readline-ui

readline-ui

Create a readline interface with default settings to use in prompts.

Install

Install with npm:

$ npm install --save readline-ui

Usage

var UI = require('readline-ui');
var ui = new UI();

Example

The following example shows how to create a basic input prompt. This example is a greatly simplified version of prompt-base.

(This code is also in example.js if you want to run it yourself.)

var cyan = require('ansi-cyan');
var UI = require('readline-ui');
var ui = new UI();

// first, we need to render the "question" 
// to display in the terminal
var prompt = '? foo ';
ui.render(prompt);

// on keypress events, re-render the prompt 
// along with user input
ui.on('keypress', function() {
  ui.render(prompt + ui.rl.line);
});

// when the "line" event is emitted (from the "enter" keypress)
// we `.end()` to unmute the output stream then pause the readline. 
ui.on('line', function(answer) {
  ui.render(prompt + cyan(answer));
  ui.end();
  ui.rl.pause();
  console.log({color: answer});
});

API

.onKeypress

Handle keypress events.

Params

• str {String}
• key {Object}
• returns {undefined}

.render

Render the prompt with the given input and optional footer.

Params

• input {String}
• footer {String}: (optional)
• returns {undefined}

.clearLines

Remove n lines from the bottom of the terminal

Params

• lines {Number}: Number of lines to remove

.cacheCursorPos

Cache the current cursor's column and line position.

• returns {Object}: UI instance.

.restoreCursorPos

Restore the cursor position to the cached column and line.

• returns {Object}: UI instance.

.resume

Resume the input stream.

.pause

Pause the input stream, allowing it to be resumed later if necessary.

.close

Close the readline.Interface instance and relinquish control over the input and output streams. Also removes event listeners, and restores/unmutes prompt functionality.

.forceClose

Close the interface when the keypress is ^C

.finish

Returns an "indentity" function that calls .close(), which can be used as the final .then() function with promises.

.end

Default method for writing a prompt to the terminal. This can be overridden.

.mute

Mutes the output stream that was used to create the readline interface, and returns a function for unmuting the stream. This is useful in unit tests.

• returns {Function}

Example

// mute the stream
var unmute = ui.mute();

// unmute the stream
unmute();

.log

Unmute then write to the output stream that was used to create the readline interface, then re-mute the stream. Useful for debugging prompts.

Attribution

Inspired by the "screen manager" code in Inquirer.

About

Related projects

• enquirer: Intuitive, plugin-based prompt system for node.js. | homepage
• prompt-choices: Create an array of multiple choice objects for use in prompts. | homepage
• prompt-question: Question object, used by Enquirer and prompt plugins. | homepage
• readline-utils: Readline utils, for moving the cursor, clearing lines, creating a readline interface, and more. | homepage

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

Please read the contributing guide for advice on opening issues, pull requests, and coding standards.

Building docs

(This project's readme.md is generated by verb, please don't edit the readme directly. Any changes to the readme must be made in the .verb.md readme template.)

To generate the readme, run the following command:

$ npm install -g verbose/verb#dev verb-generate-readme && verb

Running tests

Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:

$ npm install && npm test

Author

Jon Schlinkert

• github/jonschlinkert
• twitter/jonschlinkert

License

Copyright © 2017, Jon Schlinkert. Released under the MIT License.

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This file was generated by verb-generate-readme, v0.6.0, on June 04, 2017.