README.md

promptly

---

Simple command line prompting utility.

Installation

$ npm install promptly

API

In all the commands, the options argument is not mandatory.

.prompt(message, opts, fn)

Prompts for a value, printing the message and waiting for the input.
When done, calls fn with error and value.

Default options:

{
    // The default value to assume. If not supplied, the input is mandatory
    'default': 'default value',
    // Automatically trim the input
    'trim': true,
    // A validator or an array of validators.
    'validator': null,
    // Automatically retry if a validator fails
    'retry': false,
    // Do not print what the user types
    'silent': false,
    // Input and output streams to read and write to
    'input': process.stdin,
    'output': process.stdout
}

The validators have two purposes:

function (value) {
    // Validation example, throwing an error when invalid
    if (value.length !== 2) {
        throw new Error('Length must be 2');
    }

    // Parse the value, modifying it
    return value.replace('aa', 'bb');
}

Example usages

Ask for a name:

promptly.prompt('Name: ', function (err, value) {
    // err is always null in this case, because no validators are set
    console.log(value);
});

Ask for a name with a constraint (non-empty value and length > 2):

var validator = function (value) {
    if (value.length < 2) {
        throw new Error('Min length of 2');
    }

    return value;
};

promptly.prompt('Name: ', { validator: validator }, function (err, value) {
    if (err) {
        console.error('Invalid name');
        // Manually call retry
        // The passed error have a retry method to easily prompt again.
        err.retry();
    }

    console.log('Name is: ', value);
});

Same as above but retry automatically:

var validator = function (value) {
    if (value.length < 2) {
        throw new Error('Min length of 2');
    }

    return value;
};

promptly.prompt('Name: ', { validator: validator , retry: true}, function (err, value) {
    // err is always null because promptly will be prompting for a name until it validates
    console.log('Name is: ', value);
});

.confirm(message, opts, fn)

Ask the user to confirm something.
Calls fn with error and value (true or false).

The available options are the same, except that retry defaults to true.
Truthy values are: y, yes and 1. Falsy values are n, no, and 0. Comparison is made in case insensitive way.

Example usage:

promptly.confirm('Are you sure? ', function (err, value) {
    console.log('Answer: ', value);
});

.choose(message, choices, opts, fn)

Ask the user to choose between multiple choices (array of choices).
Calls fn with error and value (true or false).

The available options are the same, except that retry defaults to true.

Example usage:

promptly.choose('Do you want an apple or an orange? ', ['apple', 'orange'], function (err, value) {
    console.log('Answer: ', value);
});

.password(message, opts, fn)

Prompts for a password, printing the message and waiting for the input.
When available, calls fn with error and value.

The available options are the same, except that trim and silent defaults to false.

Example usage:

promptly.password('Type a password: ', function (err, value) {
    console.log('Password is', value);
});

License

Released under the MIT License.