Whenever querying data from MySQL database it gives an error aws lambda function timed out

Question

In my node.js file the code is as follows:

const dbConfig = require('./config/dbConfig')
const mysql = require('mysql')

var con = mysql.createConnection({
  host: dbConfig.host,
  user: dbConfig.username,
  password: dbConfig.password,
  database: dbConfig.database
})

function readMessages (event, context, callback) {
  console.log('function triggered')
  con.connect((err) => {
    if (err) {
      console.error(err)
      callback(err)
    } else {
      console.log('Connected!')
      con.query('SELECT * FROM Messages WHERE isDeleted = 0;', (err, result, fields) => {
        if (err) {
          console.error(err)
          callback(err)
        } else {
          console.log(result)
          con.end()
          callback(null, result)
        }
      })
    }
  })
}

exports.handler = readMessages

This code positively retrieves data from the MySQL database and displays it on the screen whenever I am running it on my local machine.

However, I got Task timed out after 7.01 seconds error when it is run on aws-lambda.
But, whenever I try to run it on AWS-Lambda, it states an error that the Task got timed out after 7.01

The code and its dependencies are packaged in a file named app.zip, then were uploaded into aws-lambda.

app.zip
├── config
│   └── dbConfig.js
├── index.js
└── node_modules

The only log message printed by the function I have created is function triggered, I cant really find other log messages being generated by my function in the cloud watch log.

Why does the function timed out on aws-lambda?

Answer 1

I am damn sure that it is a permissions issue, whenever you run it on local it is of course going to grab credentials from your local machine/environment & whenever you run this in lambda, you need to assign a role to the lambda that has the permissions it needs to access the mysql database.

Also, don't forget to make MySQL Database accessible to Lambda which you're not trying to access a mysql database that is local to your machine from the lambda function.