This is an extension of DJ Adams' excellent SheetAsJSON Google Apps Script, which provides a way to GET a published Google Spreadsheet as a JSON feed. This version allows generic filtering for terms, more specific control over which rows to parse, and correct MIME type for JSONP output.
The following parameters are required for the script to work.
https://script.google.com/macros/s/AKfycbzGvKKUIaqsMuCj7-A2YRhR-f7GZjl4kSxSN1YyLkS01_CfiyE/exec?
+ id=<spreadsheet key>
+ sheet=<sheet name on spreadsheet>