Express Session store.on is not a function

it seems like you have to initialize the KnexSessionStore with the session such as const knexSession = KnexSessionStore(session); and then create the store in base of that const store = new knexSession({...}), something like:

import bodyParser from 'body-parser'
import cors from 'cors'
import dotenv from 'dotenv'
import express from 'express'
import helmet from 'helmet'
import KnexSessionStore from 'connect-session-knex'
import session from 'express-session'

import * as corsOptions from '../config/cors.mjs'

dotenv.config()
const knexSession = KnexSessionStore(session);
const store = new knexSession({
  sidfieldname: 'session-id',
  clearInterval: 60000,
  createtable: true,
  tablename: 'sessions',
})

const app = express()
app.use(bodyParser.json())
app.use(helmet())
app.use(
  session({
    secret: 'secret',
    cookie: {
      maxAge: 1000 * 60 * 60 * 24, // 1 Day
      httpOnly: true,
      secure: false, // Needs to be true
      sameSite: true,
    },
    resave: true,
    saveUninitialized: false,
    store,
  }),
)

You could also try just importing it in the way of const KnexSessionStore = require('connect-session-knex')(session);