org.opendatakit.aggregate.servlet.EnketoApiHandlerServlet.java Source code

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Here is the source code for org.opendatakit.aggregate.servlet.EnketoApiHandlerServlet.java

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/*
 * Copyright (C) 2013-2014 University of Washington
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package org.opendatakit.aggregate.servlet;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.DataOutputStream;
import java.net.HttpURLConnection;
import java.net.URL;

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

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.opendatakit.aggregate.ContextFactory;
import org.opendatakit.aggregate.constants.common.UIConsts;
import org.opendatakit.common.web.CallingContext;

public class EnketoApiHandlerServlet extends ServletUtilBase {

    private static final long serialVersionUID = 5811797423869654357L;
    private static final Log logger = LogFactory.getLog(AggregateHtmlServlet.class);

    public static final String ADDR = UIConsts.ENKETO_API_HANDLER_ADDR;
    private final String USER_AGENT = "Mozilla/5.0";
    private static final String RESPONSE_ERROR = "Please verify the Enketo Webform Integration settings on the Preferences tab and try again.";

    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String enketo_api_url = null;
        HttpURLConnection con = null;
        BufferedReader in = null;
        String message = null;
        String enketoURL = null;
        try {
            enketo_api_url = req.getParameter("enketo_api_url");
            String enketo_api_token = req.getParameter("enketo_api_token");
            String form_id = req.getParameter("form_id");

            CallingContext cc = ContextFactory.getCallingContext(this, req);
            String aggregate_server_url = cc.getSecureServerURL();

            enketo_api_token += ":";
            byte[] encoded = Base64.encodeBase64(enketo_api_token.getBytes());

            String urlParameters = "server_url=" + aggregate_server_url + "&form_id=" + form_id;

            URL obj = new URL(enketo_api_url);
            con = (HttpURLConnection) obj.openConnection();

            con.setRequestMethod("POST");
            con.setRequestProperty("Authorization", "Basic " + new String(encoded));
            con.setRequestProperty("User-Agent", USER_AGENT);
            con.setRequestProperty("Accept", "*/*");
            con.setRequestProperty("Accept-Charset", "UTF-8");
            con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");

            // Send post request
            con.setDoOutput(true);
            DataOutputStream wr = new DataOutputStream(con.getOutputStream());
            wr.writeBytes(urlParameters);
            wr.flush();
            wr.close();

            int responseCode = con.getResponseCode();
            logger.info("Enketo API response code : " + responseCode);

            try {
                in = new BufferedReader(new InputStreamReader(con.getInputStream()));
                logger.info("Getting the Enketo URL from InputStream");
            } catch (Exception io) {
                in = new BufferedReader(new InputStreamReader(con.getErrorStream()));
                logger.info("Getting the Error Message from ErrorStream");
            }

            String inputLine = null;
            StringBuffer response = new StringBuffer();

            String responseURL = null;
            logger.info("BufferReader Object : " + in);
            if (in != null) {
                logger.info("BufferReader Object : Not Null ");
                while ((inputLine = in.readLine()) != null) {
                    if (inputLine.contains("message")) {
                        message = inputLine;
                        System.out.println(message);
                    }
                    if (inputLine.contains("https")) {
                        responseURL = inputLine;
                    } else if (inputLine.contains("http")) {
                        logger.error("Enketo api token is compromised! Enketo URL should specify https");
                        responseURL = inputLine;
                    }

                    response.append(inputLine);
                }
                in.close();
            }
            if (message != null) {
                String messageArry[] = message.split("\"");
                if (messageArry.length >= 3)
                    message = messageArry[3];
                resp.setStatus(412);
                resp.setHeader("error", "There was an error obtaining the webform. (message:" + message + ")");
            } else if (responseURL != null) {
                String arryResponseURL[] = responseURL.toString().split(" ");
                for (String token : arryResponseURL) {
                    if (!token.contains("http")) {
                        continue;
                    }
                    token = token.replace("\\", "");
                    token = token.replace("\"", "");
                    token = token.replace(",", "");
                    enketoURL = token;
                }
                resp.setStatus(responseCode);
                resp.setHeader("enketo_url", enketoURL);
                logger.info("Enketo API response URL :" + enketoURL);
            } else {
                resp.setStatus(responseCode);
            }

        } catch (java.net.SocketTimeoutException socketTimeoutException) {
            logger.info("Exception caught while calling enketo api :" + socketTimeoutException.toString());
            resp.setStatus(412);
            resp.setHeader("error", "API at " + enketo_api_url + " is not available");
        } catch (Exception exception) {
            logger.info("Exception caught while calling enketo api :" + exception.toString());
            resp.setStatus(412);
            if (message == null || message.equals("")) {
                message = RESPONSE_ERROR;
            }
            resp.setHeader("error", "There was an error obtaining the webform. (message:" + message + ")");
        } finally {
            if (con != null)
                con.disconnect();
        }

    }

}