Let's see how to use params in NPM scripts that you setup in your package.json and how to read this variables in your scripts

🛠 Setup in package.json

In order to run a script with a command like npm run myscript you should add the next line in the scripts block of your package.json:

"scripts": {
  "myscript": "./bin/myscript.js run=true"
}

👨‍💻 How to read params

In the ./bin/myscript.js file, you can read the params with process.argv that contains:

 [ 
  "node",  
  "/Users/dburgos/code/npm-params/bin/myscript.js",
  "run=true"
 ]

So you can access it as following:

const parameter = process.argv[2]; // "run=true"
const runValue = parameter.split('=')[1]; // "true"

💡 Please note you will get them as strings

Another example 👇

If you set a parameter like --delete true:

"scripts": {
  "myscript": "./bin/myscript.js --delete true"
}

⚠️ Note the space between both.

You will get them as following:

 [ 
  "node",  
  "/Users/dburgos/code/npm-params/bin/myscript.js",
  "--delete",
  "true",
 ]

Then you will get:

const parameter = process.argv[2]; // "--delete"
const value = process.argv[3]; // "true"

Leave comment with your questions or doubts, happy yo help you 🙂
👋 Thanks for reading!