Sending emails working locally but not on domain using SendGrid API

Question

I have a React.js webapp with a Node.js server that uses nodemailer-sendgrid-transport to send emails through the SendGrid API, the emails are delivered when I host the site locally on my computer but it does not work hosted on the domain even though I am getting a status: 200 on the request.

Here is my server.js file:

const express = require("express");
const app = express();
require("dotenv").config({path: "../.env"});
const bodyParser = require("body-parser");
const cors = require("cors");
const nodemailer = require("nodemailer");
var sgTransport = require('nodemailer-sendgrid-transport');
const multer = require("multer");

app.use(express.urlencoded({extended: true}));
app.use(express.json());

app.use(cors());

const transport = nodemailer.createTransport(sgTransport({
  auth: {
    api_key: process.env.SG_API_KEY
  }
}));

app.post("/send_schools_form", cors(), async (req, res) => {
  let {
    school,
    address,
    name,
    phone,
    email,
    substitutes
  } = req.body;

  var substitutesList = substitutes.reduce(function(a, b) {
  return a + '</br><ul><li>Startdatum: ' + b.date + '</li><li>Tid: ' + b.time + '</li>    <li>Info: ' + b.info + '</li></ul>';
}, '');

  await transport.sendMail({
    from: process.env.USER_SENDER,
    to: process.env.USER_RECEIVER,
    subject: "Vikarie begäran",
    html: `
    <ul>
      <li>Skola: ${school}</li>
      <li>Adress: ${address}</li>
      <li>Kontaktperson: ${name}</li>
      <li>Telefon: ${phone}</li>
      <li>E-post: ${email}</li>
    </ul>
    <ul>${substitutesList}</ul>
    `
  }, (err) => {
    if (err) {
      console.log(err);
      res.status(400).send('Error');
    } else {
      res.status(200).send('Success');
    }
  })
});

const upload = multer({
  storage: multer.memoryStorage()
});

let middleware = [
  cors(),
  upload.fields([
    {name: "cvFile", maxCount: 1},
    {name: "otherFile", maxCount: 1}
  ])
];

app.post("/send_substitutes_form", middleware, async (req, res) => {
  let {
    firstName,
    lastName,
    email,
    phone,
    address,
    city,
    postalCode,
    availability
  } = req.body;

  await transport.sendMail({
    from: process.env.USER_SENDER,
    to: process.env.USER_RECEIVER,
    subject: "Arbetsansökan",
    html: `
    <ul>
      <li>Namn: ${firstName} ${lastName}</li>
      <li>E-post: ${email}</li>
      <li>Telefon: ${phone}</li>
      <li>Adress: ${address}</li>
      <li>Ort: ${city}, ${postalCode}</li>
      <li>Tillgänglighet: ${availability} dagar per vecka</li>
    </ul>
    `,
    attachments: [{
      filename: req.files["cvFile"][0].originalname,
      content: req.files["cvFile"][0].buffer
    },
    {
      filename: req.files["otherFile"][0].originalname,
      content: req.files["otherFile"][0].buffer
    }]
  }, (err) => {
    if (err) {
      console.log(err);
      res.status(400).send('Error');
    } else {
      res.status(200).send('Success');
    }
  })
});

const PORT = process.env.PORT || 4000;

app.listen(PORT, () => {
  console.log("Server is listening on port " + PORT);
});

Answer 1

The problem seemed to be in the .htaccess file, it was incorrectly redirecting the website request to index.html file instead of the Node Environment, the issue was found and solved by the host provider support.