Using DSR to allow On-Demand JavaScript for RSS/ATOM feeds

It would be great to see data services provide a JavaScript version of their APIs to allow web developers that don't have (or want) server resources to implement data mashups. JavaScript APIs that can be used via HTML script elements allow for cross-domain data access without server intermediaries.

With the release of Tagneto 0.4.0 there is an update to the Dynamic Script Request (DSR) API, an API that makes On-Demand JavaScript via HTML script elements reliable and easy to use.

The API now uses a reserved callback function, window.onscriptload, and an event object passed to that method to communicate the success/error codes and the data associated with the response. Other browser events and the XMLHTTPRequest object were used to guide the names of the event properties.

These changes allow for data services that provide RSS/ATOM feeds (or any type of XML data feed) to provide a JavaScript response that is equivalent to the normal XML response without too much work (basically encode the XML as a JavaScript string, and put it in an event object that is passed to window.onscriptload).

The API document has more detail on how a RSS/ATOM feed might be provided as JavaScript in the Possible Applications section.

Tagneto 0.4.0 provides a Dsr.js helper script that implements the DSR API for use in a web page, and there is a DSR jar file that can be used in Java Servlet applications to send DSR responses.

Tagneto's home page uses the DSR JavaScript library and the DSR jar for the "Recent Blog Entries" section as a demonstration of the API and the implementation.