RXJS Chaining HTTP Calls

test.js

var http = require('http');
var RX = require('rx');
var request = require('request');

function get(url) {
  return RX.Observable.create(function(observer) {
    request(url, function(err, response, body) {
      if (err) {
        observer.onError(err);
        return;
      }
      observer.onNext(body);
      observer.onCompleted();
    });
  });
}

var source = get('http://httpbin.org/response-headers?count=0');

source
  .flatMap(function(body) {
    var obj = JSON.parse(body);
    return get('http://httpbin.org/response-headers?count=' + (parseInt(obj.count) + 1));
  })
  .flatMap(function(body) {
    var obj = JSON.parse(body);
    return get('http://httpbin.org/response-headers?count=' + (parseInt(obj.count) + 1));
  })
  .subscribe(function(body) { console.log(body) });

$ node test.js
{
  "Content-Length": "85",
  "Content-Type": "application/json",
  "count": "2"
}