index.js

#!/usr/bin/env nodejs

var express = require("express");
var mysql = require("mysql");
var bodyParser = require("body-parser");
var md5 = require('MD5');
var rest = require("./rest.js");
var app = express();



function REST() {
    var self = this;
    self.connectMysql();
};

REST.prototype.connectMysql = function () {
    var self = this;
    var pool = mysql.createPool({
        connectionLimit: 100,
        host: 'localhost',
        user: '*****username******',
        password: '*****password*****',
        database: '****database******',
        debug: false
    });
    pool.getConnection(function (err, connection) {
        if (err) {
            self.stop(err);
            throw err;
        } else {
            self.configureExpress(connection);
        }
    });
}

REST.prototype.configureExpress = function (connection) {
    var self = this;
    app.use(bodyParser.urlencoded({ extended: true }));
    app.use(bodyParser.json());
    var router = express.Router();
    app.use('/', router);
    var rest_router = new rest(router, connection, md5);
    self.startServer();
}

REST.prototype.startServer = function () {
    app.listen(3222, function () {
        console.log("All right ! I am alive at Port 3222.");
    });
}

REST.prototype.stop = function (err) {
    console.log("ISSUE WITH MYSQL n" + err);
    process.exit(1);
}

new REST();

rest.js

#!/usr/bin/env nodejs

var express = require("express");
var mysql = require("mysql");
var md5 = require('MD5');
var bodyParser = require("body-parser");
var async = require("async");

function REST_ROUTER(router, connection, md5) {
    var self = this;
    self.handleRoutes(router, connection, md5);
}

REST_ROUTER.prototype.handleRoutes = function (router, connection, md5) {
    router.get("/", function (req, res) {
        res.json({ "Message": "Hello World !" });
    });

    router.post("/login", function (req, res) {
        var query = "SELECT * FROM ?? WHERE username=?";
        var table = ["user", req.body.username, "pass"];
        query = mysql.format(query, table);
        connection.query(query, function (err, rows) {

            if (err) {
                res.json({ "Error": true, "Message": "Query Issue" });
                return;
            }

            if (rows.length == 0) {
                res.json({ "Error": false, "Message": "User Doesn't Exist" });
                return;
            }

            if (md5(req.body.pass) != rows[0].pass) {
                res.json({ "Error": false, "Message": "Invalid Password" });
                return;
            }

            res.json({ "Error": false, "Message": "Login Successful", "user_id": rows[0].user_id });
            //connection.end();
        });
    });


    router.post("/currentmodel", function (req, res) {
        var query = "SELECT current_model FROM ?? WHERE user_id=?";
        var table = ["model", req.body.user_id,];
        query = mysql.format(query, table);
        connection.query(query, function (err, rows) {
            if (err) {
                res.json({ "Error": true, "Message": "Error Retrieving Current Model" });
                return;
            }
            if (rows[0] == null) {
                res.json({ "Error": true, "Message": "No Model Entries Exist for this User" });
                return;
            }
            res.json({ "Error": false, "Message": "Current Model Retrieved!", "current_model": rows[0] });
            //connection.end();
        });
    });

    router.post("/prevmodel", function (req, res) {
        var query = "SELECT prev_model FROM ?? WHERE user_id=?";
        var table = ["model", req.body.user_id,];
        query = mysql.format(query, table);
        connection.query(query, function (err, rows) {
            if (err) {
                res.json({ "Error": true, "Message": "Error Retrieving Current Model" });
                return;
            }
            if (rows[0] == null) {
                res.json({ "Error": true, "Message": "No Model Entries Exist for this User" });
                return;
            }
            res.json({ "Error": false, "Message": "Prev Model Retrieved!", "prev_model": rows[0] });
            //connection.end();
        });
    });

    router.post("/updatemodel", function (req, res) {
        var updatequery = "UPDATE model SET prev_model=current_model WHERE user_id=?";
        var insert = "UPDATE model SET current_model=? WHERE user_id=?";

        var updatetable = req.body.user_id;
        var inserttable = [req.body.current_model, req.body.user_id];

        async.series({
            one: function (callback) {
                setTimeout(function () {
                    updatequery = mysql.format(updatequery, updatetable);
                    pool.query(updatequery, function (err, rows) {
                        if (err) {
                            res.json({ "Error": true, "Message": "Update Fail: Error Retrieving Update Query" });
                        }
                    });
                    callback(null, 1);
                }, 100);
            },
            two: function (callback) {
                setTimeout(function () {
                    insert = mysql.format(insert, inserttable);
                    pool.query(insert, function (err, rows) {
                        if (err) {
                            res.json({ "Error": true, "Message": "Update Fail: Error Inserting to Table" })
                            
                        }
                    });
                    callback(null, 2);
                }, 200);
            }
        }, function (err, results) {
            // results is now equal to: {one: 1, two: 2}
            res.json({ "Error": false, "Message": "Update Successful" });
            //connection.destroy();
        });
    });
}

module.exports = REST_ROUTER;