Month: August 2009

America's Broken Laws

August 12, 2009 10:26 am

Do you remember Real Player? Huge in the late 1990s. They provided software for streaming audio/video over the Internet before Macromedia blew them out of the water with Flash. They've been quiet for a while, but recently they re-emerged with their latest product: RealDVD. It is software that allows you to make a backup of a DVD.

They knew that this was going to get them sued by the MPAA, and they were looking for the fight. As much as I (and millions of others) hated RealPlayer back in the 1990's I (and millions of others) have been on their side in this battle.

So what is the battle? DVDs are "protected" with the Content Scramble System (CSS). In 1999 DVD Jon gained his name by cracking this system; allowing anyone to access the data stored on DVDs without paying the fee required to get the code to decrypt the content. Yes, that's right. Any DVD player you've ever used; whether in your laptop, desktop, or connected to the tv; was only allowed to be produced after the manufacturer ponied up the cash for the license to legally decrypt the CSS and agreed to the demands that they wouldn't produce a product which allows the consumer to make a copy of the DVD.

So when DVD Jon reverse-engineered CSS, and let the cat out of the bag, the MPAA was not happy. Luckily for the MPAA they had already managed to pass the Digital Millennium Copyright Act (DMCA). Section 1201 (2) Says:

`(2) No person shall manufacture, import, offer to the public, provide, or otherwise traffic in any technology, product, service, device, component, or part thereof, that--
`(A) is primarily designed or produced for the purpose of circumventing a technological measure that effectively controls access to a work protected under this title;
`(B) has only limited commercially significant purpose or use other than to circumvent a technological measure that effectively controls access to a work protected under this title; or
`(C) is marketed by that person or another acting in concert with that person with that person's knowledge for use in circumventing a technological measure that effectively controls access to a work protected under this title.

In short: If there is any kind of copy-protection measure on a piece of media then it is illegal to access the content without paying the proper people for access (and since the people authorizing access won't authorize any use allowing duplication we have our problem).

DVD Jon's work is illegal under the DMCA. Fortunately for DVD Jon, he lives in Norway and the MPAA can't really do much about it. The bigger issue for the MPAA is that the code necessary to break the encryption on a DVD is so simple it can be written on a t-shirt. Not exactly a big hurdle for people that want to use it.

So why is this an argument at all in the first place? Something is illegal, so you shouldn't do it, right? Well, the problem is this little notion of Fair Use (also see the Electronic Frontier Foundation's FAQ). The Fair Use doctrine says you can make a personal back-up copy of content you own.

Fair Use says you can make a backup copy of any content you own, the DMCA says it's illegal to make that copy if the content has any type of copy-protection system in place. Take a guess which side wins in these arguments. I'll give you a hint, it's not us, the individual citizens of the country. If we want to make a back-up of The Fox and the Hound so that when the DVD gets all scratched and destroyed we don't have to buy it again, we can't.

This is the current state of the law in the United States. Absolutely ridiculous and inconsistent. The RealDVD case was decided today by U.S. District Judge Marilyn Hall Patel in San Francisco (ruled against Real). In her remarks she made this absurdity very clear:

So while it may well be fair use for an individual consumer to store a backup copy of a personally owned DVD on that individual’s computer, a federal law has nonetheless made it illegal to manufacture or traffic in a device or tool that permits a consumer to make such copies,

(For a complete article on the matter see Wired's Judge Rules DVD-Copying Software Is Illegal)

Django - Cronjobs Made Easy!

August 8, 2009 3:04 pm

For those that have no interest in reading about my nerd-ventures, you can stop reading this post now.

If you're still reading, don't say I didn't warn you.

As has been mentioned previously (mainly on my previous blog), I've been doing a fair bit of side project work using the Django Framework. Sadly, the out-of-the-box Django doesn't provide a solution for running cronjobs (for tasks that need to be run within the Django environment).

Since that's a fairly common requirement I didn't think it was going to be a big deal, but there wasn't a really solid solution out there. There are a few different attempts, but they each have some limitation. There's django-cron but that just skips over the native cron entirely, which I felt was a bit extreme. Cron can already do a good job of waking up and running a command, so duplicating that functionality doesn't seem necessary. It also self-declares that it is designed for frequent tasks (hourly or more frequently), which doesn't work for me. Tasks on the Board need to be able to run from a minute scale to a daily scale and beyond.

Then I found this guy's method, which works, but I'd like a little more integration. That way when developing apps the "go add cron job" isn't a separate step. I want the job information to right in with the rest of my app information. That way I can see what should be happening and when.

That's when I came across Django-Chronograph. This solution was 95% of what I wanted. It provides a nice interface to the system to monitor your jobs and view logs. It requires only a single crontab entry. It uses the iCalendar style of task declaration so you have total control of when your jobs run. However, it is limited to running commands through the Django Management system. I wanted something a little more programmatic. Such that I could just point at whatever function I wanted for my jobs.

So I took Django-Chronograph and started my modifications. The result is Django Cron Manager. Setup is very similar to using the Admin system. You call the cron_manager.autodiscover() function from your urls.py file. This goes out and inspect your installed apps and registers any Cron Jobs they declare. Then, using the guts of Django-Chronograph, it keeps track of these jobs in the database and monitors when they need to run.

I'm planning on posting all the code with an example at some point, but I'm going to try to get in touch with Weston (the guy who wrote Django-Chronograph) to see if he just wants to roll my changes into his system permanently. If you stumble upon this post and the changes aren't in Django-Chronograph, and I haven't provided any further information. Just leave a comment that you're interested in the code with a way to contact you and I'll get something to you.

*** Update ***
I've posted the code here: http://code.google.com/p/django-chronograph/issues/detail?id=15