TTY::Prompt

A beautiful and powerful interactive command line prompt.

TTY::Prompt provides independent prompt component for TTY toolkit.

Features

Number of prompt types for gathering user input
A robust API for validating complex inputs
User friendly error feedback

Installation

Add this line to your application's Gemfile:

gem 'tty-prompt'

And then execute:

$ bundle

Or install it yourself as:

$ gem install tty-prompt

1. Usage
2. Interface

1. Usage

In order to start asking questions on the command line, create prompt:

prompt = TTY::Prompt.new

and then call ask with the question for simple input:

prompt.ask('What is your name?', default: ENV['USER'])
# => What is your name? (piotr)

To confirm input use yes?:

prompt.yes?('Do you like Ruby?')
# => Do you like Ruby? (Y/n)

If you want to input password or secret information use mask:

prompt.mask("What is your secret?")
# => What is your secret? ••••

Asking question with list of options couldn't be easier using select like so:

prompt.select("Choose your destiny?", %w(Scorpion Kano Jax))
# =>
# Choose your destiny? (Use arrow keys, press Enter to select)
# ‣ Scorpion
#   Kano
#   Jax

Also, asking multiple choice questions is a breeze with multi_select:

choices = %w(vodka beer wine whisky bourbon)
prompt.multi_select("Select drinks?", choices)
# =>
#
# Select drinks? (Use arrow keys, press Space to select and Enter to finish)"
# ‣ ⬡ vodka
#   ⬡ beer
#   ⬡ wine
#   ⬡ whisky
#   ⬡ bourbon

To ask for a selection from enumerated list you can use enum_select:

choices = %w(emacs nano vim)
prompt.enum_select("Select an editor?", choices)
# =>
#
# Select an editor?
#   1) /bin/nano
#   2) /usr/bin/vim.basic
#   3) /usr/bin/vim.tiny
#   Choose 1-3 [2]:

However, if you have a lot of options to choose from you may want to use expand:

choices = [
  { key: 'y', name: 'overwrite this file', value: :yes },
  { key: 'n', name: 'do not overwrite this file', value: :no },
  { key: 'a', name: 'overwrite this file and all later files', value: :all },
  { key: 'd', name: 'show diff', value: :diff },
  { key: 'q', name: 'quit; do not overwrite this file ', value: :quit }
]
prompt.expand('Overwrite Gemfile?', choices)
# =>
# Overwrite Gemfile? (enter "h" for help) [y,n,a,d,q,h]

If you wish to collect more than one answer use collect:

result = prompt.collect do
  key(:name).ask('Name?')

  key(:age).ask('Age?', convert: :int)

  key(:address) do
    key(:street).ask('Street?', required: true)
    key(:city).ask('City?')
    key(:zip).ask('Zip?', validate: /\A\d{3}\Z/)
  end
end
# =>
# {:name => "Piotr", :age => 30, :address => {:street => "Street", :city => "City", :zip => "123"}}

2. Interface

2.1 ask

In order to ask a basic question do:

prompt.ask("What is your name?")

However, to prompt for more complex input you can use robust API by passing hash of properties or using a block like so:

prompt.ask("What is your name?") do |q|
  q.required true
  q.validate /\A\w+\Z/
  q.modify   :capitalize
end

2.2 settings

Below is a list of the settings that may be used for customizing ask, mask, multiline, keypress methods behaviour:

:convert    # conversion applied to input such as :bool or proc
:default    # default value used if none is provided
:echo       # turn echo on and off (default: true)
:in         # specify range '0-9', '0..9', '0...9' or negative '-1..-9'
:modify     # apply answer modification :upcase, :downcase, :trim, :chomp etc..
:required   # If true, value entered must be non-empty (default: false)
:validate   # regex, proc against which input is checked

2.2.1 convert

The convert property is used to convert input to a required type. By default no conversion is performed. The following conversions are provided:

:bool       # true or false for strings such as "Yes", "No"
:date       # date type
:datetime   # datetime type
:file       # File object
:float      # decimal or error if cannot convert
:int        # integer or error if cannot convert
:path       # Pathname object
:range      # range type
:regexp     # regex expression
:string     # string
:symbol     # symbol

For example, if you are interested in range type as answer do the following:

prompt.ask("Provide range of numbers?", convert: :range)
# Provide range of numbers? 1-10
# => 1..10

You can also provide a custom conversion like so:

prompt.ask('Ingredients? (comma sep list)') do |q|
  q.convert -> (input) { input.split(/,\s*/) }
end
# Ingredients? (comma sep list) milk, eggs, flour
# => ['milk', 'eggs', 'flour']

2.2.2 default

The :default option is used if the user presses return key:

prompt.ask('What is your name?', default: 'Anonymous')
# =>
# What is your name? (Anonymous)

2.2.3 echo

To control whether the input is shown back in terminal or not use :echo option like so:

prompt.ask('password:', echo: false)

2.2.4 in

In order to check that provided input falls inside a range of inputs use the in option. For example, if we wanted to ask a user for a single digit in given range we may do following:

ask("Provide number in range: 0-9?") { |q| q.in('0-9') }

2.2.5 modify

Set the :modify option if you want to handle whitespace or letter capitalization.

prompt.ask('Enter text:') do |q|
  q.modify :strip, :collapse
end

Available letter casing settings are:

:up         # change to upper case
:down       # change to small case
:capitalize # capitalize each word

Available whitespace settings are:

:trim     # remove whitespace from both ends of the input
:chomp    # remove whitespace at the end of input
:collapse # reduce all whitespace to single character
:remove   # remove all whitespace

2.2.6 required

To ensure that input is provided use :required option:

prompt.ask("What's your phone number?", required: true)
# What's your phone number?
# >> Value must be provided

2.2.7 validate

In order to validate that input matches a given patter you can pass the validate option. Validate setting accepts Regex, Proc or Symbol.

prompt.ask('What is your username?') do |q|
  q.validate /^[^\.]+\.[^\.]+/
end

The TTY::Prompt comes with bult-in validations for :email and you can use them directly like so:

prompt.ask('What is your email?') { |q| q.validate :email }

2.2.8 messages

By default tty-prompt comes with predefined error messages for required, in, validate options. You can change these and configure to your liking either by inling them with the option:

prompt.ask('What is your email?') do |q|
  question.validate(/\A\w+@\w+\.\w+\Z/, 'Invalid email address')
end

or change the messages key entry out of :required?, :valid?, :range?:

prompt.ask('What is your email?') do |q|
  question.validate(/\A\w+@\w+\.\w+\Z/)
  question.messages[:valid?] = 'Invalid email address'
end

2.2.9 prefix

You can prefix each question asked using the :prefix option. This option can be applied either globally for all prompts or individual for each one:

prompt = TTY::Prompt.new(prefix: '[?] ')

2.2.10 active_color

All prompt types support :active_color option. In case of select, multi_select, enum_select or expand this color is used to highlight the currently selected choice. All the resulted inputs provided by user that are read in by the prompt as answer are highlighted with this color. This option can be applied either globablly for all prompts or individually.

prompt.select('What size?', %w(Large Medium Small), active_color: :cyan)

Please (see pastel)[https://github.com/piotrmurach/pastel#3-supported-colors] for all supported colors.

2.2.11 help_color

Prompts such as select, multi_select, expand support :help_color which is used to customize the help text. This option can be applied either globablly for all prompts or individually.

prompt.select('What size?', %w(Large Medium Small), help_color: :cyan)

2.3 keypress

In order to ask question with a single character or keypress answer use keypress:

prompt.keypress("Which one do you prefer a, b, c or d ?")

2.4 multiline

Asking for multiline input can be done with multiline method.

prompt.multiline("Provide description?")

The reading of input will terminate when empty line is submitted.

2.5 mask

If you require input of confidential information use mask method. By default each character that is printed is replaced by • symbol. All configuration options applicable to ask method can be used with mask as well.

prompt.mask('What is your secret?')
# => What is your secret? ••••

The masking character can be changed by passing :mask option:

prompt.mask('What is your secret?', mask: '\u2665')
# => What is your secret? ♥♥♥♥♥

If you don't wish to show any output use :echo option like so:

prompt.mask('What is your secret?', echo: false)

2.6 yes?/no?

In order to display a query asking for boolean input from user use yes? like so:

prompt.yes?('Do you like Ruby?')
# =>
# Do you like Ruby? (Y/n)

You can further customize question by passing suffix, positive, negative and convert options. The suffix changes text of available options, the positive specifies display string for successful answer and negative changes display string for negative answer. The final value is a boolean provided the convert option evaluates to boolean.

It's enough to provide the suffix option for the prompt to accept matching answers with correct labels:

prompt.yes?("Are you a human?") do |q|
  q.suffix 'Yup/nope'
end
# =>
# Are you a human? (Yup/nope)

Alternatively, instead of suffix option provide the positive and negative labels:

prompt.yes?("Are you a human?") do |q|
  q.default false
  q.positive 'Yup'
  q.negative 'Nope'
end
# =>
# Are you a human? (yup/Nope)

Finally, providing all available options you can ask fully customized question:

prompt.yes?('Are you a human?') do |q|
  q.suffix 'Agree/Disagree'
  q.positive 'Agree'
  q.negative 'Disagree'
  q.convert -> (input) { !input.match(/^agree$/i).nil? }
end
# =>
# Are you a human? (Agree/Disagree)

There is also the opposite for asking confirmation of negative question:

prompt.no?('Do you hate Ruby?')
# =>
# Do you hate Ruby? (y/N)

Similarly to yes? method, you can supply the same options to customize the question.

2.7 select

For asking questions involving list of options use select method by passing the question and possible choices:

prompt.select("Choose your destiny?", %w(Scorpion Kano Jax))
# =>
# Choose your destiny? (Use arrow keys, press Enter to select)
# ‣ Scorpion
#   Kano
#   Jax

You can also provide options through DSL using the choice method for single entry and/or choices for more than one choice:

prompt.select("Choose your destiny?") do |menu|
  menu.choice 'Scorpion'
  menu.choice 'Kano'
  menu.choice 'Jax'
end
# =>
# Choose your destiny? (Use arrow keys, press Enter to select)
# ‣ Scorpion
#   Kano
#   Jax

By default the choice name is used as return value, but you can provide your custom values including a Proc object:

prompt.select("Choose your destiny?") do |menu|
  menu.choice 'Scorpion', 1
  menu.choice 'Kano', 2
  menu.choice 'Jax', -> { 'Nice choice captain!' }
end
# =>
# Choose your destiny? (Use arrow keys, press Enter to select)
# ‣ Scorpion
#   Kano
#   Jax

If you wish you can also provide a simple hash to denote choice name and its value like so:

choices = {'Scorpion' => 1, 'Kano' => 2, 'Jax' => 3}
prompt.select("Choose your destiny?", choices)

To mark particular answer as selected use default with index of the option starting from 1:

prompt.select("Choose your destiny?") do |menu|
  menu.default 3

  menu.choice 'Scorpion', 1
  menu.choice 'Kano', 2
  menu.choice 'Jax', 3
end
# =>
# Choose your destiny? (Use arrow keys, press Enter to select)
#   Scorpion
#   Kano
# ‣ Jax

For ordered choices set enum to any delimiter String. In that way, you can use arrows keys and numbers (0-9) to select the item.

prompt.select("Choose your destiny?") do |menu|
  menu.enum '.'

  menu.choice 'Scorpion', 1
  menu.choice 'Kano', 2
  menu.choice 'Jax', 3
end
# =>
# Choose your destiny? (Use arrow or number (0-9) keys, press Enter to select)
#   1. Scorpion
#   2. Kano
# ‣ 3. Jax

You can configure help message and/or marker like so

choices = %w(Scorpion Kano Jax)
prompt.select("Choose your destiny?", choices, help: "(Bash keyboard)", marker: '>')
# =>
# Choose your destiny? (Bash keyboard)
# > Scorpion
#   Kano
#   Jax

2.8 multi_select

For asking questions involving multiple selection list use multi_select method by passing the question and possible choices:

choices = %w(vodka beer wine whisky bourbon)
prompt.select("Select drinks?", choices)
# =>
#
# Select drinks? (Use arrow keys, press Space to select and Enter to finish)"
# ‣ ⬡ vodka
#   ⬡ beer
#   ⬡ wine
#   ⬡ whisky
#   ⬡ bourbon

As a return value, the multi_select will always return an array by default populated with the names of the choices. If you wish to return custom values for the available choices do:

choices = {vodka: 1, beer: 2, wine: 3, whisky: 4, bourbon: 5}
prompt.select("Select drinks?", choices)

# Provided that vodka and beer have been selected, the function will return
# => [1, 2]

Similar to select method, you can also provide options through DSL using the choice method for single entry and/or choices call for more than one choice:

prompt.multi_select("Select drinks?") do |menu|
  menu.choice :vodka, {score: 1}
  menu.choice :beer, 2
  menu.choice :wine, 3
  menu.choices whisky: 4, bourbon: 5
end

To mark choice(s) as selected use the default option with index(s) of the option(s) starting from 1:

prompt.multi_select("Select drinks?") do |menu|
  menu.default 2, 5

  menu.choice :vodka,   {score: 10}
  menu.choice :beer,    {score: 20}
  menu.choice :wine,    {score: 30}
  menu.choice :whisky,  {score: 40}
  menu.choice :bourbon, {score: 50}
end
# =>
# Select drinks? beer, bourbon
#   ⬡ vodka
#   ⬢ beer
#   ⬡ wine
#   ⬡ whisky
# ‣ ⬢ bourbon

Like select, for ordered choices set enum to any delimiter String. In that way, you can use arrows keys and numbers (0-9) to select the item.

prompt.multi_select("Select drinks?") do |menu|
  menu.enum ')'

  menu.choice :vodka,   {score: 10}
  menu.choice :beer,    {score: 20}
  menu.choice :wine,    {score: 30}
  menu.choice :whisky,  {score: 40}
  menu.choice :bourbon, {score: 50}
end
# =>
# Select drinks? beer, bourbon
#   ⬡ 1) vodka
#   ⬢ 2) beer
#   ⬡ 3) wine
#   ⬡ 4) whisky
# ‣ ⬢ 5) bourbon

And when you press enter you will see the following selected:

# Select drinks? beer, bourbon
# => [{score: 20}, {score: 50}]

You can configure help message and/or marker like so

choices = {vodka: 1, beer: 2, wine: 3, whisky: 4, bourbon: 5}
prompt.select("Select drinks?", choices, help: 'Press beer can against keyboard')
# =>
# Select drinks? (Press beer can against keyboard)"
# ‣ ⬡ vodka
#   ⬡ beer
#   ⬡ wine
#   ⬡ whisky
#   ⬡ bourbon

2.9 enum_select

In order to ask for standard selection from indexed list you can use enum_select and pass question together with possible choices:

choices = %w(emacs nano vim)
prompt.enum_select("Select an editor?")
# =>
#
# Select an editor?
#   1) nano
#   2) vim
#   3) emacs
#   Choose 1-3 [1]:

Similar to select and multi_select, you can provide question options through DSL using choice method and/or choices like so:

choices = %w(nano vim emacs)
prompt.enum_select("Select an editor?") do |menu|
  menu.choice :nano,  '/bin/nano'
  menu.choice :vim,   '/usr/bin/vim'
  menu.choice :emacs, '/usr/bin/emacs'
end
# =>
#
# Select an editor?
#   1) nano
#   2) vim
#   3) emacs
#   Choose 1-3 [1]:
#
# Select an editor? /bin/nano

You can change the indexed numbers by passing enum option and the default option by using default like so

choices = %w(nano vim emacs)
prompt.enum_select("Select an editor?") do |menu|
  menu.default 2
  menu.enum '.'

  menu.choice :nano,  '/bin/nano'
  menu.choice :vim,   '/usr/bin/vim'
  menu.choice :emacs, '/usr/bin/emacs'
end
# =>
#
# Select an editor?
#   1. nano
#   2. vim
#   3. emacs
#   Choose 1-3 [2]:
#
# Select an editor? /usr/bin/vim

2.10 expand

The expand provides a compact way to ask a question with many options.

As first argument expand takes the message to display and as a second an array of choices. Compared to the select, multi_select and enum_select, the choices need to be objects that include :key, :name and :value keys. The :key must be a single character. The help choice is added automatically as the last option and the key h.

choices = [
  {
    key: 'y',
    name: 'overwrite this file',
    value: :yes
  }, {
    key: 'n',
    name: 'do not overwrite this file',
    value: :no
  }, {
    key: 'q',
    name: 'quit; do not overwrite this file ',
    value: :quit
  }
]

The choices can also be provided through DSL using the choice method. The :value can be a primitive value or Proc instance that gets executed and whose value is used as returned type. For example:

prompt.expand('Overwrite Gemfile?') do |q|
  q.choice key: 'y', name: 'Overwrite'      do :ok end
  q.choice key: 'n', name: 'Skip',          value: :no
  q.choice key: 'a', name: 'Overwrite all', value: :all
  q.choice key: 'd', name: 'Show diff',     value: :diff
  q.choice key: 'q', name: 'Quit',          value: :quit
end

The first element in the array of choices or provided via choice DSL will be the default choice, you can change that by passing default option.

prompt.expand('Overwrite Gemfile?', choices)
# =>
# Overwrite Gemfile? (enter "h" for help) [y,n,q,h]

Each time user types an option a hint will be displayed:

# Overwrite Gemfile? (enter "h" for help) [y,n,a,d,q,h] y
# >> overwrite this file

If user types h and presses enter, an expanded view will be shown which further allows to refine the choice:

# Overwrite Gemfile?
#   y - overwrite this file
#   n - do not overwrite this file
#   q - quit; do not overwrite this file
#   h - print help
#   Choice [y]:

Run examples/expand.rb to see the prompt in action.

2.11 collect

In order to collect more than one answer use collect method. Using the key you can describe the answers key name. All the methods for asking user input such as ask, mask, select can be directly invoked on the key. The key composition is very flexible by allowing nested keys. If you want the value to be automatically converted to required type use convert.

For example to gather some contact information do:

prompt.collect do
  key(:name).ask('Name?')

  key(:age).ask('Age?', convert: :int)

  key(:address) do
    key(:street).ask('Street?', required: true)
    key(:city).ask('City?')
    key(:zip).ask('Zip?', validate: /\A\d{3}\Z/)
  end
end
# =>
# {:name => "Piotr", :age => 30, :address => {:street => "Street", :city => "City", :zip => "123"}}

2.12 suggest

To suggest possible matches for the user input use suggest method like so:

prompt.suggest('sta', ['stage', 'stash', 'commit', 'branch'])
# =>
# Did you mean one of these?
#         stage
#         stash

To customize query text presented pass :single_text and :plural_text options to respectively change the message when one match is found or many.

possible = %w(status stage stash commit branch blame)
prompt.suggest('b', possible, indent: 4, single_text: 'Perhaps you meant?')
# =>
# Perhaps you meant?
#     blame

2.13 slider

If you have constrained range of numbers for user to choose from you may consider using slider. The slider provides easy visual way of picking a value marked by O marker.

prompt.slider('What size?', min: 32, max: 54, step: 2)
# =>
#
# What size? (User arrow keys, press Enter to select)
# |------O-----| 44

Slider can be configured through DSL as well:

prompt.slider('What size?') do |range|
  range.default 4
  range.min 0
  range.max 20
  range.step 2
end
# =>
#
# What size? (User arrow keys, press Enter to select)
# |--O-------| 4

2.14 say

To simply print message out to stdout use say like so:

prompt.say(...)

The say method also accepts option :color which supports all the colors provided by pastel

TTY::Prompt provides more specific versions of say method to better express intenation behind the message such as ok, warn and error.

2.15 ok

Print message(s) in green do:

prompt.ok(...)

2.16 warn

Print message(s) in yellow do:

prompt.warn(...)

2.17 error

Print message(s) in red do:

prompt.error(...)

Contributing

Fork it ( https://github.com/piotrmurach/tty-prompt/fork )
Create your feature branch (git checkout -b my-new-feature)
Commit your changes (git commit -am 'Add some feature')
Push to the branch (git push origin my-new-feature)
Create a new Pull Request

This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

CelineColas/play_with_prompt