Source: weather_report_forecast/svc.js

/***
 * Copyright 2015 RAPP
 *
 * 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.
 *
 * Authors: Konstantinos Panayiotou
 * Contact: klpanagi@gmail.com
 *
 */


/**
 * @fileOverview
 *
 * [Weather-Report-Forecast] RAPP Platform front-end web service.
 *
 *  @author Konstantinos Panayiotou
 *  @copyright Rapp Project EU 2015
 */


var path = require('path');

var interfaces = require(path.join(__dirname, 'iface_obj.js'));

const rosSrvName = "/rapp/rapp_weather_reporter/weather_forecast";



/**
 *  [Weather-Report-Forecast]
 *  Handles requests to weather_report_forecast RAPP Platform Service
 *
 *  Service Implementation.
 *
 */
function svcImpl(req, resp, ros) {
  var rosMsg = new interfaces.ros_req();
  rosMsg.city = req.body.city;
  rosMsg.weather_reporter = req.body.weather_reporter;
  rosMsg.metric = req.body.metric;

  // ROS-Service response callback.
  function callback(data) {
    // Parse rosbridge message and craft client response
    var response = parseRosbridgeMsg( data );
    resp.sendJson(response);
  }

  // ROS-Service onerror callback.
  function onerror(e) {
    var response = new interfaces.client_res();
    response.error = e;
    resp.sendJson(response);
  }

  // Call ROS-Service.
  ros.callService(rosSrvName, rosMsg, {success: callback, fail: onerror});
}


/***
 * Craft response object.
 *
 *  @param {Object} rosbridge_msg - Return message from rosbridge
 *
 *  @returns {Object} response - Response Object.
 *  @returns {Array} response.forecast - Weather forecast entries
 *  @returns {String} response.error - Error message
 *
 */
function parseRosbridgeMsg(rosbridge_msg)
{
  var response = new interfaces.client_res();
  const forecast = rosbridge_msg.forecast;

  const error = rosbridge_msg.error;

  if (error) {
    response.error = error;
    return response;
  }

  for (let i in forecast){
    let forecastEntry = new interfaces.forecast_entry();
    forecastEntry.high_temp = forecast[i].high_temperature;
    forecastEntry.low_temp = forecast[i].low_temperature;
    forecastEntry.description = forecast[i].description;
    forecastEntry.date = forecast[i].date;
    response.forecast.push(forecastEntry);
  }

  return response;
}


module.exports = svcImpl;