read.js

/*property
    clearLine, close, createInterface, empty_array, forEach, freeze, hidden,
    input, length, line, moveCursor, on, output, prompt, setPrompt, stdin,
    stdout, write
*/

import readline from "readline";
import utils from "./utils.js";

const {empty_array} = utils;

function read(callback, prompt, options = {}) {
    const input = options.input || process.stdin;
    const output = options.output || process.stdout;
    const hidden = options.hidden || false;
    prompt = prompt || "";

    const rl = readline.createInterface({
        input,
        output
    });

    // hide the inserted input value with the asterisk replacement
    // taken from https://stackoverflow.com/questions/24037545/how-to-hide-password-in-the-nodejs-console
    // I've found this solution a better option than muting a stream
    if (hidden === true) {
        rl.input.on(
            "keypress",
            function () {
                // get the number of characters entered so far:
                const len = rl.line.length;
                // move cursor back to the beginning of the input:
                readline.moveCursor(rl.output, -len, 0);
                // clear everything to the right of the cursor:
                readline.clearLine(rl.output, 1);
                // replace the original input with asterisks:
                empty_array(len).forEach(function () {
                    rl.output.write("*");
                });
            }
        );
    }

    rl.setPrompt(prompt);
    rl.prompt();

    rl.on(
        "line",
        function (input) {
            rl.close();
            callback(input);
        }
    );

    rl.on(
        "error",
        function (error) {
            rl.close();
            callback(undefined, error);
        }
    );
}

export default Object.freeze(read);