT keyword, url, title, DATE_FORMAT(timestamp, '%a, %d %b %Y %T') AS pubdate FROM yourls_url ORDER BY timestamp DESC LIMIT 30" \ | xsltproc template.xslt - \ | xmllint --format - \ > output.rss.xml
The first part of that command connects to the yourls database, sets the output format to XML, and executes an
SQL statement to extract the most-recent 30 shortlinks. The DATE_FORMAT function is used to mould the datetime into
something approximating the RFC-822 standard for datetimes as required by
RSS. The output produced looks something like this:
<?xml version="1.0"?> <resultset statement="SELECT keyword, url, title, timestamp FROM yourls_url ORDER BY timestamp DESC LIMIT 30" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <row> <field name="keyword">VV</field> <field name="url">https://webdevbev.co.uk/blog/06-2021/perfect-is-the-enemy-of-good.html</field> <field name="title"> Perfect is the enemy of good || Web Dev Bev</field> <field name="timestamp">2021-09-26 17:38:32</field> </row> <row> <field name="keyword">VU</field> <field name="url">https://webdevlaw.uk/2021/01/30/why-generation-x-will-save-the-web/</field> <field name="title">Why Generation X will save the web Hi, Im Heather Burns</field> <field name="timestamp">2021-09-26 17:38:26</field> </row> <!-- ... etc. ... --> </resultset>
We don’t see this, though. It’s piped directly into the second part of the command, which uses xsltproc to apply an XSLT to it. I was concerned that my XSLT
experience would be super rusty as I haven’t actually written any since working for my former employer SmartData back in around 2005! Back then, my coworker Alex and I spent many hours doing XML
backflips to implement a system that converted complex data outputs into PDF files via an XSL-FO intermediary.
I needn’t have worried, though. Firstly: it turns out I remember a lot more than I thought from that project a decade and a half ago! But secondly, this conversion from MySQL/MariaDB
XML output to RSS turned out to be pretty painless. Here’s the
template.xslt I ended up making:
<?xml version="1.0"?> <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"> <xsl:template match="resultset"> <rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"> <channel> <title>Dan's Short Links</title> <description>Links shortened by Dan using danq.link</description> <link> [ MY RSS FEED URL ] </link> <atom:link href=" [ MY RSS FEED URL ] " rel="self" type="application/rss+xml" /> <lastBuildDate><xsl:value-of select="row/field[@name='pubdate']" /> UTC</lastBuildDate> <pubDate><xsl:value-of select="row/field[@name='pubdate']" /> UTC</pubDate> <ttl>1800</ttl> <xsl:for-each select="row"> <item> <title><xsl:value-of select="field[@name='title']" /></title> <link><xsl:value-of select="field[@name='url']" /></link> <guid>https://danq.link/<xsl:value-of select="field[@name='keyword']" /></guid> <pubDate><xsl:value-of select="field[@name='pubdate']" /> UTC</pubDate> </item> </xsl:for-each> </channel> </rss> </xsl:template> </xsl:stylesheet>
That uses the first (i.e. most-recent) shortlink’s timestamp as the feed’s pubDate, which makes sense: unless you’re going back and modifying links there’s no more-recent
changes than the creation date of the most-recent shortlink. Then it loops through the returned rows and creates an <item> for each; simple!
The final step in my command runs the output through xmllint to prettify it. That’s not strictly necessary, but it was useful while debugging and as the whole command takes
milliseconds to run once every quarter hour or so I’m not concerned about the overhead. Using these native binaries (plus a little configuration), chained together with pipes, had
already resulted in way faster performance (with less code) than if I’d implemented something using a scripting language, and the result is a reasonably elegant “scratch your
own itch”-type solution to the only outstanding barrier that was keeping me on S.2.
All that remained for me to do was set up a symlink so that the resulting output.rss.xml was accessible, over the web, to my RSS reader. I hope that next time I’m tempted to write a script to solve a problem like this I’ll remember that sometimes a chain of piped *nix
utilities can provide me a slicker, cleaner, and faster solution.
Update: Right as I finished writing this blog post I discovered that somebody had already solved this problem using PHP code added to YOURLS; it’s just not packaged as a plugin so I didn’t see it earlier! Whether or not I use this alternate approach or stick to what I’ve got, the process of implementing this YOURLS-database ➡ XML ➡ XSLT ➡ RSS chain was fun and informative.
This checkin to GC9EZ55 Beam Approach Training reflects a geocaching.com log entry. See more of Dan's cache logs.
Dropped in to check on this cache while out for a cycle nearby. Both the first stage puzzle object and the cache container are in place and healthy.
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British motorists driving outside the UK must now remove old-style GB stickers or cover them up.
Instead they should display a UK sticker or have the UK identifier on their number plate.
The UK government guidance has been in place since Tuesday 28 September.
…
With the replacement of “GB” stickers with “UK” ones, I’ll soon be able to add another joke to my list of jokes that aged badly. I first read this in a joke book when I was a kid:
A young man gets his first car and his younger sister comes to look at it. “What’s this ‘L’ sticker for?” she asks.
“It stands for ‘Learning’,” replies man, “Because I’m still having driving lessons.”
Some time later, after he’s passed his test, the man is preparing to take a trip to France with his friends. His sister points to a sticker on his car. “Does this ‘GB’ mean you’re ‘Getting Better’?”
My @FreshRSS installation is the first, last, and sometimes only place I go on the Internet. When a site doesn’t have a feed but I wish it did, I add one using middleware (e.g. danq.me/far-side-rss).
Here’s to the next 20 years of my #RSS addiction.
This checkin to GC944X7 Pop! Bang! Crack! Goes the Christmas Cracker reflects a geocaching.com log entry. See more of Dan's cache logs.
The second of the caches in this series that I found in between errands, this afternoon, was probably the easiest, because the hiding place reminds me distinctly of one of my own hides! This one, though, enjoys some excellent Christmas theming, for which a FP is due. TFTC!
This checkin to GC93YF2 O Christmas Tree reflects a geocaching.com log entry. See more of Dan's cache logs.
I’d picked this one out as an essential for this afternoon’s “between jobs” hunt, because it completes my Solar System Wonders set. How pleased I was to find that through this cache a tree is properly – albeit sparsely – decorated. Thanks for this, my third and final cache of the day. I’ll be back to finish the series next time I’m around here with time to spare, I’m sure!
This checkin to GC93W4C Twelve Days of Caching reflects a geocaching.com log entry. See more of Dan's cache logs.
Having “solved” all the puzzles some time ago I’m picking away at finding the caches in this series a few at a time, starting the other week, every time I happen to be passing nearby. I felt a little overlooked by nearby windows this drizzly afternoon but I needn’t have engaged my stealth skills: the coordinates were spot on and I soon had the cache in my hand. TFTC.
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In his latest video, Andrew provides a highly-accessible and slick explanation of all of the arguments against what3words that I’ve been making for years, plus a couple more besides.
Arguments that he makes that closely parallel my own include that what3words addresses are (a) often semantically-ambiguous, (b) potentially offensive, (c) untranslatable (and their English words, used by non-English speakers, exaggerates problem (a)), and (d) based on an aggressively-guarded proprietary algorithm. We’re of the same mind, there. I’ll absolutely be using this video to concisely explain my stance in future.
Andrew goes on to point out two further faults with the system, which don’t often appear among my arguments against it:
The first is that its lack of a vertical component and of a mechanism for narrowing-down location more-specifically makes it unsuitable for one of its stated purposes of improving addressing in parts of the developing world. While I do agree that what3words is a bad choice for use as this kind of addressing system, my reasoning is different, and I don’t entirely agree with his. I don’t believe that what3words are actually arguing that their system should be used alone to address a letter. Even in those cases where a given 3m × 3m square can be used to point to a single building’s entryway, a single building rarely contains one person! At a minimum, a “what3words”-powered postal address is likely to specify the name of the addressee who’s expected to be found there. It also may require additional data impossible to encode in any standardisable format, and adding a vertical component doesn’t solve this either: e.g. care-of addresses, numbered letterboxes, unconventional floor numbers (e.g. in tunnels or skybridges), door colours, or even maps drawn from memory onto envelopes have been used in addressed mail in some parts of the world and at some times. I’m not sure it’s fair to claim that what3words fails here because every other attempt at a universal system would too.
Similarly, I don’t think it’s necessarily relevant for him to make his observation that geological movements result in impermanence in what3words addresses. Not only is this a limitation of global positioning in general, it’s also a fundamentally unsolvable problem: any addressable “thing” is capable or movement both with and independent of the part of the Earth to which it’s considered attached. If a building is extended in one direction and the other end demolished, or remodelling moves its front door, or a shipwreck is split into two by erosion against the seafloor, or two office buildings become joined by a central new lobby between them, these all result in changes to the positional “address” of that thing! Even systems designed specifically to improve the addressability of these kinds of items fail us: e.g. conventional postal addresses change as streets are renamed, properties renamed or renumbered, or the boundaries of settlements and postcode areas shift. So again: while changes to the world underlying an addressing model are a problem… they’re not a problem unique to what3words, nor one that they claim to solve.
One of what3words’ claimed strengths is that it’s unambiguous because sequential geographic areas do not use sequential words, so ///happy.adults.hand is nowhere near
///happy.adults.face. That kind of feature is theoretically great for rescue operations because it means that you’re likely to spot if I’m giving you a location that’s in
completely the wrong country, whereas the difference between 51.385, -1.6745 and 51.335, -1.6745, which could easily result from a transcription error, are an awkward 4 miles away. Unfortunately, as Andrew
demonstrates, what3words introduces a different kind of ambiguity instead, so it doesn’t really do a great job of solving the problem.
And sequential or at least localised areas are actually good for some things, such as e.g. addressing mail! If I’ve just delivered mail to 123 East Street and my next stop is 256 East Street then (depending on a variety of factors) I probably know which direction to go in, approximately how far, and possibly even what side of the road it’ll be on!
That’s one of the reasons I’m far more of a fan of the Open Location Code, popularised by Google as Plus Codes. It’s got many great features, including variable resolution (you can give a short code, or just the beginning of a code, to specify a larger area, or increase the length of the code to specify any arbitrary level of two-dimensional precision), sequential locality (similar-looking codes are geographically-closer), and it’s based on an open standard so it’s at lower risk of abuse and exploitation and likely has greater longevity than what3words. That’s probably why it’s in use for addresses in Kolkata, India and rural Utah. Because they don’t use English-language words, Open Location Codes are dramatically more-accessible to people all over the world.
If you want to reduce ambiguity in Open Location Codes (to meet the needs of rescue services, for example), it’d be simple to extend the standard with a check digit. Open Location Codes use a base-20 alphabet selected to reduce written ambiguity (e.g. there’s no letter O nor number 0), so if you really wanted to add this feature you could just use a base-20 modification of the Luhn algorithm (now unencumbered by patents) to add a check digit, after a predetermined character at the end of the code (e.g. a slash). Check digits are a well-established way to ensure that an identifier was correctly received e.g. over a bad telephone connection, which is exactly why we use them for things like credit card numbers already.
Basically: anything but what3words would be great.