org.opentcs.kernel.extensions.servicewebapi.v1.V1RequestHandler Maven / Gradle / Ivy

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/**
 * Copyright (c) The openTCS Authors.
 *
 * This program is free software and subject to the MIT license. (For details,
 * see the licensing information (LICENSE.txt) you should have received with
 * this copy of the software.)
 */
package org.opentcs.kernel.extensions.servicewebapi.v1;

import static java.util.Objects.requireNonNull;

import jakarta.inject.Inject;
import java.util.List;
import java.util.concurrent.ExecutionException;
import org.opentcs.access.KernelRuntimeException;
import org.opentcs.data.ObjectExistsException;
import org.opentcs.data.ObjectUnknownException;
import org.opentcs.kernel.extensions.servicewebapi.HttpConstants;
import org.opentcs.kernel.extensions.servicewebapi.JsonBinder;
import org.opentcs.kernel.extensions.servicewebapi.RequestHandler;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.GetOrderSequenceResponseTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.GetPeripheralAttachmentInfoResponseTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.GetPeripheralJobResponseTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.GetTransportOrderResponseTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.GetVehicleAttachmentInfoResponseTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.PlantModelTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.PostOrderSequenceRequestTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.PostPeripheralJobRequestTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.PostTopologyUpdateRequestTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.PostTransportOrderRequestTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.PostVehicleRoutesRequestTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.PostVehicleRoutesResponseTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.PutVehicleAllowedOrderTypesTO;
import org.opentcs.kernel.extensions.servicewebapi.v1.binding.PutVehicleEnergyLevelThresholdSetTO;
import spark.QueryParamsMap;
import spark.Request;
import spark.Response;
import spark.Service;

/**
 * Handles requests and produces responses for version 1 of the web API.
 */
public class V1RequestHandler
    implements
      RequestHandler {

  private final JsonBinder jsonBinder;
  private final StatusEventDispatcher statusEventDispatcher;
  private final TransportOrderDispatcherHandler orderDispatcherHandler;
  private final TransportOrderHandler transportOrderHandler;
  private final PeripheralJobHandler peripheralJobHandler;
  private final PeripheralJobDispatcherHandler jobDispatcherHandler;
  private final PlantModelHandler plantModelHandler;
  private final VehicleHandler vehicleHandler;
  private final PathHandler pathHandler;
  private final LocationHandler locationHandler;
  private final PeripheralHandler peripheralHandler;

  private boolean initialized;

  @Inject
  public V1RequestHandler(
      JsonBinder jsonBinder,
      StatusEventDispatcher statusEventDispatcher,
      TransportOrderDispatcherHandler orderDispatcherHandler,
      TransportOrderHandler transportOrderHandler,
      PeripheralJobHandler peripheralJobHandler,
      PeripheralJobDispatcherHandler jobDispatcherHandler,
      PlantModelHandler plantModelHandler,
      VehicleHandler vehicleHandler,
      PathHandler pathHandler,
      LocationHandler locationHandler,
      PeripheralHandler peripheralHandler
  ) {
    this.jsonBinder = requireNonNull(jsonBinder, "jsonBinder");
    this.statusEventDispatcher = requireNonNull(statusEventDispatcher, "statusEventDispatcher");
    this.orderDispatcherHandler = requireNonNull(orderDispatcherHandler, "orderDispatcherHandler");
    this.transportOrderHandler = requireNonNull(transportOrderHandler, "transportOrderHandler");
    this.peripheralJobHandler = requireNonNull(peripheralJobHandler, "peripheralJobHandler");
    this.jobDispatcherHandler = requireNonNull(jobDispatcherHandler, "jobDispatcherHandler");
    this.plantModelHandler = requireNonNull(plantModelHandler, "plantModelHandler");
    this.vehicleHandler = requireNonNull(vehicleHandler, "vehicleHandler");
    this.pathHandler = requireNonNull(pathHandler, "pathHandler");
    this.locationHandler = requireNonNull(locationHandler, "locationHandler");
    this.peripheralHandler = requireNonNull(peripheralHandler, "peripheralHandler");
  }

  @Override
  public void initialize() {
    if (isInitialized()) {
      return;
    }

    statusEventDispatcher.initialize();

    initialized = true;
  }

  @Override
  public boolean isInitialized() {
    return initialized;
  }

  @Override
  public void terminate() {
    if (!isInitialized()) {
      return;
    }

    statusEventDispatcher.terminate();

    initialized = false;
  }

  @Override
  public void addRoutes(Service service) {
    requireNonNull(service, "service");

    service.get(
        "/events",
        this::handleGetEvents
    );
    service.post(
        "/vehicles/dispatcher/trigger",
        this::handlePostDispatcherTrigger
    );
    service.post(
        "/vehicles/:NAME/routeComputationQuery",
        this::handleGetVehicleRoutes
    );
    service.put(
        "/vehicles/:NAME/commAdapter/attachment",
        this::handlePutVehicleCommAdapterAttachment
    );
    service.get(
        "/vehicles/:NAME/commAdapter/attachmentInformation",
        this::handleGetVehicleCommAdapterAttachmentInfo
    );
    service.put(
        "/vehicles/:NAME/commAdapter/enabled",
        this::handlePutVehicleCommAdapterEnabled
    );
    service.put(
        "/vehicles/:NAME/paused",
        this::handlePutVehiclePaused
    );
    service.put(
        "/vehicles/:NAME/integrationLevel",
        this::handlePutVehicleIntegrationLevel
    );
    service.post(
        "/vehicles/:NAME/withdrawal",
        this::handlePostWithdrawalByVehicle
    );
    service.post(
        "/vehicles/:NAME/rerouteRequest",
        this::handlePostVehicleRerouteRequest
    );
    service.put(
        "/vehicles/:NAME/allowedOrderTypes",
        this::handlePutVehicleAllowedOrderTypes
    );
    service.put(
        "/vehicles/:NAME/energyLevelThresholdSet",
        this::handlePutVehicleEnergyLevelThresholdSet
    );
    service.put(
        "/vehicles/:NAME/envelopeKey",
        this::handlePutVehicleEnvelopeKey
    );
    service.get(
        "/vehicles/:NAME",
        this::handleGetVehicleByName
    );
    service.get(
        "/vehicles",
        this::handleGetVehicles
    );
    service.post(
        "/transportOrders/dispatcher/trigger",
        this::handlePostDispatcherTrigger
    );
    service.post(
        "/transportOrders/:NAME/immediateAssignment",
        this::handlePostImmediateAssignment
    );
    service.post(
        "/transportOrders/:NAME/withdrawal",
        this::handlePostWithdrawalByOrder
    );
    service.post(
        "/transportOrders/:NAME",
        this::handlePostTransportOrder
    );
    service.put(
        "/transportOrders/:NAME/intendedVehicle",
        this::handlePutTransportOrderIntendedVehicle
    );
    service.get(
        "/transportOrders/:NAME",
        this::handleGetTransportOrderByName
    );
    service.get(
        "/transportOrders",
        this::handleGetTransportOrders
    );
    service.post(
        "/orderSequences/:NAME",
        this::handlePostOrderSequence
    );
    service.get(
        "/orderSequences",
        this::handleGetOrderSequences
    );
    service.get(
        "/orderSequences/:NAME",
        this::handleGetOrderSequenceByName
    );
    service.put(
        "/orderSequences/:NAME/complete",
        this::handlePutOrderSequenceComplete
    );
    service.put(
        "/plantModel",
        this::handlePutPlantModel
    );
    service.get(
        "/plantModel",
        this::handleGetPlantModel
    );
    service.post(
        "/plantModel/topologyUpdateRequest",
        this::handlePostUpdateTopology
    );
    service.put(
        "/paths/:NAME/locked",
        this::handlePutPathLocked
    );
    service.put(
        "/locations/:NAME/locked",
        this::handlePutLocationLocked
    );
    service.post(
        "/dispatcher/trigger",
        this::handlePostDispatcherTrigger
    );
    service.post(
        "/peripherals/dispatcher/trigger",
        this::handlePostPeripheralJobsDispatchTrigger
    );
    service.post(
        "/peripherals/:NAME/withdrawal",
        this::handlePostPeripheralWithdrawal
    );
    service.put(
        "/peripherals/:NAME/commAdapter/enabled",
        this::handlePutPeripheralCommAdapterEnabled
    );
    service.get(
        "/peripherals/:NAME/commAdapter/attachmentInformation",
        this::handleGetPeripheralCommAdapterAttachmentInfo
    );
    service.put(
        "/peripherals/:NAME/commAdapter/attachment",
        this::handlePutPeripheralCommAdapterAttachment
    );
    service.get(
        "/peripheralJobs",
        this::handleGetPeripheralJobs
    );
    service.get(
        "/peripheralJobs/:NAME",
        this::handleGetPeripheralJobsByName
    );
    service.post(
        "/peripheralJobs/:NAME",
        this::handlePostPeripheralJobsByName
    );
    service.post(
        "/peripheralJobs/:NAME/withdrawal",
        this::handlePostPeripheralJobWithdrawal
    );
    service.post(
        "/peripheralJobs/dispatcher/trigger",
        this::handlePostPeripheralJobsDispatchTrigger
    );
  }

  private Object handlePostDispatcherTrigger(Request request, Response response)
      throws KernelRuntimeException {
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    orderDispatcherHandler.triggerDispatcher();
    return "";
  }

  private Object handleGetEvents(Request request, Response response)
      throws IllegalArgumentException,
        IllegalStateException {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        statusEventDispatcher.fetchEvents(
            minSequenceNo(request),
            maxSequenceNo(request),
            timeout(request)
        )
    );
  }

  private Object handlePutVehicleCommAdapterEnabled(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    vehicleHandler.putVehicleCommAdapterEnabled(
        request.params(":NAME"),
        valueIfKeyPresent(request.queryMap(), "newValue")
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handleGetVehicleCommAdapterAttachmentInfo(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        GetVehicleAttachmentInfoResponseTO.fromAttachmentInformation(
            vehicleHandler.getVehicleCommAdapterAttachmentInformation(
                request.params(":NAME")
            )
        )
    );
  }

  private Object handleGetVehicleRoutes(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        PostVehicleRoutesResponseTO.fromMap(
            vehicleHandler.getVehicleRoutes(
                request.params(":NAME"),
                jsonBinder.fromJson(request.body(), PostVehicleRoutesRequestTO.class)
            )
        )
    );
  }

  private Object handlePutVehicleCommAdapterAttachment(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    vehicleHandler.putVehicleCommAdapter(
        request.params(":NAME"),
        valueIfKeyPresent(request.queryMap(), "newValue")
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePostTransportOrder(Request request, Response response)
      throws ObjectUnknownException,
        ObjectExistsException,
        IllegalArgumentException,
        IllegalStateException {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        GetTransportOrderResponseTO.fromTransportOrder(
            transportOrderHandler.createOrder(
                request.params(":NAME"),
                jsonBinder.fromJson(request.body(), PostTransportOrderRequestTO.class)
            )
        )
    );
  }

  private Object handlePutTransportOrderIntendedVehicle(Request request, Response response)
      throws ObjectUnknownException {
    transportOrderHandler.updateTransportOrderIntendedVehicle(
        request.params(":NAME"),
        request.queryParamOrDefault("vehicle", null)
    );
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return "";
  }

  private Object handlePostOrderSequence(Request request, Response response)
      throws ObjectUnknownException,
        ObjectExistsException,
        IllegalArgumentException,
        IllegalStateException {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        GetOrderSequenceResponseTO.fromOrderSequence(
            transportOrderHandler.createOrderSequence(
                request.params(":NAME"),
                jsonBinder.fromJson(request.body(), PostOrderSequenceRequestTO.class)
            )
        )
    );
  }

  private Object handleGetOrderSequences(Request request, Response response) {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        transportOrderHandler.getOrderSequences(
            valueIfKeyPresent(request.queryMap(), "intendedVehicle")
        )
    );
  }

  private Object handleGetOrderSequenceByName(Request request, Response response) {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        transportOrderHandler.getOrderSequenceByName(request.params(":NAME"))
    );
  }

  private Object handlePutOrderSequenceComplete(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException,
        InterruptedException,
        ExecutionException {
    transportOrderHandler.putOrderSequenceComplete(request.params(":NAME"));
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePostImmediateAssignment(Request request, Response response)
      throws ObjectUnknownException {
    orderDispatcherHandler.tryImmediateAssignment(request.params(":NAME"));
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePostWithdrawalByOrder(Request request, Response response)
      throws ObjectUnknownException {
    orderDispatcherHandler.withdrawByTransportOrder(
        request.params(":NAME"),
        immediate(request),
        disableVehicle(request)
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePostWithdrawalByVehicle(Request request, Response response)
      throws ObjectUnknownException {
    orderDispatcherHandler.withdrawByVehicle(
        request.params(":NAME"),
        immediate(request),
        disableVehicle(request)
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePostPeripheralJobWithdrawal(Request request, Response response)
      throws KernelRuntimeException {
    jobDispatcherHandler.withdrawPeripheralJob(request.params(":NAME"));
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePostVehicleRerouteRequest(Request request, Response response)
      throws ObjectUnknownException {
    orderDispatcherHandler.reroute(request.params(":NAME"), forced(request));
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handleGetTransportOrders(Request request, Response response) {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        transportOrderHandler.getTransportOrders(
            valueIfKeyPresent(request.queryMap(), "intendedVehicle")
        )
    );
  }

  private Object handlePutPlantModel(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    plantModelHandler.putPlantModel(jsonBinder.fromJson(request.body(), PlantModelTO.class));
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handleGetPlantModel(Request request, Response response) {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(plantModelHandler.getPlantModel());
  }

  private Object handlePostUpdateTopology(Request request, Response response)
      throws ObjectUnknownException,
        KernelRuntimeException {
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    if (request.body().isBlank()) {
      plantModelHandler.requestTopologyUpdate(new PostTopologyUpdateRequestTO(List.of()));
    }
    else {
      plantModelHandler
          .requestTopologyUpdate(
              jsonBinder.fromJson(request.body(), PostTopologyUpdateRequestTO.class)
          );
    }
    return "";
  }

  private Object handlePutPathLocked(Request request, Response response) {
    pathHandler.updatePathLock(
        request.params(":NAME"),
        valueIfKeyPresent(request.queryMap(), "newValue")
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePutLocationLocked(Request request, Response response) {
    locationHandler.updateLocationLock(
        request.params(":NAME"),
        valueIfKeyPresent(request.queryMap(), "newValue")
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handleGetTransportOrderByName(Request request, Response response) {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        transportOrderHandler.getTransportOrderByName(request.params(":NAME"))
    );
  }

  private Object handleGetVehicles(Request request, Response response)
      throws IllegalArgumentException {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        vehicleHandler.getVehiclesState(
            valueIfKeyPresent(
                request.queryMap(),
                "procState"
            )
        )
    );
  }

  private Object handleGetVehicleByName(Request request, Response response)
      throws ObjectUnknownException {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        vehicleHandler.getVehicleStateByName(request.params(":NAME"))
    );
  }

  private Object handlePutVehicleIntegrationLevel(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    vehicleHandler.putVehicleIntegrationLevel(
        request.params(":NAME"),
        valueIfKeyPresent(request.queryMap(), "newValue")
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePutVehiclePaused(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    vehicleHandler.putVehiclePaused(
        request.params(":NAME"),
        valueIfKeyPresent(request.queryMap(), "newValue")
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePutVehicleAllowedOrderTypes(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    vehicleHandler.putVehicleAllowedOrderTypes(
        request.params(":NAME"),
        jsonBinder.fromJson(request.body(), PutVehicleAllowedOrderTypesTO.class)
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePutVehicleEnergyLevelThresholdSet(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    vehicleHandler.putVehicleEnergyLevelThresholdSet(
        request.params(":NAME"),
        jsonBinder.fromJson(request.body(), PutVehicleEnergyLevelThresholdSetTO.class)
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePutVehicleEnvelopeKey(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    vehicleHandler.putVehicleEnvelopeKey(
        request.params(":NAME"),
        valueIfKeyPresent(request.queryMap(), "newValue")
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePostPeripheralWithdrawal(Request request, Response response)
      throws KernelRuntimeException {
    jobDispatcherHandler.withdrawPeripheralJobByLocation(request.params(":NAME"));
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handlePutPeripheralCommAdapterEnabled(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    peripheralHandler.putPeripheralCommAdapterEnabled(
        request.params(":NAME"),
        valueIfKeyPresent(request.queryMap(), "newValue")
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handleGetPeripheralCommAdapterAttachmentInfo(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        GetPeripheralAttachmentInfoResponseTO.fromAttachmentInformation(
            peripheralHandler.getPeripheralCommAdapterAttachmentInformation(
                request.params(":NAME")
            )
        )
    );
  }

  private Object handleGetPeripheralJobs(Request request, Response response) {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        peripheralJobHandler.getPeripheralJobs(
            valueIfKeyPresent(request.queryMap(), "relatedVehicle"),
            valueIfKeyPresent(request.queryMap(), "relatedTransportOrder")
        )
    );
  }

  private Object handlePutPeripheralCommAdapterAttachment(Request request, Response response)
      throws ObjectUnknownException,
        IllegalArgumentException {
    peripheralHandler.putPeripheralCommAdapter(
        request.params(":NAME"),
        valueIfKeyPresent(request.queryMap(), "newValue")
    );
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    return "";
  }

  private Object handleGetPeripheralJobsByName(Request request, Response response) {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        peripheralJobHandler.getPeripheralJobByName(request.params(":NAME"))
    );
  }

  private Object handlePostPeripheralJobsByName(Request request, Response response) {
    response.type(HttpConstants.CONTENT_TYPE_APPLICATION_JSON_UTF8);
    return jsonBinder.toJson(
        GetPeripheralJobResponseTO.fromPeripheralJob(
            peripheralJobHandler.createPeripheralJob(
                request.params(":NAME"),
                jsonBinder.fromJson(request.body(), PostPeripheralJobRequestTO.class)
            )
        )
    );
  }

  private Object handlePostPeripheralJobsDispatchTrigger(Request request, Response response) {
    response.type(HttpConstants.CONTENT_TYPE_TEXT_PLAIN_UTF8);
    jobDispatcherHandler.triggerJobDispatcher();
    return "";
  }

  private String valueIfKeyPresent(QueryParamsMap queryParams, String key) {
    if (queryParams.hasKey(key)) {
      return queryParams.value(key);
    }
    else {
      return null;
    }
  }

  private long minSequenceNo(Request request)
      throws IllegalArgumentException {
    String param = request.queryParamOrDefault("minSequenceNo", "0");
    try {
      return Long.parseLong(param);
    }
    catch (NumberFormatException exc) {
      throw new IllegalArgumentException("Malformed minSequenceNo: " + param);
    }
  }

  private long maxSequenceNo(Request request)
      throws IllegalArgumentException {
    String param = request.queryParamOrDefault("maxSequenceNo", String.valueOf(Long.MAX_VALUE));
    try {
      return Long.parseLong(param);
    }
    catch (NumberFormatException exc) {
      throw new IllegalArgumentException("Malformed minSequenceNo: " + param);
    }
  }

  private long timeout(Request request)
      throws IllegalArgumentException {
    String param = request.queryParamOrDefault("timeout", "1000");
    try {
      // Allow a maximum timeout of 10 seconds so server threads are only bound for a limited time.
      return Math.min(10000, Long.parseLong(param));
    }
    catch (NumberFormatException exc) {
      throw new IllegalArgumentException("Malformed timeout: " + param);
    }
  }

  private boolean immediate(Request request) {
    return Boolean.parseBoolean(request.queryParamOrDefault("immediate", "false"));
  }

  private boolean disableVehicle(Request request) {
    return Boolean.parseBoolean(request.queryParamOrDefault("disableVehicle", "false"));
  }

  private boolean forced(Request request) {
    return Boolean.parseBoolean(request.queryParamOrDefault("forced", "false"));
  }

}