Different env variables for testing and development in nodejs

Question

I'm developing a nodejs api in my free time, and I'm trying to implement testing now. I'm currently loading my environment variables from a.env file (loaded using dotenv ), which include the DB_URI , DB_USER and DB_PASSWORD for my development mongodb database.

Now, I would like to create a separate database for testing however I don't know how would I load different variables to connect to the testing database instead of the development database. I deploy to Heroku where I have different environment variables so that's covered just fine.

I've tried to find online for some answers for best practices, but I have been unable to. I thought of creating a different.env file, however that's not recommended according to the documentation on npmjs. .

Other resources recommended recommended hard coding the specific variables I needed in the package.json script. However, the script would be huge if I had to change all the variables needed to connect to a different database.

Can I get some help understanding how I should do this?

Thanks!

PS: In case it's needed, I'm using mocha and supertest for my tests.

Answer 1

1. In your .env file, add variables for each environment:

    DB_URI_DEVELOPMENT="https://someuri.com" DB_USER_DEVELOPMENT=someuser DB_PASSWORD_DEVELOPMENT=somepassword DB_URI_TEST="https://otheruri.com" DB_USER_TEST=otheruser DB_PASSWORD_TEST=otherpassword

2. Start the application in development :

    NODE_ENV=development node server.js

   or in test :

    NODE_ENV=test node server.js

3. Access the environment variables for this environment:

    // don't try to load .env file on Heroku if (process.env.NODE_ENV !== 'production') { require('dotenv').config() } // get the current environment var env = process.env.NODE_ENV // convert to uppercase var envString = env.toUpperCase() // access the environment variables for this environment var dbUri = process.env['DB_URI_' + envString] var dbUser = process.env['DB_USER_' + envString] var dbPassword = process.env['DB_PASSWORD_' + envString]

Hope that helps!

Answer 2

Personally I like having the same environment variable names for different environments, so I created a env.ts to include where I want to load my dotEnv so I can use the same environment variable names throughout my application.

import * as process from "process";
import * as dotenv from 'dotenv'
import * as path from "path";

const getDotEnvPath = (env?: string) => {
    if (env == 'TEST') {
        return '.env.test'
    }
    return '.env'
}
dotenv.config({path: path.resolve(process.cwd(), getDotEnvPath(process.env.NODE_ENV?.toUpperCase()))})

Its also good to note that by default dotEnv only sets the environment variables when they are not already set.