<pre>
var express = require('express');
    var socket = require('socket.io');
    var mysql = require('mysql');
    var http = require("http");
    var app = express();
    var server = app.listen(4000,function(){
        console.log('Listening 4000');
    });
    var io = socket(server);
    app.use(express.static('public'));

    var connectSql = mysql.createConnection({
        host: "localhost",
        user: "root",
        password: "root",
        database: "grid_component",
        socketPath: '/Applications/MAMP/tmp/mysql/mysql.sock'
    });
    connectSql.connect();
    app.get('/api/motor_details', function(req, res) {
        var device_id = req.param('deviceId');
        var a = req.param('a');
        var b = req.param('b');
        var c = req.param('c');
        var entries = {
            device_id: device_id,
            a: a,
            b: b,
            c: c,
            date: '2018-06-27'
        }
        var query = connectSql.query('insert into entries set ?', entries,function (err, result) {
            if(err){
                console.error(err);
                return;
            }
        })
    });
    io.on('connection',function(socket){
        connectSql.query('SELECT * FROM entries',function(err,rows){
            if(err) throw err;
            socket.emit('showrows', rows);
        });
    });
</pre>

<pre>
var socket = io.connect('http://localhost:4000');
 socket.emit('showrows');
 socket.on('showrows', function(rows) {
     var html='';
     for(var i=0; i<rows.length; i++){
         html += rows[i].device_id + ' ' + rows[i].a + '<br>';
     }
     document.getElementById("display").innerHTML = html;
 });
</pre>

[![Error Screenshot][1]][1]