This plugin allows for non-OJS applications to make requests for data via HTTP requests to your journal and get JSON-formatted responses. The primary purpose for this is to integrate journal information (journal metadata, articles, announcements, etc) in your non-OJS CMS/web app.
This code is hosted on https://github.com/mcrider/rest
. I encourage others to fork the code and add additional functionality to the plugin (send me a pull request and I'll pull it in). There are a few things that I'd like to see added to this plugin, see the README.