Ok now that you added a few details in your first comment (you should edit the question and add these), I think I can answer what you are after.
var http = require('http')
var port = process.env.PORT || 1337;
var get_nosql_data = function(callback){
// do whatever it is here you need to get the data back
// and format it into a json object. pseudocode follows.
// error handling is also needed here, but not relevant to the answer
var db = require('db');
db.getData('some query', function(res){
var data = { name: res.entity[4], class: res.entityclass[4], address: res.entityaddrss[4] };
callback(data);
});
}
http.createServer(function(req, res) {
get_nosql_data(function(data){
res.writeHead(200, { 'Content-Type': 'application/json' });
res.end(JSON.stringify(data));
});
}).listen(port);
As long as you sub in the database values for the placeholder strings I have there, you should be up and running. This also should align with what azure already has set up for you.
Related, I would highly recommend checking out express - this will make your life a lot easier writing node web apps.