title: AWS SNS not sending Subscription Confirmation
body: <p>I have setup AWS SNS setup with a topic say 'A'. I'm doing a subscribe to this SNS topic using Http (tried both manually using AWS console online and using Java Code). All I get is 'pending confirmation' in both cases. However SNS does not send the initial 'SubscriptionConfirmation' to the provided Url.</p>
  
  <p>Note that my endpoint is ready to receive http POST notification. When I manually do a POST from my side I see my servlet processing those Json I send. For some reason I receive nothing from AWS SNS. </p>
  
  <p>Note that my http end point that I used for subscribe is public facing so SNS should have no issue reaching it.</p>
  
  <p>Any inputs is appreciated.</p>
  
  <p>Here is my subscribe function.</p>
  
  <pre><code>public String subscribe(String arn,String url) {
  
      if(arn == null || arn.isEmpty())
          arn = topicArn;
      SubscribeRequest subRequest = new SubscribeRequest(arn,"http",url);
      SubscribeResult  result = snsClient.subscribe(subRequest);
      //get request id for SubscribeRequest from SNS metadata
      if(result != null){
          LOGGER.info("SubscribeResult - " + result.toString());
      }
      LOGGER.info("SubscribeRequest - " + snsClient.getCachedResponseMetadata(subRequest));
      return result.toString();
  }
  </code></pre>