source: src/main/java/geniusweb/runserver/RunNego.java@ 8

package geniusweb.runserver;

import java.io.IOException;
import java.util.logging.Level;
import java.util.stream.Collectors;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.fasterxml.jackson.databind.ObjectMapper;

import geniusweb.protocol.NegoSettings;
import tudelft.utilities.logging.ReportToLogger;
import tudelft.utilities.logging.Reporter;

/**
 * Contains incoming connection to run a Nego. runserver/runsession with the
 * JSON {@link NegoSettings} in the request header. After the session is
 * started, the new Nego ID is returned. This can be used to find back the log
 * files..
 */
@SuppressWarnings("serial")
public class RunNego extends HttpServlet {
        private final Reporter log;
        private final static ObjectMapper jackson = new ObjectMapper();

        public RunNego() {
                this(new ReportToLogger("runserver"));
        }

        public RunNego(Reporter logger) {
                super();
                this.log = logger;
        }

        /**
         * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
         *      response). Returns
         *      <ul>
         *      <li>URL with websocket address to contact the now running party.
         *      <li>SC_NOT_FOUND (404) if attempt is made to access non-running
         *      party.
         *      <li>SC_SERVICE_UNAVAILABLE (503) if there are no free slots to run
         *      the party.
         *      <li>SC_EXPECTATION_FAILED (417) if something else goes wrong during
         *      instantiating the party (then see logs for more details)
         *      </ul>
         */
        @Override
        protected void doGet(HttpServletRequest request,
                        HttpServletResponse response) throws ServletException, IOException {
                String reqstring = request.getReader().lines()
                                .collect(Collectors.joining());
                NegoSettings settings;
                try {
                        settings = jackson.readValue(reqstring, NegoSettings.class);
                } catch (IOException e) {
                        response.sendError(HttpServletResponse.SC_BAD_REQUEST,
                                        e.getMessage());
                        System.err.println("Run request failed " + reqstring);
                        e.printStackTrace(); // helpful for debugging run requests
                        return;
                }
                log.log(Level.INFO, "request to run Nego: " + settings);
                RunningNego session = new RunningNego(settings,
                                RunningNegotiationsRepo.instance(), log);
                session.start();
                // set content type to prevent some browsers
                // trying to parse this (eg as XML)
                response.setContentType("application/json");
                response.getWriter().append(session.getID());
        }

        /**
         * @see #doGet(HttpServletRequest, HttpServletResponse)
         */
        @Override
        protected void doPost(HttpServletRequest request,
                        HttpServletResponse response) throws ServletException, IOException {
                doGet(request, response);
        }

}