motion
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motion - moving development forward
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# prompt [](http://travis-ci.org/flatiron/prompt)
A beautiful command-line prompt for node.js
## Features
* prompts the user for input
* supports validation and defaults
* hides passwords
## Usage
Using prompt is relatively straight forward. There are two core methods you should be aware of: `prompt.get()` and `prompt.addProperties()`. There methods take strings representing property names in addition to objects for complex property validation (and more). There are a number of [examples][0] that you should examine for detailed usage.
### Getting Basic Prompt Information
Getting started with `prompt` is easy. Lets take a look at `examples/simple-prompt.js`:
``` js
var prompt = require('prompt');
//
// Start the prompt
//
prompt.start();
//
// Get two properties from the user: username and email
//
prompt.get(['username', 'email'], function (err, result) {
//
// Log the results.
//
console.log('Command-line input received:');
console.log(' username: ' + result.username);
console.log(' email: ' + result.email);
});
```
This will result in the following command-line output:
```
$ node examples/simple-prompt.js
prompt: username: some-user
prompt: email: some-user@some-place.org
Command-line input received:
username: some-user
email: some-user@some-place.org
```
### Prompting with Validation, Default Values, and More (Complex Properties)
In addition to prompting the user with simple string prompts, there is a robust API for getting and validating complex information from a command-line prompt. Here's a quick sample:
``` js
var schema = {
properties: {
name: {
pattern: /^[a-zA-Z\s\-]+$/,
message: 'Name must be only letters, spaces, or dashes',
required: true
},
password: {
hidden: true
}
}
};
//
// Start the prompt
//
prompt.start();
//
// Get two properties from the user: email, password
//
prompt.get(schema, function (err, result) {
//
// Log the results.
//
console.log('Command-line input received:');
console.log(' name: ' + result.name);
console.log(' password: ' + result.password);
});
```
Pretty easy right? The output from the above script is:
```
$ node examples/property-prompt.js
prompt: name: nodejitsu000
error: Invalid input for name
error: Name must be only letters, spaces, or dashes
prompt: name: Nodejitsu Inc
prompt: password:
Command-line input received:
name: Nodejitsu Inc
password: some-password
```
## Valid Property Settings
`prompt` understands JSON-schema with a few extra parameters and uses [revalidator](https://github.com/flatiron/revalidator) for validation.
Here's an overview of the properties that may be used for validation and prompting controls:
``` js
{
description: 'Enter your password', // Prompt displayed to the user. If not supplied name will be used.
type: 'string', // Specify the type of input to expect.
pattern: /^\w+$/, // Regular expression that input must be valid against.
message: 'Password must be letters', // Warning message to display if validation fails.
hidden: true, // If true, characters entered will not be output to console.
default: 'lamepassword', // Default value to use if no value is entered.
required: true // If true, value entered must be non-empty.
before: function(value) { return 'v' + value; } // Runs before node-prompt callbacks. It modifies user's input
}
```
Alternatives to `pattern` include `format` and `conform`, as documented in [revalidator](https://github.com/flatiron/revalidator).
Using `type: 'array'` has some special cases.
- `description` will not work in the schema if `type: 'array'` is defined.
- `maxItems` takes precedence over `minItems`.
- Arrays that do not have `maxItems` defined will require users to `SIGINT` (`^C`) before the array is ended.
- If `SIGINT` (`^C`) is triggered before `minItems` is met, a validation error will appear. This will require users to `SIGEOF` (`^D`) to end the input.
For more information on things such as `maxItems` and `minItems`, refer to the [revalidator](https://github.com/flatiron/revalidator) repository.
### Alternate Validation API:
Prompt, in addition to iterating over JSON-Schema properties, will also happily iterate over an array of validation objects given an extra 'name' property:
```js
var prompt = require('../lib/prompt');
//
// Start the prompt
//
prompt.start();
//
// Get two properties from the user: username and password
//
prompt.get([{
name: 'username',
required: true
}, {
name: 'password',
hidden: true,
conform: function (value) {
return true;
}
}], function (err, result) {
//
// Log the results.
//
console.log('Command-line input received:');
console.log(' username: ' + result.username);
console.log(' password: ' + result.password);
});
```
### Backward Compatibility
Note that, while this structure is similar to that used by prompt 0.1.x, that the object properties use the same names as in JSON-Schema. prompt 0.2.x is backward compatible with prompt 0.1.x except for asynchronous validation.
### Skipping Prompts
Sometimes power users may wish to skip promts and specify all data as command line options.
if a value is set as a property of `prompt.override` prompt will use that instead of
prompting the user.
``` js
//prompt-override.js
var prompt = require('prompt'),
optimist = require('optimist')
//
// set the overrides
//
prompt.override = optimist.argv
//
// Start the prompt
//
prompt.start();
//
// Get two properties from the user: username and email
//
prompt.get(['username', 'email'], function (err, result) {
//
// Log the results.
//
console.log('Command-line input received:');
console.log(' username: ' + result.username);
console.log(' email: ' + result.email);
})
//: node prompt-override.js --username USER --email EMAIL
```
### Adding Properties to an Object
A common use-case for prompting users for data from the command-line is to extend or create a configuration object that is passed onto the entry-point method for your CLI tool. `prompt` exposes a convenience method for doing just this:
``` js
var obj = {
password: 'lamepassword',
mindset: 'NY'
}
//
// Log the initial object.
//
console.log('Initial object to be extended:');
console.dir(obj);
//
// Add two properties to the empty object: username and email
//
prompt.addProperties(obj, ['username', 'email'], function (err) {
//
// Log the results.
//
console.log('Updated object received:');
console.dir(obj);
});
```
### Prompt history
You can use the `prompt.history()` method to get access to previous prompt input.
``` js
prompt.get([{
name: 'name',
description: 'Your name',
type: 'string',
required: true
}, {
name: 'surname',
description: 'Your surname',
type: 'string',
required: true,
message: 'Please dont use the demo credentials',
conform: function(surname) {
var name = prompt.history('name').value;
return (name !== 'John' || surname !== 'Smith');
}
}], function(err, results) {
console.log(results);
});
```
## Customizing your prompt
Aside from changing `property.message`, you can also change `prompt.message`
and `prompt.delimiter` to change the appearance of your prompt.
The basic structure of a prompt is this:
``` js
prompt.message + prompt.delimiter + property.message + prompt.delimiter;
```
The default `prompt.message` is "prompt," the default `prompt.delimiter` is
": ", and the default `property.message` is `property.name`.
Changing these allows you to customize the appearance of your prompts! In
addition, prompt supports ANSI color codes via the
[colors module](https://github.com/Marak/colors.js) for custom colors. For a
very colorful example:
``` js
var prompt = require("prompt");
//
// Setting these properties customizes the prompt.
//
prompt.message = "Question!".rainbow;
prompt.delimiter = "><".green;
prompt.start();
prompt.get({
properties: {
name: {
description: "What is your name?".magenta
}
}
}, function (err, result) {
console.log("You said your name is: ".cyan + result.name.cyan);
});
```
If you don't want colors, you can set
```js
var prompt = require('prompt');
prompt.colors = false;
```
## Installation
``` bash
$ [sudo] npm install prompt
```
## Running tests
``` bash
$ npm test
```
#### License: MIT
#### Author: [Charlie Robbins](http://github.com/indexzero)
#### Contributors: [Josh Holbrook](http://github.com/jesusabdullah), [Pavan Kumar Sunkara](http://github.com/pksunkara)
[0]: https://github.com/flatiron/prompt/tree/master/examples