index.js

const path = require('path')
require('dotenv').config({
    path: path.resolve(__dirname, './.env')
})
const net = require('net')
const Web3 = require("web3")
const noti_bot = require('noti_bot')
const notifyTelegram = noti_bot.telegram
const notifySlack = noti_bot.slack
const THRESHOLD = parseFloat(process.env.DELAY_THRESHOLD)

const main = async () => {
    let web3, localWeb3, latestBlockNumber, localLatestBlockNumber
    try {
        web3 = new Web3(new Web3.providers.HttpProvider(process.env.RPC_ENDPOINT))
        latestBlockNumber = await web3.eth.getBlockNumber()
    } catch (err) {
        console.log("Unable to connect public rpc at ", process.env.RPC_ENDPOINT)
        console.log(err)
        let msg = "Cannot connect public rpc " + process.env.RPC_ENDPOINT
        notifyTelegram(msg, process.env.TELEGRAM_TOKEN, process.env.TELEGRAM_CHAT)
        notifySlack(msg, process.env.SLACK_HOOK_KEY, process.env.SLACK_CHANNEL, process.env.SLACK_BOTNAME, process.env.SLACK_ICON)
        process.exit(1)
    }
    try {
        localWeb3 = new Web3(new Web3.providers.IpcProvider(process.env.LOCAL_IPC_PATH, net))
        localLatestBlockNumber = await localWeb3.eth.getBlockNumber()
    } catch (err) {
        let msg = "Your node seems to be down. Your ipcPath: " + process.env.LOCAL_IPC_PATH
        console.log(msg)
        console.log(err)
        notifyTelegram(msg, process.env.TELEGRAM_TOKEN, process.env.TELEGRAM_CHAT)
        notifySlack(msg, process.env.SLACK_HOOK_KEY, process.env.SLACK_CHANNEL, process.env.SLACK_BOTNAME, process.env.SLACK_ICON)
        process.exit(1)
    }
    if (localLatestBlockNumber < latestBlockNumber - THRESHOLD) {
        let coinbase = await localWeb3.eth.getCoinbase()
        let msg = "This node coinbase: " + coinbase + " is slow. RPCCurrentBlock=" + latestBlockNumber + " YourCurrentBlock=" + localLatestBlockNumber
        notifyTelegram(msg, process.env.TELEGRAM_TOKEN, process.env.TELEGRAM_CHAT)
        notifySlack(msg, process.env.SLACK_HOOK_KEY, process.env.SLACK_CHANNEL, process.env.SLACK_BOTNAME, process.env.SLACK_ICON)
        console.log(msg)
    } else {
        console.log("Your node is up to date at block " + localLatestBlockNumber)
    }
    process.exit(0)
}
main()