How to set process.env from the file in NodeJS?

Question

I\'m new to the Node.JS. I found few articles says we can use .env file to setup the process.env variable, e.g.,

PORT = 8081

but when I run

Answer 1

Dotenv file have become the most popular mode to separate configuratione from app, using system environment variables (see 12factor config).

On node there exists a lot of libraries for loading config from .env file. The most popular is motdotla/dotenv. You can read a lot of examples on readme file about the usage of this library