PLANET DAL CS

I've been doing some work recently on cobbler4j, a small Java library for interacting with Cobbler over XMLRPC based on the work done to integrate Cobbler into Spacewalk.

Right now the library basically allows you to open up a connection, and interact with the core object types (repos, distros, profiles, systems) as if they were actual Java objects. In the future this will likely grow to include other operations and background tasks. And as a required disclaimer, this is still very much a work in progress and should not be considered stable.

The cobbler4j wiki page covers most of the high level details on what it does and how to use it.

Here's a sample program:

import org.fedorahosted.cobbler.CobblerConnection;
import org.fedorahosted.cobbler.Finder;
import org.fedorahosted.cobbler.ObjectType;
import org.fedorahosted.cobbler.autogen.Distro;
import org.fedorahosted.cobbler.autogen.Profile;
 
import java.util.List;
import java.util.LinkedList;
 
public class Cobbler4jDemo {
 
    public static String DEMO_PROFILE = "demoprofile";
 
    public static void main(String [] args) {
 
        CobblerConnection xmlrpc = new CobblerConnection("http://192.168.1.1", "testing",
                "testing");
        Finder finder = Finder.getInstance();
        List<Distro> distros = (List<Distro>)finder.listItems(xmlrpc, 
                ObjectType.DISTRO);
        System.out.println("Distros list:");
        for (Distro d : distros) {
            System.out.println("   " + d.getName());
        }
        System.out.println();
        System.out.println();
 
        // Delete the demo profile if it got left laying around:
        Profile demoProfile = (Profile)finder.findItemByName(xmlrpc,
                ObjectType.PROFILE, DEMO_PROFILE);
        if (demoProfile != null) {
            System.out.println("Deleting profile: " + DEMO_PROFILE);
            demoProfile.remove();
            System.out.println();
            System.out.println();
        }
 
        // Create a demo profile, set the required properties:
        System.out.println("Creating profile: " + DEMO_PROFILE);
        demoProfile = new Profile(xmlrpc);
        demoProfile.setName(DEMO_PROFILE);
        demoProfile.setDistro("centos-5.3-i386");
        demoProfile.commit();
        System.out.println();
        System.out.println();
 
        System.out.println(DEMO_PROFILE + " settings:");
        System.out.println("   kickstart = " + demoProfile.getKickstart());
        System.out.println("   virt file size = " + demoProfile.getVirtFileSize());
        System.out.println("   Red Hat management key = " + demoProfile.getRedhatManagementKey());
        System.out.println();
        System.out.println();
 
        List<Profile> profiles = (List<Profile>)finder.listItems(xmlrpc, 
                ObjectType.PROFILE);
        System.out.println("Profile list:");
        for (Profile p : profiles) {
            System.out.println("   " + p.getName());
        }
        System.out.println();
        System.out.println();
 
        // Lookup our specific demo profile:
        demoProfile = (Profile)finder.findItemByName(xmlrpc, 
                ObjectType.PROFILE, DEMO_PROFILE);
 
    }
}

Some interesting things to note, firstly rather than maintain Java classes with a bevy of irritating getters/setters, Michael Dehaan started us down the path of auto-generating the Java classes from a template and the FIELDS metadata in the Cobbler Python code itself. (which describes each property on an object, it's type, and some other information) This posed some build problems early on but in the end it actually came out ok, and the build is relatively seamless with ant.

In the above example a couple magical things happen. The first relates to object creation, when creating the profile we specify only the bare minimum of information. If you were to do this from the cobbler CLI however your object would immediately have a number of other default settings applied. To replicate this behaviour after doing a commit on any cobbler object we immediately repoll the state from cobbler and update the object state internally for you.

Similarly another problem arises with Cobbler's notion of inheritance known as "blending". The implementation of this basically results in object properties being set to an inherit string constant if they're to use their parent object's value. This gets complicated however when you're auto-generating a Java class that expects a Boolean, but gets a String instead. Usually not a catastrophic problem in a dynamic language like Python, but Java is not so happy about it. To solve this we also maintain a hash of the "blended" properties as well which are obtained via a separate API call. Whenever we call a getter, and that object supports inheritance, and the property comes back as inherit, we instead return the value from the parent. This has the added benefit of not inadvertently setting parent values directly on the object itself whenever we do a commit.

So definitely a bit of magic going on but so far I haven't thought of situation where it would break down, and thus I'm content with it for now. There's some minimal overhead involved in the refresh calls but in local testing it's blazing fast, and likely not calls that will be used under heavy load. (as far as I can forsee)

While the bindings are definitely not yet considered stable, wheels are in motion and as always contributions would be welcome if anyone would like to participate. Special thanks to Partha Aji for his assistance, ideas, and contribution of the Finder class used for querying/listing objects.

November 19, 2009 06:35 PM

November 18, 2009 06:00 PM

November 10, 2009 11:43 PM

So in the H1N1 drama that’s sweeping the nation, we’re finding that those sick with respiratory illnesses and weakened immune systems are unable to get the H1N1 vaccine. Why is that? That’s because hockey teams have stepped up to the plate and proudly said, “Me First!”

The first ones to get busted doing this were the Calgary Flames. Someone in the Alberta health department ended up getting canned for this, though they won’t release any details so it’s hard to tell whether the right person got canned or not. Most Albertans have their blame sights set on their health minister as opposed to any employee of the system. The one thing lost in this story though is Alberta’s other hockey team, the Edmonton Oilers. Either they’re doing a top notch job of keeping their vaccinations quiet or they are massively pissed off right now. I mean seriously, what would it be like if all the NY Giants got shots but none of the NY Jets did? It’s pretty much the same comparison here.

I’ll admit it takes a lot more than a handful of healthy hockey players to screw things up for everyone. Thankfully there have been enough jerks to go around. I’ve already heard lots of first hand accounts of doctors bringing home vaccinations for their family and a bunch of friends and there’s the all too common jerks who went out early, lied about their medical conditions to pretend they had real health issues. That way those healthy individuals were able to get a vaccine way before those suckers with actual health problems who couldn’t go out and wait for four hours in a line outdoors.

I figure at this rate, another 4 or 5 days and we’ll have reached rampant cannibalism.

November 05, 2009 10:49 PM

I am hoping that the title of this post binds me to publishing this entry this year... it could very easily languish in my Drafts like many other well-intentioned blog posts. Afterall, the Vancouver Asian Film Festival starts today....

Today, we're going back to that comment made by our New York host that was just a fact of life for her but, for me, it might be the catalyst of enlightenment... of sorts. She had observed how Asian diaspora/pride/identity crisis is so pronounced where she now lives compared to twenty years of growing up Vancouver.

Now, what makes Vancouver so special? What makes the various big cities in North America different from each other? Other than the obvious that there are west coast cities like Vancouver, L.A., and San Francisco, and east (coast) cities like Toronto and New York, I am fascinated by why Vancouver, Seattle, and San Francisco aren't identical twins for our similar proximity to Asia compared to, oh, those cities way across the continent in the Eastern time zone.

We learned back in grade school how Canada roughly differs from the United States in that while the U.S. boasts of a melting pot (newcomers tend to assimilate after which you can all peacefully co-exist), Canada's multicultural picture ressembles more that of a mosaic (where differences are celebrated and maintained and overall, a coherent picture emerges). The reality, I find, is that mosaics are maintained in the big cities, American and Canadian, and melting pots occur in in the smaller cities... like in Halifax, where I grew up.

Continue reading....

November 05, 2009 08:34 AM

We always have a decent turnout for Halloween, somewhere around 150 trick-or-treaters. Last year, we decided to make a change though. We had always given out the regular stuff that most people give, small chocolates, cheezees (sp?), chips, etc… Some new health issues came to light for us and we started shifting how we eat and thought that we could do better for the kids at Halloween as well. Here’s the hard part. Kids don’t want to get fruit on Haloween. That’s a good way to get your house egged. I don’t know how easy it is to get egg off of brick, but I don’t ever want to find out. Besides, with the rampant paranoia that goes around this time of year, what parent would let their kid eat an apple or other unpackaged food. It’s just easier/safer to toss that stuff out since there’s so much in the kid’s bag anyways. So my wife found a great idea online; give them hot chocolate.

Now hot chocolate isn’t exactly on your traditional list of recommended foods for young people, but it’s a whole heck of a lot less bad for them than the chocolates we were handing out the year before. Since the boxes of hot chocolate come with 10 small packs in them, you can hand them out in individual sizes readily in a sealed, safe package. Last year we thought we’d give it a try and overall the kids seemed to like it a lot. We went for it again this year and I think the kids convinced us to stick with it from here on out. There were lots of kids who got it and turned excitedly to their parents to scream, “Mom/Dad, hot chocolate!” but one kid stood out. He arrived on our stairs with half a can of pop in one hand, clearly riding the sugar rush through his last bunch of houses. We gave him some hot chocolate, he looked up with great big saucer-sized eyes and half-shouted, “Best House!” and promptly ran off to ask his mother if they could have the hot chocolate tonight.

Halloween’s great fun in our neighbourhood. It’s nice and brief (about a 2 hour window), the kids are mostly young and their costumes are always great.

November 01, 2009 09:01 PM

Flight: $300 Rental car: $(paid for by work ) Dinner: $20 Tickets: $100 Shirts: $140 Sleep: 5.5 hours in the last two days Getting to see Metallica live last night in Toronto: you know it. I didn’t take pictures, but YouTube has tons of videos.

October 28, 2009 03:59 PM

I finally watched it. I bought the DVD a while ago as a buy 3 for $20 thing but never got around to actually watching it. I found it to be a decent movie, quite good for a superhero movie, but overall was just decent. What I absolutely loved though, was the mad scientist aspect of it all. I love, love, love to tinker/build. As soon as the movie ended, my wife turned to me and said, “You do know you can’t do that right?” I had to agree, but I mentioned that the power source is really the only major barrier to building most of that suit. She groaned.

Iron man 2 is coming next year. I can hardly wait : )

October 22, 2009 10:33 PM

Each year, the "release" of the VAFF (Vancouver Asian Film Festival) schedule is like mini-Christmas to me as I peruse the highly manageable list of films screening over the four-day festival. Each year, I identify at least two films I want to watch and for the past two years, I have managed to watch none during the festival run. Each year, I'm tempted to blather about how appreciative I am about living in a city that has an Asian Film Festival but I'll refrain and just tell you about the three (consecutive) film festival evenings I have committed to by having already purchased tickets.

White on Rice

If you didn't know it, there is something vaguely obscene-sounding from the expression "white on rice". Like possibly Asian fetish suggesting. It turns out "white on rice" means "all over something you like", for example,"When Krispy Kreme Donuts opened their first shop in Boston this summer, the locals were on it like white on rice."

I first heard of this movie through the series of articles about the movie written by Angry Asian Man since the movie has been making the film festival circuit this summer. Then it dawned on me that this "film festival darling" (my quotes) would be screened at my local Asian film festival--yay! I read only one article, one with the director, where I learned that (ahem, unlike the next movie), the script was written with no particular ethnicity in mind; however, since the movie portrays a family, when one main character was cast, the rest of the family needed to be consistent.

Continue reading....

October 21, 2009 01:30 PM

Well it would seem that at some point in the past, my tags were blown away and my database backups are a little sketchy. The ones I have are all post-tag-destruction. I was using Ultimate Tag Warrior and was getting set to make a move to the integrated tags in Wordpress when I noticed the issue.

Left with no real recourse, I’ve started adding tags to posts by hand. It’s going to take some time so the tag cloud isn’t going to be perfect for a while still. It’s a great reminder though to make sure that things are in order on your blog. It matters.

October 15, 2009 10:17 PM

With an image for the blog entry--for which I have no idea how much trouble I'm in--now I am ready to talk about it.

October 13, 2009 07:40 AM

The final part of my extra long weekend wrapped up with a day trip to Wakefield to take a ride on the Steam Train (www.steamtrain.ca). It was an enjoyable experience and we were blessed with a the lack of rain. I did notice with the limited amount of time we were able to spend before the [...]

October 13, 2009 01:55 AM

It’s tough to find fun games without forking out tons of money. I’m a pretty cheap guy and tend to wait until games are no longer cool and then buy them cheap. I haven’t played a current game since X-Wing Alliance. Over time I’ve picked up on a few open source projects that have become favourites of mine. In case you want to see what’s out there in the open source gaming community, check these out:

• Battle For Wesnoth (Tile/Turn based fun)
• FreeCiv (Civilization clone)
• UFO:Alien Invasion (XCOM clone)

If you’re a programmer, the great thing is that you can help out with these projects by contributing. None of these are “finished” nor do they really envision a finish line. So long as there are things that could make the game better and developers willing to pitch in, the projects will continue. Even if you’re not a programmer, at least give them a try because they’re fun

October 11, 2009 09:59 PM

a.k.a. "The race I nearly forgot was a race and thus nearly forgot to blog about it...."

October 05, 2009 02:04 AM

Montreal is in 1st place.

I’m always a little pessimistic, but this year there’s good cause. There are a lot of changes that happened over the off season and the early predictors aren’t great. One of them was a lean looking defensive core. Over two games we’ve seen Carey Price, our goalie face 81 shots. That’s a lot of shots. Price has been holding strong, but can’t be asked to do this night after night.

Then there’s the fact that the new guys really haven’t had to face the Montreal media yet. There’s a good reason that Montreal has done better on the road than at home over the lats bunch of years. It’s calm and peaceful on the road and you can focus on the game. In Montreal, it is literally a circus with every sneeze being analyzed to death. They’re out on a 5 game road trip to start the season. Two down, three to go. We’ll see what happens when the team rolls back into the most hostile hockey city in the world. Even if you’re the home team.

October 05, 2009 12:16 AM

October 01, 2009 07:24 PM

Yes, wyn is copping out a little (a lot) and posting the list that I fastidiously made after Joyce tweeted about Vancouver Magazine's recently released 2009 list of 101 foods to find yourself eating around the city. Because I like having yet another list to refer to... and that means there will be about one more year to make it through this list and last year's list until the next list, right??

Legend/Guide:
* Bolded -- I've been there and/or I've had that there!
* Italicized -- Haven't had it but I really think I will manage to try it... someday....

1. Prawn Crab Rolls - Pattaya Thai Restaurant (NW)
2. Mango Popsicle - T&T
3. Black Truffle Pizza - Market
4. Giant Oreo - Butter Baked Goods
5. Crispy Cauliflower - Nuba
6. Stuffed Rabbit Saddle - Bacchus at the Wedgewood
7. Jasmine Dragon Pearls - Granville Island Tea Company
8. Fricasse - Medina Cafe

Continue reading....

September 24, 2009 06:24 PM

When asked, I like to tell people that from primary to grade 8, I attended "The Convent" (it became a Sacred Heart School). And from grade 9 to graduation, I attended a grammar school. Because, you know, in the real world where private school alum are swamped by former public school kids, you have to focus their attention to your uniquely sheltered lifeview with monikers like "Catholic girls school" and pish-posh British-sounding "grammar school". Yup, although my ten-year non-reunion rolled around 4 years ago, I think the sheltered life still has some repercussions. Particularly, at times, I still gawk at the shenanigans people got up to during their high school years!

August 31, 2009 01:36 PM

August 28, 2009 02:58 PM

Born deep in the depths of the Spacewalk project, Tito is a build tool for RPM based projects using git. It is written in Python and Perl and distributed under the GPLv2. Originally this code lived directly in the Spacewalk git repository, but the functionality seemed like it may be useful enough to stand on it's own so we've decided to clean it up and release as a separate project.

Features

• Tag new releases with incremented RPM version or release.
• Auto-generate spec file changelog based on git history since last tag.
• Create reliable tar.gz's with consistent checksums from any tag.
• Build source and binary rpms off any tag.
• Build source and binary "test" rpms off most recently committed code.
• Build multiple source rpms with appropriate disttag's for submission to a Koji build system. (not yet documented)
• On a per-branch basis in git:
  • Maintain concurrent version streams.
  • Vary the way packages are built/tagged.
  • Report on any diffs or commits messages missing since last tag.
• Build packages off an "upstream" git repository, where modifications in the "downstream" git repository will be applied as a patch in the source rpm. (not yet documented)
• Manage all of the above for a git repository with many disjoint packages within it.

Download

tito 0.1.1 (2009-08-25)

tito-0.1.1.tar.gz
tito-0.1.1-1.fc11.src.rpm

Documentation

Please see the included README, available on the web at github.

Source Code

Also available on github.

Community

For feedback, help, or those looking to contribute please stop by #tito on Freenode.

You can email me at dgoodwin at rm-rf.ca. No mailing list at the time but if it looks like one will be useful I'll set something up.

August 26, 2009 02:23 AM

Disclaimer: There is no useful information here (unless you didn’t know you could negotiate at Futureshop). This is just a long explanation of my crappy personal shopping experience. I still like Futureshop. I’ll just never be able to go to the same one again thanks to scary dude … I’ve been in the market for a 52″ TV [...]

August 25, 2009 07:54 AM

Just in case we are not aware of it, Angry Asian Man takes it upon himself to alert you to the Asian contestants in some reality shows even when it is apparent he does not watch them himself (SYTYCD s05, SYTYCD s04). It's always interesting to me to note when there is an under- or overrepresentation of Asians in a competition compared to general demographics. And if they deserve it, I'll root for them staying in the competition as long as possible.

NPY and I rapidly gave up on watching So You Think You Can Dance (SYTYCD) Canada but we're sucked back in this year with what seems like better production and dancers, and the host is hitting her stride. We might potentially get overloaded with SYTYCD, and television in general, this fall when the American version starts a new season very quickly after wrapping up the last one....

This year we watched with great anticipating as the auditions continued and a Top 20 group of dancers was selected. The harrowing and physically demanding process whittled some 200 finalists down to the top ten guys and top ten girls... and there is Asian representation in each.

Continue reading....

August 24, 2009 01:40 PM

Silly me, I actually dream of carrying the Olympic torch during some part of the nation-wide relay later this year. I thought it would be super-nice to have a reason to go home in November as I had requested to run Lunenburg-Halifax or Halifax-Truro, assuming those are lower-demand regions. I signed up with RBC by filling out a brainlessly easy online form and then I knew I needed to increase my chances (up to two entries) by signing up through iCoke. I do not and will not drink Coke... or dark pop.

So it's kind of fitting that in order to make my little dream come true, I had to write a mini-essay (200-220 words in length) explaining how I "live Olympic on the Coke Side of Life." What does Coke embody anyhow? There were suggestions to write about "the positive impact you have had on yourself or others related to how you help the environment". The environment? I don't know about that. But I can re-iterate about running so here we go....

(Mind you, I don't expect at all to win a torch-bearing spot, period. Especially not with this POS I wrote over my lunch hour the day before the deadline. :P)

When I was in high school, I looked at cross-country club runners like they were crazy and rued the 50-metre dash requirement of the Canada Fitness Test. How, then, did I end up fifteen years later with four marathons and twenty other races under my belt?

August 22, 2009 08:59 AM

August 20, 2009 02:49 AM

August 17, 2009 01:36 PM

Lots of concerts in Halifax this summer, but I didn’t go to any of them, partly because of the $$$, and partly because I really didn’t care that much (although there’s an outside chance that I’ll be catching Metallica in concert in October, which would be pretty awesome). Tall ships were here, totally missed [...]

August 15, 2009 02:37 AM

So, while down in San Francisco, I picked up a touchatag rfid reader at Java One (had a really nice conversation with the developer to boot). Unfortunately, I haven’t gotten it working as of yet (Linux support is….. yeah and that is what I am running at home these days). But, I did have a really neat idea at the time involving rfid and inventory.

Basically, if you could tag your groceries with RFID tags and turn your cupboards into an RFID reader, you could have a running inventory of what if in your cupboards. Tie that into a web app, and you could access this inventory from say… your iPhone while at the grocery store. No more accidentally buying yet ANOTHER 1L tub of peanut butter when you already have one at home. Something similar to this has already been done here, which reminded me of my original idea.

Of course, currently tagging your foodstuffs with RFID now would be somewhat expensive, but the system can still technically be done using barcodes. As any Mac users might know, the web cam can be used as a barcode reader. Obviously, other web cams can become bar code readers as well. You could take a cheap netbook , mount it under your cupboards (assuming foodstuffs are kept in overhanging cupboards) and use it to scan in/out everything in your cupboard. Same effect achieved. Bonus in that you could use the laptop for other things in the kitchen, such as displaying recipes, listening to music, etc.

Thoughts?

August 12, 2009 04:22 PM

August 08, 2009 03:13 PM

I wanted to add my thoughts to the lackluster, non-existent debate* swirling around the July 16 episode of "So You Think You Can Dance" when ten dancers remained: five guys and five girls. The night before, to show off their talents in smaller groups, the girls performed a group number together and the guys did one later in the show. The girls' number was a sassy, athletic, graceful, exhilerating Bollywood number. The guys closed out the show with an acrobatic and athletic African dance routine. I fully enjoyed the Indian-style of dancing but was less than entirely impressed by the guys. The guys' routine seemed more random and I could feel myself yawning.

On Thursday nights all the remaining dancers perform together and we saw the curtain rise (so to speak) on a night-time set with a full red moon over some shadows evoking the rooftops of Japanese-style establishments. The routine was choreographed by the super husand-and-wife team of Wade and Amanda Robson and set to Janet Jackson's "So Much Betta".

Continue reading....

August 06, 2009 05:54 PM

August 04, 2009 02:14 PM