Extract data from HERA's web site

hera.js

// Extract price and data from your bills from HERA at https://servizionline.gruppohera.it
// Run it in the console on a web page with the list of bills.
// Created: 13/11/2020
// Author: Dmitry Myadzelets
//
(function bollette () {
  const number = /[-]{0,1}[\d]+/g
  const row2object = tr => ({
    euro: Number(tr.querySelector('.importo').querySelector('span').innerText.match(number).join('.')),
    date: tr.querySelector('.emessa').querySelector('span').innerText
  })
  const rows = document.querySelector('.elenco-bollette').querySelectorAll('tr')
  const data = Array.from(rows).map(row2object)
  return data
    // One year 
    //.slice(-12)
    .slice(12)
    // Total
    .reduce((sum, o) => sum += o.euro, 0)
})()