servicio_social_api/server/helper/gmail.js

require('../config/config');           // mantiene tu carga de variables
const nodemailer = require('nodemailer');

const transporter = nodemailer.createTransport({
	host: 'smtp.gmail.com',          // o smtp‑relay.gmail.com (ver punto 2)
	port: 587,
	secure: false,
	requireTLS: true,                  // TLS STARTTLS
	auth: { user: process.env.USER_GMAIL, pass: process.env.PASS_GMAIL },
	pool: true,                      // <‑‑ activa reuse
	maxConnections: 1,               // una sola conexión viva
	maxMessages: 100,                // reabrir después de 100 envíos
	rateDelta: 2000,                 // ventana 1 s
	rateLimit: 1                     // máx. 5 mensajes/seg
});

const gmail = (subject, to, text) =>
  transporter.sendMail({
    from: process.env.USER_GMAIL,
    to,
    subject,
    text,
  });

module.exports = gmail;