Question

I am working with google app engine task queue. Its my first time. I found a tutorial but having some problems. Following are two servlets i am using to check task queue:

 public class GAEJSignupSubscriberServlet extends HttpServlet {

   private static final Logger _logger = Logger.getLogger(GAEJSignupSubscriberServlet.class.getName());


public void doGet(HttpServletRequest req, HttpServletResponse resp)
        throws ServletException, IOException {


    resp.setContentType("text/plain");
    resp.getWriter().println("Hello, world");

    String strCallResult = "";
    resp.setContentType("text/plain");
    try {
        String strEmailId = req.getParameter("emailid");
        _logger.info("Got a Signup Subscriber Request for Email ID : " + strEmailId);
        //
        // PUT YOUR TASK CODE HERE
        //
        if(strEmailId.equals("mh")){
        System.out.println("email-id" + strEmailId);
        }
        strCallResult = "SUCCESS: Subscriber Signup";
        _logger.info(strCallResult);
        resp.getWriter().println(strCallResult);
        }
        catch (Exception ex) {
        strCallResult = "FAIL: Subscriber Signup : " + ex.getMessage();
        _logger.info(strCallResult);
        resp.getWriter().println(strCallResult);
        }
}
@Override
    public void doPost(HttpServletRequest req, HttpServletResponse resp)
       throws ServletException, IOException {
          doGet(req, resp);
    }

 }

second servlet is:

  public class GAEJCreateTaskServlet extends HttpServlet {

public void doGet(HttpServletRequest req, HttpServletResponse resp)
throws IOException {
    this.doPost(req, resp);
}

public void doGet(HttpServletRequest req, HttpServletResponse resp)
        throws IOException {
    resp.setContentType("text/plain");
    resp.getWriter().println("Hello, world");

    String strCallResult = "";
    resp.setContentType("text/plain");
    try {
        //Extract out the To, Subject and Body of the Email to be sent
        String strEmailId = req.getParameter("emailid");

        //Do validations here. Only basic ones i.e. cannot be null/empty

        if (strEmailId == null) throw new Exception("Email Id field cannot be empty.");

        //Trim the stuff
        strEmailId = strEmailId.trim();
        if (strEmailId.length() == 0) throw new Exception("Email Id field cannot be empty.");
        //Queue queue = QueueFactory.getDefaultQueue();
        Queue queue = QueueFactory.getQueue("subscription-queue");
        queue.add(TaskOptions.Builder.withUrl("/gaejsignupsubscriber").param("emailid",strEmailId));
        strCallResult = "Successfully created a Task in the Queue";
        resp.getWriter().println(strCallResult);
        }
        catch (Exception ex) {
        strCallResult = "Fail: " + ex.getMessage();
        resp.getWriter().println(strCallResult);
        }
}
    @Override
    public void doPost(HttpServletRequest req, HttpServletResponse resp)
       throws ServletException, IOException {
          doGet(req, resp);
    }

 }

I am invoking GAEJCreateTaskServlet with this URL:

 http://localhost:8080/gaejcreatetask?emailid=[e-mail]

now problem is when i invoke this url i see the output that task is created but in development console i can not see any task in the queue. If i remove doPost function from both servlets then i see the task in the queue but when i run it nothing happens and tasks remains there. Why is it happening so and how can i solve this problem. Thanks in advance.

Answer 1

Most likely you can’t see the task because it has already executed. Check your logs (the console in development, or the logging page on the admin console in production) to see what exception is being thrown by your task handler (if any) and fix it.