gmail_attachment_checker.js

// ==UserScript==
// @name         GMail Attachments Check
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  Alert when unwanted senders or attachments are added to the mail.
// @author       rcbadiale
// @match        *://mail.google.com/mail/*
// @grant        none
// ==/UserScript==


// *********************************************************
// List of names / emails allowed to be used
// Subject pattern: <TEXT> - <COMPANY>
var allowlist = {
  // 'COMPANY': ['EMAIL1@EMAIL.com, 'EMAIL2@EMAIL.com']
  'ABC': ['test@abc.com',],
  'DEF': ['test@def.com',],
}
// *********************************************************


class Email {
  constructor(emails, subject, attachments) {
    this.emails = emails;
    this.subject = subject;
    this.attachments = attachments;
  }
}

(function() {
  var flag = false;
  var observer = new MutationObserver(function() {
    // var mail_window = document.getElementsByClassName('AD');
    var attachments = document.getElementsByClassName('dL');
    if (attachments.length > 0 & flag === false) {
      console.log('New attachment! :)');
      createCheckButton();
      document.getElementsByClassName('dC')[0].style.display = 'none';
      flag = true;
    }
    else if (attachments.length === 0 & flag === true) {
      console.log('No more attachments! :(');
      deleteCheckButton();
      document.getElementsByClassName('dC')[0].style.display = '';
      flag = false;
    }
  })
  observer.observe(document, {'childList': true, 'subtree': true});
})();

function createCheckButton() {
  var bar = document.getElementsByClassName('btC')[0];
  var cell = document.createElement('td');
  cell.setAttribute('class', 'gU Up');
  cell.id = 'user-check-button';
  cell.style.paddingRight = '5px';
  var check_button = document.createElement('button');
  check_button.innerText = 'Check!';
  check_button.setAttribute('class', 'T-I-atl');
  check_button.style.backgroundColor = '#FBBC04';
  check_button.style.color = 'black';
  check_button.addEventListener('click', checkData);
  check_button.addEventListener('mouseover', function() {
    check_button.style.filter = 'contrast(120%)';
  });
  check_button.addEventListener('mouseout', function() {
    check_button.style.filter = '';
  });
  cell.append(check_button);
  bar.prepend(cell);
}

function deleteCheckButton() {
  var cell = document.getElementById('user-check-button');
  cell.remove();
}

function checkData() {
  // Show send button
  document.getElementsByClassName('dC')[0].style.display = '';
  
  // Read data
  var email = new Email(getEmails(), getSubject(), getAttachments());
  console.log(email);
  
  // Get status
  let allow = true;
  let allowed = '';
  let keys = Object.keys(allowlist);
  let text = 'Algo errado não está certo! :(\n'
  // Define which allowlist to use
  keys.forEach(function(key) {
    if (email.subject.includes(' - ' + key)) allowed = key;
  });
  // Check attachments for unwanted names
  email.attachments.forEach(function(el) {
    if (!el.includes(allowed)) {
      allow = false;
      text += 'Anexo: ' + el + '\n'
    }
    console.log(el, allow)
  });
  // Check if emails are not on the allowlist
  email.emails.forEach(function(el) {
    if (!allowlist[allowed].includes(el)) {
      allow = false;
      text += 'Email: ' + el + '\n'
    }
    console.log(el, allow)
  });
  
  // Treatment
  let cell = document.getElementById('user-check-button')
  let button = cell.getElementsByTagName('button')[0];
  if (allow) button.style.backgroundColor = '#34A853';
  else {
    button.style.backgroundColor = '#EA4335';
    alert(text);
  }
}

function getEmails() {
  var emails = Array();
  var el_emails = Array.from(document.getElementsByClassName('vR'));
  el_emails.forEach(function(el){
    emails.push(el.children[0].attributes.email.value);
  });
  return emails;
}

function getSubject() {
  return document.getElementsByClassName('aoT')[0].value
}

function getAttachments() {
  var attachments = Array();
  let attachments_bar = Array.from(document.getElementsByClassName('dL'));
  attachments_bar.forEach(function(element){
    if (!attachments.includes(element.textContent)) {
      attachments.push(element.textContent);
    }
  });
  return attachments;
}