class/class_backend/node_modules/prompts

❯ Prompts

Lightweight, beautiful and user-friendly interactive prompts
_{>_ Easy to use CLI prompts to enquire users for information▌}

• Simple: prompts has no big dependencies nor is it broken into a dozen tiny modules that only work well together.
• User friendly: prompt uses layout and colors to create beautiful cli interfaces.
• Promised: uses promises and async/await. No callback hell.
• Flexible: all prompts are independent and can be used on their own.
• Testable: provides a way to submit answers programmatically.
• Unified: consistent experience across all prompts.

❯ Install

$ npm install --save prompts

This package supports Node 6 and above

❯ Usage

const prompts = require('prompts');

(async () => {
  const response = await prompts({
    type: 'number',
    name: 'value',
    message: 'How old are you?',
    validate: value => value < 18 ? `Nightclub is 18+ only` : true
  });

  console.log(response); // => { value: 24 }
})();

See example.js for more options.

❯ Examples

Single Prompt

Prompt with a single prompt object. Returns an object with the response.

const prompts = require('prompts');

(async () => {
  const response = await prompts({
    type: 'text',
    name: 'meaning',
    message: 'What is the meaning of life?'
  });

  console.log(response.meaning);
})();

Prompt Chain

Prompt with a list of prompt objects. Returns an object with the responses. Make sure to give each prompt a unique name property to prevent overwriting values.

const prompts = require('prompts');

const questions = [
  {
    type: 'text',
    name: 'username',
    message: 'What is your GitHub username?'
  },
  {
    type: 'number',
    name: 'age',
    message: 'How old are you?'
  },
  {
    type: 'text',
    name: 'about',
    message: 'Tell something about yourself',
    initial: 'Why should I?'
  }
];

(async () => {
  const response = await prompts(questions);

  // => response => { username, age, about }
})();

Dynamic Prompts

Prompt properties can be functions too. Prompt Objects with type set to falsy values are skipped.

const prompts = require('prompts');

const questions = [
  {
    type: 'text',
    name: 'dish',
    message: 'Do you like pizza?'
  },
  {
    type: prev => prev == 'pizza' ? 'text' : null,
    name: 'topping',
    message: 'Name a topping'
  }
];

(async () => {
  const response = await prompts(questions);
})();

❯ API

prompts(prompts, options)

Type: Function
Returns: Object

Prompter function which takes your prompt objects and returns an object with responses.

prompts

Type: Array|Object

Array of prompt objects. These are the questions the user will be prompted. You can see the list of supported prompt types here.

Prompts can be submitted (return, enter) or canceled (esc, abort, ctrl+c, ctrl+d). No property is being defined on the returned response object when a prompt is canceled.

options.onSubmit

Type: Function
Default: () => {}

Callback that's invoked after each prompt submission. Its signature is (prompt, answer, answers) where prompt is the current prompt object, answer the user answer to the current question and answers the user answers so far. Async functions are supported.

Return true to quit the prompt chain and return all collected responses so far, otherwise continue to iterate prompt objects.

Example:

(async () => {
  const questions = [{ ... }];
  const onSubmit = (prompt, answer) => console.log(`Thanks I got ${answer} from ${prompt.name}`);
  const response = await prompts(questions, { onSubmit });
})();

options.onCancel

Type: Function
Default: () => {}

Callback that's invoked when the user cancels/exits the prompt. Its signature is (prompt, answers) where prompt is the current prompt object and answers the user answers so far. Async functions are supported.

Return true to continue and prevent the prompt loop from aborting. On cancel responses collected so far are returned.

Example:

(async () => {
  const questions = [{ ... }];
  const onCancel = prompt => {
    console.log('Never stop prompting!');
    return true;
  }
  const response = await prompts(questions, { onCancel });
})();

override

Type: Function

Preanswer questions by passing an object with answers to prompts.override. Powerful when combined with arguments of process.

Example

const prompts = require('prompts');
prompts.override(require('yargs').argv);

(async () => {
  const response = await prompts([
    {
      type: 'text',
      name: 'twitter',
      message: `What's your twitter handle?`
    },
    {
      type: 'multiselect',
      name: 'color',
      message: 'Pick colors',
      choices: [
        { title: 'Red', value: '#ff0000' },
        { title: 'Green', value: '#00ff00' },
        { title: 'Blue', value: '#0000ff' }
      ],
    }
  ]);

  console.log(response);
})();

inject(values)

Type: Function

Programmatically inject responses. This enables you to prepare the responses ahead of time. If any injected value is found the prompt is immediately resolved with the injected value. This feature is intended for testing only.

values

Type: Array

Array with values to inject. Resolved values are removed from the internal inject array. Each value can be an array of values in order to provide answers for a question asked multiple times. If a value is an instance of Error it will simulate the user cancelling/exiting the prompt.

Example:

const prompts = require('prompts');

prompts.inject([ '@terkelg', ['#ff0000', '#0000ff'] ]);

(async () => {
  const response = await prompts([
    {
      type: 'text',
      name: 'twitter',
      message: `What's your twitter handle?`
    },
    {
      type: 'multiselect',
      name: 'color',
      message: 'Pick colors',
      choices: [
        { title: 'Red', value: '#ff0000' },
        { title: 'Green', value: '#00ff00' },
        { title: 'Blue', value: '#0000ff' }
      ],
    }
  ]);

  // => { twitter: 'terkelg', color: [ '#ff0000', '#0000ff' ] }
})();

❯ Prompt Objects

Prompts Objects are JavaScript objects that define the "questions" and the type of prompt. Almost all prompt objects have the following properties:

{
  type: String | Function,
  name: String | Function,
  message: String | Function,
  initial: String | Function | Async Function
  format: Function | Async Function,
  onRender: Function
  onState: Function
  stdin: Readable
  stdout: Writeable
}

Each property be of type function and will be invoked right before prompting the user.

The function signature is (prev, values, prompt), where prev is the value from the previous prompt, values is the response object with all values collected so far and prompt is the previous prompt object.

Function example:

{
  type: prev => prev > 3 ? 'confirm' : null,
  name: 'confirm',
  message: (prev, values) => `Please confirm that you eat ${values.dish} times ${prev} a day?`
}

The above prompt will be skipped if the value of the previous prompt is less than 3.

type

Type: String|Function

Defines the type of prompt to display. See the list of prompt types for valid values.

If type is a falsy value the prompter will skip that question.

{
  type: null,
  name: 'forgetme',
  message: `I'll never be shown anyway`,
}

name

Type: String|Function

The response will be saved under this key/property in the returned response object. In case you have multiple prompts with the same name only the latest response will be stored.

Make sure to give prompts unique names if you don't want to overwrite previous values.

message

Type: String|Function

The message to be displayed to the user.

initial

Type: String|Function

Optional default prompt value. Async functions are supported too.

format

Type: Function

Receive the user input and return the formatted value to be used inside the program. The value returned will be added to the response object.

The function signature is (val, values), where val is the value from the current prompt and values is the current response object in case you need to format based on previous responses.

Example:

{
  type: 'number',
  name: 'price',
  message: 'Enter price',
  format: val => Intl.NumberFormat(undefined, { style: 'currency', currency: 'USD' }).format(val);
}

onRender

Type: Function

Callback for when the prompt is rendered. The function receives kleur as its first argument and this refers to the current prompt.

Example:

{
  type: 'number',
  message: 'This message will be overridden',
  onRender(kleur) {
    this.msg = kleur.cyan('Enter a number');
  }
}

onState

Type: Function

Callback for when the state of the current prompt changes. The function signature is (state) where state is an object with a snapshot of the current state. The state object has two properties value and aborted. E.g { value: 'This is ', aborted: false }

stdin and stdout

Type: Stream

By default, prompts uses process.stdin for receiving input and process.stdout for writing output. If you need to use different streams, for instance process.stderr, you can set these with the stdin and stdout properties.

❯ Types

• text
• password
• invisible
• number
• confirm
• list
• toggle
• select
• multiselect
• autocompleteMultiselect
• autocomplete
• date

---

text(message, [initial], [style])

Text prompt for free text input.

Hit tab to autocomplete to initial value when provided.

Example

{
  type: 'text',
  name: 'value',
  message: `What's your twitter handle?`
}

Options

Param	Type	Description
message	string	Prompt message to display
initial	string	Default string value
style	string	Render style (default, password, invisible, emoji). Defaults to default
format	function	Receive user input. The returned value will be added to the response object
validate	function	Receive user input. Should return true if the value is valid, and an error message String otherwise. If false is returned, a default error message is shown
onRender	function	On render callback. Keyword this refers to the current prompt
onState	function	On state change callback. Function signature is an object with two properties: value and aborted

↑ back to: Prompt types

---

password(message, [initial])

Password prompt with masked input.

This prompt is a similar to a prompt of type 'text' with style set to 'password'.

Example

{
  type: 'password',
  name: 'value',
  message: 'Tell me a secret'
}

Options

Param	Type	Description
message	string	Prompt message to display
initial	string	Default string value
format	function	Receive user input. The returned value will be added to the response object
validate	function	Receive user input. Should return true if the value is valid, and an error message String otherwise. If false is returned, a default error message is shown
onRender	function	On render callback. Keyword this refers to the current prompt
onState	function	On state change callback. Function signature is an object with two properties: value and aborted

↑ back to: Prompt types

---

invisible(message, [initial])

Prompts user for invisible text input.

This prompt is working like sudo where the input is invisible. This prompt is a similar to a prompt of type 'text' with style set to 'invisible'.

Example

{
  type: 'invisible',
  name: 'value',
  message: 'Enter password'
}

Options

Param	Type	Description
message	string	Prompt message to display
initial	string	Default string value
format	function	Receive user input. The returned value will be added to the response object
validate	function	Receive user input. Should return true if the value is valid, and an error message String otherwise. If false is returned, a default error message is shown
onRender	function	On render callback. Keyword this refers to the current prompt
onState	function	On state change callback. Function signature is an object with two properties: value and aborted

↑ back to: Prompt types

---

number(message, initial, [max], [min], [style])

Prompts user for number input.

You can type in numbers and use up/down to increase/decrease the value. Only numbers are allowed as input. Hit tab to autocomplete to initial value when provided.

Example

{
  type: 'number',
  name: 'value',
  message: 'How old are you?',
  initial: 0,
  style: 'default',
  min: 2,
  max: 10
}

Options

Param	Type	Description
message	string	Prompt message to display
initial	number	Default number value
format	function	Receive user input. The returned value will be added to the response object
validate	function	Receive user input. Should return true if the value is valid, and an error message String otherwise. If false is returned, a default error message is shown
max	number	Max value. Defaults to Infinity
min	number	Min value. Defaults to -infinity
float	boolean	Allow floating point inputs. Defaults to false
round	number	Round float values to x decimals. Defaults to 2
increment	number	Increment step when using arrow keys. Defaults to 1
style	string	Render style (default, password, invisible, emoji). Defaults to default
onRender	function	On render callback. Keyword this refers to the current prompt
onState	function	On state change callback. Function signature is an object with two properties: value and aborted

↑ back to: Prompt types

---

confirm(message, [initial])

Classic yes/no prompt.

Hit y or n to confirm/reject.

Example

{
  type: 'confirm',
  name: 'value',
  message: 'Can you confirm?',
  initial: true
}

Options

Param	Type	Description
message	string	Prompt message to display
initial	boolean	Default value. Default is false
format	function	Receive user input. The returned value will be added to the response object
onRender	function	On render callback. Keyword this refers to the current prompt
onState	function	On state change callback. Function signature is an object with two properties: value and aborted

↑ back to: Prompt types

---

list(message, [initial])

List prompt that return an array.

Similar to the text prompt, but the output is an Array containing the string separated by separator.

{
  type: 'list',
  name: 'value',
  message: 'Enter keywords',
  initial: '',
  separator: ','
}

Param	Type	Description
message	string	Prompt message to display
initial	boolean	Default value
format	function	Receive user input. The returned value will be added to the response object
separator	string	String separator. Will trim all white-spaces from start and end of string. Defaults to ','
onRender	function	On render callback. Keyword this refers to the current prompt
onState	function	On state change callback. Function signature is an object with two properties: value and aborted

↑ back to: Prompt types

---

toggle(message, [initial], [active], [inactive])

Interactive toggle/switch prompt.

Use tab or arrow keys/tab/space to switch between options.

Example

{
  type: 'toggle',
  name: 'value',
  message: 'Can you confirm?',
  initial: true,
  active: 'yes',
  inactive: 'no'
}

Options

Param	Type	Description
message	string	Prompt message to display
initial	boolean	Default value. Defaults to false
format	function	Receive user input. The returned value will be added to the response object
active	string	Text for active state. Defaults to 'on'
inactive	string	Text for inactive state. Defaults to 'off'
onRender	function	On render callback. Keyword this refers to the current prompt
onState	function	On state change callback. Function signature is an object with two properties: value and aborted

↑ back to: Prompt types

---

select(message, choices, [initial], [hint], [warn])

Interactive select prompt.

Use up/down to navigate. Use tab to cycle the list.

Example

{
  type: 'select',
  name: 'value',
  message: 'Pick a color',
  choices: [
    { title: 'Red', description: 'This option has a description', value: '#ff0000' },
    { title: 'Green', value: '#00ff00', disabled: true },
    { title: 'Blue', value: '#0000ff' }
  ],
  initial: 1
}

Options

Param	Type	Description
message	string	Prompt message to display
initial	number	Index of default value
format	function	Receive user input. The returned value will be added to the response object
hint	string	Hint to display to the user
warn	string	Message to display when selecting a disabled option
choices	Array	Array of strings or choices objects [{ title, description, value, disabled }, ...]. The choice's index in the array will be used as its value if it is not specified.
onRender	function	On render callback. Keyword this refers to the current prompt
onState	function	On state change callback. Function signature is an object with two properties: value and aborted

↑ back to: Prompt types

---

multiselect(message, choices, [initial], [max], [hint], [warn])

autocompleteMultiselect(same)

Interactive multi-select prompt.
Autocomplete is a searchable multiselect prompt with the same options. Useful for long lists.

Use space to toggle select/unselect and up/down to navigate. Use tab to cycle the list. You can also use right to select and left to deselect. By default this prompt returns an array containing the values of the selected items - not their display title.

Example

{
  type: 'multiselect',
  name: 'value',
  message: 'Pick colors',
  choices: [
    { title: 'Red', value: '#ff0000' },
    { title: 'Green', value: '#00ff00', disabled: true },
    { title: 'Blue', value: '#0000ff', selected: true }
  ],
  max: 2,
  hint: '- Space to select. Return to submit'
}

Options

Param	Type	Description
message	string	Prompt message to display
format	function	Receive user input. The returned value will be added to the response object
instructions	string or boolean	Prompt instructions to display
choices	Array	Array of strings or choices objects [{ title, value, disabled }, ...]. The choice's index in the array will be used as its value if it is not specified.
optionsPerPage	number	Number of options displayed per page (default: 10)
min	number	Min select - will display error
max	number	Max select
hint	string	Hint to display to the user
warn	string	Message to display when selecting a disabled option
onRender	function	On render callback. Keyword this refers to the current prompt
onState	function	On state change callback. Function signature is an object with two properties: value and aborted

This is one of the few prompts that don't take a initial value. If you want to predefine selected values, give the choice object an selected property of true.

↑ back to: Prompt types

---

autocomplete(message, choices, [initial], [suggest], [limit], [style])

Interactive auto complete prompt.

The prompt will list options based on user input. Type to filter the list. Use ⇧/⇩ to navigate. Use tab to cycle the result. Use Page Up/Page Down (on Mac: fn + ⇧ / ⇩) to change page. Hit enter to select the highlighted item below the prompt.

The default suggests function is sorting based on the title property of the choices. You can overwrite how choices are being filtered by passing your own suggest function.

Example

{
  type: 'autocomplete',
  name: 'value',
  message: 'Pick your favorite actor',
  choices: [
    { title: 'Cage' },
    { title: 'Clooney', value: 'silver-fox' },
    { title: 'Gyllenhaal' },
    { title: 'Gibson' },
    { title: 'Grant' }
  ]
}

Options

Param	Type	Description
message	string	Prompt message to display
format	function	Receive user input. The returned value will be added to the response object
choices	Array	Array of auto-complete choices objects [{ title, value }, ...]
suggest	function	Filter function. Defaults to sort by title property. suggest should always return a promise. Filters using title by default
limit	number	Max number of results to show. Defaults to 10
style	string	Render style (default, password, invisible, emoji). Defaults to 'default'
initial	string | number	Default initial value
clearFirst	boolean	The first ESCAPE keypress will clear the input
fallback	string	Fallback message when no match is found. Defaults to initial value if provided
onRender	function	On render callback. Keyword this refers to the current prompt
onState	function	On state change callback. Function signature is an object with three properties: value, aborted and exited

Example on what a suggest function might look like:

const suggestByTitle = (input, choices) =>
    Promise.resolve(choices.filter(i => i.title.slice(0, input.length) === input))

↑ back to: Prompt types

---

date(message, [initial], [warn])

Interactive date prompt.

Use left/right/tab to navigate. Use up/down to change date.

Example

{
  type: 'date',
  name: 'value',
  message: 'Pick a date',
  initial: new Date(1997, 09, 12),
  validate: date => date > Date.now() ? 'Not in the future' : true
}

Options

Param	Type	Description
message	string	Prompt message to display
initial	date	Default date
locales	object	Use to define custom locales. See below for an example.
mask	string	The format mask of the date. See below for more information. Default: YYYY-MM-DD HH:mm:ss
validate	function	Receive user input. Should return true if the value is valid, and an error message String otherwise. If false is returned, a default error message is shown
onRender	function	On render callback. Keyword this refers to the current prompt
onState	function	On state change callback. Function signature is an object with two properties: value and aborted

Default locales:

{
  months: [
    'January', 'February', 'March', 'April',
    'May', 'June', 'July', 'August',
    'September', 'October', 'November', 'December'
  ],
  monthsShort: [
    'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
    'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'
  ],
  weekdays: [
    'Sunday', 'Monday', 'Tuesday', 'Wednesday',
    'Thursday', 'Friday', 'Saturday'
  ],
  weekdaysShort: [
    'Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'
  ]
}

Formatting: See full list of formatting options in the wiki

↑ back to: Prompt types

---

❯ Credit

Many of the prompts are based on the work of derhuerst.

❯ License

MIT © Terkel Gjervig