periodically check if doto blog has got updated

wait-for-patch.js

const http = require('http')
const interval = 3000

console.log('ctrl+c to stop')
checkUpdate()

let dotohtml = null
async function checkUpdate () {
    try {
        const newhtml = await getPage('http://blog.dota2.com/')
        if (dotohtml !== null) {
            if (dotohtml === newhtml) {
                console.log('no change')
            } else {
                console.log('doto page updated!!!\u0007')
            }
        } else {
            console.log('first fetching')
            dotohtml = newhtml
        }
    } catch (error) {
        console.error('failed to get the page')
    }
    setTimeout(checkUpdate, interval)
}

function getPage(url) {
  return new Promise((resolve, reject) => {
    http.get(url, (res) => {
        let data = ''
        
         res.on('data', (chunk) => {
            data += chunk
         })
        
         res.on('end', () => {
            resolve(data)
         })
    }).on('error', (err) => {
        reject(err)
    })
  })
}