UserConfServlet.java

/*
 * Copyright 2014-2016 CyberVision, Inc.
 *
 * 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.kaaproject.kaa.server.admin.servlet;

import org.codehaus.jackson.map.ObjectMapper;
import org.kaaproject.kaa.common.dto.EndpointUserConfigurationDto;
import org.kaaproject.kaa.server.admin.shared.services.ConfigurationService;
import org.kaaproject.kaa.server.admin.shared.servlet.ServletParams;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.slf4j.helpers.MessageFormatter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.context.support.SpringBeanAutowiringSupport;

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

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


public class UserConfServlet extends HttpServlet implements ServletParams {

  private static final long serialVersionUID = 1584721028432234643L;

  private static final Logger LOG = LoggerFactory.getLogger(UserConfServlet.class);

  private static final int BUFFER = 1024 * 100;

  private static final String JSON = "application/json";

  private static final ObjectMapper FORMATTER = new ObjectMapper();


  private static final String USER_CONFIG_NAME_PATTERN = "UserConfig_{}.v{}.json";

  @Autowired
  private ConfigurationService configurationService;

  @Override
  public void init(ServletConfig config) throws ServletException {
    super.init(config);
    SpringBeanAutowiringSupport
        .processInjectionBasedOnServletContext(this, config.getServletContext());
  }

  @Override
  public void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {

    String externalUId = URLDecoder
        .decode(request.getParameter(USER_EXTERNAL_ID_PARAMETER), "UTF-8");
    String appId = URLDecoder
        .decode(request.getParameter(APPLICATION_ID_PARAMETER), "UTF-8");
    int schemaVersion = Integer
        .parseInt(URLDecoder.decode(request.getParameter(CONFIGURATION_SCHEMA_ID), "UTF-8"));

    try {
      EndpointUserConfigurationDto endpointUserConfigurationDto = configurationService
          .findUserConfigurationByExternalUIdAndAppIdAndSchemaVersion(
              externalUId, appId, schemaVersion);
      String json;
      String fileName = MessageFormatter
          .arrayFormat(USER_CONFIG_NAME_PATTERN, new Object[]{externalUId, appId})
          .getMessage();

      json = endpointUserConfigurationDto.getBody();

      Object jsonObject = FORMATTER.readValue(json, Object.class);
      byte[] body = FORMATTER.writerWithDefaultPrettyPrinter()
          .writeValueAsString(jsonObject)
          .getBytes("UTF-8");
      ServletUtils.prepareDisposition(request, response, fileName);
      response.setContentType(JSON);
      response.setContentLength(body.length);
      response.setBufferSize(BUFFER);
      response.getOutputStream().write(body);
      response.flushBuffer();
    } catch (Exception ex) {
      LOG.error("Unexpected error in ProfileDownloadServlet.doGet: ", ex);
      response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, "Unable to get file: "
          + ex.getMessage());
    }
  }
}