Setting up mysql

Author: vibhasfl

index.js

@@ -1,7 +1,20 @@
+import debug from 'debug'
 require('dotenv').load()
+const log = debug('app')
 
-let unusedEnvVars = [ 'MONGO_HOSTNAME', 'MONGO_PORT', 'MONGO_DATABASE' ].filter((i) => !process.env[i])
-if (unusedEnvVars.length) throw new Error('Required ENV variables are not set: [' + unusedEnvVars.join(', ') + ']')
+let applicationEnvVars = [ 'APP_ENVIROMENT', 'PORT', 'USE_MONGODB', 'USE_MYSQL' ]
+let mysqlEnvVars = [ 'MYSQL_HOSTNAME', 'MYSQL_PORT', 'MYSQL_USERNAME', 'MYSQL_DATABASE', 'MYSQL_PASSWORD' ]
+let mongoEnvVars = [ 'MONGO_HOSTNAME', 'MONGO_PORT', 'MONGO_DATABASE' ]
+
+if (process.env.USE_MONGODB) applicationEnvVars = [ ...applicationEnvVars, ...mongoEnvVars ]
+if (process.env.USE_MYSQL) applicationEnvVars = [ ...applicationEnvVars, ...mysqlEnvVars ]
+
+let unusedEnvVars = applicationEnvVars.filter((i) => !process.env[i])
+
+if (unusedEnvVars.length) {
+  log('Required ENV variables are not set: [' + unusedEnvVars.join(', ') + ']')
+  process.exit(1)
+}
 
 const { app } = require('./server/app.js')
 

package.json

@@ -14,7 +14,8 @@
     "helmet": "^3.15.1",
     "joi": "^14.3.1",
     "jsonwebtoken": "^8.4.0",
-    "mongoose": "^5.4.10"
+    "mongoose": "^5.4.10",
+    "mysql": "^2.16.0"
   },
   "devDependencies": {
     "@babel/cli": "^7.2.3",

server/app.js

@@ -8,6 +8,8 @@ import helmet from 'helmet'
 import { httpStatus } from './utils/httpStatus'
 import { AppError } from './utils/appError'
 import { secretCallback } from './utils/secretCallback'
+import { connectMysql } from './config/mysqlconnect'
+
 const app = express()
 
 app.use(bodyParser.json())
@@ -20,7 +22,8 @@ app.use(function (req, res, next) {
   throw new AppError('Resource not found', httpStatus.NOT_FOUND)
 })
 
-connectMongo()
+if (process.env.USE_MONGODB === 'true') connectMongo()
+if (process.env.USE_MYSQL === 'true') connectMysql()
 
 app.use(errorHandler)
 

server/config/errorHandler.js

@@ -8,7 +8,7 @@ const log = debug('app')
 // Note : calling next(err) will call this error handler if no other handler id defined.You can handle custom error over here
 
 const errorHandler = (err, req, res, next) => {
-  log(err)
+  log(err.toString())
 
   if (err instanceof AppError) return res.status(err.status).json({ error: err.message, stack: process.env.APP_ENVIROMENT === 'dev' ? err.stack : undefined })
 

server/config/mongoconnect.js

@@ -6,23 +6,23 @@ const log = debug('app')
 mongoose.Promise = Promise
 
 mongoose.connection.on('connected', () => {
-  log('Connection Established')
+  log('MongoDB Connection Established')
 })
 
 mongoose.connection.on('reconnected', () => {
-  log('Connection Reestablished')
+  log('MongoDB Connection Reestablished')
 })
 
 mongoose.connection.on('disconnected', () => {
-  log('Connection Disconnected')
+  log('MongoDB Connection Disconnected')
 })
 
 mongoose.connection.on('close', () => {
-  log('Connection Closed')
+  log('MongoDB Connection Closed')
 })
 
 mongoose.connection.on('error', (error) => {
-  log('ERROR: ' + error)
+  log('MongoDB ERROR: ' + error)
   process.exit(1)
 })
 

server/config/mysqlconnect.js

@@ -0,0 +1,28 @@
+import mysql from 'mysql'
+import debug from 'debug'
+import util from 'util'
+
+const log = debug('app')
+// Note : You can remove mysqldetaillog and use log instead
+const mysqldetaillog = debug('mysqldetaillog')
+
+const pool = mysql.createPool({ host: process.env.MYSQL_HOSTNAME, user: process.env.MYSQL_USERNAME, password: process.env.MYSQL_PASSWORD, database: process.env.MYSQL_DATABASE })
+
+pool.on('connection', (connection) => mysqldetaillog(`Mysql Connection #${connection.threadId} created`))
+pool.on('acquire', (connection) => mysqldetaillog(`Mysql Connection #${connection.threadId} acquired`))
+pool.on('release', (connection) => mysqldetaillog(`Mysql Connection #${connection.threadId} released`))
+
+pool.query = util.promisify(pool.query)
+
+export const connectMysql = () => {
+  pool.getConnection(function (err, connection) {
+    if (err) {
+      log(`Mysql ${err.toString()}`)
+      process.exit(1)
+    }
+    log(`Mysql connection established`)
+    connection.release()
+  })
+}
+
+export { pool }