This a repository full of all kinds of CouchDB + node.js goodies. This is not, however, a CouchDB client library.
To use the changes service:
cd changes node lib/service.js http://127.0.0.1:5984
This will start the service, look for any design documents, and start any change listeners you've defined. It will listen for 10 minutes before the HTTP keepalive expires.
It also checks every minute for new databases.
To define a new listener in your design doc:
{ ....
"changes":"var sys = require('sys');
var listener = function (change) {
sys.puts(JSON.stringify(change));
}
exports.listener = listener;",
}