Tracking a ship around the world

Jan 13, 2015 / 0 comments

I moved back from the California Bay Area to Belfast a while back and for various reasons it looks like I’m going to be here a while, so it made sense to have my belongings shipped over here. They haven’t quite arrived yet, and I’ll do another post about that process once they have, but I’ve been doing various tweets prefixed with “[shipping]” during the process. Various people I’ve spoken to (some who should know me better) thought this was happening manually. It wasn’t. If you care about how it was done, read on.

I’d been given details of the ship carrying my container, and searching for that turned up the excellent MarineTraffic which let me see the current location of the ship. Turns out ships broadcast their location using AIS and anyone with a receiver can see the info. Very cool, and I spent some time having a look at various bits of shipping around the UK out of interest. I also found the ship’s itinerary which give me some idea of where it would be calling and when. Step one was to start recording this data; it was time sensitive and I wanted to be able to see historical data. I took the easy route and set up a cron job to poll the location and itinerary on an hourly basis, and store the results. That meant I had the data over time, if my parsing turned out to miss something I could easily correct it, and that I wasn’t hammering Marine Traffic while writing the parsing code.

Next I wanted to parse the results, store them in a more manageable format than the HTML, and alert me when the ship docked somewhere or set off again. I’ve been trying to learn more Python rather than doing my default action of turning to Perl for these things, and this seemed like a simple enough project to try out. Beautiful Soup seemed to turn up top for HTML parsing in Python, so that formed the basis. Throwing the info into a database so I could do queries felt like the right move so I used SQLite - if this had been more than a one off I’d have considered looking at PostgreSQL and its GIS support. Finally Tweepy made it very easy to tweet from Python in about 4 lines of code. The whole thing weighed in at only 175 lines of code, mostly around pulling the info out of the HTML and then a little to deal with checking for state changes against the current status and the last piece of info in the database.

The pieces of information I chose to store were the time of the update (i.e. when the ship sent it, not when my script ran), reported area, reported state, the position + course, reported origin, reported destination and eta. The fact this is all in a database makes it very easy to do a few queries on the data.

How fast did the ship go?

sqlite> SELECT MAX(speed) FROM status;
MAX(speed)
21.9

What areas did it report?

sqlite> SELECT area FROM status GROUP BY area;
area
-
Atlantic North
California
Caribbean Sea
Celtic Sea
English Channel
Hudson River
Pacific North
Panama Canal

What statuses did we see?

sqlite> SELECT status FROM status GROUP BY status;
status
At Anchor
Moored
Stopped
Underway
Underway using Engine

Finally having hourly data lets me draw a map of where the ship went. The data isn’t complete, because the free AIS info depends on the ship being close enough to a receiving station. That means there were a few days in the North Atlantic without updates, for example. However there’s enough to give a good idea of just how well traveled my belongings are, and it gave me an excuse to play with OpenLayers.

(Apologies if the zoom buttons aren’t working for you here; I think I need to kick the CSS in some manner I haven’t quite figured out yet.)

Cup!

Jan 8, 2015 / 0 comments

I got a belated Christmas present today. Thanks Jo + Simon!

cup.jpg

Automatic inline signing for mutt with RT

Sep 18, 2014 / 0 comments

I spend a surprising amount of my time as part of keyring-maint telling people their requests are badly formed and asking them to fix them up so I can actually process them. The one that’s hardest to fault anyone on is that we require requests to be inline PGP signed (i.e. the same sort of output as you get with “gpg –clearsign”). That’s because RT does various pieces of unpacking[0] of MIME messages that mean that a PGP/MIME signatures that have passed through it are no longer verifiable. Daniel has pointed out that inline PGP is a bad idea and got as far as filing a request that RT handle PGP/MIME correctly (you need a login for that but there’s a generic read-only one that’s easy to figure out), but until that happens the requirement stands when dealing with Debian’s RT instance. So today I finally added the following lines to my .muttrc rather than having to remember to switch Mutt to inline signing for this one special case:

send-hook . "unset pgp_autoinline; unset pgp_autosign"
send-hook rt.debian.org "set pgp_autosign; set pgp_autoinline"

i.e. by default turn off auto inlined PGP signatures, but when emailing anything at rt.debian.org turn them on.

(Most of the other things I tell people to fix are covered by the replacing keys page; I advise anyone requesting a key replacement to read that page. There’s even a helpful example request template at the bottom.)

[0] RT sticks a header on the plain text portion of the mail, rather than adding a new plain text part for the header if there are multiple parts (this is something Mailman handles better). It will also re-encode received mail into UTF-8 which I can understand, but Mutt will by default try to find an 8 bit encoding that can handle the mail, because that’s more efficient, which tends to mean it picks latin1.

Update: Apparently Mutt in Jessie and beyond doesn’t have the pgp_autosign option; you want crypt_autosign instead (and maybe crypt_autopgp but that defaults to yes so unless you’ve configured your setup to do S/MIME by default you should be fine). Thanks to Luca Capello for pointing this out.

Back from DebConf 14

Sep 12, 2014 / 0 comments

I previously forgot to mention that I was planning to attend DebConf14, having missed DebConf13. This year the conference was held in Portland, OR. This is a city I’ve been to many times before, and enjoy, but I hadn’t spent any time wandering around its city centre as a pedestrian. I have to say I really prefer DebConfs that are held in middle of city. It always seems a bit of a shame to travel some distance to somewhere new and spend all the time there in a conference venue. Plus these days I have the added lure of going out and playing Ingress in a new location. DebConf14 didn’t disappoint in these respects; the location was super easy to get to from the airport via public transportation, all of the evening social events were within reasonable walking distance (I’ll tend to default to walking when possible) and the talk venue/accommodation were close to each other and various eating + drinking options. Throw in the fact at Portland managed to produce some excellent weather (modulo my Ingress session on the last Saturday morning, when rained on me) and it’s impossible to fault the physicalities of DebConf this year.

This year the conference format was a bit different; previous years have had a week long DebConf before the week of the conference itself. This year went for a 9 day talk schedule (Saturday -> Sunday) with various gaps of hacking time interspersed. I’ve found it hard to justify a full two weeks away in the past, so this setup worked a lot better from my viewpoint. Also I rarely go to DebConf with a predetermined list of things to do; the stuff I work on naturally falls out of talks I attend and informal discussions I have. Having hack time throughout the conference helped me avoid feeling I was having to trade off hacking vs talks.

Naturally enough a lot of my involvement at DebConf was around OpenPGP. Gunnar and I spent a fair bit of time getting Daniel up to speed with the keyring-maint team (Gunnar more than I, I’ll confess). We finally set a hard timeframe for freeing Debian of older 1024 bit keys. I was introduced to the Gnuk, which is a particularly interesting piece of open specification hardware with a completely Free software stack on top if it that implements the OpenPGP smartcard spec. Currently it’s limited to 2K keys but it’s hoped that 4K support can be added (and I ended up spending a couple of hours after the closing talk hacking on the source and seeing how much needs to change for 4K support, aided by the very patient Niibe). These are the sort of things that really benefit from the face time that DebConf offers to the Debian project. I’ve said it before, but I think it’s worth saying again: Debian is a bit like a huge telecommuting organization and it’s my opinion that any such organization should try and ensure its members actually spend some time together on a regular basis. It improves the ability to work remotely a hell of a lot if you can actually put a face to the entity you’re emailing / IRCing and have some sort of idea where they’re coming from because you’ve spent some time with them, whether that’s in talks or over dinner or just casual hallway chats.

For once I also found myself considering alternative employment while at DebConf and it was incredibly useful to be able to have various conversations with both old friends and people who were there with an eye on recruitment. Thanks to all those whose ears I bent about the subject (and more on the outcome in a future post). Thank you also to the many people involved with the organization of DebConf; I’ve been on the periphery a few times over the years and it’s given me a glimpse into the amount of hard work all of the volunteers (be they global team, local organizing team, video team or just random volunteers) put into making DebConf one of my must-attend yearly conferences. If you’re at all involved in Debian and haven’t attended I strongly urge you to do so - I’ll see you all next year at DebConf15 in Heidelberg!

Breaking up with America

Sep 6, 2014 / 0 comments

Back in January I changed jobs. This took me longer to decide to do than it should have. My US visa (an L-1B) was tied to the old job, and not transferable, so leaving the old job also meant leaving the US. That was hard to do; I’d had a mostly fun 3 and a half years in the SF Bay Area.

The new job had an office in Belfast, and HQ in the Bay Area. I went to work in Belfast, and got sent out to the US to meet coworkers and generally get up to speed. During that visit the company applied for an H-1B visa for me. This would have let me return to the US in October 2014 and start working in the US office; up until that point I’d have continued to work from Belfast. Unfortunately there were 172,500 applications for 85,000 available visas and mine was not selected for processing.

I’m disappointed by this. I’ve enjoyed my time in the US. I had a green card application in process, but after nearly 2 years it still hadn’t completed the initial hurdle of the labor certification stage (a combination of a number of factors, human, organizational and governmental). However the effort of returning to live here seems too great for the benefits gained. I can work for a US company with a non-US office and return on an L-1B after a year. And once again have to leave should I grow out of the job, or the job change in some way that doesn’t suit me, or the company hit problems and have to lay me off. Or I can try again for an H-1B next year, aiming for an October 2015 return, and hope that this time my application gets selected for processing.

Neither really appeals. Both involve putting things on hold in the hope longer terms pans out as I hope. And to be honest I’m bored of that. I’ve loved living in America, but I ended up spending at least 6 months longer in the job I left in January than I’d have done if I’d been freely able to change employer without having to change continent. So it seems the time has come to accept that America and I must part ways, sad as that is. Which is why I’m currently sitting in SFO waiting for a flight back to Belfast and for the first time in 5 years not having any idea when I might be back in the US.

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