Sample function that can be used to POST to the hub whenever your feed changes. The cfg object is something that has all the appropriate params depending on which environment you are on e.g. dev | staging | production etc

pubsubhubbub_post.js

function pubsubhubub_post(post_url, callback) {

  var payload = { hostname: cfg.hub,
    method: 'POST',
    headers: {'Content-Type': 'application/x-www-form-urlencoded'}
  }

  var pubsubhubub_request = https.request(payload, function(pubsubhubub_response) {
    //dunno y, but this no-op is needed here !!!
    pubsubhubub_response.on('data', function(chunk) { 
      console.log('BODY: ' + chunk); 
    });

    //redundant?
    pubsubhubub_response.on('close', function() {
      console.log('received close event after sending pubsub request with status code ' + pubsubhubub_response.statusCode)
      callback();
    });

    //this needs to be here for sure...
    pubsubhubub_response.on('end', function() {
      console.log('received end event after sending pubsub request with status code ' + pubsubhubub_response.statusCode)
      callback();
    });
  });

  pubsubhubub_request.on('error', function(e) {
    console.log('error during pubsubhubub_request...')
    console.error(e);
  });

  pubsubhubub_request.write('hub.mode=publish&hub.url=' + cfg.transportRequire + '://' + cfg.apiHost + '/feeds/rss2');
  pubsubhubub_request.end();

}