Simple API for fetching keywords in database with express and mongodb

app.js

var util = require('util');
var mongoose = require('mongoose');
    mongoose.connect('mongodb://localhost/dexter', { useMongoClient: true });
    mongoose.Promise = global.Promise;

var database = require('./models/database.js');

var express = require('express');
var app = express();


var connection = mongoose.connection;
    connection.on('connected', function(stats, err){
        console.log("Connected to mongodb server on port 27017");
    });
    connection.on('error', function(err){
        console.log("Error to connected to mongodb server on port 27017");
    });

var Cert = mongoose.model("certs", database);

app.get('/search/', function(req, res){

	var query = req.query.q;

	Cert.find({keywords: query}, function(err, certs) {
		if (err) {
      		throw err;
    	}
    	if (req.query.q && certs.length >= 1) {
              
             var keyswords = JSON.parse(JSON.stringify(certs));

             var total = [];

             for (var i = 0; i < keyswords.length; i++) {
                 var certskeywords = keyswords[i];
                 if (certskeywords.keywords.length >= 2) {
                    total.push(certskeywords);
                 }
             }

             res.send(util.format('%s total %d  of %d', JSON.stringify(total), total.length, certs.length));

    	} else if (certs.length <= 0) {
        res.send("0 Results Found");
      }
      else {
    		res.send("sorry we did not recognize this request!");
    	}
	});
});



app.listen(31337, function() {
	console.log('Listenning on port 31337');
});