angular-cli server - how to specify default port

Question

Using angular-cli with the ng serve command, how can I specify a default port so I do not need to manually pass the --port flag every time?

Answer 1

There might be a situation when you want to use NodeJS environment variable to specify Angular CLI dev server port. One of the possible solution is to move CLI dev server running into a separate NodeJS script, which will read port value (e.g from .env file) and use it executing ng serve with port parameter:

// run-env.js
const dotenv = require('dotenv');
const child_process = require('child_process');

const config = dotenv.config()
const DEV_SERVER_PORT = process.env.DEV_SERVER_PORT || 4200;

const child = child_process.exec(`ng serve --port=${DEV_SERVER_PORT}`);
child.stdout.on('data', data => console.log(data.toString()));

Then you may a) run this script directly via node run-env, b) run it via npm by updating package.json, for example

"scripts": {
  "start": "node run-env"
}

run-env.js should be committed to the repo, .env should not. More details on the approach can be found in this post: How to change Angular CLI Development Server Port via .env.