javascript - How to hide password in the nodejs console?

Question

I want to hide password input. I see many answers in stackoverflow but I can't verify value if I press backspace. The condition return false.

I tried several solution to overwrite the function but I got an issue with buffer if I press backspace, I got invisible character .

I press : "A", backspace, "B", I have in my buffer this : "u0041u0008u0042" (toString() = 'AB') and not "B".

I have :

var readline = require('readline');

var rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
});

rl.question("password : ", function(password) {
    console.log("Your password : " + password);
});

Answer 1

This can be handled with readline by intercepting the output through a muted stream, as is done in the read project on npm (https://github.com/isaacs/read/blob/master/lib/read.js):

var readline = require('readline');
var Writable = require('stream').Writable;

var mutableStdout = new Writable({
  write: function(chunk, encoding, callback) {
    if (!this.muted)
      process.stdout.write(chunk, encoding);
    callback();
  }
});

mutableStdout.muted = false;

var rl = readline.createInterface({
  input: process.stdin,
  output: mutableStdout,
  terminal: true
});

rl.question('Password: ', function(password) {
  console.log('
Password is ' + password);
  rl.close();
});

mutableStdout.muted = true;