database.js

const util = require('util')
const mysql = require('mysql')
const config=require("./config.json");

const pool = mysql.createPool
({
  connectionLimit: 10,
  host: "localhost",
  user: config.sqluser,
  password: config.sqlpass,
  database: config.sqldatabase
})

// Ping database to check for common exception errors.
pool.getConnection((err, connection) =>
{
  if(err)
  {
    if (err.code === 'PROTOCOL_CONNECTION_LOST')
      console.error('Database connection was closed.')
    if (err.code === 'ER_CON_COUNT_ERROR')
      console.error('Database has too many connections.')
    if (err.code === 'ECONNREFUSED')
      console.error('Database connection was refused.')
  }

  if (connection) connection.release()

  return
})

// Promisify for Node.js async/await.
pool.query = util.promisify(pool.query)

module.exports = pool