python create persistent connection on a page code example

Example 1: nodejs open default browser on specific web page

$ npm install opn

//////////////////////////////////////////

var opn = require('opn');

// opens the url in the default browser 
opn('http://sindresorhus.com');

// specify the app to open in 
opn('http://sindresorhus.com', {app: 'firefox'});

Example 2: how to manage a db connection in javascript

//put these lines in a seperate file
const mysql = require('mysql2');

const connection = mysql.createPool({
    host: "localhost",
    user: "",
    password: "",
    database: ""
    // here you can set connection limits and so on
});

module.exports = connection;

//put these on destination page
const connection = require('../util/connection');

async function getAll() {
    const sql = "SELECT * FROM tableName";
    const [rows] = await connection.promise().query(sql);
    return rows;
} 
exports.getAll = getAll;