generate-component v0.3.0

Posted on April 16, 2017
Tags: haskell, react, react native



Over the weekend I released version 0.3.0 of the React component generator I wrote about a few months ago.

New features (subcommands, a config file, new component type generators, and propType insertion) are detailed below.

The release can be found at the repo.

generate-component v0.3.0

The updates in this version of the component generator came about after five months of use while working on a React Native project. During that time, I learned more about both what I want out of a component generator, and what generate-component lacked. The new config file provides quality of life improvements by reducing the need to supply common commands when generating new components. Other changes, including generators for different component types and propType arugments, make generate-component generally more useful.

Config file

Perhaps the biggest change is that generate-component now uses a YAML configuration file. The motivation behind the config file is in setting project defaults for project type, component directory, and component type.

An example config file1:

# Type of the current project; determines what files will be
# generated for a component.
# Valid values: React | ReactNative
projectType: ReactNative

# Default directory in which to generate components.
defaultDirectory: app/components

# Style of components to generate
# Valid values: CreateClass | ES6Class | Functional
componentType: ES6Class

Project Type

In previous versions, project type defaulted to React while a command line flag (-n) indicated a React Native project. For React Native projects, this meant that the flag had to be provided every time a component was generated. Now, the project type specified in the config file is the default.

Valid project types are React | ReactNative

Default Directory

The default directory in which new components are generated is also specifiable in the config file. There is a command line option (-d) that overrides the default if provided.

Previously, the component was generated in relative to the current directory; now components are generated relative to the project root (determined by the presence of a node_modules directory).

Component Types

The final config file option is the default component type. In previous versions, the only type of component that generate-component made was a functional component. Now, it is able to generate ES6 class style components, functional components, and (the deprecated) React.createClass components2. The default type of component can be specified in the config file, but can be overridden by a command line argument (-t).

Valid component types are: ES6Class | Functional | CreateClass


generate-component now has two subcommands: init and gen.

$ generate-component --help
Flexible generator for React/React-Native components. Generate ES6 class,
React.createClass, and functional components with optional proptypes and redux

Usage: generate-component COMMAND
Generate React/React-Native components

Available options:
-h,--help                Show this help text

Available commands:
init                     Create a config file
gen                      Generate a component

generate-component init is used to initialize generate component with a new config file. This should be run in the project’s root directory.

generate-component gen is the command to actually generate a new component.

Options for generate-component gen

There are five optional arguments when generating a component3:

-d --directory ARG
where to generate the component; relative to the project root.
-r --redux-container
Generate a Redux connected container along with the component.
-n --react-native
A flag that indicates a React Native project; defaults to React.
-t --component-type ARG
Component type: ES6Class | Functional | CreateClass
-p --proptypes ARG
name:type pairs of PropTypes for the component.


Props and PropTypes for the component can now be specified from the command line. They are currently parsed as colon separated, name:propType pairs. Currently there is no validation check for PropTypes in the provided input. To provide multiple props, the argument needs to be quoted.


Using the config file from above:

$ generate-component gen Post -p "author:string title:string body:string"
Making directory at: /tmp/app/components/Post
Copying files...
Writing /tmp/app/components/Post/index.js...Done!
Writing /tmp/app/components/Post/Post.js...Done!
Writing /tmp/app/components/Post/styles.js...Done!


// @flow
  NOTE: This file was auto-generated for a component
  named "Post"; it is intended to be modified as
  needed to be useful.

import React from 'react';
import PropTypes from 'prop-types';
import {View} from 'react-native';

import styles from './styles';

class Post extends Component {
  static propTypes = {
    author: PropTypes.string,
    title: PropTypes.string,
    body: PropTypes.string

  render() {
    return (

export default Post;

For functional components, the prop names get destructured as the argument to the function:

$ generate-component gen Comment -p "author:string comment:string id:number" -t Functional


// @flow
  NOTE: This file was auto-generated for a component
  named "Comment"; it is intended to be modified as
  needed to be useful.

import React from 'react';
import PropTypes from 'prop-types';
import {View} from 'react-native';

import styles from './styles';

const Comment = ({author, comment, id}) => (

Comment.propTypes = {
  author: PropTypes.string,
  comment: PropTypes.string,
  id: PropTypes.number

export default Comment;


These updates to generate-component were added to make it both easier to use (config file) and more powerful (PropTypes, generators for multiple component types). I don’t foresee major changes to the API at this point, just refinements to the internals. Given that no huge issues arise rollowing a short test period, this version will likely be promoted to v1.0.


  1. Generated with generate-component init; modified from the default to change projectType to ReactNative.

  2. The createClass components are generated importing the create-react-class package, making it compatible with the current React release (15.5), and the next (16.0).

  3. Six, including -h --help.

  4. To be compatible with current and future versions of React, PropTypes uses the prop-types package.