Notes Sync with MYSQL

var mysql      = require('mysql');
var mysqlParams = {
  host     : 'localhost',
  user     : 'pk_central',
  password : 'xyz786',
  database : 'pk_central'
};

var _ = require("lodash");
var Firebird = require('node-firebird');
var options = {};

options.host = '192.168.10.100';
options.port = 3050;
options.database = 'C:\\PKS4\\Data\\cmpdwin.pkf';
options.user = 'READONLYUSER';
options.password = 'ReadOnly1234$';
options.role = null;            // default
options.pageSize = 4096;        // default when creating database

var cleanupObj = (obj) => {
  _.each(obj, (v, k) => {
    if(_.isNull(v) || _.isUndefined(v)) {
      obj[k] = null;
    } else if(_.isDate(v)) {
      obj[k] = v.getTime();
    } else if(_.isBuffer(v)) {
      obj[k] = v.toString('utf8');
    }
  });
};

var busy;
var perpage = 50;
var semaphore = 0;
Firebird.attach(options, function(err, db) {
     if (err)
         throw err;
     var count_query = 'SELECT COUNT(*) FROM DOCTOR';
     db.query(count_query, function(err, result) {
       if (err)
              throw err;
        var total = result[0].COUNT;
        var pages = _.range(Math.ceil(total/perpage));
        _.each(pages, (p) => {
          busy = true;
          var data_query = 'SELECT FIRST '+perpage+' SKIP '+p*perpage+' DOCTOR_ID, MEMO FROM DOCTOR';
          console.log('COUNT QUERY: '+count_query);
          console.log('FETCH QUERY: '+data_query);
          db.query(data_query, function(err, result) {
            semaphore = 0;
            _.each(result, (tablerow) => {
              if(_.isFunction(tablerow.MEMO)) {
                semaphore++;
                tablerow.memo_string = '';
                tablerow.MEMO(function(err, name, e) {
                  if (err)
                  throw err;
                  e.on('data', function(chunk) {
                    tablerow.memo_string += chunk.toString("utf8").replace(/\\u([0-9]|[a-fA-F])([0-9]|[a-fA-F])([0-9]|[a-fA-F])([0-9]|[a-fA-F])/, '').replace(/\0[\s\S]*$/g,'');
                  });

                  e.on('end', function() {
                    semaphore--;
                    semaphore++;
                    var connection = mysql.createConnection(mysqlParams);
                    connection.connect();
                    connection.query('REPLACE INTO DOCTOR_NOTES SET DOCTOR_ID = ?, NOTES = ?', [tablerow.DOCTOR_ID, tablerow.memo_string], function(err, result) {
                      semaphore--;
                      if(err) throw err;
                    });
                    connection.end();
                  });
                });
              }
              require('deasync').loopWhile(() => { return semaphore>0 });
            });
            busy = false;
          });
          require('deasync').loopWhile(() => { return busy });
        });
        db.detach();
     });
});