NodeJS: How To Talk/Answer To The Terminal

Intro

So we installed NodeJS on our machine.

Now we want to write a simple script, run it from the terminal & talk/answer to the terminal

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Write a simple script

• Open your terminal
• Create a file named index.js:

touch index.js

• Add this JavaScript code into it:

process.stdout.write("What's your name?\n");

process.stdin.on('readable', () => {
  const userInput = process.stdin.read();
  process.stdout.write(`Your Input was: ${userInput}`);
});

Note: I removed all "unnecessary" stuff from the documentation to decrease the complexity of this simple example.

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Every line decoded

// writes something to the stdout (your terminal), including a newline at the end
process.stdout.write("What's your name?\n");

Console.log() uses stdout under the hood.

// if a specific event (here: a readable stream) happens, then run this  callback
process.stdin.on('readable', () => {...});

Documentation for readable stream

// read data from the stream & save it into a variable
  const userInput = process.stdin.read();

// writes something to the stdout
  process.stdout.write(`Your Input was: ${userInput}`);

Run it from the terminal

• Run it:

node index.js

• Result:

What`s your name?
miku86
Your Input was: miku86

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Questions

• Do you use the native process.stdin or some libraries like inquirer or prompts? Why?