Can't use dotenv with ES6 modules

Question

I am moving an Express app across from CommonJS require syntax to the ES6 module import syntax. This is fine until I try and use dotenv to load my environment variables and every time I try to access these variables they come back as undefined.

app.js

// importing environmental variables
import dotenv from 'dotenv';
dotenv.config();
import express from 'express';

let x = process.env.David;
console.log(x);

.env

David = test

Answer 1

import "dotenv/config.js";

对于所有文件中的.env变量，请使用上述内容。

Answer 2

Try putting the env config in a separate file and import it first.

// loadEnv.js
import dotenv from 'dotenv';
dotenv.config()


// index.js
import './loadEnv';
import express from 'express';
let x = process.env.David;
console.log(x);

Answer 3

 // importing environmental variables
        import express from 'express';
        import { config } from "dotenv";
        config({ path: process.ENV })
            
        let x = process.env.David;
        console.log(x);

Answer 4

import path from 'path';
import { fileURLToPath } from 'url';
import "dotenv/config.js";
    
const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

dotenv.config({path:`${__dirname}/.env`});

I did this because my.env file was inside src folder (projectName/src/.env) and it was not detected by dotenv. But actually it's easier move.env file to the project folder (projectName/.env) and use:

import "dotenv/config.js";