index.js

module.exports = CSTransport;

var Promise       = require('bluebird');
var HttpTransport = require('http-transport');
var jsonpClient   = require('jsonp-client');
var path          = require('path');
var urlUtil       = require('url');

function CSTransport()
{
  this.httpTransport = new HttpTransport();
}

CSTransport.prototype.get = function(url, params)
{
  if (isExternalRequest(url)) {
    return jsonpGet(url, params);
  }
  else {
    return this.httpTransport.get(url, params);
  }
};

function jsonpGet(url, params)
{
  url = path.join(url, urlUtil.format({ query: params }));
  url = addCallback(url);

  return new Promise(function(resolve, reject) {
    jsonpClient(url, function(err, data) {
      if (!err)
        resolve({ body: data });
      else
        reject(err);
    });
  });
}

function addCallback(url) {
  // The URL already has a callback
  if (url.match(/callback=[a-z]/i)) {
    return url;
  }
  return url + ('&callback=cb' + Math.random()).replace('.', '');
}

function isExternalRequest(url)
{
  return (url.indexOf('http') >= 0) ? true : false;
}