title: Issue with Callback - OpenWhisk with Nodejs runtime
body: <p>I am developing a module in BlueMix OpenWHisk, where after a Cloudant feed change, I need to call an url, which would update few details on another platform. I am using nodejs runtime.</p>
  
  <p>The ask is for my action to wait, for the result of the POST request, to the url mentioned above. If the POST was successful, then I should execute the next sequence of events.</p>
  
  <p>Questions:</p>
  
  <ol>
  <li><p>How to wait for the result of the POST request, before the next sequence is executed ?</p></li>
  <li><p>Is it possible to wait and return the result of POST request.</p></li>
  </ol>
  
  <p>Positing my code</p>
  
  <pre><code>   /**
    *
    * main() will be invoked when you Run This Action
    *
    * @param OpenWhisk actions accept a single parameter, which must be a JSON object.
    *
    * @return The output of this action, which must be a JSON object.
    *
    */
  
  const util = require('util');
  var http = require('http');
  
  function main(params) {
  
      // Updated the status of the User
      params.status ="updated1";
  
      var options = {
                  host: "myhost.mybluemix.net",
                  path: "/addtoimc",
                  method: "POST",
                  headers: {
                      "Content-Type": "text/plain"
                  }
              };
  
  
        return {message : addtoIMC(options)};
  
  }
  
  function createRequest(data, options)
  {
  
      return http.request(options, function (res) {
              var responseString = "";
  
              res.on("data", function (data) {
                  responseString += data;
                  // save all the data from response
              });
              res.on("end", function () {
                  console.log("AAA" + responseString); 
              });
          });
  }
  
  
  
  function addtoIMC(options)
  {
      return new Promise(function(resolve, reject) {
              var req = createRequest("Hello",options);
              var reqBody = "post_data";
              req.write(reqBody);
              req.end();
  
          });
  }
  </code></pre>