Jsmap is a project mainly written in JAVASCRIPT and RUBY, based on the MIT license.
Just a simple browser-based IF-MAP client built on ifmap.js
jsmap is a super-simple (and kind of manual) IF-MAP client implementation that runs in the browser. You can point and click to build requests and see a log of server responses. It's based on ifmap.js so IF-MAP subscriptions are not yet supported. A basic Sinatra application is used to proxy requests.
For a description of IF-MAP see the specification and other documentation at ifmapdev.com/documentation.
If you already have all that, then clone this repo and...
$ cd jsmap
$ ruby jsmap.rb
Point your browser to localhost:4567. Put in a MAP server url and hit 'start'. Then build requests and hit 'submit' to send them. Server responses are logged in the 'message log' pane.