.js

var Promise = require('bluebird');

var mysql = require('mysql');
var fs    = require('fs');
var args  = process.argv;
 
// Configure MySql connection
var con = Promise.promisifyAll(mysql.createConnection({
  host: 'localhost',
  user: 'friroot',
  password: 'friserver2015',
  database: 'naviserver'
}));


// Attempt to establish MySql connection
con.connectAsync()
.then(function () {
    console.log('Connection to mysql database established.');
    return import_locations();
})
.catch(function (err) {
    console.log('Could not connect to mysql database: ' + error.message);
})
.finally(function () {
    con.destroy();
});    

function import_locations() {
  // Check if user has provided name of the json locations file
  if(args.length < 3) {
    console.log('Missing locations import file.');
    return;
  }
  
  console.log('Importing file: ' + args[2]);
 
  // Attempt to parse locations import file
  var json = JSON.parse(fs.readFileSync('./' + args[2], 'utf8'));
  console.log('Successfully parsed ' + args[2] + '.');

  var name  = json.name;                // Map name
  var floor = json.floor;               // Name of the floor
  var locations = json.locations;       // Reference points

  console.log('Inserting ' + locations.length + ' rows.');

  // using reduce here for the side effect of running in sequence
  return Promise.reduce(locations, function (location) {
    params = {
      x: location.x,
      y: location.y,
      name: name,
      floor: floor,
      mag_strength: location.magnetic
    };
    signals = location.signals;

    // Insert location if successful id is returned to be able to insert
    // signals associated with location in bulk.
    return con.queryAsync('INSERT INTO locations SET ?', params)
    .then(function (result) {
      // Access point to which signal results belong to
      var id = result.insertId;
      
      // Access point list associated with location
      var access_points = [];

      for(var j = 0; j < signals.length; j++) {
        signal = signals[j];
        access_points.push([id, signal.bssid, signal.level]);
      }

      // Bulk insert all signals for this location
      return con.queryAsync('INSERT INTO signals (location_id, bssid, level) VALUES ?', [access_points]);
    });
  }).tap(function () {
    console.log('Map and location data imported.');
  });
}