database.js

const config = require('./config.js'),
      mysql = require('mysql'),
      mySqlConnection = mysql.createConnection({
        host: '149.4.68.217',
        user: config.DB_READ_USER,
        database: 'bpl_performance_lab',
        password: config.DB_PW
      });

exports.connect = function (callback) {
  mySqlConnection.connect(function (err) {
    if (err) {
      console.error('Error connecting: ' + err.stack);
      return;
    }

    console.log(`Connected as id ${mySqlConnection.threadId}`);
    callback(err, mySqlConnection);
  });
};

server.js

'use strict';
const express = require('express'),
      app = express(),
      database = require('./config/database.js'),
      squel = require('squel'),
      port = process.env.PORT || 8000;

app.use(function (err, req, res, next) {
  res.status(err.status || 500);
  res.json({ error: { message: err.message }});
});

app.get('/api/weather', function (req, res) {
  database.connect(function (err, connection) {
    if (err) throw err;
    let weatherQuery = squel.select({ autoQuoteTableNames: true, autoQuoteFieldNames: true })
        .from('weather').toString();
    connection.query(weatherQuery, function (err, rows) {
      res.send(rows);
    });
  })
});

app.listen(port, function () {
  console.log(`App running on port: ${port}`);
});