how to use multiple RPC endpoints with ethers to reconnect on error

ethers-provider-fallback.js

const { ethers } = require('ethers')

const endpoints = [
  // main rpc endpoint
  'http://localhost:8545',
  // fallback one
  'https://fallback-rpc-endpoint/12345',
  // fallback two
  'https://another-fallback-rpc-endpoint/12345',
]

let ethersProvider
let retries = 0
let isAlive = false

const initProvider = async () => {
  // reset
  isAlive = false
  retries = 0

  console.log('Initialising Ethers provider', retries)

  while (!isAlive) {
    if (retries > endpoints.length) {
      console.log('All nodes are down!')
      break
    }
    try {
      console.log(`${retries} try, now with enpoint ${endpoints[retries]}`)
      // for WSS
      // ethersProvider = new ethers.providers.WebSocketProvider(endpoints[retries])

      // For HTTP providers
      ethersProvider = new ethers.providers.JsonRpcProvider(endpoints[retries])

      // ethersProvider.ready() does not work 😕
      isAlive = await ethersProvider.getNetwork()
      console.log('isAlive :>> ', isAlive)

      // For WSS providers
      // ethersProvider.on('error', async () => {
      //    console.log('Error captured >>>>>>>>', error)
      //    isAlive = false
      //    await initProvider()
      // })
    } catch (error) {
      console.error('Error initialising provider')
      retries++
    }
  }
}

// blockchain example method
const checkBlock = async () => {
  try {
    return await ethersProvider.getBlockNumber()
  } catch (error) {
    console.error(error)
    throw error
  }
}

const main = async () => {
  await initProvider()

  //
  try {
    let blockN = await checkBlock()
    console.log('block number is :>> ', blockN)
  } catch (error) {
    initProvider()
  }

  // forces error
  ethersProvider = null

  try {
    blockN = await checkBlock()
    console.log('block number is :>> ', blockN)
  } catch (error) {
    initProvider()
  }
  try {
    blockN = await checkBlock()
    console.log('block number is :>> ', blockN)
  } catch (error) {
    initProvider()
  }

  try {
    blockN = await checkBlock()
    console.log('block number is :>> ', blockN)
  } catch (error) {
    initProvider()
  }
  try {
    blockN = await checkBlock()
    console.log('block number is :>> ', blockN)
  } catch (error) {
    initProvider()
  }
}

main()