/Javascript/Node.js/Node process.env.PORT

Node process.env.PORT

In many environments (e.g. Heroku), and as a convention, 
you can set the environment variable PORT 
to tell your web server what port to listen on.

So `process.env.PORT || 3000` means: 
whatever is in the environment variable PORT, 
or 3000 if there's nothing there.

So you pass that to app.listen, 
or to app.set('port', ...), 
and that makes your server able to accept a 
"what port to listen on" parameter from the environment.

If you pass 3000 hard-coded to app.listen(), 
you're always listening on port 3000, 
which might be just for you, or not, 
depending on your requirements and the requirements of the environment 
in which you're running your server.

Source: stackoverflow.com

Similar codes

0 vote110 views1 answer
React and node js sample project github
Javascript Node.js
0 vote101 views2 answers
Cannot find namespace 'NodeJS'.
Javascript Node.js
-4 votes109 views5 answers
Nodejs
Javascript Node.js
1 vote109 views1 answer
Javascript find diff in nested objects node js
Javascript Node.js
0 vote108 views1 answer
Nodejs console.log timestampt
Javascript Node.js
0 vote115 views1 answer
How to check if a folder exists in node js
Javascript Node.js
2 votes102 views1 answer
Promise method in node js
Javascript Node.js
91 votes206 views4 answers
How to install node js 14 on ubuntu
Javascript Node.js
0 vote102 views1 answer
Node equivalent of bash exec
Javascript Node.js
0 vote102 views1 answer
How to detech ctrl+C exist in nodejs
Javascript Node.js