A NodeJS mini-module-thing that allows fairly simple handling of command-line commands for your server

clicommands.js

((initialCommands, undefined) => {
    const readline = require('readline');

    let commands = typeof initialCommands !== 'object' ? {} : initialCommands;

    function replaceCommand(name, func) {
        commands[name] = [func];
    }

    function addCommand(name, func) {
        if (commands.hasOwnProperty(name)) {
            commands[name].append(func);
        } else {
            commands[name] = [ func ];
        }
    }

    function addAllCommands(kvps) {
        for (var prop in kvps) {
            if (kvps.hasOwnProperty(prop)) {
                addCommand(prop, kvps[prop]);
            }
        }
    }

    function removeCommand(name, func = undefined) {
        if (typeof func === 'undefined') {
            delete commands[name];
        } else {
            let list = commands[name];
            let rmIdx = list.indexOf(func);
            if (rmIdx >= 0) list.splice(rmIdx, 1);
        }
    }

    module.exports = {
        replaceCommand,
        addCommand,
        addAllCommands,
        removeCommand
    };

    const stdin = readline.createInterface({
        input: process.stdin,
        output: process.stdout
    });
    stdin.on('line', (line) => {
        var args = line.trim().split(' ', 2);
        if (args[0] === 'help' || args[0] === '?') {
            console.log('The following commands are available:');
            console.log('- help (or ?)');
            for (var prop in commands) {
                if (commands.hasOwnProperty(prop)) {
                    console.log('- %s', prop);
                }
            }
        } else if (commands.hasOwnProperty(args[0])) {
            commands[args[0]].forEach(e => e(args[1]));
        } else {
            console.log("Invalid command. Type `help` to get a list of commands.");
        }
    });
})();