Why are environment variables undefined?

Question

Node.js

There is an .env file containing variables like this: REACT_APP_EMAIL = email REACT_APP_PASS = password
When these variables are called, they are undefined.
Project structure:

Calling variables in server.js (using dotenv)

const dotenv = require('dotenv');
dotenv.config();

const express = require('express');
const bodyParser = require('body-parser');
const nodemailer = require('nodemailer');

const app = express();


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

app.post('/contacts', (req, res) => {
  console.log(req.body);
  console.log(process.env)
    nodemailer.createTestAccount((err, account) => {
        const htmlEmail = `
        <h3>Contact details</h3>
        <ul>
        <li>Name: ${req.body.name}</li>
        <li>Email: ${req.body.email}</li>
        </ul>
        <h3>Message</h3>
        <p>${req.body.message}</p>
        `;
        let transporter = nodemailer.createTransport({
            service: 'gmail',
            host: 'smtp.gmail.com',
            port: 587,
            secure: true,
            requireTLS: true,
            auth: {
                user: process.env.REACT_APP_EMAIL,
                pass: process.env.REACT_APP_PASS
            }
        })



        transporter.verify(function(error, success) {
            if (error) {
              console.log(error);
            } else {
              console.log("Server is ready to take our messages");
            }
          });
        let mailOptions = {
            from: '',
            to: '[email protected]',
            subject: 'New message',
            text: req.body.message,
            html: htmlEmail
        }
        transporter.sendMail(mailOptions, (err, info) => {
            if(err) {
                return console.log(err)
            }


            console.log('Message sent: %s', info.message)
            // console.log('Message URL: %s', nodemailer.getTestMessageUrl(info))
        })
    })
})

const PORT = process.env.PORT || 3001;

if (process.env.NODE_ENV === 'production') {
    // Serve any static files
    app.use(express.static(path.join(__dirname, 'client/build')));

    // Handle React routing, return all requests to React app
    app.get('*', function(req, res) {
      res.sendFile(path.join(__dirname, 'client/build', 'index.html'));
    });
  }

app.listen(PORT, () => {
    console.log(`Server listening on port ${PORT}`);

})

At the same time, if you look in the console in the index.js file (which is in the src folder), then the variables are displayed with the desired value

Answer 1

If I saw it correctly, the files are like this:
, and by default dotenv searches .envin the current directory, if not reassigned, judging by the description .
I will assume that it index.jswas launched from ./client, but server.js, say, from the folder where it is located.
UPD Spoiler: .envI was not in CWD, it helped to indicate the path to it throughdotenv.config({ path: … })