NJS-500 connection lost

[flash4174]

1. What versions are you using?
   node-oracle V6.6.0
   nodeJS 18
   Oracle instant client 23.5.0.
   Express 4.18.2
   nextJS 14.2.4
   Oracle database: 19c

2. Is it an error or a hang or a crash?

From time to time got njs-500 and I have to restart the Azure webserver to work again

3. What error(s) or behavior you are seeing?
   Website can't connect to the database.
   Njs-500
   Ora-03135

4. Include a runnable Node.js script that shows the problem.
   server.js

const next = require(‘next’)
const express = require(‘express’)
const userRoutes = require(‘/routes/userRoutes’)
const OracleDB = require(‘oracledb’)
const dbConfig = require(‘./config/dbConfig’)

OracleDB.initOracleClient()

const port = 3000
const dev = false
const app = next({dev})

const handle = app.getRequestHandler()

process.env.UV_THREADPOOL_SIZE = 4 + dbConfig.poolMax

app.prepare().then(() => {
     OracleDB.createPool(dbConfig).then(() => {

          const server = express()
          server.use(cookieParser())
          server.use(express.json({limit: “20mb”}))

           server.use(‘/api/user/‘, userRoutes)


          server.all(‘*’, (req, res) => {
              return handle(req,res)
           })

           server.listen(port, (err) => {
               if(err) throw err
               console.log(‘server ready on port 3000’)
           })
    })
})

dbConfig

const dbConfig = {
      user: “username”,
      password: “pass”,
      connectString: “connetction string with enable=broken”,
      poolMax: 30,
      poolMin: 30,
      poolAlias: “mainPool”,
      retryCount: 3,
      expireTime: 3,
      poolPingInterval: 0
}

module.exports = dbConfig

UserRoutes

const express = require(‘express’)
const router = express.Router()

const { getUsers } = require(‘../controllers/userController’)

router.route(‘/‘).get(getUsers)

module.exports = router

UserController

const asyncHandler = require(‘express-async-handler’)
const OracleDB = require(‘oracledb’)

const getUsers = asyncHandler(async(req, res) => {
   let connection = await OracleDB.getConnection(‘mainPool’)
   try {
       const sql = ‘select query’
       const result = await connection.execute(sql)
       If(result){
          res.status(200).json(result)
        }else {
           res.status(401)
        }
    catch(error) {
       console.log(error)
    }
    finally {
        if(connection) {
            try{
                await connection.close()
            } catch {
                console.log(error)
            }
          }
       }
})

module.exports = { getUsers }

[sreguna]

@flash4174 instead of (enable=broken) which uses system defaults can you use (expire_time=n) under the DESCRIPTION section of the connect string. The value(n) is in minutes.

[flash4174]

@flash4174 instead of (enable=broken) which uses system defaults can you use (expire_time=n) under the DESCRIPTION section of the connect string. The value(n) is in minutes.

Thank you for the answer. Now I receive njs-040 time to time.

Do you have any idea?

[sudarshan12s]

@flash4174 instead of (enable=broken) which uses system defaults can you use (expire_time=n) under the DESCRIPTION section of the connect string. The value(n) is in minutes.

Thank you for the answer. Now I receive njs-040 time to time.

Do you have any idea?

@flash4174 ,
If queueTimeout is less, then timeout can happen. Can you adjust it . It normally comes if all connections are busy and poolMax is reached. Hence new connections get timeout error. poolMax can be increased if active/busy connections at any point are large.

some details here