YouTube has a very rich API that developers can call to get information about videos, post new videos, etc. Lots of Web sites use this API to do all kinds of wonderful things with YouTube videos.

So suppose you wanted to create a little application that works like an “all news” channel. But instead of just showing you CNN or MSNBC or whatever channel, it gathers news from lots of different channels and aggregates them. You then have an “all news all the time” channel that shows lots of different stories and will give you different viewpoints on the same story. Fox news, for example, will have a much different take on a story than will CNN or Al Jazeera.

The YouTube API gives you at least three ways to get new videos from a particular YouTube user. The simplest is to do a search and filter it by the YouTube author name. For example, this query:

http://gdata.youtube.com/feeds/api/videos?orderby=published&max-results=50&author=AssociatedPress&v=2

will give you the 50 most recent videos that were posted by the YouTube user “AssociatedPress”.

There’s a problem, though: the results in that feed will be delayed sometimes by more than 15 minutes. If I go to the AssociatedPress page on YouTube, I’ll often see videos there that do not show up in the feed returned by that query.

You can get up-to-date results by querying the individual user:

http://gdata.youtube.com/feeds/api/users/AssociatedPress/uploads?orderby=published&max-results=50&v=2

With that query, I’m able to get the most recent videos. Anything that shows up in the YouTube page for that user also shows up in the results I get back from the query.

But that’s just one source! If I want my news channel to get data from 50 different sources, I’d have to poll each one individually. That’s not terribly difficult, but it takes time. YouTube places limits on how often I can poll for videos. To keep from being throttled, you have to wait at least 15 seconds (a minute or longer if you don’t have a developer API key) between requests to the API. So getting the latest videos from all 50 sources will take somewhere between 12 and 50 minutes. Perhaps longer.

Not many sources post a video every 12 minutes, so there’s a lot of waste involved in polling all the time. And 50 minutes is way too long to wait for an update. 50 minutes? It’s not news anymore!

There is a third way. Go to your YouTube account and subscribe to the sources that you’re interested in. According to the documentation, you can subscribe to up to 2,000 different sources, and whenever you go to your subscriptions page you’ll see the most recent videos from those sources.

The really nice thing is that you can then do a single query to get the most recent videos from all your sources:

http://gdata.youtube.com/feeds/api/users/YourUserName/newsubscriptionvideos?orderby=published&max-results=50&v=2

Replace YourUserName in the URL above with the name of the user who subscribed to the sources you want to see.

With this, you can poll YouTube once every five minutes and get the most recent videos from all of your sources.

Another benefit is that you don’t have to change your program if you want to add or remove sources. All you have to do is log in to YouTube and edit your subscriptions.

Reduce your bandwidth usage and get your videos more timely. Sounds like a great deal to me.