VersionManagementServlet.java

package fr.inria.atlanmod.collaboro.web.servlets;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import com.google.gson.Gson;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;

import fr.inria.atlanmod.collaboro.backend.CollaboroBackendFactory;
import fr.inria.atlanmod.collaboro.history.User;

@WebServlet(description = "Exposes the current version being used", urlPatterns = { "/versionManagement" })
public class VersionManagementServlet extends AbstractCollaboroServlet {
	private static final long serialVersionUID = 52L;

	@Override
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		addResponseOptions(response);

		// Checking the user is logged
		if(!isLogged(request)) {
			response.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
			return;
		}
		HttpSession session = request.getSession(false);
		User historyUser = (User) session.getAttribute("user");
		String dsl = (String) session.getAttribute("dsl");

		response.setContentType("application/json");
		PrintWriter out = response.getWriter();

		JsonObject jsonResponse = new JsonObject();
		String version = String.valueOf(CollaboroBackendFactory.getBackend(dsl, historyUser.getId()).getVersionTracked());
		jsonResponse.addProperty("version", version);

		out.print(jsonResponse.toString());
	}

	@Override
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		addResponseOptions(response);


		// Checking the user is logged
		if(!isLogged(request)) {
			response.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
			return;
		}
		HttpSession session = request.getSession(false);
		User historyUser = (User) session.getAttribute("user");
		String dsl = (String) session.getAttribute("dsl");

		// Getting the parameters from the request
		StringBuffer jb = new StringBuffer();
		String line = null;
		try {
			BufferedReader reader = request.getReader();
			while ((line = reader.readLine()) != null)
				jb.append(line);
		} catch (Exception e) {
			throw new ServletException("There was an error reading the parameters");
		}

		// Parsing the parameters
		Gson gson = new Gson();
		JsonParser parser = new JsonParser();
		JsonObject actionJsonObject = (JsonObject) parser.parse(jb.toString());
		String action = actionJsonObject.get("action").getAsString();

		if(action.equals("next")) {
			CollaboroBackendFactory.getBackend(dsl, historyUser.getId()).nextVersion();
		} else if (action.equals("previous")) {
			CollaboroBackendFactory.getBackend(dsl, historyUser.getId()).previousVersion();
		} else if (action.equals("create")) {
			CollaboroBackendFactory.getBackend(dsl, historyUser.getId()).createVersion();
		}

		response.setContentType("application/json");
		PrintWriter out = response.getWriter();

		JsonObject jsonResponse = new JsonObject();
		String version = String.valueOf(CollaboroBackendFactory.getBackend(dsl, historyUser.getId()).getVersionTracked());
		jsonResponse.addProperty("version", version);

		out.print(jsonResponse.toString());
	}

	@Override
	protected void doOptions(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {
		addResponseOptions(response);
	}

}