July 06, 2013

My holiday week

or, A geek at play

So there I was, working on my syllabi. One of my courses, new to Longwood but familiar to many of my Knox alumni, is a survey of various areas and, as such, doesn't have a single good textbook. In the past I'd posted a bunch of Wikipedia links as "reading", but was never quite satisfied with that solution; this time round I thought I'd try posting reading lists for several textbooks which students would be able to either borrow from other students (e.g. those who'd taken upper-level courses in AI or databases) or else read them in the lab (where I'd put older editions of my own).

I started building it as a plain old HTML page, and I wasn't very far in before it started feeling very clunky, with me having to re-type a lot of boilerplate stuff. Modifying things or adding details was getting more difficult. In short, it was dumb to do this by hand (and exceptionally so as a computer scientist). Designing simple databases to store this sort of thing is, in fact, one of the skills I teach in this very course! So I set aside the work at hand in order to develop the database.

It didn't take me long to work out an E-R diagram for the database I would need (and, to be honest, working on the first few pieces by hand was helpful for informing me on the structure of the data); I once again appreciated how useful the basic "draw a bubble diagram" tactic is at organising data. Having devised a data description that met my own approval, I translated it into a corresponding set of relational tables (another skill I teach in this course---how convenient!). Of course, I now needed to devise a front end, both to enter the data and, eventually, to convert it into a form to present it on the web to the students, that being the original goal. I could quickly whip out a program that would do so and function adequately, but I'd have to run it by hand to do updates and the output would, in any case, look a bit Web 1.0. It occurred to me that this was the perfect opportunity to learn one of the web front-end technologies that I've been meaning to pick up for years---it's nearly impossible to learn a new language or tech unless you have a project at hand to write in it, and here I had one that was useful, important, and yet fairly small. A perfect first project. So I set aside the work at hand in order to pick up Ruby on Rails.

Step one on that was to install Ruby, and the Rails extensions; I tried to do it through the package installer on our department's server, but ran into some conflicts---and the server software will be upgraded in the next few weeks so I didn't want to muck with it. I ran into similar problems on my own (office) desktop machine, though, and I thought it might be a version issue. So I set aside the work at hand in order to upgrade to Xubuntu 13.04 (from 12.04).

This was nontrivial, as with the latest version of the distribution, they no longer can fit the installer on a CD, and I had no DVD blanks. It occurred to me to try the over-the-net upgrade, which was suboptimal because I would have to go by way of the intermediate version (12.10), but I tried it anyway and it seemed to work... until after the computer rebooted it completely failed to respond to the keyboard or mouse. They were fine if I booted from an old boot CD, though, so I took that opportunity to, um, refresh my backups. Then, I had to go buy DVD blanks after all, and burn a copy of the 13.04 boot DVD (on a classroom machine, because mine was booted from a CD, meaning I couldn't use the drive to do anything else!), and install from that. It worked! Success!

Back to Rails---the web frontend I plan to learn so that I can build the database I'm working on so I can display my reading assignments for my course in the fall. It turns out that all that intermediate stuff didn't help, and the package install failed with exactly the same messages as before. (Note: the time was not wasted! I now have an upgraded system, and fresh data backups.) Further investigation showed that the preferred way of installing is not to go through the standard package systems but instead to use a Ruby-specific version manager. Which does seem generally superior but completely does not work with tcsh... so that required some working around. But in the end I got Ruby, and Rails, installed. And at the top of the Rails tutorial it suggested that the learning curve would be "steep" if you didn't learn Ruby itself first. So I set aside the work at hand in order to learn Ruby.

That wasn't very hard---I'd seen pieces of it before, and I was able to race through an intro guide because I already had some pretty strong cognitive hooks to hang things on: "oh, that's a lambda", "ah, default values for the hash table", and so on. I wrote an OO word frequency counter and lost count of the number of times I'd try something a bit complicated ("if I were designing the language it'd work like this...") and it Just Worked. So it went pretty fast. Success!

Back to Rails---the web frontend I plan to learn so that I can build the database I'm working on so I can display my reading assignments for my course in the fall. There's a fairly detailed tutorial that works through all the features of Rails you'll need, and it's well-organised to (mostly) hit details one at a time. It was particularly fun, because after the first few sections I was able to see the object of the next section and make my own attempt at implementation based on what I'd learned so far, thus identifying A) what I did already know, B) things I thought I was supposed to know but was still shaky on, and C) the New Thing that simply hadn't been covered yet and was about to be introduced (although in a couple cases I was able to make a well-educated guess about that part, too :). Basically, having a good model of metacognition helped me structure the process to learn it quickly and well. There were definitely a few places that had unclear prose (and a few outright typoes), though. There was a note on the page that they accepted fixes to the docs, and before I moved on I wanted to make some notes about what to update. So I set aside the work at hand in order to jot down some notes about documentation improvements.

That's a little cheeky, if you think about it, since I literally started learning Rails today but was planning to tell them how to fix their documentation. But, hey, open source! And I do have, um, a reserve of knowledge about related topics. :) The way they recommended submitting suggestions was simply to fork the project on github, make changes, and then submit a pull request---all of which I understand in principle but hadn't ever really gotten around to doing (in part because I haven't really done a lot with open source since before github days). I'd work on that later, after actually doing the database I'm theoretically still working on, here. As I was taking notes for changes, though, I realised I wouldn't be able to remember what I was talking about if I waited. Also, nothing like a simple set of small changes to A) jump back into open source work, and B) get around to learning github. So... you may see where this is going... I set aside the work at hand in order to figure out github.

Which, ok, was dead simple. (I kind of knew it would be.) First of all, they have the cleanest, simplest signup process I've seen in a long time. And right off the first page is a clear set of instructions on how to get started. I got git installed locally, followed instructions to get a local clone of the rails distribution, and picked the simplest of my noted doc edits to implement. Committed the result locally, pushed the change to github, and after a bit of hunting about for the button to initiate a pull request, did so. Mere minutes later the request got approved, so now I'm technically a contributor to the Rails project. :) Success!

Back to the rest of the documentation changes, which I still wanted to enter before building the database I'm working on so I can display my reading assignments for my course in the fall. Interestingly, I found that in the development version on github, a few of the typoes had been fixed, but quite a few problems hadn't been; and at least one issue was "fixed" incorrectly. So I put together a few commits of (most of) the rest of the issues, and made another pull request. Success!

And back to... actually working on the database, ultimately so I can display my reading assignments for my course in the fall. Well, tomorrow.

By one measure, I haven't gotten anything done this week. But by another, I've gotten a ton done. And by any measure, I've been immeasurably geeky this week. :)

"Freedom is kind of a hobby with me, and I have disposable income that I'll spend to find out how to get people more of it." --Penn Jillette

Posted by blahedo at 3:20am on 6 Jul 2013
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