Bad things don’t always come in threes. For my MythTV setup, four bad things all happened at once. First was that the governments of the Australian states that run Daylight Savings Time (DST) decided to jump on the energy-saving bandwagon and change the end-time for DST this year. Second was that the OzTivo folks changed the API for connecting to their program guide data, and closed the old API interface on the same weekend that DST was originally due to finish. Third, for some reason that I’m still investigating, my run-an-emerge-world-at-least-every-fortnight MythTV backend had an old timezone-data package, so any times it handled that should have still been DST weren’t. Fourth, Shepherd isn’t quite as smart as I thought it was, and I didn’t find out until too late…
Let me get something straight: Shepherd is the bees-knees of EPG grabbers for Australian MythTV users. If you’re a MythTV user in .au and not running Shepherd, stop reading this right now and go and update your system to use it–you’ll be glad you did. If I had just looked at some of the output it has been generating since OzTivo announced it’s changes, most of the agro I’ve suffered the last few hours would have been avoided.
In a nutshell, Shepherd is a “meta-grabber”. It includes code that can get program data from a dozen or so sources, and keeps looking up sources until it fills your listings with data goodness. It automatically updates these individual source grabbers as well, so you should never need to worry about its up-to-date-ness (more on that later though). It also fetches extra program data from IMDB and TVDB, and can even automatically grab station icons for you. Highly, highly recommended.
I could see that some of my EPG data was coming from OzTivo because I had seen the notes that they had put in the program data advising of the API change. The weird thing I saw was that for a program I was recording in the same timeslot each day, sometimes the message would be there and other times not. While I thought that this was a little strange, I figured that the OzTivo folks were just being overly cautious and trusted Shepherd to do all the updates it needed.
Then, ever since Sunday morning when the southern states *didn’t* switch back from DST, I’ve had recording times out by an hour–programs trying to record an hour early. So as I mentioned, I had ye-olde timezone data on the backend, which can’t have helped depending on the data source (although I’m trying to work out if this actually is a contributor as I would have thought it would send the recordings an hour late… plus, others who have confirmed their timezone data have had the same problems). For a couple of programs, I actually had double entries: one an hour too early, then a second one at the right time. This was weird, and I still can’t explain it!
A manual run of mythfilldatabase showed why I was getting the repeated OzTivo API messages. Shepherd had downloaded the updated grabber alright, but the new version has a Perl dependency that wasn’t satisfied and it couldn’t run. Rather than bail out, Shepherd elected just to keep running with the old grabber. Given the circumstances, I’m still deciding how I feel about that. :-
So once I was confident that the grabbers were working okay again, I decided to get the EPG straight. I remembered that mythfilldatabase will not replace any existing data it thinks is valid, which is why only data post-April-5-or-so looked nice again. So, with a mailing list post or two as encouragement, I truncated (database-admin-speak for “deleted all the data from”) the “program” and “programrating” fields in the mythconverg database and ran mythfilldatabase. After about 20 minutes, voila, fixed guide data!
So now I’m thinking of how I can alert myself to a problem with Shepherd. I used to just check the result of the last mythfilldatabase run through Information Centre or mythweb, but since Shepherd ends cleanly so does mythfilldatabase. Looks like I might have to come up with something hackish to look for Perl runtime errors in the mythfilldatabase log and do a Nagios passive service check or something… Sigh, as if I needed another little project to keep me busy… 🙂
Crossed Wires 