Google AJAX Feed API

Google this week announced the release of the Google AJAX Feed API. What is it? It's a JavaScript Library that lets you mashup RSS and Atom feeds entirely on the client, thus no need for server-side coding. In addition, one of the useful core features is that it can automatically map XML attributes to a JSON result format. To get a sense of what it can do, one of their example mashups has been added to our listings: the Google AJAX Tune Bar that lets you add iTunes RSS feeds to any page.

If you're familiar with JavaScript programming you'll note that typically this sort of client-side mashup would have some limitations due to browser security constraints restricting data to only come from the same server a given page was delivered. But Google works-around this by having their servers act as a proxy cache for all Feed requests made via the API. Which leads to a couple of other implications: "The AJAX Feed API, like Google Reader and the Google personalized homepage, caches individual entries within feeds and reconstructs feeds based on those entries. Consequently, feeds from the AJAX Feed API may not reflect the exact XML file from the URL you request. In many cases, you can request more entries from the AJAX Feed API than are currently available in the live feed." It is also interesting that we're seeing more JavaScript-based APIs from Google, including the AJAX Search API and the ever-popular Google Maps API. We'll probably see more in the future given that they've introduced a new base url of google.com/jsapi and a generalized JavaScript API load process: "Loading the API requires two steps because Google is moving to a new model of loading AJAX APIs to make it easier to include multiple Google APIs on your pages. Subscribe to the Google AJAX APIs Blog for announcements as we start rolling out this new AJAX API loading mechanism." This is one of those very useful but somewhat subtle APIs that has more power than may be initially apparent.

Be sure to read the next Feeds article: 53 Feeds APIs: Google Ajax Feeds, Superfeedr and Feedzilla