Fruddled Gruntbugglies

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  • Wrote an iCalendar downloader

    Tonight I wrote my first app with the Calendar API. Basically I used the calendar.c demo code as a reference, and pulled out the pieces I needed to do a quick iCalendar download app. It worked without a hitch. With just a little more tweaking, I’ll have a command-line app I can use to fetch arbitrary date ranges in iCalendar format.

    The caveat: It’s very slow with date ranges of more than just a few days. I guess that’s to be expected, given the performance I’ve seen with iCalendar downloads from the GUI client. It does eventually come back, though. A one-month range took a few minutes to complete; I hate to think how long three years would take!

    Of course, I plan to run this unattended from cron, so in theory I don’t care how long it takes, even if it’s a couple hours. The question is, if I try to suck down a three-year range in one big chunk, will it fubar the calendar server? Obviously that would not be good. The other option would be to pick a manageable chunk, say a few months, and only download that much at a time. I could just run it in a loop until I get the full 3 years. Will have to play with this.

    The other puzzler here is, the Oracle Calendar GUI calendar lets me download in either of 2 formats: iCalendar or something it calls “vCalendar”. I’m not sure of the exact difference, but vCalendar is a lot faster to download. What’s the difference between the two, and is there a way of doing the vCalendar download from the API? I wonder if there are certain iCalendar fields that take significantly longer to process. If the vCalendar download omits those, that could speed things up significantly.

    I suppose the thing to do is generate both iCalendar and vCalendar dumps for a specific date range, and compare the differences between the two. That may shed some light on things.

  • Drilled my holes

    I got kinda lazy yesterday, and didn’t get too much done on the bedroom fan wiring project. But, I did get one step closer to running a new wire from the basement to the attic. I got holes drilled in the top and bottom plates, and verified that both holes hit the same stud cavity. Fishing the wire should be pretty easy at this point.

    Rules of thumb for anyone who wants to attempt this…

    1. Ensure that you own a ranch house. 🙂
    2. Tools of the trade: tape measure, stud finder, drill, 1/8″ x 12″ feeler bit, 5/8″ spade bit, flashlight.
    3. Find reference points in the basement and attic so that you can (somewhat accurately) pinpoint where to drill. Examples are: pipe penetrations, wire penetrations, ducts, etc.
    4. Locate the wall studs, and pick your drilling spots so that you don’t hit the top (or bottom) of a vertical wall stud.
    5. Measure, measure, measure! Can’t stress this enough.
    6. Drill a pilot hole first to make sure you hit an open stud cavity. I use a 1/8″ x 12″ bit for this. After drilling, leave the bit in the hole. Then go upstairs/downstairs and make sure the bit is not sticking through the ceiling/floor!
    7. Assuming everything looks good, use a 5/8″ spade bit to enlarge the hole. When drilling downwards from the attic, make sure the bit is TIGHT in the chuck.
    8. Once you have drilled both holes, put a flashlight over the hole in the attic. Adjust the light for a focused (not diffuse) beam. Go down to the basement. Turn the lights off, look up into the hole, and make sure you can see the beam.

    Next: Let’s fish some wire..

  • Wiring fun

    So, I’m doing a bit of rewiring in our spare bedroom, soon to become my 3-year-old’s new room. The previous owners put up a ceiling fan. Problem is, they didn’t bother to install an approved box. It’s one of those lovely nail-to-the-underside-of-the-studs metal bar jobbies. Rather than sit around twiddling my thumbs until the fan comes crashing down, I’m putting a new box in with a proper brace. Along the way, I’m replacing the wall switch, a fan/light control that has (putting it nicely) seen better days.

    Well, nothing is ever that easy. The new fan control is slightly deeper than the old one. The power feeds through the wall box. There are 3 cables coming into the box: A 14-2 BX feed, a 14-3 BX carrying switched, unswitched and neutral to the ceiling box, and a 14-2 romex that someone added at a later date, to carry switched power to the fan (separate from the lights). So, we’ve got 3 cables and a grand total of 5 wirenuts (3 for the switch, 1 for neutral, and 1 to cap off the unused wire in the romex cable). Short story: I can’t fit everything in the box with the deeper switch.

    I want to use this switch. I’ve got 2 other identical ones elsewhere in the house. So, looks like I need to do some rewiring.

    I suppose I could replace the box. Nothing I haven’t done before. But, these boxes are holy hell to get out of the wall, without destroying the wall (plaster over gypsum board, or “rock lath” as it was called back in the day). No, I think I’ll rewire things and take the wall box out of the circuit, and make it a simple switch loop. Then I can cut it down to a single 14/3 cable going to the box, with a hot and two switched lines, 1 for the fan and 1 for the lights. Then it’ll fit.

    So, I’ll just find a wire in the attic that’s ahead of the switch box in the circuit, cut it, and route it directly to the ceiling box, right? Sure, in theory. Problem is, there are no wires in the attic that are ahead of the switch box. The switch box IS the feed from the basement to the attic. Time for plan B. Looks like I’ll need to run a new wire from the basement to the attic. This will require me to break out my wire fishing skills. Now, having wired my own security system, I’ve done my share of fishing. However I’ve never run a wire straight from the basement, through a stud cavity, and into the attic (this is a rancher, BTW. Unfinished attic on top, drop-ceiling basement on bottom. If you’re into wiring, ranchers rock). Seems like it should be easy in theory. I guess I’ll find out. This should be fun! More later.

  • Legacy CorporateTime API

    It appears that Oracle has totally dropped support for legacy CorporateTime servers in its recent SDK releases. I found some API documentation for the old CAPI_ functions, and as I mentioned before, some of them do appear to show up in the shared libraries. However, try as I might, I couldn’t reference any of the functions using the 10.1.1 libraries. The fact that none of them are prototyped in ctapi.h is also kind of telling. Looks like I won’t be getting any joy out of the 10.1.1 SDK. Could it be that Oracle dropped support so that more people would buy their new, expensive Collaboration Suite? Naaaah.

    However, I won’t give up that easily. I have Google. I plugged CAPI_Connect into Google, sifted through a few pages of results, and lo and behold, I found a site that had the entire 2.0 CorporateTime SDK, circa 2002, for Linux/i686!!! After glancing over my shoulder to make sure Oracle’s lawyers weren’t looking, I grabbed it.

    The SDK includes some example code, calendar.c, which connects to the server and allows interaction through a text-driven menu system. It built painlessly using the supplied Makefile. The next challenge was figuring out how to use it to log in. To make a long story short:

    1. First prompt: Hit return (no config file)
    2. Second prompt (name of calendar server): Enter calendar.umbc.edu:5730
    3. Third prompt (ACE mechanism): Enter 2. It seems to work fine without specifying an ACE mechanism.
    4. Fourth prompt (user or Sysop): Enter 1 to authenticate as a user.
    5. Fifth prompt (username): This was the tricky part to figure out. Enter ?/S=lastname/G=firstname/. In my case I used ?/S=riddle/G=paul/. Obviously patterned after the LDAP attributes, surname and givenName.
    6. Sixth prompt: Enter password.

    Once I figured out the proper incantations, it logged me into the calendar server! I tried out a few menu options. Data seems to come through in iCalendar format, which is what I want.

    This is great, it looks like I’ll be able to automate the export/massage/publish process as I had originally hoped.

    More later…

  • The ongoing Oracle Calendar saga

    Well, my initial efforts to use the Oracle Calendar SDK have been a resounding failure. I got everything installed, and was able to compile a “hello world” type program. However it appears that our calendar server is too old and crusty to work with the newer set of API functions, all of which have the prefix CSDK_. Apparently I need to use the old CorporateTime API, with functions that begin with CAPI_. Now, when I run nm * in the SDK library directory, it turns up a bunch of these functions, but I’m not sure they’re actually what I want, and I don’t have any documentation or sample code. I’ll search around, and give this one more shot, but I’m beginning to resign myself to the fact that this is going to have to be a partially-manual process, at least until we upgrade our calendar server.

    On the same front, I started looking at what it would take to create my own .ics file which I could subscribe to with iCal. I started by creating a dummy calendar in iCal, publishing it, copying the published .ics file into /tmp on my linux box, and then unpublishing the file in iCal (which deletes it off the WebDAV server). I then edited the .ics file in /tmp, changed the name, copied it file back to the web server, and successfully subscribed to it with iCal. Apple sticks a GUID field, among other things, into its published .ics files, and I’m not sure how I’d generate one from scratch, so I’ll just use this file as a template and I’ll be able to build a .ics file that iCal will be happy with. So, making progress here.

  • Oracle Calendar API Revisited

    Well.. I’ve managed to track down the Oracle Calendar SDK libraries for Linux. They’re included with the Oracle Collaboration Suite distribution, which I had originally thought only included libraries for the Mac. I did a little more digging and found this post on Oracle’s Calendar SDK message board. It turns out I need to run the installer and let it do an “official” install of the stuff. A bit convoluted given that all I need is a couple libraries and include files, but if it works…

    Here’s what I did:

    1. Downloaded the Oracle Collaboration Suite distribution (version 10g) from Oracle’s web site. It came as a 3.8-gig multipart compressed tar archive (thank God for Internet2)! After running the script to assemble the parts, I ended up with a file called OCS_101200.tar.gz.
    2. I’m not interested in everything in the tar file, just the calendar stuff. This is all in a directory called calendar_standalone. So, I untarred just that directory: tar xzvf OCS_101200.tar.gz calendar_standalone.
    3. I ran the installation script, runInstaller -ignoreSysPrereqs. The option tells the installer to keep running even though I’m not running one of Oracle’s pre-approved flavors of Linux.
    4. Walk through the menus, select the SDK, and follow the directions.

    After doing this, I ended up with the SDK (along with 300 megs of other kruft) installed in my home directory under a directory called product.

    Haven’t played around with it yet, but hopefully I can write something to do a simple event extract. If that works, I can write an automated script that extracts the data, massages it, and posts it as an iCal subscription. Stick it in cron to run nightly, and I’ve got my ultimate solution for Oracle Calendar integration. Wish me luck!

  • Missing Sync

    Well, as promised, I sprung $40 for The Missing Sync for Palm OS. I’ve installed it, set up sync with iCal and Address Book, and tried out the internet connection sharing feature. My initial impressions are good. Setup was painless. The iCal sync seems to work very well. The initial sync resulted in some duplicate calendar entries, but I think that’s because it was also pulling in my data from Palm Desktop. Once I deleted the duplicate data and got rid of the old Palm Desktop conduits, it worked great. As for the internet connection sharing, I doubt I’ll get much use out of it, but it works without a hitch.

    Missing Sync also includes an app that allows you to mount the SD card on the Mac desktop as an external volume. As I don’t yet have an SD card, I haven’t been able to try this out. I’m curious as to how it works. The documentation does not reveal many details. I’m hoping it emulates the USB storage standard, which would let me mount it on my Linux boxes as well. I’d like to be able to use the Palm as sort of a “poor man’s jump drive.” Again, I may not end up using it much, but I can try it out and see if it’s useful to me, or if I’d be better served with a “dedicated” USB jump drive.

    If it turns out that it doesn’t emulate USB storage, I can try out a product called Card Export II which advertises this functionality. It’s only $15 and I can download a fully functional trial version. But I’m hoping Missing Sync will do it for me.

    Next up.. I think I’m going to rework my Oracle Calendar intergration a bit. I’m going to write a Perl script to take the exported Oracle Calendar data (in vCal format), tweak it a bit for all-day events and holidays, and write it out in iCalendar format. Then I can just post the resulting iCalendar file on my web site, and subscribe to it with iCal. That way I don’t have to import it into iCal, which is a cumbersome process. We’ll see how it goes.

  • Phase One Calendar Plan

    It turns out, from my readings on the net, that iCal is a little limited with regards to publishing remote calendars and subscribing to them. You can either publish, or subscribe, but not both. That knocks iCal down a few pegs in my book, but it still seems to be the best option going for Palm synchronization, so I’m still going to build my initial calendaring solution around it. I won’t have all the functionality that I want, but it will be a good start.

    Incidentally, after my initial experimentation with Sunbird, I went back and read more about it. It turns out the version I was using, version 0.3alpha, is based on a total code rewrite and is actually less stable than its predecessor, version 0.2. I tried 0.2 out, and it doesn’t seem to suffer from the crashing problems I had with 0.3alpha. In fact, I can subscribe to and edit a remote WebDAV calendar just fine. iCal cannot do this (presumably because Apple wants to sell me a .mac membership to get this functionality). This, coupled with the fact that Sunbird works on Mac, Windows and Linux, makes me lean towards Sunbird as my ultimate Calendaring solution. However, as Sunbird does not have Palm sync support yet, I’m still stuck with iCal for the time being. So here’s what I’m going to do:

    1. Shell out the $40 for the Missing Sync product, to get tightly integrated Palm sync support for iCal. Hope the product works as well as advertised.
    2. Load all of my calendar data into iCal (export data out of Oracle Calendar and merge any local changes that I put into Palm Desktop)
    3. Publish all of my iCal calendars to my WebDAV server so I can view them with PHP iCalendar. Set up autopublish so they stay up to date.
    4. Try out the Oracle Calendar SDK. It would be nice to have a command line tool to export the data out of Oracle Calendar and automatically generate a .ics file that I can subscribe to with iCal.

    This will give me most of the functionality I’m after. I’ll be able to view, but not edit, the published calendars with PHP iCalendar or Sunbird. To edit them I’ll either need to use iCal on my laptop, or my Palm. Not perfect, but livable.

  • Fun with the National Student Clearinghouse

    Can I just say that I hate configuring passthrough authentication to outsourced sites on remote web servers?

    Rule 1: The company’s step-by-step setup instructions will not apply to your particular system configuration.
    Rule 2: It never works the first time.
    Rule 3: See rule 2.
    Rule 4: Debugging is impossible, because the error logs are on the remote site.

    It’s kind of like playing pin-the-tail-on-the-donkey: Put on blindfold, spin around a few times, try some stuff, and maybe you can get it to work. If not, call the rep. The rep is invariably non-technical and will have to pass the request on to a developer. The developer may or may not get back to you with useful info. Or maybe an error log. Or something. Then, you try again.

    Oh, and I forgot….
    Rule 5: Once you eventually do get it working, it will work for awhile, then break at the most inconvenient time possible, when the vendor decides to make some change to the remote site without telling anyone. Thus, it becomes a perpetual maintenance-hassle-waiting-to-happen that hangs over your head for, well, forever.

    I just, finally, got the passthrough authentication to work with the National Student Clearinghouse. Basically, their stuff works like this: Post several magic variables to their web server. Server sends back a form that includes an encrypted token. Form uses javascript to auto-post itself back to NSC web server, which brings up the student’s clearinghouse view.

    To make a long story short: It’s very picky about the HTTP_REFERER. We gave them the URL of our development server ahead of time. In the initial request, the referrer string that the script sends must begin with the URL we provided to them. Fine, I can use LWP::UserAgent to post the initial request, and set the referrer to whatever I want. I was still missing one piece though: In the second request (the auto-post form which is sent to the browser), the referrer must exactly match the referrer that I sent in the first request. Of course, NSC’s documentation conveniently doesn’t mention this.

    Example: If I give them ‘http://devel.umbc.edu’ as the development URL, then my initial referrer must begin with that. I can send ‘http://devel.umbc.edu/cgi-bin/blah.pl’ and it will accept that. On the second request, I have to send it exact the same referrer string as I did in the first request, or it won’t accept it, even if it matches the development URL. Got that?

    I probably made this harder on myself than it needed to be, by trying to get cute and fudge the referrer header from a URL other than the development URL I gave them. But it’s a bit annoying to have to jump through these hoops to make the thing happy about the referrer, given that it’s a really bad idea to rely on the referrer for any kind of security purposes in the first place.

    Oh well, let’s hope I don’t have to do this again for awhile.

  • Initial Impressions of Sunbird

    Just spent a bit of time playing around with Sunbird. I would call it “not quite ready for prime time.” It’s got a nice interface. I was able to subscribe to my iCal-published calendar without a hitch. It can auto-reload remote calendars on startup. I can also create local calendars and publish them successfully. However, the publishing support seems to be kind of a work-in-progress. When I publish a new calendar, it doesn’t remember its URL. I have to re-type it every time I publish. When I try to modify a remote calendar that I subscribed to, it crashes. There appears to be no support for auto-publishing as entries are made.

    I’ll keep an eye on Sunbird, but it looks like it’s not quite ready for day-in day-out use. I expect it’ll get there eventually though.