org.loklak.api.iot.YahiHazeServlet.java Source code

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Here is the source code for org.loklak.api.iot.YahiHazeServlet.java

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/**
 *  Yahi Haze Servlet
 *  Copyright 11.08.2016 by Sudheesh Singanamalla, @sudheesh001
 *
 *  This library 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 2.1 of the License, or (at your option) any later version.
 *  
 *  This library 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.
 *  
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program in the file lgpl21.txt
 *  If not, see <http://www.gnu.org/licenses/>.
 */

package org.loklak.api.iot;

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

import java.io.IOException;
import java.io.PrintWriter;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.charset.Charset;
import java.io.Reader;

import java.net.*;
import org.json.JSONArray;
import org.json.JSONException;
import org.loklak.server.Query;
import org.loklak.http.RemoteAccess;

public class YahiHazeServlet extends HttpServlet {

    private static String readAll(Reader rd) throws IOException {
        StringBuilder sb = new StringBuilder();
        int cp;
        while ((cp = rd.read()) != -1) {
            sb.append((char) cp);
        }
        return sb.toString();
    }

    public static JSONArray readJsonFromUrl(String url) throws IOException, JSONException {
        InputStream is = new URL(url).openStream();
        try {
            BufferedReader rd = new BufferedReader(new InputStreamReader(is, Charset.forName("UTF-8")));
            String jsonText = readAll(rd);
            JSONArray json = new JSONArray(jsonText);
            return json;
        } finally {
            is.close();
        }
    }

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

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        Query post = RemoteAccess.evaluate(request);

        // manage DoS
        if (post.isDoS_blackout()) {
            response.sendError(503, "your request frequency is too high");
            return;
        }

        String yahiURL = "http://yahi-map-data.rolandturner.com/yahi-map-data.json";
        JSONArray json = readJsonFromUrl(yahiURL);

        PrintWriter sos = response.getWriter();
        sos.print(json.toString(2));
        sos.println();
    }

}