在gulp-nodemon中设置端口有什么用？

Question

I am using gulp-nodemon because of its most obvious of utilities.

Nodemon is a utility that will monitor for any changes in your source and automatically restart your server.

But I am not understanding a practice which seems to be prevalent in express/node development.

I just started working with node and express but from what I understand:

app.js

var express = require('express'),
    app = express(),
    port = process.env.PORT || 8016;


app.get('/', function rootHndlr(req, res) {
    /* body... */
    res.send('welcome to my API!');
});

app.listen(port, function listenHndlr(){
    console.log('Gulp is running my app on PORT ' + port);
});

The following is setting in the port to 8016 if not set.

port = process.env.PORT || 8016;

So now we binds and listens for connections on the specified host and port.

But then I see people configure in their gulp tasks the following to nodemon in their gulpfile.js

gulpfile.js

var gulp = require('gulp'),
    nodemon = require('gulp-nodemon');

gulp.task('default', function() {
    // content
    nodemon({
        script: 'app.js',
        ext: 'js'
        env: {
            PORT: 8000
        },
        ignore: ['./node_modules/**']
    }).
    on('restart', function(){
        consile.log('Restarting');
    });
});

As you can one of the values in nodemon env: {PORT: 8000} Why set the port again?

Thanks!

Answer 1

People are using something like that as a fallback: port = process.env.PORT || 8016; port = process.env.PORT || 8016;

Your application should be flexible enough and by passing an env var to make it listen to another port. In general, this is the purpose of the env vars.

About your example, I suppose that there is a reason that the guy that wrote this gulpfile would like to make the app listen to port 8000. I would say that it is safe to change the value or to remove the PORT: 8000 as soon as you are 100% sure that there is no reason that the application needs to run on port 8000 (for example, it is behind a reverse proxy that forwards the traffic to port 8000).