text: var MongoClient = require('mongodb').MongoClient,
      test = require('assert');
  // Connection url
  var url = 'mongodb://root:@114.215.138.33/admin';
  // Connect using MongoClient
  module.exports=function(cb){
   MongoClient.connect(url, 
   //{
  //     server: {
  //         poolSize: 20,
  //         socketOpations: { connectTimeoutMS: 500 },
  //         auto_reconnect: true
  //     }
  // }, 
  function (err, db) {
     // console.log(err);
      cb(db);
     // var col = db.collection('createIndexExample1');
  
  });
  }