population.js

var Promise = require('bluebird');
var request = require('request');
/**
 * Find the temperature at a location
 * @param {String} zipcode
 * @param {function} callBack
 * @return {Promise}
 */
var findPopulationByZipCode = function(zipcode, callBack){
  var temp;
  var def = Promise.defer();
  var url = 'http://www.mocky.io/v2/546645359040dd0a01196e83'
  var options = {
    url: url,
    json: true
  };
  request(options, function(err, response, body){
    if(err){
      if(callBack){
        callBack(err);
      }
      def.reject(err);
    }
    else{
      if(body && body.population){
        temp = body.population;
      }
      if(callBack){
        callBack(null, temp);
      }
      def.resolve(temp);
    }
  });

  return def.promise;
}

module.exports = {
  findPopulationByZipCode: findPopulationByZipCode
}