code: /*******************************************************************************
   * Copyright 2018 572682
   * 
   * 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 us.dot.its.jpo.ode.pdm;
  
  import java.io.IOException;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.snmp4j.ScopedPDU;
  import org.snmp4j.event.ResponseEvent;
  import org.springframework.http.HttpStatus;
  import org.springframework.http.ResponseEntity;
  import org.springframework.web.bind.annotation.PostMapping;
  import org.springframework.web.bind.annotation.RequestBody;
  import org.springframework.web.bind.annotation.RestController;
  
  import us.dot.its.jpo.ode.plugin.RoadSideUnit.RSU;
  import us.dot.its.jpo.ode.snmp.SnmpSession;
  import us.dot.its.jpo.ode.util.JsonUtils;
  
  @RestController
  public class PdmController {
  
     private static Logger logger = LoggerFactory.getLogger(PdmController.class);
  
     @PostMapping(value = "/pdm", produces = "application/json")
     public ResponseEntity<String> pdmMessage(@RequestBody String jsonString) {
        if (null == jsonString) {
           logger.error("PDM controller received empty request");
           return ResponseEntity.status(HttpStatus.BAD_REQUEST).body("Empty request");
        }
  
        J2735PdmRequest pdmRequest = (J2735PdmRequest) JsonUtils.fromJson(jsonString, J2735PdmRequest.class);
  
        String jsonPdmRequest = pdmRequest.toJson(true);
        logger.debug("J2735PdmRequest: {}", jsonPdmRequest);
  
        String aggregateBodyMessage = "[";
        ScopedPDU pdu = PdmUtil.createPDU(pdmRequest.getPdm());
        for (RSU curRsu : pdmRequest.getRsuList()) {
  
           String curRsuMessage = "Error";
  
           ResponseEvent response = null;
           try {
              response = createAndSend(pdu, curRsu);
              if (null == response || null == response.getResponse()) {
                 curRsuMessage = "Timeout";
              } else if (0 == response.getResponse().getErrorStatus()) {
                 curRsuMessage = "Deposit successful";
              } else {
                 curRsuMessage = "Deposit failed: " + response.getResponse().getErrorStatusText();
              }
           } catch (IOException e) {
              logger.error("Exception sending PDM: ", e);
              curRsuMessage = "Exception occurred";
           }
  
           if (!("[".equals(aggregateBodyMessage))) {
              // Add a comma after the first message
              aggregateBodyMessage = aggregateBodyMessage.concat(",");
           }
  
           aggregateBodyMessage = aggregateBodyMessage.concat("{\"" + curRsu.getRsuTarget() + "\":\"" + curRsuMessage + "\"}");
        }
  
        aggregateBodyMessage = aggregateBodyMessage.concat("]");
        aggregateBodyMessage = "{\"rsu_responses\":".concat(aggregateBodyMessage).concat("}");
  
        return ResponseEntity.status(HttpStatus.OK).body(aggregateBodyMessage);
     }
  
     public static ResponseEvent createAndSend(ScopedPDU pdu, RSU rsu) throws IOException {
        SnmpSession session = new SnmpSession(rsu);
  
        return session.set(pdu, session.getSnmp(), session.getTarget(), false);
     }
  
  }
  