No callback on http request

Ups. I forgot to call req.end() when I created the test code for the GET request. I'm sorry for the confusion. So the following is working too now:

var options = { host: "http://www.google.com" };
var req = require("http").request(options, function(res)  {
        console.log("status: " + res.statusCode);
});
req.end(); // <=== was missing

But I still have some issues with the post call not ending. I think its because of the Mandrill API. The following sample code (POST req. to Requestbin) is working. The console prints the status code (200) after the request:

Serial1.setup(9600, { rx: B7, tx : B6 });
var wifi = require("ESP8266WiFi").connect(Serial1, function(err) {
  if (err) throw err;

  wifi.reset(function(err) {
    if (err) throw err;

    wifi.connect("<WIFI_SSID>", "<WIFI_PW>", function(err) {
      if (err) throw err;

      var content = JSON.stringify({ "msg": "Hello World!"});
      var options = { 
        host: "requestb.in", 
        port: 80, 
        path: "/1lxvhjs1", 
        method: "POST",
        headers: {
          "Content-Type": "application/json",
          "Content-Length": content.length
        }
      };
      var req = require("http").request(options, function(res)  {
          console.log("status: " + res.statusCode);
      });
      req.end(content);
      console.log('Request sent');
    });
  });
});

But when I do the same for the Mandrill API then the post request is not ending. Mandrill gets the request successfully but its seems that the Espruino is still waiting for a response:

Serial1.setup(9600, { rx: B7, tx : B6 });
var wifi = require("ESP8266WiFi").connect(Serial1, function(err) {
  if (err) throw err;

  wifi.reset(function(err) {
    if (err) throw err;

    wifi.connect("<WIFI_SSID>", "<WIFI_PW>", function(err) {
      if (err) throw err;
      
      var content = JSON.stringify({
        "key": "<MANDRILL_API_TOKEN>",
        "text": "This is a demo",
        "message": {
          "from_email": "example@mandrillapp.com",
          "to": [
            {
              "email": "<YOUR_EMAIL>",
              "type": "to"
            }
          ]
        }   
      });
      
      var options = { 
        host: "mandrillapp.com", 
        port: 80, 
        path: "/api/1.0/messages/send.json", 
        method: "POST",
        headers: {
          "Content-Type": "application/json",
          "Content-Length": content.length
        }
      };
      var req = require("http").request(options, function(res)  {
          console.log("status: " + res.statusCode);
      });
      req.end(content);
      console.log('Request sent');
    });
  });
});

I will try to investigate further. The same request (http & https) using a rest-client (Postman) is working correctly.