HCMC Blogs

Got some bugs with the progress bar worked out, and then started in on the AJAX stuff. Again, it took me a while to get used to the way JQuery does things -- it seems a bit more complicated than anyone would want -- but I finally got it to send data to a PHP page, retrieve a list of <option> elements, and dump them into two <select> elements. Then I did some testing across different browsers, using Japanese, to make sure the character encoding was round-tripping OK. There doesn't seem to be any problem with that.

The next stage is to write the db connector in PHP, so that simple table editing will be enabled.

Setting up rutabaga as a server also created a set of firewall rules that look like this:
Chain INPUT (policy ACCEPT)
target prot opt source destination
ACCEPT all -- anywhere anywhere
ACCEPT tcp -- anywhere anywhere tcp dpt:ssh
ACCEPT tcp -- anywhere anywhere tcp dpt:www
DROP all -- anywhere anywhere
LOG all -- anywhere anywhere limit: avg 5/min burst 5 LOG level debug prefix `iptables denied: '

Chain FORWARD (policy ACCEPT)
target prot opt source destination

Chain OUTPUT (policy ACCEPT)
target prot opt source destination

These rules effectively block all outgoing traffic. In my quest for knowledge I discovered that Hardy has a simplified CLI to iptables called ufw. Details here. It looks like it's as simple as this:
sudo ufw allow 80

With the new academic year and course descriptions, classlists, and a new student information management system to be navigated before the weekend, I'm intrigued by the question posted in the Digitaldigs blog: is teaching a creative profession?

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Found a useful progress bar component, and worked on combining it with the dialog component to create solid interface feedback for when AJAX events are taking place. Also worked around the Safari bug by browser-sniffing and disabling resizing. Annoying, but we can't fix Safari, and JQuery may fix the problem in the end.

Posting time spent on tech support for PhilWeb, some scanning for a faculty member, some admin with paycheques, and various other bits and pieces through the day.

Got a call from JJ to say the London Maps project had been down for a while. It turned out that both Francotoile and London were missing their eXist services, which were presumably not restarted after an outage. Got LM up and running quickly thanks to Corey, and then with some help from Greg, we got F going.

After a bit more work on interactivity code, I began doing some more testing across different browsers, and hit what looks like a major Safari bug -- a show-stopper for the GUI, really. If a <select> element is included in a resizable container, then you cannot select any of the options in Safari (tested on 3.1 on Windows and OSX). I've posted a report in the JQuery UI bugtracker and on their mailing list, so we'll see if anyone can suggest a workaround; meanwhile, I might have to disable resizing on Safari to get around this. That would be a real shame.

Link: http://chronicle.com/wiredcampus/article/3259/why-computer-aided-teaching-works-best-in-large-classes

From the Chronicle of Higher Education, a report of a working paper released last week by the National Bureau of Economic Research suggesting students seem most likely to benefit from computer-assisted instruction in large classes with frequent absences.

While the authors caution against drawing too many inferences from this single study, their evidence suggests that:

insofar as computer-assisted instruction is valuable, the scholars suggest, it is because it allows more individually tailored instruction in large, diverse classrooms where teachers find it hard to target each student with the appropriate level of work.

Today I finished the GUI layout, and did significant work on the resizing and cosmetic aspects. Virtually everything that needs to be resizable is now resizable, and the default setup is fairly attractive. I set up three dialog boxes using the JQuery dialog() component, and reworked all their interface graphics to change them from orange to a green that matches the rest of the interface. I started overriding some of the default Flora theme settings. I've also started coding some of the interface functionality (adding and deleting fields from one table in another, at the GUI level), and I'll get all that working smoothly before I write the db connectivity and all the AJAX stuff.

This is going a little more slowly than a site built without JQuery, because I have a lot to learn about JQuery, but it's going to be a lot more flexible and easily maintainable in the end. I think time spent on learning JQuery is well invested.

This morning, more joy with Lab B teacher station, which had been running and logged in all night. Attempting to log off proved fruitless -- the system presented the log off dialog box, but just did nothing when I clicked on the button, apart from dismissing the dialog box -- and it was impossible to shut it down either. My guess is that many users are simply giving up on this and leaving it logged on. I had to shut it down with the power button and restart it.