io.mapzone.arena.geocode.GeocodeServlet.java Source code

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Here is the source code for io.mapzone.arena.geocode.GeocodeServlet.java

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/*
 * polymap.org Copyright (C) 2016, the @authors. All rights reserved.
 *
 * This is free software; you can redistribute it and/or modify it under the terms of
 * the GNU Lesser General Public License as published by the Free Software
 * Foundation; either version 3.0 of the License, or (at your option) any later
 * version.
 *
 * This software is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
 */
package io.mapzone.arena.geocode;

import java.util.List;
import java.util.Locale;

import java.io.IOException;
import java.io.OutputStreamWriter;
import java.net.URLDecoder;

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

import org.json.JSONObject;
import org.json.JSONWriter;

import org.apache.commons.lang3.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.http.HttpStatus;

import org.polymap.core.runtime.event.EventManager;

/**
 * Servlet to expose the geocode service.
 * 
 * Parameters should be encoded with iso-8859-1
 *
 * @author Steffen Stundzig
 */
public class GeocodeServlet extends HttpServlet {

    private static Log log = LogFactory.getLog(GeocodeServlet.class);

    /** serialVersionUID */
    private static final long serialVersionUID = 1L;

    private final GeocodeService service;

    public GeocodeServlet(final GeocodeService service) {
        this.service = service;
    }

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        try {

            EventManager.instance().publish(new ServletRequestEvent(getServletContext(), req));

            if (req.getParameterMap().isEmpty()) {
                resp.sendError(400, "No parameters found! Please specify at least 'text'.");
                return;
            }

            GeocodeQuery query = extractQuery(req);

            // perform search
            List<Address> addresses = service.geocode(query);

            resp.setStatus(HttpStatus.SC_OK);
            resp.setContentType("application/json;charset=utf-8");
            handleCors(req, resp);

            // convert addresses to result json
            OutputStreamWriter outputStreamWriter = new OutputStreamWriter(resp.getOutputStream());
            JSONWriter writer = new JSONWriter(outputStreamWriter);
            writer.object();
            writer.key("results");
            writer.array();
            for (Address address : addresses) {
                writer.value(toJSON(address));
            }
            writer.endArray();
            writer.endObject();
            outputStreamWriter.flush();
            outputStreamWriter.close();
        } catch (Exception e) {
            e.printStackTrace();
            resp.sendError(HttpStatus.SC_INTERNAL_SERVER_ERROR, e.getMessage());
        }
    }

    private void handleCors(HttpServletRequest req, HttpServletResponse resp) {
        String origin = req.getHeader("Origin");
        resp.addHeader("Access-Control-Allow-Origin", StringUtils.isBlank(origin) ? "*" : origin);
        resp.addHeader("Access-Control-Allow-Headers", req.getHeader("Access-Control-Request-Headers"));
        resp.addHeader("Access-Control-Allow-Methods", "GET");
    }

    private GeocodeQuery extractQuery(HttpServletRequest req) throws Exception {
        GeocodeQuery query = new GeocodeQuery();
        // extract params
        if (!StringUtils.isBlank(req.getParameter("country"))) {
            query.country.set(new Locale("", req.getParameter("country")));
        }
        if (!StringUtils.isBlank(req.getParameter("targetLanguage"))) {
            query.targetLanguage.set(new Locale(req.getParameter("targetLanguage")));
        }
        if (!StringUtils.isBlank(req.getParameter("text"))) {
            query.text.set(URLDecoder.decode(req.getParameter("text"), "utf-8"));
        } else {
            if (!StringUtils.isBlank(req.getParameter("postalCode"))) {
                query.postalCode.set(URLDecoder.decode(req.getParameter("postalCode"), "utf-8"));
            }
            if (!StringUtils.isBlank(req.getParameter("city"))) {
                query.city.set(URLDecoder.decode(req.getParameter("city"), "utf-8"));
            }
            if (!StringUtils.isBlank(req.getParameter("street"))) {
                query.street.set(URLDecoder.decode(req.getParameter("street"), "utf-8"));
            }
            if (!StringUtils.isBlank(req.getParameter("houseNumber"))) {
                query.houseNumber.set(URLDecoder.decode(req.getParameter("houseNumber"), "utf-8"));
            }
        }
        return query;
    }

    private JSONObject toJSON(Address address) {
        JSONObject json = new JSONObject();
        if (!StringUtils.isBlank(address.id)) {
            json.put("id", address.id);
        }
        if (!StringUtils.isBlank(address.label)) {
            json.put("label", address.label);
        }
        if (!StringUtils.isBlank(address.country)) {
            json.put("country", address.country);
        }
        if (!StringUtils.isBlank(address.state)) {
            json.put("state", address.state);
        }
        if (!StringUtils.isBlank(address.county)) {
            json.put("county", address.county);
        }
        if (!StringUtils.isBlank(address.city)) {
            json.put("city", address.city);
        }
        if (!StringUtils.isBlank(address.district)) {
            json.put("district", address.district);
        }
        if (!StringUtils.isBlank(address.street)) {
            json.put("street", address.street);
        }
        if (!StringUtils.isBlank(address.houseNumber)) {
            json.put("houseNumber", address.houseNumber);
        }
        if (!StringUtils.isBlank(address.postalCode)) {
            json.put("postalCode", address.postalCode);
        }
        if (address.position != null) {
            JSONObject position = new JSONObject();
            json.put("position", position);
            position.put("longitude", address.position.getX());
            position.put("latitude", address.position.getY());
        }
        return json;
    }
}