如何在 Node.js 中设置 dotenv 文件？

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i didn't put my environment variables in the right format as was in the dotenv module documentation e.g. i was doing export TWILIO_CALLER_ID="+wwehehe" and so the dotenv module wasn't parsing my file correctly. When i noticed that i removed the export keyword from the declarations and everything worked fine.

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I solved this using:

require('dotenv').config({path: __dirname + '/.env'})

or with an absolute path:

C:\\asd\\auhsd\\.env

If it does not find the .env file, it will return undefined.

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In my case, every time I tried to get a key from the .env file using process.env.MY_KEY, it returned undefined.

I suffered from this problem for two hours just because I named the file something like keys.env which is not considered to be a .env file.

So here is the troubleshooting list:

The filename should be .env (I believe .env.test is also acceptable).
Make sure you are requiring it as early as possible in your application using this statement require('dotenv').config();
The .env file should be in the root directory of your project.
Follow the "file writing rules" like DB_HOST=localhost, no need to wrap values in double/single quotes.

Also, check the documentation of the package on the NPM site.

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I had the same problem and I tried 4 hours to find the fault. In my case, it was bizarre.

When I tried "node app.js", it worked. When I wanted a daemon to start it, it did not work.

How did I solve my problem? I replaced:

var dotenv = require('dotenv');
dotenv.load();

with:

var dotenv = require('dotenv').config({path: path.join(__dirname, '.env')})

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My problem was stupid. I created the .env in a text editor, and when I saved it it actually saved as

'.env.txt'

which was only visible after I did a

'ls -a'

in terminal and saw the file name.

A quick:

mv .env.txt .env

And I was in business

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Take care that you also execute your Node script from the ROOT folder.

E.g. I was using a testing script in a subfolder called ./bin/test.js. Calling it like: node ./bin/test.js worked totally fine. Calling it from the subfolder like:

$ pwd
./bin
$ node ./test.js

causes dotenv to not find my ./.env file.

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Had the same issue recently. Check your .env file and use equal sign not colon. Here's an example:

key=value

instead of:

key:value

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Make sure to set cwd in the pm2 config to the correct directory for any calls to dotenv.config().

Example: Your index.js file is in /app/src, your .env file is in /app. Your index.js file has this

dotenv.config({path: "../.env"});

Your pm2 json config should have this: "cwd": "/app/src", "script": "index.js"

You could also use dotenv.config({path: path.join(__dirname, "../.env")}); to avoid the CWD issue. You will still have a problem if you move the .env or the index.js file relative to each other.

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Make sure that variables are not already set. Dotenv won't override them.

If variables are set then you will have to remove them. In powershell you can use the following command - as mentioned here:

Remove-Item Env:\MyTestVariable

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Had the same problem. I used dotenv-webpack and need to define

plugins: [
new Dotenv()
]

in both webpack production and webpack base files (I use webpack merge). If was not defined in both files then it did not work.

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I had the same problem. I realized my file was somehow encoded in UCS-2 BE BOM. Converting my .env file to UTF-8 fixed it (you can easily do that using Notepad++, for example).

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The '.env' file should be in the root directory of your node js server file (server.js or for me).

If you placed the '.env' file at the root of your project, it won't work. My mistake was that I have the server.js file nested in a folder named 'controller'.

So I had to fix it by placing the .env file in the same directory as the server.js file.

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I had a problem also with .env variables not loading and being undefined.

What I tried:

index.js:

import dotenv from 'dotenv';
dotenv.config();
import models from './models';

models.js

import Sequelize from 'sequelize';
const sequelize = new Sequelize(
process.env.DATABASE,
process.env.DATABASE_USER,
process.env.DATABASE_PASSWORD,
{
dialect: 'postgres',
}
);

Apparently, because of how loading the imports works in nodejs, the import of models in index.js caused that the models.js was executed before dotenv.config(). Therefore I got undefined values from process.env.

When I changed models.js to do the dotenv configuration like:

import Sequelize from 'sequelize';
import dotenv from 'dotenv';
dotenv.config();
const sequelize = new Sequelize(
process.env.DATABASE,
process.env.DATABASE_USER,
process.env.DATABASE_PASSWORD,
{
dialect: 'postgres',
}
);

it started to work!

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Save yourself some troubleshooting time and log your require call, like so:

console.log(require('dotenv').config())

You should see an error with more detailed info on the problem.

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In my case, I've created a wrapper JS file in which I have the logic to select the correct variables according to my environment, dynamically.

I have these two functions, one it's a wrapper of a simple dotenv functionality, and the other discriminate between environments and set the result to the process.env object.

setEnvVariablesByEnvironment : ()=>{
return new Promise((resolve)=>{


if (process.env.NODE_ENV === undefined || process.env.NODE_ENV ==='development'){
logger.info('Lower / Development environment was detected');


environmentManager.getEnvironmentFromEnvFile()
.then(envFile => {
resolve(envFile);
});


}else{
logger.warn('Production or Stage environment was detected.');
resolve({
payload: process.env,
flag: true,
status: 0,
log: 'Returned environment variables placed in .env file.'
});
}




});
} ,


/*
Get environment variables from .env file, using dotEnv npm module.
*/
getEnvironmentFromEnvFile: () => {
return new Promise((resolve)=>{
logger.info('Trying to get configuration of environment variables from .env file');


env.config({
debug: (process.env.NODE_ENV === undefined || process.env.NODE_ENV === 'development')
});


resolve({
payload: process.env,
flag: true,
status: 0,
log: 'Returned environment variables placed in .env file.'
});
});
},

So, in my server.js file i only added the reference:

const envManager = require('./lib/application/config/environment/environment-manager');

And in my entry-point (server.js), it's just simple as use it.

envManager.setEnvVariablesByEnvironment()
.then(envVariables=>{
process.env= envVariables.payload;


const port = process.env.PORT_EXPOSE;
microService.listen(port, '0.0.0.0' , () =>{


let welcomeMessage = `Micro Service started at ${Date.now()}`;
logger.info(welcomeMessage);


logger.info(`${configuration.about.name} port configured  -> : ${port}`);
logger.info(`App Author: ${configuration.about.owner}`);
logger.info(`App Version: ${configuration.about.version}`);
logger.info(`Created by: ${configuration.about.author}`);


});
});

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I had to literally use no name for the .env file, just have the .env extension and save the file like that and it worked.

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I solved this just renaming the file to .env to y file was named config.env , when I renamed to .env , it works.

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If you are facing this problem it could be that the environment variable(s) is added/loaded after the file that requires the specific variable

const express = require('express');


const app = express();
const mongoose = require('mongoose');
const dotenv = require('dotenv');
const morgan = require('morgan');


const passport = require('passport'); //you want to use process.env.JWT_SECRET (you will get undefined)


dotenv.config();

in the above case, you will get undefined for the process.env.JWT_SECRET

So the solution is that you put dotenv.config() before const passport = require('passport');

const express = require('express');


const app = express();
const mongoose = require('mongoose');
const dotenv = require('dotenv');
const morgan = require('morgan');
dotenv.config();
const passport = require('passport'); //you want to use process.env.JWT_SECRET (you will get the value for the enviroment variable)

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I spent a lot of time going through these fixes. I was developing locally and just had to restart the server because the .env file isn't hot reloaded.

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For React apps created with the create-react-app template, you don't need to use dotenv directly. react-scripts does that for you.

Simply creates a .env file in the top level directory of your project and add all your envs there, but notice that they MUST start with REACT_APP prefix, otherwise they will be ignored.

More details in their documentation. I just spent a couple of hours dealing with this and hope it will save you some time.

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I am using NodeJS on windows 10. I used process.env.var-name to access the variables but failed because it gives me windows path variables as a JSON object, so I installed dotenv ( npm install dotenv ). dotenv gets process envirnoment variables from your project's .evn file

npm install dotenv or yarn add dotenv

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

process.env.variable_name

output

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is dotenv installed in your project?

Try to install it using npm install dotenv in your project.

Once it is installed load it in any files where you need it using const env = require('dotenv').config().

You can then use in any line where you need to. For example to call port from .env use: process.env.PORT

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If you use "firebase-functions" to host your sever-side-rendered application, you should be aware of this one:

error: Error: ENOENT: no such file or directory, open 'C:\Codes\url_shortener\functions\.env'

Means you have to store the .env file in the functions folder as well.

Found this one by:

console.log(require('dotenv').config())

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I cloned a repo from Github and went through every one of the suggestions here. After a lot of frustration, I realized that npm install did not install any of the modules and my node_modules folder was empty the whole time.

QUICK FIX:
1) delete your node_modules folder
2) delete your package-lock.json
3) run npm install

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const dotenv = require('dotenv'),
path   = require('path')
dotenv.config({path: path.join(__dirname, '../.env')})

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Working Solution:

If you are using webpack (which you definitely should), use a very handy plugin dotenv-webpack which solves the issue of reading environment variables from .env file

Make sure .env is in root directory of your project.

Steps to install the plugin:

npm i -D dotenv-webpack
In webpack.config file:

     const Dotenv = require('dotenv-webpack');
module.exports = {
...
plugins: [
new Dotenv(),
...
],
...
};

Now you can call any environment variable defined in .env file using process.env in any js file

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I had the same problem. I had created a file named .env, but in reality the file ended up being .env.txt.

I created a new file, saved it in form of 'No Extension' and boom, the file was real .env and worked perfectly.

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My code structure using is as shown below

-.env
-app.js
-build
-src
|-modules
|-users
|-controller
|-userController.js

I have required .env at the top of my app.js

require('dotenv').config();
import express = require('express');
import bodyParser from 'body-parser';
import mongoose = require('mongoose');

The process.env.PORT works in my app.listen function. However, on my userController file not sure how this is happening but my problem was I was getting the secretKey value and type as string when I checked using console.log() but getting undefined when trying it on jwt.sign() e.g.

console.log('Type: '+ process.env.ACCESS_TOKEN_SECRET)
console.log(process.env.ACCESS_TOKEN_SECRET)

Result:

string
secret

jwt.sign giving error

let accessToken = jwt.sign(userObj, process.env.ACCESS_TOKEN_SECRET); //not working

Error was

    Argument of type 'string | undefined' is not assignable to parameter of type 'Secret'.
Type 'undefined' is not assignable to type 'Secret'.

My Solution: After reading the documentation. I required the env again in my file( which I probably should have in the first place ) and saved it to variable 'environment'

let environment = require('dotenv').config();

console logging environment this gives:

{
parsed: {
DB_HOST: 'localhost',
DB_USER: 'root',
DB_PASS: 'pass',
PORT: '3000',
ACCESS_TOKEN_SECRET: 'secretKey',
}
}

Using it on jwt.sign not works

let accessToken = jwt.sign(userObj, environment.parsed.ACCESS_TOKEN_SECRET);

Hope this helps, I was stuck on it for hours. Please feel free to add anything to my answer which may help explain more on this.

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On some operating sytems (mostly some linux distros, I am looking at you raspbian), .env files don't work. rename them and import that

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I've noticed something here myself.

I've defined .env correctly, etc and i'd defined DATABASE_URL in there but despite doing so another DATABASE_URL was being referenced, perhaps a global environment variable is referenced if it exists?

Anyhow, I found that when I defined TEST and CONNECTION_STRING within .env these both were referenced correctly where as DATABASE_URL continues to not be.

Thanks,

Michael

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This is how i fix my issue

Intially had this in .env of the root of my project

const db_port = 90101
const db_host="localhost"
const db_username="name"
const db_password="pwd"
const db_name="db"

And all my env variables where undefined.

I fixed it by removing all the const and using just key=value insted of const key="value"

db_port = 90101
db_host=localhost
db_username=name
db_password=pws
db_name=db

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There's a lot of confusion about this topic and in these answers. I'm not surprised, that no single answer was accepted. Hopefully yet.

The answer by Basheer indeed solves most of the problems. However, there are few things you still need to know. Especially, if you're coming, like me, from frontend background and wants to add secrets to your frontend. Possibly, related to the introduction of some Server-Side Rendering (SSR) logic in the app.

Most probably you've seen this code in your webpack settings in a frontend app to solve the issue, as a frontend developer.

/* Custom webpack properties. */
const dotenv = require('dotenv-webpack');


module.exports = {
plugins: [
new dotenv(), // Handle environemntal variables on localhost, but on the Server-Side Rendering (SSR). There's no access to "process.env" on the browser.
],
};

Now, it'll work out fine, if you render on the server (SSR) across your app if the .env file is in the root of your project. Nuxt.js0 An example of such situation is Angular Universal, Nuxt.js handles this much easier in which require('dotenv').config() in your next.config.js and makes you good to go. That's due to difference in philosophies between how Angular and Vue.js are handling SSR. To get Angular Universal app from Angular that's just 1 command, but the SSR app isn't as nicely organized as Nuxt.js. It comes with a price that to generate Nuxt.js app from Vue.js, you basically have to generate a new Nuxt.js project and copy files due to quite some differences between Nuxt.js and Vue.js setup. Don't know how Angular Universal5/Angular Universal6 and Angular Universal7/Angular Universal8 solves this, but if similarly to Angular then you also might consider reading further.

Now, you've some server-related logic in a separated folder called server and let say the file is called main.ts. Maybe apart SSR in that file, you can also have sending mail (nodemailer?) logic. Then you'd like to use process.env, but apparently it doesn't work, even though you have the logic defined in webpack. That's where the require('dotenv').config(); is needed, even if you're using different syntax for import (such as import { Express } from 'express'; for example), require('dotenv').config(); will work like that. Don't feel confused. As long as .env is in the root of your app (don't confuse with server folder) and the variables have correct syntax inside that file, e.g.

MAIL_ACCOUNT=mymail@mydomain.com
MAIL_HOST=smtp.mydomain.com
MAIL_PORT=587

It'll work.

Last scenario, in the SSR app you realised that to host this app you need something called Serverless/Cloud Functions/FaaS. Here, I know only Firebase scenario. In your project, to deploy such app you might have functions folder, from which you deploy the SSR app to the Cloud Functions for Firebase, in this example. What a surprise, on a deployment mail is not working and after hours of figuring out what's happening in the logs you can see process.env.VARIABLE_NAME returning undefined. The reason is that as of today the CLI cannot merge files from other locations and indeed the .env file has to be manually copied to the functions folder. Once copy/paste the .env file to functions and deploy, it'll work.

What you can use for debugging is one of those:

console.log(require('dotenv').config());
console.log(require('dotenv').config({debug: true}));

However, be careful with your secrets, because these will be revealed when your .env setup will be done. Trying to access one of the secrets and trying to log its value in the logs might be more secure option. Especially, if you have many secrets and don't want to rewrite all.

Hope so this one post will cover most of the scenarios.

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In my case, I was creating a vscode extension in which __dirname was referring to something like d:\extension\my_extension\out.

the root folder was my_extension, but __dirname was pointing to my_extension\out

so I fixed it by writing

require('dotenv').config({path: __dirname.slice(0,-3)+'/.env'});

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i had similar problem. i solved it by trim. Please check, path.resolve may add additional space to end of path.

var path = require('path');
const envPath = path.resolve(process.cwd()+'/config','.env.'+process.env.NODE_ENV).trim()
require('dotenv').config({ path: envPath })

my package script is like this to use multiple .env:

 "scripts": {
"start": "set NODE_ENV=development && nodemon ./bin/www",
"prod": "set NODE_ENV=production && node ./bin/www"
},

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In my case, the same codebase that reads my .env file on my MacBook Pro didn't read the .env file on my staging server ubuntu 18.04, so i tried @user3006381 advice and i noticed the code is trying to look for .env file in my user directory "/home/myusername/.env" and not in "/home/myusername/project/.env", if you have any idea why that is happening please add a comment.

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If this is a react native project using dotenv, the .env file might not change because it's being cached in an IOS build. In XCode, do a Product > Clean Build Folder every time you update the .env

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var dotenv = require('dotenv').config({path: 'D:\\site-checker\\.env'});
console.log(dotenv);
result---
{
parsed: {
PORT: '5000',
HOST: 'http://localhost',
DATABASENAME: 'test_sitechecker',
NODE_ENV: 'test'
}
}

Here what I struggled with is my path was wrong, it should with two backslashes and should point exactly where your .env file is.

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I faced the same problem when I moved my server code to a nested folder since dotenv is looking in the root directory by default. On top of that, I was using using ES6 module imports so I had to do the following:

import dotenv from "dotenv";
dotenv.config({ path: "/path/to/envfile/.env" };

It did the trick in my case. As an extra tip, in case you want to use __dirname to get the path, if you had set

type: "module"

in your package.json file like I did, you won't be able to use __dirname. What I did, was to go to the directory where .env file was and create a new file named envpath.cjs (pay attention to .cjs):

// envpath.cjs
// a file to return the path as a string


const envpath = __dirname;
module.exports = envpath;

Then in my working module I had:

import dotenv from "dotenv";
import envpath from "../envpath.cjs";
dotenv.config({path: envpath + "/.env"});