onstdin

Calls back on chuncks read via the standard input (stdin). (Synchroneously but non blocking)

Installation

$ npm install onstdin

Usage

Example : Create two scripts : myScript.mjs and myOtherScript.mjs

// myScript.mjs

const options = { param1:'hello', param2:'world' }

console.log(JSON.stringify(options,null,2))

// myOtherScript.mjs

import { onstdin } from "onstdin";

onstdin((content) => {
	if(content) {
		const { param1, param2 } = JSON.parse(content ? content : "{}");
		console.log(`${param1} ${param2} onstdin`);
	} else {
		console.log("BOOM !");
	}
});

Execute a pipline via a node commande

$ node ./myScript.mjs | ./myOtherScript.mjs

Output

> hello world onstdin

Complience

When nothing is passed through the stdin, a null value is passed. but the pipe is not blocked.

Example

$ node ./myScript.mjs | ./myOtherScript.mjs
> hello world onstdin

Executing the script without the first step will pass null in to myOtherScript.mjs.

$ node ./myOtherScript.mjs
> BOOM !

Force blocking

When the -F or --force argument are passed the waiting for a chunk to be read to the end of a stream is enforced.

$ node ./myOtherScript.mjs -F
> 

API

onstdin(cb:() => void, enc:string = 'utf8'): void

| Parameters | description | | ---------- | ------------------------------------------------------ | | cb | the callback function | |enc| the encoding (utf8 by default)|

License

MIT